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7jb7a0
|
why do other mammals all seem to love having their bellies rubbed, but for humans, tickling is bordering on unbearable?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7jb7a0/eli5_why_do_other_mammals_all_seem_to_love_having/
|
{
"a_id": [
"dr4y582"
],
"score": [
4
],
"text": [
"Do they like it though?\n\nDogs seem to enjoy it.. some cats will tolerate it.. but most other mammals don't like it. Horses are ticklish on their tummies and cows will kick you. These animals are eventually trained to tolerate human touch but don't really \"enjoy\" it.\n\nI said dogs seem to enjoy it. That's not the same as them actually loving it. They are showing their submissiveness to us. They like attention and they love being touched so, the combination makes it look like what they love is their tummy being touched but really what they love is our attention and the understanding that it is reaffirming a bond."
]
}
|
[] |
[] |
[
[]
] |
||
4982nh
|
how does your brains chemistry when listening and dancing to music compare to playing music on an instrument?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4982nh/eli5_how_does_your_brains_chemistry_when/
|
{
"a_id": [
"d0pq5ju"
],
"score": [
4
],
"text": [
"The most dramatic difference is that those two things are processed in totally different areas of the brain. \n\nListening to anything, including music, lights up the auditory cortex of the brain, located in the temporal lobe. Music that evokes an emotional response from you will also activate the limbic and cingulate regions of the brain, which are located deeper within the center. \n\nBut dancing and playing are physical activities, not passive sensations. These are things that come *out* of the brain, rather than go *into* it. Dancing is stimulated by the primary motor cortex, which is a band that runs across the top of the brain width-wise, and fires neurons down the spinal cord to the arms, legs, and trunk. If you're dancing randomly and spontaneously, that's about it, but if you're planning your dancing in your head (like if you have choreography), then you're also activating the premotor cortex, which is responsible for the planning of activities that haven't been stimulated by the motor cortex yet. The same is true for playing an instrument, but then the motor cortex is going to activate smaller, finer movements; fingering the strings of a guitar with proper rhythm, volume, and tuning is a much more precise activity than doing a two-step. If you're reading sheet music or playing a rehearsed piece, you're also activating the visual and premotor cortices again. If you're composing, you're activating even deeper parts of the brain, like the cingulate gyrus again.\n\nThe point is: it's all very complex, very synthesized, and *very* cool. Music in all its forms is very stimulating and healthy for the brain.\n\nIf you're interested in more in-depth analyses, Google has a great variety of literature published on precisely this topic, but I warn you that it's not exactly ELI5 material."
]
}
|
[] |
[] |
[
[]
] |
||
2nvc98
|
how is mobile internet ip traced?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2nvc98/eli5_how_is_mobile_internet_ip_traced/
|
{
"a_id": [
"cmh7kxh"
],
"score": [
3
],
"text": [
"Your mobile carrier maintains records of which IP address is assigned to your phone / mobile device at any given time. Your carrier will operate cell towers all around the city where you are located and since your phone / mobile device is connecting to those towers, it's possible for the carrier to triangulate your position (roughly) based on which towers your phone/device is in range of and communicating with. Some devices (particularly cell phones) also allow the mobile carrier to request GPS coordinates for the phone (e.g. for emergency locating purposes)."
]
}
|
[] |
[] |
[
[]
] |
||
2l711p
|
how do viruses or bacteria like the flu or strep survive 'out of season' when it seems like aren't not spreading?
|
Do they continue hopping between hosts to survive but just at an slower, unnoticeable level, or do they just become dormant until conditions are better?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2l711p/eli5_how_do_viruses_or_bacteria_like_the_flu_or/
|
{
"a_id": [
"cls1ttj",
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],
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2
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"text": [
"Flu season in the other hemisphere is the opposite of flu season in your hemisphere. So yes, it is hopping between host from one side of the planet to another, and then come back slightly modified. By the way, it is how flu vaccines can be predicted (and why they sometimes fail).\n\nStreptococcus are normally carried by many people without causing any infection. So, well, they are hopping too, and also are kind of dormant (in another person throat).",
"While flu season does occur during colder months in each hemisphere, acknowledging that as being how the virus or bacteria survives is a really bad answer. All diseases do not follow that pattern and it implies that the flu virus or the bacteria causing some other disease sort of moves about the earth with the seasons.\n\nThe first thing to note is that a virus or bacteria will have a natural reservoir. Some organisms can survive outside of a host and survive in the environment. Caulobacter which is actually nonpathogenic is a bacterium that was isolated from tap water. For many viruses and bacteria, there are different host organisms that the organism can colonize. Colonization of the reservoir organism will result in no disease or mild cases. Bats are often a reservoir.\n\nFurthermore, while the amount of cases increase, for the flu, there are still cases year round. \n\n\n\n"
]
}
|
[] |
[] |
[
[],
[]
] |
|
abh8hz
|
what are the factors that contribute to the price of gas in america?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/abh8hz/eli5_what_are_the_factors_that_contribute_to_the/
|
{
"a_id": [
"ed09byx"
],
"score": [
2
],
"text": [
"Local gas tax, distance from refineries, local competition (price war) and time of year (winter vs summer formula) are some reasons."
]
}
|
[] |
[] |
[
[]
] |
||
8jgcu6
|
how are genes responsible for specific things?
|
I often hear talk of being able to switch genes on or off for very specific traits, characteristics, or conditions (at least theoretically). My question is- is each gene responsible for 1 very specific thing (and if so how could that be), or is it more accurate to say that we may have identified a particular gene responsible for a particular thing, but don’t really know what else that gene influences? So, say we could “turn off” the gene for a certain form of color-blindness, might doing that have unintended consequences like increasing nipple hair? Also are genes binary on/off or something else?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8jgcu6/eli5_how_are_genes_responsible_for_specific_things/
|
{
"a_id": [
"dyzfs23",
"dyzlhpm",
"dz10uy7"
],
"score": [
3,
3,
2
],
"text": [
"i can give a simplistic example:\n\nthe proteins that make up human arms and hands are mostly the same proteins that make up fish fins (and bird wings, etc.)\n\nsome genes make the proteins, other genes turn the protein producing genes on and off.\n\na fish fin's proteins were turned off earlier than a human's arm so the fin is short, the arm is long.\n\nthere was an advantage to short fins for swimming for a fish and there's also an advantage to having long limbs for walking on land.\n\nan amphibian, like a frog, had the first option as a baby (tadpole) and then took advantage of the second option in adulthood. somewhere down the line the second option getting switched on became an advantage.",
"In short, it's complicated. Some genes we're pretty positive connect only to a specific trait. Other times multiple genes can be linked to similar traits that fill a similar spot (such as animal fur color) which can lead to interesting combinations depending on how they mix/express different combinations. Some traits might have multiple different effects (sickle cell anemia seems really bad, but it also happens to make you much more resistant to malaria as a related effect of the same trait). Or maybe you could end up with multiple combinations all leading to the same trait; if something goes wrong in a 12-step process then it doesn't matter on a trait-basis whether it was step 1 or 7, the end results will probably look fairly similar.\n\nLastly even inactive genes can have effects by turning on/off other parts of your genetic code farther down the line. So maybe changing this section here ends up activating a section down the line later even though it doesn't seem connected immediately (and it might do different things depending on what that newly activated section contains).\n\nSo you wouldn't necessarily be that bad off if you wanted to think that 1 gene = 1 trait, and that's the way that it often gets taught in earlier grades (since historically that's the way we thought it worked), but the truth is that if you look closer it is a lot more complex than that and we're only still discovering how some of these things actually work as technology finally lets us start looking at some of these effects.",
"\"So, say we could “turn off” the gene for a certain form of color-blindness, might doing that have unintended consequences like increasing nipple hair?\"\n\nYES! absolutely! thats why genetics is still such a growing field. they're still figuring quite a bit out, however, the basics are understood.\n\nthe analogy i've always heard is, genetics (or embryology) is less like building a house, and more like baking a cake. think of a blueprint. want a room here? it's 1:1 on the blueprint... will the room have a closet? here is the corresponding closet diagram in the blueprint. now think of a cake recipe. there isn't anywhere in the recipe that says \"assemble the cake to 4\" depth, fully cooked.\" there are not diagrams of triangular cake pieces in the recipe that you assemble into a round cake. you just add the ingredients correctly, in the correct amounts, bake it correctly, and get a cake that is (hopefully) what you intended! same with flavor, texture or density... now, if you're a skilled baker, you may know what adding 20% more butter might do. or using less salt. or preparing a wetter batter. however, it isn't 1:1, like a blueprint. and it may have consequences that make it inedible. geneticists the world over are trying to be better bakers right now. \n\nEDIT:\n\nhere is the article i was looking for. apparently, if you breed foxes into domestication, like dogs, they start getting floppy ears as well, just like you were talking about. changing one thing changes lots of unrelated things.\n\n_URL_0_"
]
}
|
[] |
[] |
[
[],
[],
[
"https://www.npr.org/2018/01/30/580806947/why-dogs-have-floppy-ears-an-animated-tale"
]
] |
|
4jr5yh
|
how were arch bridges made in pre-modern times?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4jr5yh/eli5_how_were_arch_bridges_made_in_premodern_times/
|
{
"a_id": [
"d38tad6"
],
"score": [
3
],
"text": [
"Build a frame work of wood. Stack stones until arch is complete. When you have the final stone in place and the arch can support itself, remove the wooden frame."
]
}
|
[] |
[] |
[
[]
] |
|
qcaq1
|
can someone explain why astronomers/scientists name some celestial bodies after gods?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/qcaq1/can_someone_explain_why_astronomersscientists/
|
{
"a_id": [
"c3wgh8z",
"c3wghie"
],
"score": [
7,
7
],
"text": [
"Most likely just tradition. Mercury Mars Jupiter Saturn and Venus are all visible fairly easily and have all been known for a very long time. When new planets were discovered, they kept the naming scheme.",
"A long time ago in places like Greece, Rome and even before that in really, really long ago places like Sumeria, and Egypt people made up stories about the stars/planets and the pictures they thought groups of stars made. These stories were usually about beings they considered to be gods or demigods (the word demigod here means \"half-god\" or \"almost-a-god\"). \n\nAt one time Rome was pretty much in charge of the known world for a really long time (around 1700 years). During that time they shared their stories about stars and planets being where the gods lived with everyone they were in charge of who didn't already have stories like that of their own. People got used to the idea, and it kind of stuck. \n\nSome scientists/astronomers today do it because really old texts and star charts have them recorded that way, and some because they think the old stories are cool or because after so many years it's kind of a tradition. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
bd0ik6
|
why is american candy packaging so much thicker than in other countries?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/bd0ik6/eli5_why_is_american_candy_packaging_so_much/
|
{
"a_id": [
"ekuy4ux"
],
"score": [
5
],
"text": [
"Americans have more money than people from most other countries so they’re fine paying the extra few cents for the packaging. And for developed countries, America has lax environmental regulation so you can use thicker material to make your product look better than others. \n\nFunny thing happened because of this, though with chips. The CIA once placed cell phones in potato chip bags (since the metal on the inside scrambles signals) to stop them being tracked. In Italy, though, investigators found evidence of covert ops since the bags in Italy are too thin to provide good enough shielding."
]
}
|
[] |
[] |
[
[]
] |
||
2kbdyi
|
what's the difference between compulsively lying, pathologically lying, and just plain lying?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2kbdyi/eli5_whats_the_difference_between_compulsively/
|
{
"a_id": [
"cljog5d"
],
"score": [
7
],
"text": [
"Compulsive: you can't really help it, even though you know you're lying.\n\nPathologic: you don't realize you're lying and you do it often.\n\nPlain old lying: you know it's wrong but you made the choice to lie."
]
}
|
[] |
[] |
[
[]
] |
||
2g33ba
|
why is the daily mail not generally seen as an unacceptable source for news, the same way that every other tabloid paper in the world is?
|
*EDIT: Sorry about the double negative! The title should say:*
**"Why is the Daily Mail generally seen as an acceptable source for news, unlike every other tabloid in the world?"**
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2g33ba/eli5_why_is_the_daily_mail_not_generally_seen_as/
|
{
"a_id": [
"ckf675x",
"ckf6e85",
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"ckf7262",
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],
"score": [
3,
7,
14,
2,
2,
2,
2
],
"text": [
"simply because many people don't know it is tabloid. it's not in sphere of interests of many people. \n\nprobably you don't know of top of your head tabloids in Germany, or Poland.",
"People post mail online links on reddit sometimes it pisses me off, as soon as I see the logo I leave the page; It is worse than a lot of tabloids (red tops) as it has so many people fooled into thinking they are reading the \"news\". I hate hate hate the daily mail",
"The Daily Mail is viewed by many in the UK who don't read it as a newspaper targetted at right-wing, older people who enjoy being angry. It is the UK newspaper equivalent of Fox News.\n\nThere was a joke many years ago that I am misquoting here but it was along the lines of:\n\nNormal newspaper: Gang of thugs attack defensless Polish man.\n\nDaily Mail: Illegal immigrant uses face to bruise the knuckles of group of helpless Brits.\n\n\nIt doesn't help that their former proprietor was a fan of facism.\n\nEdit - I've just realised that I misread your question as \"Why is the Daily Mail not seen as an acceptable....\"",
"_URL_0_\n\nThe daily mail are racist scum that supported the nazi's and run blatantly anti-semitic articles in the run up to WWII.\n\n_URL_1_hurrah-for-the-blackshirts/\n\n_URL_1_",
"I am American and I see it as a Tabloid, does the UK not?",
"It's a tabloid dressed up in a professional way.\n\nAs someone who spends alot of time following soccer transfers during windows, the mail are highly questionable when it comes to sources and normal write about gossip.\n\nAs mentioned, they target a niche market- older, right leaning citizens who want mixture of world affairs /uk issues and tabloid gossip dressed up in a formal way. The difference between the mail and the sun for example is that there'll be more focus on political issues and the celebrity gossip will generally only be the more outstanding stuff e.g celebrity facing domestic charges over celebrity caught binging in a night Club( although occasionally it does get reported but only on more prominent British orientated /recognisable to the British people -like Jamie Oliver or Gazzer as opposed to Jay-z or Jimmy fallon, because less British people who fit the mails target audience are aware of these people.)",
"You have a double negative in your question which is confusing people. "
]
}
|
[] |
[] |
[
[],
[],
[],
[
"http://www.youtube.com/watch?v=5eBT6OSr1TI",
"http://tompride.wordpress.com/2014/02/27/its-time-the-daily-mail-apologised-for-supporting-hitler-and-its-anti-semitic-past/",
"http://tompride.wordpress.com/2014/02/27/its-time-the-daily-mail-apologised-for-supporting-hitler-and-its-anti-semitic-past/hurrah-for-the-blackshirts/"
],
[],
[],
[]
] |
|
armpt8
|
how do we get weather data and how come it's so unreliable sometimes?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/armpt8/eli5_how_do_we_get_weather_data_and_how_come_its/
|
{
"a_id": [
"ego7iak",
"ego7ocg"
],
"score": [
2,
3
],
"text": [
"There are massive networks of distributed weather equipment that sends data from all over to be aggregated into a weather model. Because it's just a model, it's not 100% accurate. They also take the differences between predicted and real weather and incorporate it into the model for better prediction accuracy.",
"It’s a very very complicated system. \n\nThere is a network of weather reporting systems. Meteorologists take the information reported from those systems and plug those into simulations. \n\nUnfortunately weather is extremely sensitive to tiny differences in measurements. Imaging a simulation running on the real data and a simulation with a hundredth of a degree difference in temperature from one weather station: their predictions would look very different after a while, even though they were almost entirely the same at the beginning. \n\nSince no weather reporting system can be precise to the point that we would be able to perfectly report the weather, it still varies quite a lot from our forecasts. A whole lot of unpredictable things that the reporting systems can’t catch end up being very influential. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
5xj1ma
|
where does the phrase "indian giver" come from?
|
It seems to me the white man did most of the "takesy-backsies" in American history.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5xj1ma/eli5_where_does_the_phrase_indian_giver_come_from/
|
{
"a_id": [
"deig34x"
],
"score": [
4
],
"text": [
"The phrase dates back to the early Colonial period in present-day New England. The tribes in the area had customs involving gift exchanges, of which the Anglo colonists knew nothing. So, at a gathering an Indian might hand an Anglo a gift _expecting one in return_. When none was proffered the Indian would quite rightly say \"that's not how this works, gimme that back.\" Normal human interaction that wouldn't be out of place at a modern Christmas party. \n \nAn aspect to history that I think has been lost is that at the time the Indians were the wealthy, successful, sophisticated people and the Anglos were the grubby poverty-stricken immigrants. \n\nYou really should learn more about history before judging an entire race."
]
}
|
[] |
[] |
[
[]
] |
|
3ezgka
|
how do hunters do more for the conservation of species than anti-hunters?
|
I've heard this argument many times before, and again today in relation to Cecil the Lion, but I still don't understand it.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3ezgka/eli5_how_do_hunters_do_more_for_the_conservation/
|
{
"a_id": [
"ctjusc2",
"ctjutvj",
"ctjuwaq"
],
"score": [
3,
2,
5
],
"text": [
"Hunters usually have the most to gain from conservation. If species go extinct, that's one less thing they can hunt.\n\nWhether that actually translates to hunters actually going out and fighting the destruction of species, I couldn't tell you.",
"Hunters buy hunting licenses which are used to pay for programs to ensure that those species do well. The hunters themselves can also be important to prevent overpopulation by declaring it hunting season when there's too many animals.",
"They help to control populations of animals. Take deer, for example, they reproduce rapidly, and in turn get killed and injured for stupid reasons.\n\nThe money spent on expensive hunts and tags go towards conservation and protection of wildlife. The DNR in Michigan is incredibly dedicated to the protection of animals, and they couldn't do it without hunters.\n\nBy having established hunting laws and regulations, you encourage people to not hunt illegally, and encourage people to take only the legal limit of animals. People are going to hunt no matter what, so rather then them going into an area and extinguishing an entire herd of deer illegally, have him/her pay a couple dollars to take a few legally.\n\nBy controlling non-predatory populations, you help to control, and therefore protect predatory populations. Wolfs for example, eat deer, and if you control a deer population, you prevent the wolf packs from growing too rapidly, and begin to kill livestock. When livestock is killed, farmers will slaughter entire wolf packs to protect their livestock, but keeping numbers in check, you prevent predatory extinction.\n\nAll of this is proven to work, and has been working for some time, and they wouldn't be doing this if it didn't make sense. There are a lot of good people who love animals, and hunters are included in that group.\n\n"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
3zfzw7
|
when a news headline says a country is selling weapons to another country who's actually selling it?
|
I'm watching a documentary about arms dealing really curious on who in the government sells weapons or is companies like Barrett selling directly to different groups and countries?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3zfzw7/eli5_when_a_news_headline_says_a_country_is/
|
{
"a_id": [
"cylrz1w"
],
"score": [
3
],
"text": [
"There are two ways a country sells a weapon to another country. \n\n* Country buys from weapon company and then sells it to other country; being a middleman. This either from their surplus or a result of a defense contract. \n* Country allows weapon company in their country to sell weapons to the other country. Lots of weapon company have some form of contract restricting their business to the host country. "
]
}
|
[] |
[] |
[
[]
] |
|
7mrx7o
|
how does the camouflage skin of octopi, squid, and cuddlefish match their surrounding color and texture so accurately?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7mrx7o/eli5_how_does_the_camouflage_skin_of_octopi_squid/
|
{
"a_id": [
"drwjudz"
],
"score": [
3
],
"text": [
"They have highly specialized cells that get a signal from the brain when it detects a certain surrounding colour and then expand or contract in order to change the pigment in the cells. You can notice that they’re never fully campouphlaged but only partly and being under water helps them become ‘invisible’. \n\nDue to lack of time I’ll post a link here:\n_URL_0_"
]
}
|
[] |
[] |
[
[
"https://www.google.nl/amp/ocean.si.edu/ocean-news/how-octopuses-and-squids-change-color%3famp"
]
] |
||
60w1d6
|
why is it important to wear a hat and scarf to keep warm?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/60w1d6/eli5_why_is_it_important_to_wear_a_hat_and_scarf/
|
{
"a_id": [
"df9pkq6",
"df9prsi"
],
"score": [
3,
2
],
"text": [
"Covering your body parts in cloth is necessary to keep them warm in cold weather, whether it's your head or your legs or your butt. It's a myth that we lose 75% of our body heat through our heads -- but it is true that your head would be cold without a hat. Just as your legs would be cold without pants. The colder it is, the more pieces we need to wear to stay warm.",
"Your question is most likely related to the theory that we lose most of our heat through our heads.\nThat is actually a myth, we lose heat evenly throughout our body. Hats and scarfs cover the parts of our body that are otherwise left uncovered in normal temperatures.\n"
]
}
|
[] |
[] |
[
[],
[]
] |
||
2sfs67
|
why does setting a magnet next to a tv mess up the colors?
|
The other day I accidentally set an amp too close to my tv and the magnets distorted the colors. I moved the amp and later turned the tv on and the colors were just fine. Can anyone explain this? Also sorry if this was already asked, I searched and didn't find anything.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2sfs67/eli5_why_does_setting_a_magnet_next_to_a_tv_mess/
|
{
"a_id": [
"cnp1ddx",
"cnp1h5h"
],
"score": [
6,
4
],
"text": [
"because the picture is formed by a beam of electrons. electrons are charged particles and can be attracted or repulsed by a magnet (in fact, that is how the TV \"steers\" the beam to begin with. with electromagnets)\n\nthis only works with old style CRT tubes, btw. ",
"I assume you have a CRT (the old school glass-front tv)? \n\nWorking under that assumption the TV has an electron tube in it. That's exactly what it sounds like. It's tube that makes electrons. The electrons, released in the tube, shoot through a varying magnet field that aligns them to the right spot on the TV screen (it basically aims all the electrons being shot out of the tube). The electrons collide with the glass on the front of the TV that's loaded with special minerals that ,when hit by electrons, emit light. That's how your TV makes a picture.\n\nElectrons are pretty neat in that they can get influenced by magnetic fields. When you put a magnet next to the screen the field pulls the electrons toward the magnet and distorts the picture. \n\nThe magnetic field can also magnetize the screen a little, and a little is all it takes. If the screen gets magnetized you'll see a the same effect as you did when the magnet was near the TV even though you removed the magnet. You can do something called Degaussing which will remove the mag. field from the tv screen and return the screen to normal.\n\nHere's a cool video I watched today that shows a really big magnet next to a tv screen (among other stuff): [Monster Magnet Meets Stuff](_URL_0_)"
]
}
|
[] |
[] |
[
[],
[
"https://www.youtube.com/watch?v=_yEu2R1gYSs"
]
] |
|
3tfalw
|
how do authenticators work?
|
How is that one second later when the a code changes is no longer valid so quickly?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3tfalw/eli5_how_do_authenticators_work/
|
{
"a_id": [
"cx5mmp0"
],
"score": [
13
],
"text": [
"To create an authenticator, you need three basic things:\n\n* A clock\n* A formula\n* A seed number that's unique to your authenticator\n\nLet's look at the formula first - we'll keep it simple, we'll say that our formula is:\n\n number displayed = (minutes since 00:00 GMT on Nov 19th 2015) * (seed number) \n\nIt's now 12:25 GMT (ish), so that's 745 minutes since 00:00. If your seed number is 3, then your authenticator will display the number 2235.\n\nIf your authenticator can do that sum, so can the server you're trying to connect to. They know your authenticator's seed number, and if the clock on your authenticator and on the server match, then the server can know what number it's expecting from your authenticator at that moment.\n\nOK, my example is over-simplified by quite a lot - the seed number and formula in a real authenticator will be far more complicated than that - but that's the general gist of it."
]
}
|
[] |
[] |
[
[]
] |
|
2hsj26
|
why must we have commentators during live televised sporting events (usa, probably others?)
|
Actually attending a sporting event spares you from talking heads filling the otherwise pleasant silence with random facts, musings, BS. In 2014 why don't I get the option to mute only them during a game?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2hsj26/eli5_why_must_we_have_commentators_during_live/
|
{
"a_id": [
"ckvldq6",
"ckvmo9f"
],
"score": [
3,
3
],
"text": [
"For less knowledgable people to keep up with what's going on. ",
"Using football as an example.\n\nThere's 22 people on the field + refs at any given time.\n\nAll of them are relevant to the play. How many times have they pointed out something to you that you otherwise would have missed? Missed penalties, interesting statistics?\n\nThis is less useful in a lot of other sports, though. Baseball notably needs exactly zero commentary. Nothing is happening outside of the pitcher/batter/the guy specifically involved at that moment.\n\n"
]
}
|
[] |
[] |
[
[],
[]
] |
|
3itbyj
|
why windows 10 allows so much bloatware and malware to be downloaded with the os
|
Sorry for grammar, I'm on mobile.
Why would developers allow so much bloatware and malware to be installed when all it does is cause people a lot of problems and wastes their time.
Edit: Thanks for all the advice, everybody. Im off to bed. Will try to fix it tomorrow
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3itbyj/eli5_why_windows_10_allows_so_much_bloatware_and/
|
{
"a_id": [
"cujgm5t",
"cujgntr"
],
"score": [
3,
3
],
"text": [
"What bloatware are you referring to? I've installed a fresh copy of windows 10 and have seen none of this.",
"There is no malware. \"Malware\" is a catch-all term for \"bad\" software (the \"mal\" prefix comes from the Latin for \"evil\"). It covers viruses, trojan horses, browser hijackers, etc.\n\nAs far as bloatware, there's some software made by Microsoft that they're trying to increase the user base for, but very little of it."
]
}
|
[] |
[] |
[
[],
[]
] |
|
d752rv
|
whats the purpose of a birth certificate? and does it really represent a corporation?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/d752rv/eli5_whats_the_purpose_of_a_birth_certificate_and/
|
{
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"f0xjcfd",
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"score": [
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2,
3,
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],
"text": [
"It's a certificate saying when and where you were born. Who your parents are. When you were born. It's a government document that can be used as a piece to prove your identity.\n\nNo. Birth certificates don't represent a corporation?",
"Where did you hear that a birth certificate represents a corporation?",
"While humans have been recording birth in various ways for thousands of years (including written church records, oral histories, etc), we didn't have an official birth certificate, as we recognize them today, until 1902, when the U.S. Congress created the Bureau of Census to develop birth registration areas and a standardized birth registration system. It took several decades of revisions for the birth certificate forms to become what we know today, though. \n\n\nOne of the main reasons for inventing official, standardized birth and death records was for tax purposes, property ownership, and public health. When the U.S. started seeing massive number of immigrants coming in, people who often ended up stuck in dark, dirty, cramped tenements where diseases are easily spread, folks started realizing it would be smart to keep records of all the people so that they could track who was dying where, and from what, as well as tracking things like infant mortality, and the effects of attempts to prevent, treat, and cure disease outbreaks. \n\n\nThe Bureau of the Census retained the authority for producing national vital statistics until 1946, when the function was transferred to the US Public Health Service as the National Office of Vital Statistics. It was then reorganized in 1963 as the Division of Vital Statistics of the National Center for Health Statistics (NCHS). From 1915 to 1933, national birth registration areas in the US progressed from 10 states and the District of Columbia to all the states except for Alaska and Hawaii, which started reporting births upon becoming states in 1959. \n\n\nThese days vital statistics for the US are collected and published through a decentralized, cooperative system, not solely from a central federal entity, leading to differences in the kinds of data and how they are collected in different states. The responsibility for registration of births is vested in the individual States and certain independent geographic city registration areas. The federal government then utilizes the data not only to understand health issues and publish national statistics, but also to evaluate health and welfare programs. And of course we now use birth certificates as proof of citizenship when we need to register to vote, get passports or new driver's licenses, etc. \n\n\nUnfortunately, many Americans have been effectively shut out of the system as more and more things have required a birth certificate. One estimate I saw says that roughly 3 million American citizens, typically older people, have never had a birth certificate, usually because they were born at home and the parents either didn't think it was the government's business, or lived in a rural area with no hospital or governmental office anywhere near them, or never had any reason to believe that such a document would ever be necessary, which is a reasonable assumption considering how relatively new official birth certificates are. \n\n\nEven worse, many of these people DO have documents such as Baptismal certificates, but as more and more states are requiring very specific types of ID to vote, types of ID that you can't even get unless you have a birth certificate, many of our older folks (and some younger people, it depends) are being denied a whole host of rights and services.",
"Here's an attempt at explaining the Sovereign Citizen conspiracy theory. Keep in mind, this is all nonsense and believing it could convince you that you are allowed to do things that will land you in jail. That said, he we go.\n\nStarting with stuff that is actually true, you may or may not know that companies can do things like opening bank accounts, enter contracts, file lawsuits, take out loans, pay taxes etc in the name of the company. (It wasn't always this way. Once, if you wanted to sue a company you couldn't, instead you had to sue the people who owned the company).\n\nThe actual reason that companies can act in their own name is because the government decided many years ago that being a \"person\" wasn't limited to just flesh and blood humans. Lots of things could be people, including flesh and blood humans and also companies.\n\nSovreign Citizen believers say that this is nonsense. They say that governments can't just decide to make random things into people. It must be a lie and the truth must be that companies can do the things I listed before because that's just something that companies can do.\n\nThis creates a logical problem though. If only a company can open a bank account, or enter a contract or pay tax or go to court, how come average people on the street seem to be able to do these things too? The answer, according to sovereign citizens is that some secret shadowy force has secretly created a company in the name of every person on earth. So whenever you go to court or open a bank account or whatever, it's actually the company created in your name that is doing these things on your behalf.\n\nNow, having dreamed up the existence of these secret companies, sovereign citizens find reasons to believe that laws they don't like actually apply to the secret company not to the flesh and blood individual. Or they find ways to believe that debts they don't feel like paying are actually owed by the secret company and not by the individual.\n\nFor example, don't like being told you can't be a violent racist? Well, lucky for you, the constitution and all the equal protection amendments are supposedly a contract (actually they aren't, but let's play pretend) and since contracts are entered into by your company not you, you in the flesh are free to be the fullest nastiest racist you like. Hooray! /s\n\nThat's really what motivates it all. People looking for a way to justify being horrible law breaking, social norm violating buttheads. And for this reason, you'd do well to steer clear. They inevitably alienate all their friends and too often wind up committing crimes, hurting people or going to jail."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
1vz53b
|
why can so many companies produce windows-based computers, but only apple can produce macs?
|
You always see so many different styles of windows-based computers because tons of companies make them. But you only ever see Apple with their Macs. I'm guessing it's a copyright or something.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1vz53b/why_can_so_many_companies_produce_windowsbased/
|
{
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],
"score": [
2,
2,
8,
2
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"text": [
"Pretty much copyright, yeah. Microsoft makes Windows and lets anyone install it on any computer as long as you pay them enough money. Apple makes both hardware and Mac OS and says that Mac OS may only be installed on Mac hardware. It allows them a lot of control over the product and ultimately causes it to perform somewhat better in theory.",
"Microsoft doesn't make their own computers (at least, they didn't for decades), instead it sells licenses of Windows to computer manufacturers so that they can produce computers with Windows on them. Apple doesn't sell licenses, they just make their own computers.",
"When IBM first built the PC back in the early 80s, it chose to use off the shelf components (instead of custom) to meet the tight project deadline. There was one custom chip, the BIOS. Compaq was able to reverse-engineer the BIOS chip and create their own compatible chip, which allowed them to make a computer that was completely compatible with the PC. The floodgates opened, and now anyone can easily build a PC compatible machine. This is aided by the fact that the OS for the PC, DOS (and later Windows, Linux, etc) was produced by a separate company and was available for purchase separately from the PC.\n\nApple, on the other hand, controlled both the hardware and software for their machines. They briefly allowed 3rd party machines to be sold, but that was shutdown when Steve Jobs returned to the company. It is technically possible to build a Apple compatible machine, usually called a Hackintosh, but it is a violation of the OS X license to run the software on a machine not built by Apple.",
"Apple only allows their software to be installed on their computers, legally. You can create a \"hackintosh\" illegally. Macs sell for a lot more, because that's the only computer that legally can have Mac OSx. Windows allows their software to be installed to any computer, as long as it is paid for. This creates a large variety of PCs and competitive prices among companies. "
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
2so4qt
|
why are scientists trying to clone a wooly mammoth using ancient dna when they could be cloning endangered animal species, such as the white rhino, whose dna we can still collect?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2so4qt/eli5_why_are_scientists_trying_to_clone_a_wooly/
|
{
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"cnrb721",
"cnrc42z",
"cnrhbid",
"cnri9ja",
"cnrkyh0",
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"cnrolud",
"cnrovzi",
"cnrpkc3"
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"score": [
14,
12,
144,
105,
8,
3,
3,
2,
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"text": [
"[What makes you think they aren't collecting the DNA of endangered species already?](_URL_0_). ",
"Why not do both? And really, we already collect DNA of endangered animals. Cloning a mammoth is more trying to push the limits of what is possible. And it's by pushing the limits we find out new things.",
"As has already been said, there are research efforts focused on both. However, tackling the technical challenges of piecing together a genome that hasn't existed for thousands of years would benefit the scientific community more than trying to keep a species alive that nature can no longer support. Sequencing the mammoth genome would represent a major achievement in our ability to study the genetic content of extinct species and could ultimately lead to greater insight into the origins of cellular life. This is the reason it gets more funding and media attention.",
"Most animals that are facing extinction is due to habitat loss. Unless you also solve the issue of preventing future habitat loss there isn't a point to cloning them even if you had enough distinct individuals to clone.",
"Cloning, especially in such a small population could have horrible effects on the species gene pool. Breeding programs for endangered species focus heavily on maintaining genetic diversity, because it ensures the survival of the species in future generations. There could also be problems with clones having weird genetic mutations and getting that into the population.",
"Funding. Pull off cloning a Wholly Mammoth, and that lab can write its own ticket. Next up? anything you want, mr billionaire...",
"These things are not either/or, both are being worked on.",
"which is cooler and attracts more public attention, thus grant money and funding. Sadly, that's the true ELI5 answer\n",
"Raising a mammoth from the dead is super interesting and an unprecedented scientific leap. You can get a baby rhino with a bottle of cialis, peach schnapps, and a copy of ace ventura 2 ",
"Because you don't get anywhere near as much media attention trying to clone animals that are still around. I wouldn't even have clicked on this post if it didn't mention cloning an animal that's been extinct for a very long time."
]
}
|
[] |
[] |
[
[
"http://abcnews.go.com/Technology/story?id=98919"
],
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
||
5qx2uf
|
the purpose/goal of the 90 day muslim ban
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5qx2uf/eli5_the_purposegoal_of_the_90_day_muslim_ban/
|
{
"a_id": [
"dd2qowl"
],
"score": [
2
],
"text": [
"**It's not a Muslim ban....**\n\n\nIt's a ban on immigration from certain countries that have a history of supporting terrorist acts. It's to give us time to review our vetting process in regards to these countries, so we can better protect our own country."
]
}
|
[] |
[] |
[
[]
] |
||
27uhnx
|
why don't places that serve alcohol post the prices for it on the menu?
|
Why do I have to ask, why isn't it just made easy with prices posted?
And that's like 90% of places!
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/27uhnx/elif_why_dont_places_that_serve_alcohol_post_the/
|
{
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6,
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"text": [
"Because you're more likely to make stupid decisions that way.",
"Because more people would not be inclined to order the drink if they knew how expenisve it would be before ordering it.",
"I must go to the wrong restaurants. Most list the price of beverages on back page.\nI would assume its so you buy $14 cocktails",
"Are these upscale places? Most of the places I go to have prices listed, even fancy places. I've noticed that the fancier the place, they use single digits, e.g. Glass of wine - 8, no dollar sign no decimal point. And places like TGIFridays always have promotions, especially on beer and wine, so they don't place prices on some of the beer menus because they want you to bring it up so the server can mention the specials. 2 for 1 Coronas, etc. That's the only thing I can think of, I worked at the ground round for 4 years when I was younger and they were always pushing drink specials. ",
"Blind ordering is a mistake you make only once.. \n\n\"Oh, I see my pint of Shiner was $8.50. Fantastic.\"\n\n",
"I know in a couple of places I worked in, they had to keep reprinting menus due to changes in taxes, changing prices from the liquor distributors,etc. After the fourth or fifth time of completely reprinting the menus in a handful of months, they just stopped including the price.\n\nFor the most part though, probably like everyone else said, so that customers order expensive items they may not have otherwise.",
"Every business is required by law to post the price for every product and service in the EU. Where do you live?",
"Can't think of a single place I've ever had a drink in that didn't have the prices up. But then that's a requirement of British and EU law. ",
"All I can think is if they use different brands of alcohol it can cost more (well vs top shelf) so the price might vary? "
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
|
ycr6q
|
the julian assange controversy, from the beginning.
|
So for some reason, at the start of the controversy, I missed one day of the news and have been lost as to exactly what is going on with Assange, how wikileaks functions and how it's illegal.
Please explain the Assange controversy, from the top, like I'm five.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/ycr6q/the_julian_assange_controversy_from_the_beginning/
|
{
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"c5uf19d"
],
"score": [
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],
"text": [
"He started Wikileaks in 2006 and leaked information about political and religious groups for a bit. Many didn't seem to worry too much as the information leaked concerned corrupt leaders in Somalia or issues with the Church of Scientology. But once he started targeting the US, powerful people started to care. He released little leaks like the handbook for those working at Gitmo and Palin's emails. In 2010 with the help of Private Bradley Manning of the US Army, Wikileaks started to release a boatload of classified files (next month Manning will be tried for aiding the enemy, an offense that could result in execution). Some files showed the US military acting in a way which was embarrassing to the US government. Wikileaks has also released private conversations between US gov officials and foreign diplomats. Julian Assange has been hopping around the globe to avoid some very serious and heavy charges the US wants to place on him, such as treason or terrorism which could get him executed. \n\nOne country where he was chillaxin' was Sweden where two charges of rape have been brought up against him. It is for these rape charges the Brits want to arrest and ship him off to Sweden to stand trail. Assange claims these charges are false and Sweden only wants to send him to the US where multiple charges will be brought against him. He has pissed off a lot of people, and not just in the US. He walks a fine line and Wikileaks is inches away from being considered a terrorist organization. \n\nIt is for this reason I am confident the NSA will find and review this little slice of internet conversation only to store it indefinitely. So lets just take a moment to say hello to a third party reading this post and wish them a good day."
]
}
|
[] |
[] |
[
[]
] |
|
1qtixj
|
why lifting someone against its will seems way heavier than someone of the same weight who passively let you do it?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1qtixj/eli5why_lifting_someone_against_its_will_seems/
|
{
"a_id": [
"cdgbcs0",
"cdgbey9"
],
"score": [
2,
3
],
"text": [
"As a woman I will do anything I can to avoid seeming heavier when a guy picks me up. \n\nNote to self - do not struggle!",
"If it's against their will generally it's because they're struggling, so it's harder to do a smooth lift. Even if not struggling they may 'hunker down' bending their knees and dropping their centre of gravity lower, making it harder for someone to lift them, especially people taller than them.\n\nHowever I would say lifting someone as dead weight is even harder. Trying to carry someone who is unconscious is extremely difficult. Limbs flopping everywhere, head and upper torso just lolling about, God it's a nightmare! \n\nFYI: I am NOT a murderer/rapist. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
3c7ftu
|
why did single-payer healthcare fail in vermont?
|
If it wasn't successful in Vermont, how can it be successful on a national scale?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3c7ftu/eli5why_did_singlepayer_healthcare_fail_in_vermont/
|
{
"a_id": [
"cst1fok"
],
"score": [
4
],
"text": [
"It wasn't successful because when people saw how much it was going to cost, they balked.\n\nWe have a really expensive healthcare system. Our system was not designed to minimize costs, it was designed to make sick people well regardless of the cost.\n\nWhen Vermonters saw what they'd have to pay to provide universal single-payer healthcare, a majority decided they'd rather not pay that much of their income."
]
}
|
[] |
[] |
[
[]
] |
|
2qa5s6
|
why does my new tv make everything look like an 80s sitcom?
|
I can't even explain the phenomenon, exactly, but everything looks like Alf looked. Like... the... film. Or. something.
EDIT: I BELIEVE THE MYSTERY HAS BEEN SOLVED. Thanks to /u/Luktrocity, I have found out about a thing called the Soap Opera Effect. Thanks, dude!
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2qa5s6/eli5_why_does_my_new_tv_make_everything_look_like/
|
{
"a_id": [
"cn488hz",
"cn4blbw"
],
"score": [
4,
3
],
"text": [
"What kind of tv do you have? Just off the top of my head do you have auto motion plus turned on? ",
"It's called frame interpolation. Your TV calculates subpictures when frame interpolation is activated. That means between frame 1 and frame 2 your TV generates the frame 1.5 using complex algorithms. So if you are watching film in 30 fps your TV will make it look like 60 fps. Soap Operas also use(d) to be recoded in 60 fps, thats how you get the impression of a sitcom-like picture. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
4jsthr
|
why do some programs require certain files to be on the same hard drive that my operating system is on, and others don't?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4jsthr/eli5why_do_some_programs_require_certain_files_to/
|
{
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5,
5,
3,
2
],
"text": [
"In a modern OS, I can't think of any reason that a user program would require certain files to be on any particular drive. The only thing even close that I can think of is the Linux soft links have to be on a single filesystem.\n\nIt's more likely that the programmers were lazy and hard coded the path or did everything naively with relative paths. That would make the program have a hard time going across filesystems especially in Windows where you're guaranteed to have a C: drive but other drives are unpredictable.\n\nTLDR; Probably lazy programmers.",
"Hardcoded paths to files are quicker/easier to program.\n\nSome files are shared libraries intended to be shared with other programs, and tend to be placed on the OS drive.",
"This day and age, it boils down to lazy programmers. IE the program Ninite, they publicaly said they won't allow you to select installation paths because they didn't want to, not because they couldn't.",
"It's been mentioned, but it comes down to how the program was written.\n\nPrograms 'should' be looking for a path variable (or Registry key) to tell it where its files are. These are meant to be easily changed and are updated when you change certain configurations in Windows - I'm not 100% on Unix/Linux.\n\nYou can see some of these variables by opening a command window and typing 'set'. The Registry is a bit different.\n\nIf a program is written to look at C:\\Settings\\, it will always look there, regardless of whether or not it exists on that drive, and will fail if it isn't there.",
"Because they're written that way, and no other reason. (maybe other reasons, but that's more like explain like I'm an intern trying to debug a program)\n\nAs long as a program is able to find the resources that it is looking for, either by itself or via the OS (drivers, etc), it can create the working set of memory that it needs to function, and it will also have the references to read and write permanent data.\n\nIt's the common case that you don't need need to look elsewhere on the system, and it's \"easier\" to not have to write scalaeble code in the first place. It's very easy to say \"get the files from the folder this program is running in\", and much more difficult to set paths to search them out on unknown systems, with unknown permissions.\n\nNewer programs and paradigms tend to be more adaptive, but amateur programmers that haven't run into the issue don't program against it, and programs being made in a time crunch may not worry about things like that over making it work.\n\nA really simple example is that on C:\\ and D:\\ drives, you reference the drives by those notations, so if I'm on D:\\ and I want to navigate to \"the root of the drive\" I end up at D:\\, but I don't know that there even is a C:\\ drive without either brute forcing it, or querying the operating system for drive info. \n\nELY5: If you are dropped off inside a new super market, where clothes are, and you want candy, where do you go? \n\nIf it's one big building, you can just walk around and find the sign that says \"candy\" and you're good. \n\nBut if it's halloween and they moved all the candy to a different building because SO MUCH CANDY, you wont be able to find it because you don't know where to find it. Even if you know it's not in the building, you don't know where else it could be. Is it at McDonald's, your friend's house?\n\nHowever, if you've been *programmed* to ask someone for help, you should be able to find the candy.\n\nNot all kid_wants_candy.exe are programmed to ask for help."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
||
2qouyi
|
why is it that snot will dissapear in a nostrel and then come back a second later?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2qouyi/eli5_why_is_it_that_snot_will_dissapear_in_a/
|
{
"a_id": [
"cn855y1"
],
"score": [
6
],
"text": [
"The ones disappeared disappeared, the ones that comes back are actually a fresh batch of soldiers."
]
}
|
[] |
[] |
[
[]
] |
||
6b01uk
|
why is it not illegal to advertise things such as "hexagonal alkaline anti-oxidant water" and other products clearly targeted to gullible people?
|
[This] (_URL_0_) is type of thing is what I am referring to.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6b01uk/eli5_why_is_it_not_illegal_to_advertise_things/
|
{
"a_id": [
"dhip82k"
],
"score": [
8
],
"text": [
"If you don't make false claims about the product's health effects, you may not be doing anything illegal. \n\nIf you do make false claims, you are breaking the law, and regulators will in fact shut you down -- and may make you pay huge fines too. It takes time."
]
}
|
[] |
[
"https://ecosway.uservoice.com/knowledgebase/articles/90241-what-is-the-hexagon-alkaline-water-filtration-syst"
] |
[
[]
] |
|
2gwfxm
|
why is the nfl being criticized for not suspending physically abusive players? shouldn't said abusers people be in jail or prison?
|
I assume that if they are in jail or prison, that they would not be able to play football for their team, suspended or no.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2gwfxm/eli5_why_is_the_nfl_being_criticized_for_not/
|
{
"a_id": [
"ckn5t4m",
"ckn94vj",
"cknezzh"
],
"score": [
12,
4,
3
],
"text": [
"It is just for the image of it.\n\nThe NFL feels that if their players get a bad repuation then sponsors will leave. The NFL, like most businesses, are in it for the money. If people feel the league is filled with abusive thugs they may not watch the game and advertisors may not buy ads.\n\nDomestic abuse has always been a problem but until Ray Rice no one really cared enough to make a stink about it.",
"The most recent round of abusive players are still awaiting court dates which could take months to happen. Domestic abuse crimes, while terrible, generally don't call for remand unless someone died. So until they receive a guilty verdict, they won't go to jail and, depending on the sentencing, might only get probation/fines. And remember, our justice system is SUPPOSED to be innocent until proven guilty. None of us know the true facts of the cases. Just because they're accused doesn't mean they actually did it.\n\nAs for why the nfl is taking heat, like most others have said before me, athletes are role models and advertisers bring in money. You don't want abusive role models or for you advertisers to pull their contracts if they think you're setting a bad example for their brand.",
"Allow me to interject as a police officer:\n\nJust because someone commits an assault, doesn't mean that they will spend even a moment in jail. If given an unsecured bond or a written promise to appear (most likely in simple misdemeanors like assault or marijuana possession) then they walk straight from the magistrates office to their cars and leave. These rich athlete types also have lawyers that God himself fears. \n\nThe people who spend time in jail are the ones who the magistrate (or the charging officer) believes are assholes or will skip out on court in my experience. This is the legal precedent of discretionary law enforcement. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
9ramgr
|
what happens to the body’s chemistry during an autonomous sensory meridian response?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9ramgr/eli5_what_happens_to_the_bodys_chemistry_during/
|
{
"a_id": [
"e8fjspc",
"e8fv4h3",
"e8g03b7"
],
"score": [
3,
2,
2
],
"text": [
"We don't know. We're still not even sure whether or not ASMR is a real thing. Clearly, people are experiencing something, but the phenomenon may be caused by any number of effects, a combination thereof, etc.\n\nThere's some evidence of altered brain activity during ASMR but nothing particularly conclusive yet, and nothing that I could find on chemistry specifically.",
" & nbsp;\n\n/u/FiveDozenWhales basically hit the nail on the head. If you want a short, 2-sentence answer, check out their comment. If you want to stare at something long enough that you become worried a coworker will call you out on reading a Reddit post at work, you're in the right place.\n\n & nbsp;\n\nThe issue is that ASMR is not even well-defined yet (scientifically). A quick peak at the scientific literature shows that it only started getting attention via publications around 2012. That said, here's some info from my research into it (note below info represents several experimental studies and several review papers; nothing set in stone):\n\n & nbsp;\n\n1. Folks' affect mood (how they felt; subjective, out of 100 with \"100\" being the best they've ever felt) improved greatest during interaction with the ASMR media (~35-60 before ASMR, ~70-80 during). Participants also reported still feeling some degree of mood boost after disengaging with ASMR media (~45-65 @3+ hours)\n\n1. \"Tingles\" were reduced after some survey participants began taking psycho-active medication (anti-depressants, sleep aids).\n\n2. Researchers seem to believe the effect on mood stems from A) watching the media with the intention to relax/care for yourself in someway and B) simulating intimacy. The 2nd point is strongly reflected in the high % of survey participants citing whispers or \"close attention\" as triggers. Also because of that latter point, male-created ASMR tends to be more difficult/less popular as the male voice is known to incite more feelings of fear or discomfort versus the female voice (on average; known psychological phenomenon). \n\n3. Survey results indicated more severe depression reduced the magnitude of \"tingles\" BUT participants with more severe depression experienced a greater improvement in mood after interacting with ASMR media compared to \"regular\" participants. \n\n4. The sensations reported by AMSR consumers bears more than a passing similarity to the state of \"flow\" described by Csíkszentmihályi (you can look this up on your own; there's A LOT of publicly available material on this topic)\n\n5. The one paper I found looking at specific physiological/neural data (the default mode network, DMN, a region of the brain which is involved in thinking about self, others, and the past/future) used fMRI scans to look for difference between resting ASMR and resting non-ASMR brains. They found the DMN was overall less connected in the 11 ASMR brains compared to the 11 controls, but was more connected in the cortex specifically. Actual activity in these regions wasn't different. Because the differences observed are linked with reduced attention control, the authors suggest ASMR might be a result of an inability to suppress emotional-sensory responses that is normally inhibited in the general population. They made careful claims that the statistically different results they saw does not necessarily translate to biologically functional differences, and that readings during ASMR itself (along with a machine that doesn't sound like a jackhammer when it is running) would be better.\n\n6. Personality surveys (The Big 5) suggest that the ability to experience \"tingles\" increases with higher levels of Openness-to-Experience and Neuroticism. ASMR participants also had lower levels of Conscientiousness, Extraversion, and Agreeableness compared to non-ASMR controls but this did not scale with intensity of \"tingles\" experienced.\n\n & nbsp;\n\nInteresting stuff, some of it very suggestive, but the state of the research doesn't seem like it's at the cell/molecule-level detail yet.\n\n & nbsp;\n\n \n\n",
"Being a cynic I'd say that the true answer to this question would be identical to the complex chemical processes that relate to happiness or relaxation. Hormones, neurotransmitters, etc. \n\nThat is to say that it is not ASMR that alters one's mood or mental state specifically but the observer who enjoys it, that is my opinion. \n\nIt just seems to be the pseudoscience/wellness meme that's popular right now. \n\n"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
3ikvfm
|
how is recycled steel sorted before melting to ensure that the end product is of a particular grade.
|
Specifically when scrap yards collect different grades of steel/iron (cans, cars, nuts and bolts, cables, furniture, filing cabinets, fencing) are these just melted together, or separated first? Once the resulting product comes out of the furnace, how is the strength then judged to figure out whether it can be used for somthing like food cans or structural parts of a bridge?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3ikvfm/eli5_how_is_recycled_steel_sorted_before_melting/
|
{
"a_id": [
"cuhbtdq"
],
"score": [
6
],
"text": [
"Generally they'll have a rough idea of the composition of each product that they're melting down, so they'll weigh amounts of each item they want to add in, to get to a particular alloy specification (Edit: so to answer your question, yes these things will often be separated out beforehand). Then they'll normally take samples and check what the composition is, and add whatever amounts they need to of pure (or pure-ish...) compounds to get it to the target specification before casting it.\n\nSource: used to work in a lab that did all the testing for an aluminium and a lead recycling plant, I assume its pretty much the same...\n\n"
]
}
|
[] |
[] |
[
[]
] |
|
41c46h
|
flyer miles, other travel things
|
I travel for work. The company books the flight, hotel, everything except for food and incidental expenses. Coworkers have said that they rack up flyer miles and other benefits, and that is why they like to travel. I haven't been utilizing this, as I assumed, to benefit, it had to be from my credit card. Can anyone help?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/41c46h/eli5_flyer_miles_other_travel_things/
|
{
"a_id": [
"cz19qnv"
],
"score": [
2
],
"text": [
"It's mostly automatic, once you've set up a frequent flyer account with the appropriate airline. The miles belong to the traveler, not the purchaser, and a lot of the same information they need to buy your ticket is associated with your frequent flyer account.\n\nIn the event that your trip doesn't show up, there's going to a number or webpage you can go to and request the miles. That shouldn't require much more than your information and some basic information about the flight you took/are taking."
]
}
|
[] |
[] |
[
[]
] |
|
42nhzj
|
why is the us so adamant in having a large global military presence?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/42nhzj/eli5_why_is_the_us_so_adamant_in_having_a_large/
|
{
"a_id": [
"czbmop4",
"czbx1xa",
"czc3b4o"
],
"score": [
16,
3,
2
],
"text": [
"Because the US military underwrites the security of global trade which massively benefits the US.",
"Because not very long ago the world was a very scary place in most places. Big countries like Russia & China & France & Europe and all the others you see winning lots of medals at the Olympics would fight each other. \n\nEverybody wanted more land, or money or sometimes because they didn't like each other. The policies over hundreds of years became political ideologies and formed foreign policies.\n\nThe world got smarter and countries together agreed 'why' they would fight each other. And made many rules. One important one involved allies. A country could and would go to war for an ally. \n\nAmerica was very strong after ww2. While many other countries were weak, in order to continue it required military. So that its allies felt safe which opens up opportunities. To encourage cooperation and to deter aggression. \n\nThe military size was effective, is effective for that purpose. It was not designed for current scenarios. \n\nIf your ok at math if you put 20 peas on a plate. And 17 peas on a different plate. And 3 peas on the third plate. That's how outnumbered Americas military is in comparison to SE Asia n China on a year on year basis. \n\nMeaning if 'they' decided to build an army they could be adding over 9 new soldiers to every 1 new us soldier every year. Technology advances give us a clear advantage. So as long as that's the case it would have an obligation to capitalise on it. Sustainable n for the greater good. \n\nSmall effort, small price now could make huge difference to the future of many nations. \n\nOR \n\nThe US is a war economy?\n\nOR\n\nBecause soldiers need jobs? ",
"Its a number of different factors, all of which have merit but none of which can actually justify such a huge presence. First, it is to secure trade, and thus ensure the US stays one of the wealthiest countries in the world. \n\nSecond, it allows the US to exert international pressure in situations in order to best benefit the US; it makes sense from a purely nationalistic perspective. Thirdly, it has to do with long-term investment; around WW2 the US made huge investments in its military and R & D programs in order to become competitive with the more modern militaries of Britain, France and especially Germany. \n\nLike any investment that pays off over a large number of years, it would simply be bad economics to limit or abandon it after so many years. The payback is not just in international influence but in civilian technology derived from R & D, to some extent the Space Program & its increasing importance in international economics; it makes money, gets jobs in the economy & furthers technology. \n\nHOWEVER, there are some less positive reasons why the US exhibits such a large international presence. One of the primary ones is a sense of tradition; many Americans feel (for any number of reasons, from lack of education to widespread propaganda and extremist rhetoric) that it would be simply \"un-American\" NOT to have a huge military presence. Another reason could be more psychological in nature, with the American psyche (from my experience) centering around the self (or ego), not the community or the big picture, and so its not inconceivable that that personal thought process could find its way onto the international stage and stance on foreign policy. \n\nAs such, while many politicians may feel that the military is too large (as of now representing roughly 50% of the American economy - hundreds of billions of dollars - through a lot of different sectors and whatnot) they can't really do much as the pressure exists in the voting population to have a strong military.\n\nSo yea, basically stuff.\n\nEDIT: formatting"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
1lv5da
|
what exactly does the director of national intelligence do?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1lv5da/eli5_what_exactly_does_the_director_of_national/
|
{
"a_id": [
"cc321et",
"cc341ty"
],
"score": [
2,
2
],
"text": [
"Sort of the boss of the CIA, NSA, etc.\n\nThink of it like this. A company has a pop brand, a chip brand, a cookie brand and a donut brand. All are foods, so they are similar. They are overseen by a CEO (DNI) who helps make corporate strategy between the different brands (each with their own manager) to make an overall strategy.",
"[The south park reference you came here to make.](_URL_0_)"
]
}
|
[] |
[] |
[
[],
[
"http://28.media.tumblr.com/tumblr_m0wuwyRW4Z1rrg9fgo1_500.gif"
]
] |
||
5h0ctg
|
why do the last 4 moths of the year end in ber?
|
Just started to think about it and I wondered if there is a reason
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5h0ctg/eli5_why_do_the_last_4_moths_of_the_year_end_in/
|
{
"a_id": [
"dawe29g",
"dawe7jh",
"daww18d"
],
"score": [
34,
9,
19
],
"text": [
"These months come from the Roman calendar, where they were simply numbered - septem means 7, octo means 8, novem means 9 and decem means 10. They were numbered 7 - 10 because the Roman calendar only had ten months (January and February were added later).\n\nThe exact reason the \"-ber\" suffix is used is unknown. There are two suggested explanations: One is that \"-ber\" is an adjectival suffix, i.e. it is used to transform a word into an adjective, so \"September\" simply means \"seventh\". The other explanation is the that \"-ber\" comes from \"membris\", which means \"a portion / divison\", i.e. \"September\" is short for \"Septem-membris\" means \"the seventh portion [of the year]\".",
"It's from the Latin \"-ber\" which means \"nth\". Therefore\n\nSeptember - 7th month of Roman Calendar\nOctober - 8th month of Roman Calendar\nNovember - 9th month of Roman Calendar\nDecember - 10th month of Roman Calendar",
"Cause they are cold. BERRRRRR. \nI'm actually going to go ahead and say even if this isn't true it is now."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
4wl2fr
|
what is that popping noise your hear when you plug in your headphones and why does it happen?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4wl2fr/eli5_what_is_that_popping_noise_your_hear_when/
|
{
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"d67tndy",
"d67tvgu",
"d67u3pb"
],
"score": [
2,
5,
2
],
"text": [
"I'm not sure of the technicals of it but it has to do with the surge of electricity getting to the speaker when contact is made. The \"pop\" you hear is just a very short burst of white noise.",
"Your music player doesn't know if the headphones are plugged in or not, so the voltage representing the music waveform is always present on the pins of the connector. When you plug the headphones in, the speakers are unpowered and in the 'zero' position. Unless you happen to plug them in exactly at the point that the music waveform is also at 0 volts, the speakers will have to move almost instantaneously to whatever position they're supposed to be in. This happens quickly, and causes an audible click or pop.",
"Commenter one has it closest. \n\nThe \"noise\" is because as you plug the headphones in they are beginning to make the electrical connection. Since there is already voltage present as the connection is being made there is the effect of the changing resistance that causes electrical noise that you hear. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
3ii2vx
|
how does a chinese restaurant kitchen work?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3ii2vx/eli5how_does_a_chinese_restaurant_kitchen_work/
|
{
"a_id": [
"cuglgyi",
"cuglhjw"
],
"score": [
2,
2
],
"text": [
"Worked in one as a prep-cook one summer.\n\nThe key is that everything is prepped well ahead of time. All the veggies and meat are sliced nice and thin, hours before the restaurant opens.\n\nAfter that, they have *insanely* high output burners to get the wok (that's the round-bottomed pan used for stir-frying) super hot. You can cook most things in a minute or two. [Check out this video](_URL_0_) - I can't quite tell what it is (cabbage maybe) but you can see that it's done in under a minute.\n\nThey manage to have so many different items because the same basic ingredients are used in almost every dish, the major difference is just the sauce they add at the end.\n",
"Try /r/cooking or /r/KitchenConfidential "
]
}
|
[] |
[] |
[
[
"https://youtu.be/wmUFhfI_20Q?t=28"
],
[]
] |
||
6ik7w9
|
how can we call or video-chat with someone across the world and sound like we're talking to them instantly?
|
Does this mean that radio waves are as fast as the speed of light?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6ik7w9/eli5_how_can_we_call_or_videochat_with_someone/
|
{
"a_id": [
"dj6w9py",
"dj6wchl",
"dj6wgxa"
],
"score": [
2,
8,
9
],
"text": [
"Yes, radio waves (and all electromagnetic waves) propagate at the speed of light. The communication is in fact not instant, but just very fast. When talking cross-continent, about half the delay is light-speed-based, and the other half caused by processing time in the infrastructure on the way.\n\nStill, pretty impressive that it generally only takes 100-200ms to do so.",
"Yes radio waves travel at the speed of light.\n\nlight and radio are basically the same thing: electromagnetic waves and they all travel at the speed of light.\n\nTelephone and video conferencing communication around the world usually have small but noticeable lag in them because the data that gets send does not travel at quite the speed of light, takes indirect routes and actually spends quite a bit of time inside devices being processed.",
"There is a small (sometimes noticable) delay which we precieve as basically normal conversation. A huge contributor to minimizing this delay is fiber optic technology. It allows information to travel the speed of light while in transit across thousands of miles. Modern processing power and elegant refined networking technology helps ensure the routing bottlenecks are at a minimum. Also data compression algorithms (like Pied Pipers ;) become more efficient which means less information needs to move for every second of video chatting."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
dalii8
|
how do long cars such as limousines get towed?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/dalii8/eli5_how_do_long_cars_such_as_limousines_get_towed/
|
{
"a_id": [
"f1qqdty"
],
"score": [
10
],
"text": [
"You are allowed to exceed the legal length for emergencies. So a tow truck can tow long vehicles to get them out of the road and into the closest workshop. Care must be taken though as the turning radius will suffer. Usually it in enough to just plan the route a bit better and if you need to turn at an intersection it is possible to use more lanes to get a larger turning circle. A problem with limousines and other vehicles is that they are low to the ground and have a bit of an overhang. This means that when you lift one end the other end may go into the ground. This is something that the tow truck driver have to plan for and take into consideration when he is driving. It may be possible to change the height of the lift while he is driving so that he can more easily get over uneven roads.\n\nIf the vehicle can not be towed then it is possible to load it onto a flatbed trailer for transport. In a lot of cases this is the only way to transport them. Vehicles that is too big to fit on a flatbed usually comes apart as they would have been for transport from the factory."
]
}
|
[] |
[] |
[
[]
] |
||
4rlipv
|
people crash after taking stimulants, why does the opposite not happen after taking depressants?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4rlipv/eli5_people_crash_after_taking_stimulants_why/
|
{
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"d525fq9",
"d5263mz",
"d526x22",
"d52gq5r"
],
"score": [
2,
2,
3,
2
],
"text": [
"I think people doing depressants get different withdrawal symptoms, like discomfort and anxiety.",
"On depressants, the crash comes first. Hence forth 'downers' and 'uppers'. The actual crash is only different by symptoms like the rebound of a sensory overload (uppers), or gaining the strength back from a depressed central nervous system (downers).",
"Both depressants and stimulants achieve their effect by increasing the amount of various neurotransmitters (like dopamine, etc.) that are available at the active sites in your brain. Stimulants increase ones that \"bring you up,\" while depressants increase the ones that mellow you out.\n\nAt the same time, the body is always trying to maintain something called \"homeostasis,\" which means it's trying to keep everything on an even keel. So if there's *way too much* of chemical A (thanks to the drugs), your body stops making and releasing its own chemical A - because that would only add to the problem!\n\nAfter the drug wears off, however, you're now stuck in a situation where the drug is gone, and your body isn't making enough chemical A anymore to keep you feeling normal... so you crash. Doesn't matter if it's a stimulant or a depressant - to some extent, you crash.\n\n(there's lots of other stuff involved too, but that's the basic story)",
"As alcohol being a depressent (acting on and inhibiting gaba receptors) , prolonged use and addiction can cause your body to stop producing your natural gaba neurotransmitters. That is why when alcoholics stop drinking alcohol suddenly, they are prone to seizures and other bad stuff because basically the brain is overfirining without anything to \"check\" it's activity. So basically, it does happen, but with more effort "
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
dg5sa5
|
why can gaming pcs run hundreds of fps (frames per second) but no matter what console you have, you can never get an fps number as high as that?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/dg5sa5/eli5_why_can_gaming_pcs_run_hundreds_of_fps/
|
{
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"text": [
"Expensive, high performance parts.\n\nThink of the cost of a console. It’s around the £300-400 mark, thereabouts. You’re not going to build a gaming PC that can play the latest releases at 144FPS for that price. The same goes for a console. Concessions have to be made to keep the cost at a price point consumers want. \n\nThe second problem is that a console’s hardware is set long before it’s released. It could be a couple of years between the hardware specs being finalised and the console hitting the markets. By which point it’s inevitable that the hardware is already outdated. \n\nA third problem is cooling. If you have a console near you, take a look at it. There’s probably not too many vents, and the ones that are there are small. It’s a small form factor, and it’s hard to keep cool. Your average gaming PC has much more space for large fans, heatsinks etc and as such is able to handle the heat of more powerful components better.",
"Consoles are often specifically configured to be limited to a certain number of frames per second, to ensure a consistent experience. For instance, a Call of Duty game running at 60fps might actually be capable of running into the 80's or 90's, but instead of letting the framerate wander around depending on what's onscreen, the developer picks a number they can use as a guaranteed minimum.\n\n\nSome games do have unlocked framerates on consoles, showing exactly this. God of War on PS4 can either be limited to 30, or set to a framerate mode where it will wander from the 40's to the 50's, depending on what's onscreen. I believe the Hitman games have a similar option. Some people prefer the consistency, and some people prefer the refresh rate. \n\n\nAn example of console games going even higher than that:\n_URL_0_",
"A console has known set of hardware and the developer knows exactly what it can do.\n\nThe developer will then make the game to run at acceptable framerate on this hardware (30 fps, 60 fps or something else).\n\nIf the console can run the game at 300 fps the developer will just add more effects, longer draw distance or some other effect that eats performance.\n\nPC can have almost any kind of hardware. The developer will make sure that the game runs on some low end system at acceptable framerate. \nBut if low end system can get 60 fps then high end system can get 300 fps at same quality level.\n\nYou can also play old games on new computers. Consoles can't generally speaking do this. And when they can the game can't usually take advantage of the new hardware properly.\n\nUsually games also have v-sync so you don't get tearing. This will also limit the framerate to the screen refresh rate. On PC you can turn this off if you want to. (\"pro\" gamers do this to reduce input latency. For casual gamers uncapped framerate causes more problems than it is worth).",
"Additionaly to other comments, consoles are made to be connected to a TV.\nYou could make a console game that runs at 144fps, if you traded visual quality for speed, but that would be pointless when most TVs are limited from 30 to 60fps. Some TVs that claim 120fps or 200fps often just add interpolation (getting a 60 fps input and adding between frames an new one made by mixing the previous and next one). So it's not worth pushing for fps when the final result will be limited by the tv. Better to use the cpu ressources to improve graphic fidelity.\n\nAlso, most people are used to 30fps games. Even if TVs can do better than that now, the general public is confortable with 30fps, and if they never experienced better fps, don't even know the difference.\n\nTLDR: why bother pushing console games to 144fps when TVs can't display more than 60 and users don't care?"
]
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34n70i
|
why is mayweather getting paid more than pacquiao?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/34n70i/eli5why_is_mayweather_getting_paid_more_than/
|
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"Because Mayweather says so.\n\n For real. The only way Mayweather would agree to the fight was if it was split 60/40."
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||
a59dd3
|
if every action has an equal and opposite reaction, is the future predetermined?
|
Or put another way, if we had the data for whatever initial event set our universe into motion, would we able to theoretically calculate all future events?
Or put another 'nother way, are the electrical impulses in our brain just reactions in a long chain of reactions from that initial event?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/a59dd3/eli5_if_every_action_has_an_equal_and_opposite/
|
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"This is a bit of an ongoing discussion in physics and philosophy. Is the universe inherently random or \"deterministic\"?\n\nUltimately we're not quite sure if you can predict a system given perfect data. Thus far experiments have suggested that atoms and their constituents have true random motion that would make the universe impossible to perfectly predict accurately, but whether that randomness is innate or simply due to something we can't measure yet may never be clear.\n\nAs of right now, we cannot collect all the data and run a perfect sim on a hypothetical supercomputer.",
"As /u/Lithuim says, we don't know if the universe is deterministic or not.\n\nBut that has nothing to do with \"every action has an equal and opposite reaction\". That phrase is related to the conservation of [momentum](_URL_0_). What it says is that if one body exerts a force on another body, the second body exerts an equal and opposite force on the first body. Or more concretely, if you hit a baseball with a baseball bat, the bat exerts a force on the ball in one direction, and the ball exerts an equal force on the bat in the opposite direction.\n\nIt's possible for that to be true in either a deterministic or non-deterministic universe."
]
}
|
[] |
[] |
[
[],
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"https://en.wikipedia.org/wiki/Momentum"
]
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|
b4w62l
|
does a joint's ability to be cracked say anything about the health of the joint?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/b4w62l/eli5_does_a_joints_ability_to_be_cracked_say/
|
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"I have vEDS. A genetic connective tissue disorder that affects all the joints in my body. Every one of my joints snaps crackles and pops abnormally. So yes, excessive cracking CAN be a warning sign, but some cracking or popping is completely normal.",
"No, but it may (possibly) say something about the health of the individual. \nRegular knuckle “cracking” is the popping of gas bubbles in the joint, and has for a long time been said in an old wives tale that it causes arthritis.\nThere was one doctor in particular who cracked the knuckles on one hand for a long time and not the other and found his hands both ended up the same. Another big study confirmed this later.\nInterestingly there was a study done in 1990 that showed that people who cracked their knuckles may be less healthy overall in that they were more likely to smoke, drink and have lower grip strength. It does not mean that cracking the joint is harmful, but perhaps done more frequently in anxious people, for example.\n\nEdit: probably too many big words for most 5 y/o",
"Doctor of Physical Therapy here. The crack you hear when you 'pop' a joint (called cavitation) is simply nitrogen bubbles being released in the joint's synovial fluid from the negative pressure of the joint being stretched. Quite normal, and not unhealthy. I use joint manipulation with my patients often as a method of pain relief.\n\nI tell my patients, \"healthy joints crack, pop, and can make sounds, and that doesn't mean your joint is unhealthy or unstable\". For example, every time I squat down, both my knees always loudly crack. Never had knee pain, and it's totally normal. ",
"A joint cracking/popping can be caused by a wide variety of things such as tight muscles or sleeping funny. As long as the cracked joint doesn’t cause pain, there shouldn’t be any concern. There are more poppings when we get older because of loss of cartilage that acts as a cushion at many joints. ",
"I have double jointed feet, means I sprain my ankle often, and VERY BADLY. Recently went to a chiropractor, realised so many more of my joints are hyper flexible too, which explains the constant need to crack my shoulders, elbows, hands, legs and neck, and spine. This isn't fun, I have to crack my joints or they start feeling uncomfortable. Recently started waking up with my right hand popped out of place every morning, which was incredibly painful, and I had to slowly try pop it back in place every morning. Also my spines started bending so much that it's started trapping nerves ",
"Hi! Chiropractic student here.\n\nELI5: The short answer is maybe. Being able to \"crack\" or \"pop\" most joints is very normal and finding that you can no longer crack a joint that you once could because now it hurts too much or just won't move, OR that a joint is cracking often without you doing it could maybe mean that the joint is unhealthy. But it is not enough information to say that there is 100% something unhealthy about it. Some people are very bendy and the fact that they can move around so much is enough to make their joints go pop on their own. \n\nELI25: The cracking sound that is heard when a joint is manipulated is known as a cavitation, or more recently, tribonucleation. Until very recently, the medical community believed that the sound was caused by the collapse of gas bubbles within the synovial fluid found in synovial joints (such as a finger joint). However, recent findings suggest that the sound is actually made when a bubble (or cavity) is formed within the synovium. The theory suggests that joint surfaces resist separation until a critical point (when we hear the cracking sound) when they separate rapidly creating sustained gas cavities. \n\nA great resource to support this is the MRI imaging study \"Real Time Visualization of Joint Cavitation\" by Kawchuk et al. (2015)\n\nThe benefits of joint cavitation range from decreased joint pressure, restored/increased joint mobility, to even just psychological satisfaction of hearing the cracks. \n\nThe ability to cavitate a joint is a normal part of joint health, and can be useful data in determining the health of the joint. Not being able to do so, either because of pain, inflammation, stiffness, stickiness, numbness, etc. can be an indication that the joint is injured, unhealthy, or on its way to becoming unhealthy. However it is simply not enough data to make that diagnosis. Conversely, a joint that cracks every time it is moved can be a sign that the joint is unstable, or it could simply indicate a healthy joint that happens to be hypermobile (which is a normal finding), increasingly flexible, or just average. The point is that yes, a joint's ability for cavitation can provide us with data about the health of the joint, but we should never make assumptions about the health of a joint based solely on that information. ",
"I remember seeing an example on TV about this once.\n\nSomeone took an empty Pringles canister and heading up the bottom. They opened the cover and there was a loud, audible pop. He then showed everyone the inside, and it wasn't damages at all.",
"In my experience a joints ability to crack says much more about how long it's been since I last cracked them",
"What if you have never been able to pop a joint. I cant crack my knuckles or wrist but every now and then my knees will pop and it's not very good feeling. Am I a alien? ",
"Peter attia just did a email on this subject exactly. \n“Greetings -\n\nDuring my boxing days (not egg boxing, as I remain current in that endeavor) I had an obsession with cracking my knuckles. How the heck does it produce such a cool sound (people around me beg to differ on the degree of coolness)? I also often wondered if I was doing irreparable harm by doing so. \n\nEnter an interesting article from the New York Times (2018): Why Do Cracking Knuckles Make That Noise? You Might Need a Calculator. It turns out a couple of researchers created a mathematical model of a cracking knuckle, and it suggests that an old theory—the sound arises from the popping of a bubble in the joint—could accurately explain the knuckle-cracking sound.\n\nAs far as harm, will cracking my knuckles give me arthritis? Probably not. A 2011 case-control study examined the hand radiographs of 215 people and compared the joints and found no difference between crackers and controls...no matter how many years or how often a person cracked their knuckles. And how about this for an n=1 experiment prize (I like knowing I have much to do to earn my n=1 chops): \n\n“During the author’s childhood, various renowned authorities (his mother, several aunts, and, later, his mother-in-law [personal communication]) informed him that cracking his knuckles would lead to arthritis of the fingers. To test the accuracy of this hypothesis, the following study was undertaken. For 50 years, the author cracked the knuckles of his left hand at least twice a day, leaving those on the right as a control. Thus, the knuckles on the left were cracked at least 36,500 times, while those on the right cracked rarely and spontaneously. At the end of the 50 years, the hands were compared for the presence of arthritis. There was no arthritis in either hand, and no apparent differences between the two hands.”\n\nIt has also been suggested that people who crack their knuckles were more likely to have lower grip strength: but recent experiments (here and here) appear to refute this.\n\nVery cool topic and research combining myth, math, medicine, curiosity, and the quest to know more. Crack away...\n\n- Peter\n\nFor a list of all previous weekly emails, click here. (Not really since its a copy n paste)",
"I had my joints crack for years now, but 4-5 years ago I developed a rare bone disease & chronic joint + bone marrow inflammation. Is me cracking my joints left & right by just walking or standing fine when it doesn't cause pain? (other than stretching them too much) ",
"I know I’m not the only one that read this and immediately started popping everything I could. "
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49u1at
|
why is iran ramping up missile tests so soon after the nuclear deal was struck?
|
Even though it's not technically a breech of the terms of the deal, it seems to me that this harms their credibility in actual adherence.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/49u1at/eli5_why_is_iran_ramping_up_missile_tests_so_soon/
|
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"Their credibility was never in question actually, the US credibility was. Iran had long been making better nuclear offers that the US rejected in favor of an imposed regime-change agenda.\n\nIran's nuclear program was always quite legal, with absolutely no evidence of an actual nuclear weapons program found there, ever.\n\n_URL_1_\n\n_URL_3_\n\n_URL_0_\n\nThe US only accused Iran of seeking a \"capability\" to make nukes, which more than 40 nations already have because it is inevitable in having even a civilian program (any technology \"could be used\" to male nukes)\n\n_URL_2_\n\nThis was all just another case of \"WMDS in Iraq\" hype promoted by the Pro Israeli lobby in the US to try to cause a war with Iran, just as \"WMDS in Iraq\" was just a lie and pretext\n\n"
]
}
|
[] |
[] |
[
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"http://mobile.reuters.com/article/idUSTRE58G60W20090917",
"http://www.theguardian.com/commentisfree/2011/jun/09/iran-nuclear-power-un-threat-peace",
"http://old.seattletimes.com/html/nationworld/2002041473_nukes21.html",
"http://mobile.reuters.com/article/idUSL312024420090703"
]
] |
|
37ef60
|
would a car going 60mph rear ending a car going 59mph have the same impact as a car going 1mph rear ending a stationary car?
|
Also would a car going 100MPH rear ending a car going 99MPH have the same impact as a car gong 10MPH rear ending a car going 9MPH?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/37ef60/eli5_would_a_car_going_60mph_rear_ending_a_car/
|
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"The actual impact force would only be a 1MPH impact but that could quickly spiral out of control if spooks the driver or causes the car to lose control. \n\nCars probably aren't the best thing to look at because there's so many other factors involved beyond \"thing A hits thing B\". If you look at something simple, like hockey pucks on an infinite sheet of ice, then, yes, the physics works regardless of the speeds of the objects involved.",
"Essentially yes, with one big difference.\n\nThe relative velocity is the same in all three scenarios so the energy transfer would be the same.\n\nA minor collision can cause loss of control at speed though. If the car loses traction at 100 mph due to a minor bump a serious crash may result.",
"For the purposes of explaining this to a five year old, the answer is YES. Motion is all relative. So in the direction of the movement of the cars the difference in relative speeds of the two cars is all of these scenarios is 1 MPH. One easy example of relative speed is imagining this happening with two remote control cars in a first scenario on a stationary people move and in a second scenario on a moving people mover going 10 mph.\n\nSome things that complicate this and make the answer no include different frictions at different speeds caused for example by air resistance (which is speed dependent) and the transmission of the car. \n\nAlso, if the rear ending causes the car to change course the outcomes would be different. If the 1 mph bump causes the car to turn 1 degree left the faster car would deviate from its original course much faster than the slower car. ",
"Assuming the cars are the same mass, the force of an inelastic, or elastic collision between the two cars would be the same in both cases. ",
"Yep, same thing. Keep in mind we're all on a ball hurtling through space at 67,000 miles per hour. If the force of a collision wasn't tied to its frame of reference and somehow just reflected the absolute speeds of the objects involved, every step you took would be cataclysmic. \n\nEDIT: Tense correction for 'took'.",
"Is the stationary car in Park?",
"Pretty much yea. I fell asleep at the wheel going 70 mph one day. The impact of catching up and rear ending the car in front of me woke me up. No damage to their car and some minor damage to mine. Thankfully nobody hurt and thankfully I kept the wheel straight. ",
"Just recently got hit by a semi going 71 mph but luckily I was going about 70, so the damage was surprisingly minimal.",
"I would guess that while the total force of the crash is the same in both cases, the stationary car would take (slightly) more damage since the axles would need to overcome static friction before the car moved forward. The moving car is already in kinetic friction, so the impact would be translated into acceleration rather than deforming the bumper.",
"i disagree with top post, 1 mph impact at 0 mph will have more deforming power than 1 mph impact at 10 mph because inertia of the wheels. \n\nThey will be harder to turn to 1 mph than to 11 mph, and this will cause (little bit) more pressure on the end of the car.\n",
"Yeah I'm going to have to disagree. the stationary car would have to be in neutral or not on the brakes in order for it to be the same...Think of it like this... NASCAR bump drafting, or hitting a concrete wall. That is an exaggerated version of both. While in the terms of physics... Both masses and velocities calculated the impacts would probably be similar..but in the real world, if a car is stationary it's usually either in park, or brakes are applied. Energy from the impact would be less likely to be transferred into forward motion as hitting a moving car. HOWEVER, if the 59mph car was decelerating as fast as it could, And hit by the 60mph car, the impact would be greater. It's about the transfer of energy more than anything. ",
"A real world example of the answer to your question would be a NASCAR race, especially at tracks like Daytona and Talladega. \n\nSpeeds are on the order of 200MPH and it's common place for the drivers to make contact by either bumping front to back or side to side. Sometimes they'll make contact rather hard, probably a delta of more than a few MPH, which is known as Slam-Drafting and it's looked down upon as it's dangerous.\n\n_URL_0_ ",
"Transfer of energy would be the same, but the amount of kinetic energy of two objects in motion is much higher.\n\nIf my high school math serves me well, let's assume there are two trains leaving their stations at different times.\n\nTrain A travels at 100mph. Train 2 leaves the station a minute later traveling at 12,000cm/sec. If they both occupy the same space, on the same track, the cute girl next to me has really nice boobs and I failed math class. ",
"A cartoon had a episode like that, I believe it was called something like Jake The Dragon, ? I could be totally wrong and they had a episode were he was flying and a boulder was about to smash into him but he was at 59 speed while the Boulder was at 60 so it didn't do any serious damage. ",
"Kinetic energy equation is: E = (1/2)m*v^2\nA few simplifications:\n1. Let mass (m in the equation above) = 1\n2. Let the velocity of the car after the collision to be the velocity of the slower car.\n\nAssuming v1 = 60 and v2=59, then the change in energy from 60 MPH down to 59 MPH is (1800 - 1740.5) = 59.5 units of energy.\n\nNow, the difference between 1 MPH and 0 MPH:\n(1/2)(1)(1^2) - (1/2)(1)(0^2) = 0.5 units of energy.\n\nSo you have to get rid of 119x more energy in the faster collision. So it does more damage.\n\nEdit: But this goes against nearly every other comment in this thread, so it's very possible I'm wrong. But someone tell me why.",
"Because of newton and his pesky laws, there would be a difference between the car at rest compared to the two cars in motion, the car at rest would receive more energy based on the wheels being in place. ",
"Id say no. if the car is parked, the tires are locked and thus the car will not move (or move very little).\n\nThe moving car is not locked, and will likely speed up slightly form the impact. less overall damage.\n",
"Yes because of the principle of relativity. It's not possible for an observer moving at constant velocity to tell that he is moving. In his reference frame the car is moving backwards towards him at 1 mph which is the relative difference in speeds.",
"I'd say the instantaneous impact would be the same. But then again physics has a way of making you feel comfortable about your answer then violently fucking you in the ass.",
"It really depends on what you define as \"impact\".\n\nIf both cars are traveling through space, not on a road, there's zero friction, and no other factors besides the cars' speeds, then yes, it would feel exactly the same, and the force exerted would be exactly the same. I believe this is called \"impulse\" in physics... I could be wrong, though.\n\nWhen you're in open space like that, and there are no stars around for a million light years, you really have no reference point for motion anyways. Here on earth, we say we're moving 0MPH right now sitting on our asses posting to reddit, but in reality, the earth is moving very quickly through space. So is the sun, the solar system, and our galaxy. So in open space, all that you can really measure is *relative* velocity/speed, because you can pick any one of an infinite number of reference points. If you were out in space, you'd have legitimately no way of knowing which scenario it was. You'd also be royally fucked, because you're in an automobile, in space. You'd be dead.\n\nHowever, if you're talking about on a road, and define *impact* as what happens when the cars hit each other, then no. The parked car that got hit would not move forward, because it's parked and has it's parking break on. However, the cars going 59 and 60 MPH would collide and both (assuming they weigh the same, have the same level of friction, et cetera) would be going 59.5 MPH after the collision, so the disbursement of the collision would be different. Also, a car going 99MPH has very little room for error and if that bump caused a loss of control, errebody gon die.\n\nEdit: Also, I know that's a simplification - the parked car would probably move a little. But if we change the example to a 10MPH difference, you can see what I'm saying - hitting a stationary car who's wheels are locked is different than hitting a car who's wheels are turning freely and can absorb some of the shock.",
"You need help with homework there timmy? ",
"Two special factors come into play when you involves a stationary car: Static friction and if its in neutral or not. Otherwise its the same. 2 mph hitting 1mph is the same as X mph hitting X-1 mph.\n\nStatic friction describes how difficult it is to start sliding something, whereas \"regular\" friction describes how difficult it is to slide it once its already moving.",
"As other people have explained, the relative impact and energy transfer will be the same. Let me ELI5 how though. \n\nFor the 1mph accident, imagine you're a linebacker about to start the down. You're in position, three point stance, ready for play to start, when the guy opposite you pushes you in the shoulder. You feel the impact, but you don't fall over and it does very little damage. Similarly, a stationary car won't feel much of an impact. \n\nImagine the 100mph accident. You're now a ballerina - up on the tips of your toes, arms up in the air. The same person opposite you now pushes you in the shoulder, with the exact same amount of force as last time. There's now a fair chance you're going to fall over, unless you precisely correct your balance. The reason seems quite obvious, no? Before you had a stance with a lot of balance and grip, and now you had a stance with very little balance or grip. Driving a car is the same basic principle - the faster you're going, the easier it is to lose traction, lose grip and have an accident. So while the impact itself is relatively the same, it's differences in how you're able to absorb that energy and balance it out that make the 100mph impact far more dangerous. ",
"Yes, for one simple reason: there is no privilaged reference frame. Imagine you're on a train, and you throw something at the wall. The speed the train's moving doesn't matter, since it's moving _with_ you. The force comes from how hard you can throw, relative to the train.\n\nSimilarly, the 100mph car hitting the 99mph car will be exactly the same as a 1mph car hitting a 0mph car while they're both on an aircraft carrier moving 99mph, which is in turn the same as if you just did it on land.",
"The basic answer is yes.\n\nThink about it like this: if I was riding an airplane with you, and punched you, would it feel like I hit you with an airplane? No, because although my fist would be moving over 500 mph, so would you. Thus, it's all about relativity.",
"If you throw a ball at someone at 50MPH and it hits them in the head; does it matter when it hits them the ball is also traveling at 67,000MPH relative to the sun (in the earths orbit of the sun)? No. Just that relative to the other person's head, it is traveling at 50MPH.\n\nIf the 2 cars are going in the same direction; relative to the 99MPH car, the 100MPH car is approaching at 1MPH..\n\nThough the potential for the cars that are moving at 99 or 100MPH to lose control could lead to much greater damage than a car moving at 9 or 10MPH relative to its \nsurroundings..",
"Yes and no.\n\nIf we only consider the two cars, then yes, the impact is the exact same.\n\nBut we have to consider the ground. Even though the ground isn't moving, to someone inside the car (and the car itself) *it seems* that the ground is moving back really fast, and the car is not moving at all. And no, we can't ignore the ground, the cars can only reach the speeds they do by pushing their wheels on the ground.\n\nSay that both cars crash and the one on the front goes half a mile faster because of the push, and the one on the back goes half a mile slower because of the crash. In the first example the cars would be going at 99.5 MPH, or well to them the ground would be moving backwards at 99.5MPH. In the second case it would be moving at only 9.5 MPH.\n\nAnd how does this change things? Well think of yourself on a treadmill running, and then someone pushes you. If the treadmill is going slowly you probably won't have much trouble, but if the treadmill is going really fast and you're at top speed you probably are going to get hurt, badly.\n\nIn short: when you crash it's not just the other car that is pushing and moving you, but also the ground (that could even send you off flying) and the ground is \"moving\" at different speeds in both examples.",
"It's not entirely the same, but there's a cool video showing the concept of velocities cancelling out.\n\nOn mythbusters they shot a ball at 50 mph out of the back of a truck travelling at the same speed. The result is that the ball just appears to drop vertically downwards when observed by a stationary bystander:\n\n_URL_0_",
"In a similar context, given a (really strong-legged) person that can jump up at 50mph is stuck in an elevator that's falling down at a rate of 51mph, if the person jumps up in time right before the elevator hits the floor, would he/she survive?",
"If you think about it, at the equator you're already going 1,040 mph just from the earth's spin. So a 1 mph collision is a 1,041 mph object hitting a 1,040 mph object. A 59 vs 60 is a 1,099 object hitting a 1,100 mph object. Same. Except for the whole relative speed to the ground, traction, car control etc. issues.",
"The answer is: yes, assuming that the stationary car is not \"stationary\" in the sense that it cannot move. The kinetic energy released onto the moving car would be the same as the kinetic energy released onto the stationary car because it is the relative difference in speed that counts and the relative difference is the same in both instances. The answer is the same in both questions. The reason for this is that \"speed\" is always relative to one object versus another object. Also, the formula given below for KE is incorrect. KE = mass x velocity squared divided by 2. \n",
"If you want to know what cars do when they touch at those speeds, watch NASCAR. NASCAR may have faster speed but same principle applies. ",
"Question: wouldn't the rolling impacts actually be less, because they have inertia already going in the direction of movement? So the excess energy of the impact causes an acceleration in the direction of movement, rather than having to create that movement? It seems like less energy would be transferred, over all, because the 'impactee' is already moving.\n\nIn my head, it's the difference in hitting a brick wall at 1 mph and hitting a ball at 1 mph. One moves, the other doesn't. But I haven't done physics in like 10 years, and I was shit at it then too.",
"it would be a minor bump...clarkson bumped hammond and may in his transit doing pretty much the same speed and nothing happened except a small dent",
"I rear ended an SUV. I was going 63 MPH and the SUV was going 20 MPH. It was a dead on collision in the rear. In which I pushed the SUV about 10-15 feet. I weighted 5200lb and the SUV 6200lb. I am curious about the force of the impact if anyone can answer. I feel so lucky to be alive. And thankful no one was injured besides an ankle sprain I'm still dealing with 6 months later. I don't remember what caused me to crash. I would drive 150-200 miles per day with the job I was working. No matter how well you think you can drive. You always need to be alert 100% of the time. Is the lesson learned.",
"Now here's a fun one. Car is going 75mph and hits a pebble, at what angle does the pebble bounce after the tire goes over it?",
"Yes, the damage from one car contacting another would be the same, because the speed relative to each other is all that matters. However, their speed relative to the ground, which they are in contact with, is still much much higher at 99 MPH than at 9MPH, so the real problem with it is that a small tap could cause you to crash into something on the ground, again, moving 99 MPH less than you.",
"Basically, same impact, but the different momentum/s at speed could cause loss of control. If so, just do a handbrake 360, fire a grappling hook into a overpass, flip over it like a auto trapeze gimp while giving the thumbs up to Vinny D and you'll be sweet.",
"If the stationary car has its brakes on in the collision will be very different than two cars at speed. Iirc this is an example of an elastic versus an inelastic collision",
"In the second scenario they would both end up in 1985. Accounting for the speed/time differential (they would hit 88MPH at different times) I believe the trailing car would teleport first, thus making it impossible to actually rear end the car in front of him.",
"It would be the same impact, but it would be more dangerous because even a small impact can make you lose traction, which at high speeds could cause a really bad crash.",
"Impact would be determined by the change in momentum. Change in momentum depends not just on the initial velocity but the final velocity also. Thus if the car that bumps is going at 60 mph ends up with a speed of 59 mph, it will have the same impact as the one going at 1 mph ending up at 0 mph. If however, the 60 mph ends up at 0 mph, the impact would be greater than the one which goes from 1 mph to 0 mph.\n\nBasically, change in velocity(final - initial) will determine the impact. Initial and final velocities themselves do not matter. Mass also counts but here let us assume all cars have the same mass.\n\nThe top answer is wrong.",
"If you want a easier question. If a spacecraft in orbit is going 7800 m/s (17,450 MPH) and another spacecraft is catching up behind it with a speed 7,801295 m/s (17,451 MPH) and bump into it it would be exactly like a 1 MPH collision. \n\nIt gets tricky when you add in traction, friction, control that you have while in a car. But in space where you have non of that that would be that exact case.",
"The velocity of any given object can only be determined when comparing it's movement in space to something else. Nothing has \"absolute\" speed, speed is always measured relatively to something else. \n\nSitting in the second car, you will always observe that the first car is moving at 1mph towards you, and that's all that matters at initial contact.",
"Now, on the other hand, you know those movie stunts where a car drives up a ramp into the back of a moving semi, or ejects from the rear of said semi onto the highway?\n\nDon't try it.\n\nScenario 1: Truck's doing 60 on I-81, ramp is down in the back. You do 63 behind the truck and glide nicely onto the ramp. So far so good. But after your rear tires hit the ramp, you're still doing 63 MPH on a now-stationary surface, so you have about 20 feet to screech to a stop before ramming the front wall of the trailer. Good luck with that.\n\nScenario 2: Truck's doin' 60, you're in the trailer, inside your car. You back down the ramp at 15 MPH in reverse, and hit the tarmac. So are you now tootling down the road doing 75? 60? 15? Answer: Well, son, you're now on the highway, doing somewhere between 0-15 IN REVERSE (depending on your momentum factor), and gawd help you if there's another car on the road behind you.",
"There's a factor missing from these responses: a stationary car would have no inertia, as well as likely brakes applied to remain stationary. It takes more energy to go from 0-1 than it. does from 59-60, therefore there is more resistance in the stationary car, again especially assuming that brakes are applied.\nThink about it this way: ever try to push a car out of a ditch or snow? What's the hardest part? Just getting it moving that first little bit, once it has inertia it is easier to accelerate.",
"Ever watch nascar when they bump into each other?",
"Theres one thing alot of people are forgetting. The resistance of the vehicles to move. \n\nIf yiu hit a stationary vehicle its like hitting a wall, but hitting a moving vehicle going the same direction is like hitting one of those football tackle practice dummies. \n\nAt 1mph the difference is probably unnoticable but at higher speeds there will be a significant change in damage.",
"OP, why so timid? have one car going at 1000MPH and the other at 999MPH",
"The answer is YES(I think). Under some conditions.\n\n The road surface must instantaneously become ultra low Friction (like wet ice rink nascar) upon the point of impact also the side-rails must go subjects relative speed. \n\n There's something I'm missing in the reactive Friction vs the tires' traction. Oh yea, it's how mass,velocity and inertia between two objects pisses me off with math...... \n **Shit** you just meant the initial impact Damage didn't you? The answer is still yes since we are only examining the damage of the **'First'** impact peck from the first car to the other and **not** the ensuing reaction of velocity or secondary impacts. \n If both cars are Identical, you only measure the **initial** impact data then yes.(?)\n If cars have different mass then I (ignorantly) say NO, the potential outcome would depend on combos' with Front/Back Light/Heavy. ",
"Yep, in fact I tested this on an actual road. Or rather a guy I worked with who was driving behind me decided to test it. Drove into my truck with his (intentionally) going a couple mph faster than me, scared the crap out of me, but ultimately no issues. We were going around 35-40 or so.",
"If the stationary car was in neutral the forces would be similar, but the moving car would always take less damage as it can translate that force into motion easier as it is already IN motion. Even in neutral you'd have to overcome the inertia of the stationary car. A parked car in gear or with the EB on, would have to overcome much more friction from the tires as they can't roll. \n\nOR Yes, but only for spherical Chickens in a vacuum. ",
"I'm not sure about that but... Isn't the violence of the impact linked with cinetic energy?\nIf so, the difference between 1km-- > 0km/h is not the same than the difference between 60-- > 59km/h as the cinetic energy is proportional to V².",
"This answer is no they will not be the same impact. The effects of a crash are directly related to the difference in kinetic energies of the cars, not the difference in speeds. Each car's speed contributes to its kinetic energy, but you cannot just subtract each cars speed to arrive at the same thing. \n\n\nThis is because kinetic energy goes with the square of speed. So, even if you are maintaining a constant difference in speed, the kinetic energy difference will get larger and larger as the two speeds go up. ( 2^2 - 1^2 < 3^2 - 2^2 ).\n\nEdit: Downvoted for being too right? People just can't take it when something is exactly correct? ",
"Based on your question Im going to assume you are asking about the impact and not about loosing control of your car. With that in mind you are correct there is no real difference. Watch [THIS](_URL_0_) video pf beginners skydiving. They are falling at ~ 120mph and bumping into each other. As their relative velocities are small they are unhurt. If how ever they were to impact, at that speed, a skydiver who had already opened their parachute 1 or both would likely die. ",
"This should be in /r/askscience because most of the answers here are from people whose math skills peaked in high school.",
"Almost everyone who answers this forgets what car people consider obvious. \n\nThat is, a moving car is already moving. In other words, the drivetrain and brakes are open for movement. \n\nSo, my answer is No. It's not the same. \n\nThink of it like this. \n\nThe vehicle impacting a stationary vehicle has to overcome the traction of the tires. \n\nThe vehicle impacting a moving vehicle is hitting something already rolling and able to more easily roll more. ",
"The impact *forces* would be the same, but the overall *effect* would be much different. At 100mph, it doesn't take very much effort to cause you to lose control of your car, resulting in a terrible accident. At 10mph, you can immediately regain control and safely come to a complete stop.",
"Other have pointed out the problem with losing control at high speed. So let's even the playing field by considering trains instead. If a train going x mph rear-ends a train going (x-1) mph, the damage is about the same regardless of the value of x.",
"As sometimes seen in car races, minor bumper rubbing makes little difference as long as everyone keeps their car pointed in the right direction... \n\nHarry Hogge: Cole, you're wandering all over the track!\n\nCole Trickle: Yeah, well this son of a bitch just slammed into me.\n\nHarry Hogge: No, no, he didn't slam you, he didn't bump you, he didn't nudge you... he *rubbed* you. And rubbin, son, is racin'.\n",
"Relativity. It all depends on relative speeds, not absolute.\n\nThey would have they same effect, yes (though the 100mph collision would probably end worse if one of the drivers reacts badly).\n\nNo matter how fast you are going relative to the observer, the collision speed is always relative to the moving objects in question.",
"No, A parked car wouldn't move and the there would be more of a bent bumper. If both cars are already in gear, there would be a lot less damage to your bumper, since both cars will still be moving. I've been given a love tap going 75 before by some jackass behind me. It wasn't as bad as other comments make it seem. I think people will probably over react jerk the steering wheel and crash the car themselves.",
"Yes.\nThe only difference being the person you rear-end will claim all sorts of back/neck injuries and tell the the cops you hit them going 60",
"No one seems to be mentioning that when you hit a parked car, the energy is not transferred effectively since the cars brakes are ok... therefor your car gets fucked up. \n\nNot deadly going 1 mph or anything, just costly \n\n"
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"https://www.youtube.com/watch?v=86P063Y9-oo"
],
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[]
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|
lso8l
|
why the country with the most muslims is located in indonesia.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/lso8l/eli5_why_the_country_with_the_most_muslims_is/
|
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"Arabs came in boats 1300 years ago. Indonesia has like 250 million people",
"\"In\" Indonesia? Indonesia itself is a country. It was part of a huge Muslim trade network that stretched from east-Congo to Malaysia. People living on Indonesian islands converted for various reasons. \n\nIn 1603 people from a new and tiny Republic came along and subdued the various tribes on various islands. They turned it into a single colony called Nederlands-Indië and when the natives population became independent 344 years later they decided to stick with being one country (and forced the unwilling to join).",
"Don't forget, there are 150 million or so Muslims in India. Most of the places the muslims conquered just didn't support very high populations, unlike SE asia.",
"Why wouldn't that be true?\n\nBrazil's got lots of Catholics, what about it?",
"Arabs came in boats 1300 years ago. Indonesia has like 250 million people",
"\"In\" Indonesia? Indonesia itself is a country. It was part of a huge Muslim trade network that stretched from east-Congo to Malaysia. People living on Indonesian islands converted for various reasons. \n\nIn 1603 people from a new and tiny Republic came along and subdued the various tribes on various islands. They turned it into a single colony called Nederlands-Indië and when the natives population became independent 344 years later they decided to stick with being one country (and forced the unwilling to join).",
"Don't forget, there are 150 million or so Muslims in India. Most of the places the muslims conquered just didn't support very high populations, unlike SE asia.",
"Why wouldn't that be true?\n\nBrazil's got lots of Catholics, what about it?"
]
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||
sdirm
|
the lingo and practical application of twitter
|
Forgive if this has been done before...I did try to search, but didnt find a thread.
..and I should say, I feel sorta foolish...but what the hell...
Anyways, I have a twitter account, and I'm signed up to follow about 6 people, but I really don't know what I'm doing.
What does it mean when someone says something is trending? What is the hash tag "#", and what does it mean in front of a word? What does it mean when someone uses the "@" symbol in a tweet?
For example...I follow Neil DeGrasse Tyson...when he sends a tweet, does everyone get the same tweet? If I simply reply to this tweet, does he see it?
Thanks in advance.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/sdirm/elif_the_lingo_and_practical_application_of/
|
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" > What does it mean when someone says something is trending?\n\nA trending topic would be something a lot of people are tweeting about at once. For example, February 14th is Valentine's Day, so on that day Valentine's will probably be trending, as well as other terms related to dating and romance and candy and roses.\n\n > What is the hash tag \"#\", and what does it mean in front of a word?\n\nHash tags can mean a lot of things. Hash tags are searchable, so if you want to tweet about, say, the Emmys so that people can see it, you might say something like \"Watching the #Emmys, [remark you want people to see]\".\n\nHash tags are also frequently used as sort of meta comments about the tweet - like you could say something like \"Just took my last final #college\" or \"Standing in line at the DMV #fml\", and those hash tags would be kind of a way to interpret or understand the tweet they're a part of. It's actually a very interesting way to use language.\n\n > What does it mean when someone uses the \"@\" symbol in a tweet?\n\nTwitter handles are always @[name], so when you see someone tweeting @soandso, they saying something to another person on twitter. So if this were twitter and you'd want to say something to me, you would tweet \"@office_fisting_party, [message]\".\n\n > when he sends a tweet, does everyone get the same tweet?\n\nYes.\n\n > If I simply reply to this tweet, does he see it?\n\nThat would depend on how he is looking at Twitter. If he's just tweeting from _URL_0_ he might miss it if he has a lot of followers. There are twitter clients that notify you if someone tweets at you, so he might see it if he's using a client. I have no idea how this works on smartphones or tablets.\n\nAs far as practical application goes, I've seen four main uses for Twitter. The first is for breaking news - because it's real time and limited in characters, the application lends itself to blurting out headlines as soon as they occur. The second is for jokes. There are a lot of accounts out there that mostly or only tweet funny things, or at least things that the user thinks are funny. Third is for broad social networking purposes, sort of like Facebook. Maybe you found a cool link, or you have an interesting thought to share, or maybe you just want to shout something into the void. Finally people use Twitter for marketing and personal promotion. \n\nhaha wow I never thought I would write so much about Twitter. I hope this has been informative!"
]
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[] |
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[
[
"twitter.com"
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|
5vr9kt
|
why do all utf-8 html codes start with an ampersand?
|
Why is the character to tell your browser about an UTF-8 code an ampersand and not any other character?
& nbsp;
Such as & amp;eacute; or & amp;#3792; etc
& nbsp;
EDIT: I had to use & amp;amp; because Reddit seems to autotranslate these codes
& nbsp;
EDIT2: OK, the question was ambiguous. I wonder why it is **specifically** an ampersand.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5vr9kt/eli5_why_do_all_utf8_html_codes_start_with_an/
|
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"Because the ampersand is what signals the browser to treat the next sequence as a UTF code and not as just a literal string of numbers and/or letters. You need something to cue to the system to read that code in a different way or it would just print the thing you wrote and not the thing you wanted. ",
"No particular reason. They could have chosen any character in the table. But it had to be readable, easily identifiable, it had to be on most keyboards, it shouldn't be widely used, not any other char with html meaning already, etc. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
11cddb
|
logarithms, the natural log and euler's number.
|
So, this is slightly embarrassing as I am actually in a calculus class this semester, but I have never been able to quite wrap my head around these three concepts. I'm fine with exponents, and square roots, and even higher roots, but for some reason these things just escape me. When I see the symbols on my homework I can generally manipulate them into something that gets me credit for the question, but I don't really understand what's going on in the same way that I do with, say, division.
So, what exactly is a logarithm? What does it mean to "take the log" of something? How is a "natural log" different a "regular log?" And where does Euler's number (e) fit into all this? I know they're related, but I don't know how.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/11cddb/eli5_logarithms_the_natural_log_and_eulers_number/
|
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"Let's talk about e first...\n\nThe number e (~2.7182818...) is the number you get when you take the limit as n goes to infinity of (1 + 1/n)^n.\n\nA good example of the application of e would be something called \"continuously compounded interest\" in banking. \n\nWhat is continuously compounded interest? Glad you asked.\n\nSuppose you start a new savings account with an initial deposit of $1.00, and you get 100% yearly interest. If you only compounded the interest once at the end of the year, you would have $1.00 + 1.00x100% = $2.00. If you compounded it twice during the year we would get $1.00 + 1.00x50% = $1.50 for the first compound and $1.50 + 1.50x50% = $2.25 at the end of the year.\n\nNotice how even though the yearly interest is the same, we get different amounts of money at the end of the year depending on how many times we compound it. Also notice that this pattern exactly matches the relationship I mentioned earlier (1 + 1/n)^n, where n is the number of times we compounded interest during the year.\n\nTo continuously compound interest means to literally compound interest an infinite number of times during the year (n approaches infinity). 'e' is called Euler's number because the Swiss mathematician Euler figured out that this limit approaches 2.7182818... (Euler did a LOT of math, so you'll probably see his name elsewhere. Fun Fact: He supposedly settled a bet between two of his students whose answer to a particular problem differed in the 50th decimal place... by solving it in his head!)\n\nNow, before we move on to natural logs, we need to talk about the (natural) exponential function e^x. If we were to graph the amount of money in our bank account over time, (with $1.00 initial deposit), it would follow the exponential curve *exactly*.\n\nAwesome, but suppose we want to know when we will have enough money to retire, say, $1,000,000? Well, we would just solve the equation e^t = 1,000,000 for t (t is time in years). How do we do this?\n\nEnter the natural logarithm. The natural logarithm is to the exponential function as dividing is to multiplying. In other words, the natural logarithm \"undoes\" the exponential function. This will allow us to solve for t.\n\ne^t = 1,000,000 == > t = ln(1,000,000) ~ 13.82 years\n\nUnfortunately, banks don't let you have it that easy. Interest rates (especially in this economy) don't even go near 10% let alone 100%, so the strategy here is to invest a larger initial amount and, of course, wait a little longer.\n\nHope this helps.\n\nEDIT: format",
"You say you are fine with exponents, let's use that as a basis for the answer then.\n\nMultiplication is to divison, as exponents are to logarithms.\n\nExample: 2 multiplied by 5 is 10. The same statement can be formulated as a division statement. If 10 is divided by 5, the answer is 2.\n\n2 to the power 5 is 32. So the logarithm of 32 (to the base 2) is 5.\n\nWait a minute, you say. What is this \"base\" business ? \n\nWell, just like with the division statement. \n\nYou can't ask - \"what is the quotient when you divide 10 ?\" \n\nI would respond - \"divide 10 by what divisor ?\" It's an incomplete question.\n\nYou say - \"oh, divide 10 by 5\". Answer: 2.\n\n\"What about divide 10 by 2\". Answer: 5\n\nSimilarly, in the case of an exponent, the base is the number that is being raised to a given power. So a logarithm has to be with respect to a given base.\n\nIt indicates to what exponent you would need to raise that base, to get the original number.\n\nSo, again to recap, the logarithm of 32 to the base 2, is 5. Because you would need to raise 2 to the power 5, to get the original 32.\n\nHomework: What is the logarithm of 100, to the base 10 ?\n\nEDIT: Wanted to point out a difference between the mult/div case, versus the exponent/log case.\n\nMultiplication is commutative, which is a fancy-pants way of saying that 5 times 2 is always the same as 2 times 5. Try it with other numbers.\n\nHowever, exponents are not commutative. 2 to the power 5 is 32, but 5 to the power 2 is 25. This is why unlike division, log of 32 to the base 2 = 5, but log of 32 to the base 5 is not equal to 2. It is 2.15338..\n",
"It's a very deep field, and there are a lot of things going on that are all related. It really takes a while to get a good understanding, so don't be discouraged.\n\nHere's some facts:\n\n* Logarithms are just the inverse of exponentiation. If you have a^b = c, then log c (base a) = b. The \"base\" is the base (bottom part) of the exponent. This is how I remember it: if you swap **b** & **c** (the parts closest to the equals sign) **a**, 'drops' into the base of the logarithm. (Write down this process a couple of times, and you might be able to visualize it yourself.)\n\n* Logarithms convert multiplication and division into addition and subtraction. Exponents do the opposite. This is how logarithms are used to make computations easier. Well, they become easier to do, not easier to understand. Here's how this works:\n\nlog(a*b) = log(a) + log(b)\n\nlog(a/b) = log(a) - log(b)\n\na^b * a^c = a^(b+c)\n\na^b / a^c = a^(b-c)\n\n* The natural log is the inverse of the exponential function. If e^x = y, then ln(y) = x.\n\n* But why is e important? There are a couple of deeply related reasons, but I'll start with the simple calculus explanation. You know how the derivative of a function can represent the 'slope' of a line? Well, we are saying that the slope of a line behaves a certain way at each point, and that we can describe that behavior with a function. That's what a derivative is. Anyway, if the slope is constant you get a straight line. If the slope doubles or triples every time you double or triple x, then you have a [power function](_URL_0_). But what if your slope function is just like the original function? Then you have an [exponential function](_URL_2_).\n\n[Aside] You can put whatever you want as the base for your exponential function: 2^x , 10^x , a^x. It doesn't matter because, thanks to the fact that logs and exponents convert between add/sub and mult/div, you can use a [change of base](_URL_3_) formula to get from one to another easily.\n\n* Back to e: Like I said, you can use whatever base you want. So why do we use e? Because, if you want your slope to be *exactly equal to your function* at all times, then e^x is the *only* function that does that! That's why it's called the \"natural base\" or the base of the \"natural logarithm.\" It's usually called *the* exponential function, because you only need one (as you can easily convert to all the others), and this one is the easiest to do calculus with.\n\n* Euler's number is pretty awesome for calculus. The exponential f(x) = e^x is the only function whose slope is itself: f'(x) = e^x . This means that it is it's own intergral, too: integral( e^x ) = e^x + C . There's also cool stuff to do with the natural log: d/dx ln(x) = 1/x, so integral( 1/x ) = ln(x) + C. Now, 1/x doesn't seem special at all, but you *need* to use e to integrate it!\n\nMore advanced stuff:\n\n* Remember how I said the exponential function was its own slope? Well, there is another kind of function that is its own slope: a [wave equation](_URL_1_). Look at a wave: it goes up and down. Look at its slope: it goes up and down. Maybe they don't go up and down at the same rate or the same time, but they do move together with regularity. You can use exponential functions to describe waves for this very reason, and a *ton* of math is about waves and cycles. In fact, you probably know what symmetry is. Well, a cycle is a kind of time-symmetry, and a wave is what happens when you combine space and time symmetries together. [This is why Euler's identities e^\\(i*pi\\) = -1 and e^(i*x) = cos(x) + i*sin(x) work.](_URL_4_)"
]
}
|
[] |
[] |
[
[],
[],
[
"http://en.wikipedia.org/wiki/Power_function",
"http://en.wikipedia.org/wiki/Wave_equation",
"http://en.wikipedia.org/wiki/Exponential_function",
"http://en.wikipedia.org/wiki/Change_of_base_formula_for_logs#Changing_the_base",
"http://en.wikipedia.org/wiki/Euler%27s_identity"
]
] |
|
41gr18
|
how does cleaning with water help remove dirt from surfaces
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/41gr18/eli5how_does_cleaning_with_water_help_remove_dirt/
|
{
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"A liquid is called a \"solvent\" when it dissolves another substance. So, for example, alcohol dissolves many oils, so alcohol is a solvent of oils. When you put alcohol onto something oily the oil dissolves into the alcohol and then you can wipe up the alcohol and oil mixture. That's how you clean something with alcohol.\n\nMANY liquids are solvents of different things, and it turns out that water is a solvent of tons of common materials. In the case of dirt, big particles get picked up just by the mechanical force of a liquid running over them. But anything binding or sticking the dirt particles to the surface will dissolve in the water, letting go of the dirt that can then be mechanically picked up and washed off.\n\nSome things don't dissolve in water easily or at all. Soap can be used to help things dissolve and get picked up, but sometimes that's not enough. For example, glue from a sticker can be really hard to wash off. It doesn't dissolve in the water at all. But it does dissolve in oil (oil is a solvent for those glues). You just need to put some oil (like olive oil or WD-40) on the glue and let it soak in for a few minutes, and then you can wipe the glue and oil right off and clean off the oily residue with soapy water.\n\nSo water is a solvent like any solvent, and so there are some things it can clean and some it can't."
]
}
|
[] |
[] |
[
[]
] |
||
1sv8ms
|
how a condensing boiler works.
|
Basic explanation of a condensing boiler, optimum temperatures, and if possible an explanation of included terms (saturation level, etc).
Thank you,
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1sv8ms/eli5_how_a_condensing_boiler_works/
|
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"I came here excited to learn what/how condescending boilers were/worked, and then I realized...",
"you know when you see steam coming out of the vent pipe for a gas boiler ?\n\nnormally with a boiler, you have a gas burner under a heat exchanger (some pipes with water pumped through)\n\nthe idea with a condensing boiler is, there's an extra heat exchanger before the flue pipe, so some of that steam condenses (turns back to water) on this heat exchanger, which heats it up\n\nthe water returning to your boiler (from the radiators/whatever) goes through this heat exchanger first, so it's as cool as possible\n\nfor the steam to condense, you really need that return temperature to be under 60'C",
"An ordinary boiler works like this: fuel is burned in a combustion chamber. Water runs through this combustion chamber in many small, winding pipes (a construction called a \"heat exchanger\"), which is how the water is heated. This works pretty well, and you can extract most of the heat gained from burning the fuel this way.\n\nHowever, some heat that's pretty hard to extract in a normal setup is heat that's *stored in the water in the exhaust*. When you burn fuel, the products of that reaction (assuming complete combustion - so no unburnt fuel) are mostly carbon dioxide and water (along with other products that depend mostly on the temperature of the combustion process and the exhaust, like carbon monoxide, nitrous oxide, and other, weirder products). \n\nNow that water, since it's very hot, is produced in gaseous form (as water vapor), not liquid water. That means that there's a significant amount of heat still trapped in that water vapor (water has a very high \"heat of vaporization\", which is the amount of energy required/released when it changes from a liquid to a gas). But it's essentially impossible, in an ordinary boiler, to extract that heat, because if the water condenses on the cold water pipes of the heat exchanger, it would usually just drop back down into the combustion chamber and evaporate again. \n\nWhat a condensing boiler does is that it manages to extract that heat from the water. It takes the exhaust gas from the ordinary boiler (which is still pretty hot, even after it is used to heat up the water) and runs that exhaust gas through a second heat exchanger, where it is used to heat up the cold water before it enters the main boiler. Since there's no direct source of heat in the second heat exchanger, the water vapor that's still in gas form when it leaves the main boiler can condense on the heat exchanger tubing into liquid water and release that stored heat into the water (where you want it to go!) instead of just having it go up the chimney with the rest of the exhaust like in a normal boiler. This means you've extracted more energy from burning the fuel than you could have in an ordinary boiler. As a bonus, it also uses the residual heat from the rest of the exhaust pretty well. Your exhaust coming out of the ordinary boiler might be as hot as 150 degrees C, but the second heat exchanger might allow the temperature to drop to only 40 degrees C. That's even more heat you've managed to get out of the fuel.\n\n(The extra heat you've extracted means you can get what's called the *higher heating value* out of the fuel, instead of the *lower heating value*. The difference between these two heat amounts can, depending on what fuel you're using, be as much as 10%!)\n\n(In a steam power plant, they use the same idea to improve efficiency, in a setup called an economizer)"
]
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[
[],
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|
ee8bcm
|
how do painkillers like ibuprofen work?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/ee8bcm/eli5_how_do_painkillers_like_ibuprofen_work/
|
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"There's two parts to this. Well, probably a lot more than two, but we're ELI5ish here.\n\nFirst, you eat the pill. It gets broken down in your stomach and intestine, just like regular food. Food has nutrients that get broken down into base chemicals, and absorbed into the bloodstream. Ibuprophen, and similar drugs, break down into base chemicals just like food. But these chemicals are special. Let's call our chemical Mac. Mac likes to bind to other enzymes in your bloodstream, including one we'll call Charlie. Charlie likes to hang out with a special enzyme named Frank. Frank and Charlie together are bad news, and cause inflammation. But if Charlie is hanging out with Mac, Frank can't join the fun. \n\nNow, side track, what is inflammation? It's when things swell up. That doesn't necessarily hurt on it's own, but if there is nowhere for the swelling to go, because say, you've got a bone or some skin there, we get pain.\n\nBack to the Charlie and Mac. Now that they are hanging out, and Frank can't join the party, we don't get inflammation. Without the inflammation, we don't have pain. \n\n & #x200B;\n\nThis is an incredibly high level and basic description, but the gist is, ibuprofen and other similar over-the-counter painkillers block the production of a chemical that ultimately leads to pain. Less of the chemcial, less of the pain.",
"There are 2 basic kinds of pain killers. Anti-inflammatories such as ibuprofen and analgesics such as morphine. They relieve pain in different ways.\n\nAnti-inflammatories, as the name suggests, reduces inflammation. They attack the pain at the source. You have a swollen knee, take ibuprofen, it reduces swelling, pain is relieved.\n\nAnalgesics work on the nervous system to reduce the feeling of pain. It basically comes in and tells your brain not to worry about the pain. The pain doesn’t actually go anywhere, but your brain doesn’t really care. It’s like going to sleep when you are hungry; you are still hungry but you are asleep so you don’t notice it. \n\nThere are also things such as nerve blocks which are much more localized. They block a specific nerve / set of nerves in a specific location. As such, you wouldn’t feel any pain past the block. Epidurals/ spinal blocks would fit in here.",
"Ibuprofen blocks the production or arachidonic acid, which is a potent signaling molecule for inflammation. Certain types of pain are associated with inflammation, particularly back pain. \n\nIbuprofen isn't like an opioid where it blocks pain signals, but by cutting the source of inflammation it cuts out the source of pain",
"Follow-up questions: \n\nShould you still take anti-inflammatories when you can handle the pain?\n\nDoes inflammation cause other problems? \n\nIf so, why does our body cause inflammation?",
"Ibuprofen is an anti inflammatory that works by reducing swelling and inflammation in tissues like muscle. It doesn't deaden your response to pain so much as it helps remove the cause of the pain. The pressure from swollen tissue triggers pain receptors and is the cause of much of the soreness and pain from soft tissue injuries like sprains, bruises, or even tooth aches. \n\nContrast that with an analgesic painkiller like acetaminophen which doesn't do much to stop the cause of the pain, but instead reduces the activation and signalling of pain through the nerves. IE it doesn't fix the problem, it masks the pain of it. \n\nWhich pain killer class works best, greatly depends on the source of the pain. \n\nI am not a doctor and this isn't medical advice.",
"A good point as a carpenter is changing pills helps. I dont like harder pills like vicodin etc because my friends have been addicted to them but switching from advil to aleve etc increases effectiveness a bit",
"I’m a hospital pharmacist and it’s really interesting how NSAIDs work. \nMost inhibit two enzymes called cyclooxyrgenase 1 and 2 (COX1 and COX2). One NSAID called Celebrex (celecoxib) only inhibits COX2 enzyme. Inhibition of COX2 has anti inflammatory effects but it’s also responsible for the prostaglandins which allow for the vasodilation of the affect blood vessels to the filters of the kidney. When you block the prostaglandins, blood supply is reduced to the kidney, filtration rate drops and blood pressure increases due to fluid accumulation and release of vasoconstriction chemicals that increase BP. That’s why NSAIDs carry a risk of cardiovascular disease. \nThe other NSAIDs also block COX 1. These enzymes help create the prostaglandins that create the bicarbonate (base) shield of the stomach (filled with acid). When you block the prostaglandins, you have no base shield in the stomach and your acid causes a hole called an ulcer. Since COX2 selective NSAIDs don’t touch COX1, they don’t cause ulcers...but cause heart attacks and strokes because they hit COX2 so hard.\nAspirin blocks COX1 primarily so it is very irritating to the stomach but doesn’t have as large of a cardiovascular risk. In fact, at low doses (75-100mg), it doesn’t significantly block prostaglandin synthesis but will still block thromboxane A2 (TA2) synthesis in platelets. This causes platelets to be less sticky and lowers your clotting risk (this lowers your risk of heart disease and stroke).\nBy blocking the COX1/2 enzyme system, they prevent the formation of inflammatory molecules that contribute to pain. However, as you can see, it comes at a cost.",
"You have nerves that send the feeling of pain from your body to your brain. \n\nThey can feel pain in different amounts, sometimes it's a small amount of pain sometimes it's a larger amount.\n\nA type of chemical is produced by your body that makes it easier to feel pain. \n\nIbuprofen blocks the production of one of those chemicals. The result is not being able to feel pain as easily."
]
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||
8va5en
|
why does a person feel more sleepy when day drinking and then stopping, than when compared to drinking from the evening onwards?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8va5en/eli5why_does_a_person_feel_more_sleepy_when_day/
|
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"Because alcohol is a depressant, if you drink and then stop you will feel tired and ready to sleep because thats what alcohol as a drug does to you. Generally if you drink in the night you will be going to sleep very soon after finishing drinking anyway which makes it kinda biased. However alcohol also converts to sugar basically which is energy so as long as you keep drinking you wont fall asleep as easily.",
"Because you stopped. The tired feeling is you sobering up/“coming down”. You’re gonna feel exhausted if you stop hours before you go to bed. Your body is in full filtration mode and working hard without the booze to stir things up. You’re also gonna be able to process just how exhausted you are as you sober up. I’ve been smashed several nights after a long day of work and had no problem staying up til 6am because I didn’t stop. ",
"Also understand the way alcohol effects different people. Many alcoholics get a stimulant response from alcohol so your perception on how it effects them and how that plays into when you see these individuals drinking skews things a bit. That and state of mind of the individual drinking. When you day drink I assume its without intent to be productive vs someone going out and not giving into the depressant bc they are on a mission to have fun.",
"Alcoholic vet here. From my own experiences even without alcohol i have a much easier time falling asleep mid day when i'm not doing anything. When i drink at night, I usually preoccupied with some activity. Clubbing. Concerts. Poker party. When im day drinking, i'm just sitting around playing a game or watching movies. Those stagnant behaviors for some reason, help put me to sleep. ",
"Agree with the responses that you become drowsy once you stop drinking, regardless of the hour. For me day drinking usually involves being outside in the sun, another contributing factor - makes you drowsy even without alcohol.",
"It’s very much down to your body clock, specifically your liver. Different organs don’t work at optimum level all day, and the liver function slows down during the lunchtime hours. This means it’s ability to filter out the crap is reduced. I don’t claim expertise in this matter, I watched a documentary on it. ",
"This is us right now. I want to know the answer nefore i take a nap cause im feeling a little drunk atm",
"Oh my God! This is me right now. After an afternoon of heavy drinking, I started feeling so sleepy, exhausted and tired, I had to say goodbye to my friends and come home early. Now, I'm just laying on my bed, browsing Reddit and I was thinking about the same thing just when I came across your post. What a co-incidence , right?\n\nThank you for asking. I used to think it's just a sign of not being a teenager anymore. But I have my answers now. ",
"Alcohol being a central nervous system depressant is sort of moot when you consider the complexity of that system. Yes, booze absolutely depresses certain parts of the cerebral map responsible for things like social anxiety etc. However, when acting on a complex system you need to take relativity into account. To depress one part of the brain is to lift another part.\n\nTo answer the question, you feel tired after drinking and then stopping because alcohol acts, in terms of subject experience, as a stimulant. I don't believe it's just for people who are alcoholics that this is true. And when you spend a chunk of time in a stimulated state your brain, always working to achieve a sort of homeostasis, fights that state... then the alcohol wears off and you feel exhausted. Your brain is still pushing against the parts alcohol was depressing and pulling against the parts being enhanced (relatively speaking). And so you yawn and yawn... but, you'll probably notice that if you don't nap and wait it out the exhaustion only lasts about as long as you were drinking; that's your brain again striving and achieving homeostasis.\n\nThis is why the morning after a heavy night of drinking you find all the negative feelings that were wiped out by alcohol are now actually enhanced. This is your brain overcorrecting. "
]
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||
1hqngl
|
why can't we make spaceships?
|
With the recent video of SPACEX making a shuttle that can fly back to earth without being lost, I was generally curious, why can't we bypass all of these problems and make spaceships? Now, I'm a huge scifi fan, watched star trek, firefly and stargate religiously, played (and still am playing the mass effect series), and in all fo these shows, films and games, spaceships are common and can leave and come back to the surface in matter of minutes.
Humanity has made planes possible, and for a time, even concordes, so why can't it make a "plane" that can fly out of the atmosphere, then come back and land ?
Now obviously I have zero knowledge of all of this, i'm just bathing in the hope that before I die I will be able to be on the bridge of a vaissel and fly in the solar system, but still, technically, why can't we "just make one" ?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1hqngl/eli5_why_cant_we_make_spaceships/
|
{
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"text": [
"It takes a somewhat rare element, Money",
"There's a lot of practical problems. For instance we can put a tube of people in space, we've already done so. But we don't have engines yet that can get them anywhere considering how enormous the distances are in space.\n\nThe enterprise has shields that can protect it even during combat. In reality a little bit of space debris can go straight through one of our craft.\n\nIn the end getting ready to go into space takes a lot of money. The people who have such money expect a return on their investment. They don't do it for visions of a space faring humanity."
]
}
|
[] |
[] |
[
[],
[]
] |
|
5jbl80
|
is it possible that something bigger than a blue whale lives deep in our waters?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5jbl80/eli5_is_it_possible_that_something_bigger_than_a/
|
{
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"text": [
"I suppose it's possible, but it seems quite unlikely. For one, it takes a lot of food to sustain such a large animal, and food is relatively scarce over most of the ocean depths compared to what's available closer to the surface. Secondly, things get washed up from the depths by tsunami and dragged up in nets all the time. We knew about giant squid long before anyone recorded a live one for that reason. So far there's no evidence of anything bigger than a blue whale."
]
}
|
[] |
[] |
[
[]
] |
||
1rkigi
|
coders/developers of reddit. how exactly does my video game console detect that the disc a copy?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1rkigi/codersdevelopers_of_reddit_how_exactly_does_my/
|
{
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"The pressed disk has data on it in special places that you can't write your own data to on a writeable disk.",
"A disk drive can tell the difference between a burnt disk (something you made at home) and a pressed disk (something made in the factory) because of the small differences in the disk. Because of the differences the disks have a header that tells a computer what type of disk it is so it knows how to read it correctly. \n\nBonus - So when modding modern consoles like the 360, you had to load custom firmware onto the dvd drive that told it to not freak out if it noticed the disk was a burned disk. ",
"The xbox and the ps3 both use headers/special disks that can be checked for authenticity. When loading a game from the disc, it checks to make sure that these sections (which cannot be burned to using commerical tools) are correct. It also checks region to make sure the disc is in the correct region (idk why they even do this anymore. Just let me play whatever the hell I want). \n\nThe gamecube was different because it used different discs (those small ass ones) and burned the data backwards I believe. The wii just burns the data backwards (spins the disc the opposite way as everything else), which means it is harder to create a replica of the disc. Also, you'd have to hack the firmware to bypass any checks/region locks still. \n\nThey all do region checks, so basically to get around the checks, you'd have to change the disc drive firmware. On the xbox360, some of them were easy because they stuck a samsung (or liteon, can't remember) in there with special firmware, and someone ended up finding the commercial driver for that disc drive and were able to put the firmware on there instead of the firmware that does auth checks. There were like 4 different drives that could have been in the xbox360, and I think only a couple of them had parallel drivers that could be put over the xbox 360. Also, they had to modify the operating system (you'd have to format your drive with a special modified xbox 360 operating system on your hard drive that would bypass checking that the firmware was a valid firmware).\n\nThe playstation 3 didn't really allow you to update the disc drive firmware I don't think until someone found a way to flash the NAND chips on some of the playstation 3s (not all of them could though). I think there was an OS hack in there as well, but I don't know much about modding the playstation 3, although I have been working on #rpcs3, so I know quite a bit about the internals, just not the operating system/hard ware exploits. \n\nThere's also some chips you can buy that you solder onto the motherboards. What these chips do is intercept these authenticity checks and then send back the correct data. Really not worth it and they're detectable (I think at the hardware level consoles can tell/do stuff to discover them) so its really a shot in the dark with those. I've never used hardware mods, but rather just software mods. ",
"Many methods of copy protection have been invented and cracked over the years. An example: PlayStation 1 (remember the black discs?) have a special CD Drive that can read data from a track on the disc that is not accessible using standard CD drives. The drive seeks to this special spot (near the center of the disc) and reads a special code from this track to verify game is legit. Hackers quickly found ways to get around this. The most prolific solution was to modify the PS1 to intercept the signal and respond with the appropriate code. This logic was built into a small integrated circuit and sold online as device allowing users to verify \"backup\" discs. If one has the 'mod chip' installed in the PS1, he/she can simply copy an original black disc using a typical CD burner then play it on the modified PS1. You know, so you didn't damage your original game disc by playing it. And stuff...",
"one way is this...This is how they did it back in the diskette days but is probably still interesting/relevant.\n\nWhen you ask your operating system to make a copy of a disk, you are essentially saying \"please take data from here and put it there in whatever way you please\"\n\nWhen copying, operating systems don't generally *write to a specific track or sector* on the disk. Often the native copy command, can't for instance write to track 1, sector 1 specifically. \n\nSo when the creator makes the disk he puts a code right in that spot. If that code is not there when the software starts up (the s/w checks with a low level command, \"is there an X on track 1, sector 1) it knows it's a copy. \n\n\n",
"It's a trap :p",
"also the dvd drivers usually let you know the type of disk via api calls (that come from firmware responses). The laser can detect what type of material makes up the disk)",
"Ok, I will explain how copy protection works on PS1 and PS2, since that's what I am well versed on, but I can't say definitively how it works on other consoles.\n\nSo to start, you have to understand that the tracks on CD/DVDs are not a perfect spiral. There is a \"wobble\", which is that the track itself moves back and forth in a sine wave perpendicular to the direction of the track. This \"wobble\" is 15 kilohertz and some change, IIRC. The tracks exist independently of the data, which is to say, when you buy a blank disc, the track, with its wobble, is already there. A Playstation game changes the wobble slightly on the lead-in (the part of the track closest to the center where that the drive uses to orient itself prior to reading any data). So when the head is orienting itself on the lead-in, it follows the wobble of the track. By measuring voltage and impedance of the motor that runs the head, the system is able to determine exactly how fast the head is moving back and forth, and determine that it is different from a normal 15khz. If the wobble is exactly correct, a analog-to-digital converter circuit then sends the okay (this depends on the region, for America the chip sends hex the representation of \"SCEA\") to the CPU and allows the game to be played.\n\nThis is why it is still impossible to play burned games on a PS1 without modifying the console in some fashion.",
"Read up on PS1 modchips. I'm not sure how modern systems do it."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
||
bsm7ny
|
why are so many things squared (power of 2) in physics? what is it about square values that makes them integral to a lot of things?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/bsm7ny/eli5_why_are_so_many_things_squared_power_of_2_in/
|
{
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"eoodkkm",
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"score": [
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"text": [
"Several things spring to mind. I'm ordering these in terms of increasing math level: the last two only make sense if you've taken calculus, which most five-year-olds haven't.\n\n1) Areas are measured in length squared. Quantities that involve area coverage, or \"stuff\" spreading out over a certain amount of space, tend to involve squares or inverse squares. (Examples: gravity, electricity, fluid flow)\n\n2) The square of a quantity is symmetric about zero: a negative quantity squared is positive. So if a phenomenon depends on how *much* something changes, but not which *direction* it changes in, a square will often appear. (Examples: energy)\n\n3) We often successively approximate complicated functions using simpler ones via Taylor series: we assume the function is constant, plus a linear slope, plus a squared term ... and often that's accurate enough and we don't need to go to cubes and higher. And because of point #2, the linear slope will often be zero. (Examples: pendulums, wave speeds)\n\n4) Second derivatives seem to hold a special place in the universe -- Newton's Law, Maxwell's Equations, the Schroedinger equation, all involve a second derivative. If some basic quantity (like, say, acceleration) is constant, then it's the second derivative of a squared quantity.\n\nMy points 2, 4, and maybe 1 are probably related through [Noether's Theorem](_URL_0_), but that's waaaaay beyond ELI5.",
"It turns out that a lot of the things in physics can be represented by a graph and you get all sorts of useful numbers out of figuring out the area under the graph. Take the relationship between acceleration, velocity, and time. Let's say you're free falling on the earth and there is no air resistance. Earth is constantly pulling down on you at 9.8 m/s^2. The formula here is f(t) = 9.8 where t is time. If you graph this as a function of time you are falling, it would be a horizontal line at 9.8. At 1 or 10 seconds, the earth is sill pulling on you at 9.8 m/s^2. \n\nWhat if you want to know how fast you are falling at 10 seconds? How fast you are falling is actually the area of the rectangle formed by the graph surrounded by t=0 and t=10. This is 9.8m/s^2 * 10s = 98 m/s. You may recognize the formula: v=a*t + c (c is the initial speed which is 0). a*t is just the area of the rectangle made by the graph. In our case it is v=9.8*t. If you graph this you will get a diagonal line.\n\nWhat does the area of the space under the v=9.8*t graph represent? It represents how far you have fallen after t seconds. The graph is a diagonal line which forms a triangle. The area of a right triangle is a*b/2. The integral of this graph is represented by (9.8*t)*t/2=4.9*t^2. \n\n > What is it about square values that makes them integral to a lot of things?\n\nSo hah, you made a pun. It's integral to a lot of things in physics because physics uses a lot of integrals. You find interesting things when you do so. Integrals do not always result in a square term, but it often times will and you will see it more often than terms to higher powers like 3. \n\nSo you may be asking what happens if you keep going? You can find the integral to that which would result in a formula with a t^3 term in it. As for what this number means, as far as I know it's not a particularly useful number as the unit is m*s. Acceleration is m/s^2, velocity is m/s, position is in meters.",
"It happens when something is multiplied in intensity with itself. For example, if you increase the side of a square while keeping it a square, the other side will increase. Now you get the extra area from one side plus the extra area of another.\n\nImagine light traveling out equally in all directions from a candle. The actual photons being emitted don’t magically increase, however the further you get from the source of the light the more area the same amount of photons have to cover, so their density decreases according to the distance they are from the source. (Light at 2 feet will be 1/4 the density of light at 1 foot since it’s twice as far away. Multiply that “2x as far” by itself and you get “4x less dense”.\n\n_URL_0_\n\nThere’s another way to look at the inverse square law. Imagine the plastic squares are the surface of the imaginary sphere the light is covering at a given moment in time. As the light moves away equally from the source, it spreads out both side to side and up and down, yet since the same amount of photons exist they just get rarer. The area they’re covering increases as a square.\n\nOther time, it pops up as the square root of a number squared. Sometimes formulas do this so that they don’t have negative values measured. It doesn’t have to do anything innate in that objects relationship to being multiplied by itself though.\n\nFor example, in securities pricing models you may want to measure how often a stock deviates from the market average. You need to add up the total deviation and divide it by the measurements to get its average deviation, but if you count every time it falls below that value as a negative value and every time it rises above as a positive, it may have extreme variation but average out to little variation since the positives and negatives cancel each other. To remedy it you’ll square all numbers and then take their root, which makes a negative positive since a negative times itself will be positive. -2*-2=4, 2*2=4. The square root of four is 2.\n\nOther times, if a formula is not sensitive to the raw values but how those values stack up against others, they won’t even bother taking the root.\n\nTL;DR: 95% of the time it shows up when something increases or decreases in intensity with itself. 4% of the time it shows up in relation to taking measurements of things that need to be a positive value. 1% of the time it has other applications.\n\nThey’re also closely tied to calculus, but it’s for the same exact reasons stated above."
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Noether%27s_theorem"
],
[],
[
"https://imgur.com/gallery/nntICMb"
]
] |
||
1rshro
|
how do people on shows like "bering sea gold" not freeze to death under water?
|
Baffles me how they can be under for like 6 hours and seem unphased.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1rshro/how_do_people_on_shows_like_bering_sea_gold_not/
|
{
"a_id": [
"cdqelux"
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2
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"text": [
"They use drysuits that allow the user to stay dry while they are underwater and they wear layers of clothing underneath to stay warm. For extreme duration low temp situations they also pump warm water from the ship, down a tube and into the suit."
]
}
|
[] |
[] |
[
[]
] |
|
36tchk
|
why is it that even when a video on netflix or youtube has buffered, it can still be jumpy, laggy, or straight up potato quality?
|
Surely the buffering is the video 'downloaded' and it just needs to be 'played'?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/36tchk/eli5_why_is_it_that_even_when_a_video_on_netflix/
|
{
"a_id": [
"crgwgvt",
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],
"score": [
3,
2
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"text": [
"**HEY... YOU!!! DONT YOU MAKE FUN OF OUR POTATOES.**\n\n**-Sincerely, 9GAG community**\n\nSometimes your video card might screw the file up, your hard drive may need a defragmentation because it takes too long to find the files, or the site might send you corrupt files from time to time. ",
"The cause is a buffer is usually a set size. Like 8MB, if your connection is too slow, even after buffering you can drain the buffer before it fills back up. A lot of streaming algorithms will try to reduce video quality to one that can be streamed in real-time or close to it, which is the cause of the potato quality. There is a minimum quality that services like netflix will stream at, if your connection is too slow to refill the buffer at this low rate than you get potato + stutter."
]
}
|
[] |
[] |
[
[],
[]
] |
|
2yns8c
|
why don't hostages in execution videos put up more of a fight or struggle when they know they are going to be killed anyway?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2yns8c/eli5why_dont_hostages_in_execution_videos_put_up/
|
{
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"cpb934h",
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"text": [
"they're absolutely gauranteed to be caught if they try to run or fight so now rather than getting killed they get tortured horrifically then killed - that would be incentive enough to just sit there crying\n\nsecondly, a lot of them probably have a thought in the back of their mind that it won't happen. Maybe it's a practice run, maybe they'll leave me alone. I know if I was in that situation I'd be thinking till the last moment \"this simply cannot be about to happen to me, not to me.\"\n\nmaybe religion has something to do with it - a lot of the victims are the devoutly religious nutters that probably have an incredibly fatalistic view on life, have been covered in death and destruction since they came out the womb and genuinely believe they're about to go and get 72 virgins or be with their dead family or whatever. Some of them probably aren't too bothered to die.\n\nAnd some, of course, will want to run with every fiber in their body but simply can't, they're frozen with terror.",
"Because they actually don't know they are going to be killed.\n\nMost of the time these hostages are dragged out in front of cameras and made to read stuff or stand as a prop many, many, many times over the course of their imprisonment.\n\nNot only are they regularly beaten and threatened but they are also told that they will eventually be released as long as they do what they are told.\n\nSo imagine you know you will be hurt if you disobey, you have been told you will be freed eventually if you behave - a ransom is met or whatever - and you have been sat in front of a camera to read a pre-written farewell note 20 times already over the last few months. . . it gets to the point that's it's business as usual for you as a captive.\n\nYou have no idea that this particular day is the day everything goes as it always has, except this time instead of them cutting the filming and walking you back to the truck, they cut your throat. ",
"Allegedly they are lulled into a false sense of security by doing it repeatedly (without being killed), while being told it's for video to get the hostage's government to pay money.\n\n\nAfter a few times of being dragged in front of the camera just to go through the same rigmarole and then put back in their cell or wherever they're kept, they just sit there and let the kidnappers go through with it cos it's just another video recording."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
a8n95t
|
what doe the ghz in a pc mean and do? what's the benifit of having more?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/a8n95t/eli5_what_doe_the_ghz_in_a_pc_mean_and_do_whats/
|
{
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"ecc286r",
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4
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"text": [
"It stands for “gigahertz” and it’s got to do with he CPU’s clock speed. Basically meaning how many cycles a cpu can run in a second. ",
"1 GHz means \"1 billion times per second\" and for a CPU this controls to some degree how fast it can do stuff, it runs 1 billion times per second so it can go 1 billion things (cycles) per second.\n\nWith modern CPUs there are a lot of things that affect speed on top of this, so it may not be as clear cut. For example one CPU might attempt to start 2 instructions per cycle, while another starts 4, one might have 1 core while another has 8, each which attempt to start a certain amount of instructions per cycle. And on one CPU an instruction might take 5 cycles to complete but another it takes 10.\n\nThus, GHz is good for measuring the relative speed of two CPUs that are the same internally, but comparing an old i3 to a new i7, it's not really useful."
]
}
|
[] |
[] |
[
[],
[]
] |
||
dklkot
|
what is random process?
|
For instance, what does it mean in the following sentence dedicated to sampling:”In other words, the more people that are included in a sample, the greater chance that the sample will accurately represent the population, provided that a random process is used to construct the sample”
Thanks in advance.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/dklkot/eli5what_is_random_process/
|
{
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"f4h4c6j"
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"text": [
"So let’s say you want to know what the most popular car in the US is by survey. If you surveyed the entire city of New York you’ll have a huge sample, but does that one city really represent the whole US acutely? No. You’d need to get surveys from cities and towns all across the country so they can be more random. \n\nAs your sample gets more randomly selected the likelihood your sample represents the whole population increases. If you don’t randomly select your sample it can skew or bias your results."
]
}
|
[] |
[] |
[
[]
] |
|
3y5i8r
|
how come our stomachs don't explode when we eat mentos and drink coke, but when the two are mixed externally, it causes uncontrollable fizzing?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3y5i8r/eli5_how_come_our_stomachs_dont_explode_when_we/
|
{
"a_id": [
"cyapfhn",
"cyapt21"
],
"score": [
4,
2
],
"text": [
"the fizzing is gas being released by a chemical reaction. when that happens in your stomach, the force is not great enough to make you explode, but will result in hefty burps and farts. try it",
"You have two release valves in the stomach and it can expand to an incredibly size before rupturing. You instinct to vomit triggers long before the risk of rupture is reach unless you have ulcers or something in your stomach that can pierce it. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
4gv6lb
|
how can the ocean become low on oxygen when water is one part oxygen?
|
I read that scientists are worried the ocean will lose its ability to obtain oxygen from the atmosphere in as little as 10 years. How is this possible when water is one part oxygen?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4gv6lb/eli5how_can_the_ocean_become_low_on_oxygen_when/
|
{
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"text": [
"Free oxygen isn't the same as oxygen bound into another molecule. Fish can't strip oxygen from hydrogen, that would take a huge amount of energy and some very interesting biology.",
"Because they aren't talking about oxygen bound up with other elements. They're talking about gaseous oxygen (O2) that is dissolved in the water that is essential for aquatic life.",
"That oxygen isn't available for use, because it is bound up in the water. The oxygen in question is dissolved oxygen saturating the water. Not the oxygen the water is actually partially made of.",
"When people talk about oxygen in water, they're not talking about the oxygen in actual water molecules; they're talking about oxygen gas (O2) that's dissolved in the water. That's what fish and the like need to breathe.\n\nThe oxygen atoms in water molecules aren't readily available for the same kind of use.",
"The oxygen that is part of a water molecule is not usable for respiration.\n\nUndersea lifeforms get their oxygen from gas dissolved in the water.",
"Imagine a single girl who visits a medium-sized city, looking to date. She goes to bars and nightclubs but finds few eligible bachelors to date or hang out with. She exclaims: \"Why aren't there enough MEN in this stupid town?! I see them all over the place but I cannot find any to date!\"\n\nThe bartender points out that there are in fact 100,000 men in town, but 99% are already married to someone. So even though the city is full of men, there are almost no men *available* for the girl to hang out with.\n\nMarried men = the oxygen atoms inside water molecules.\n\nTheir wives = the hydrogen atoms inside water molecules.\n\nThe bachelors = free oxygen atoms not already attached to other, non-oxygen, atoms. \n\nThe girl = animals and plants that need free oxygen to survive"
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[]
] |
|
5mq9hv
|
why does greenland have more ice than iceland and vice-versa? [other]
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5mq9hv/elif_why_does_greenland_have_more_ice_than/
|
{
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"text": [
"Iceland was discovered first, and they could hardly call it Evenicierland. \n \nThe main theory is that Eric the Red decided to call it Greenland to lure people there, knowing that noone would show up if he was going to be honest about what it was like.",
"Oh i know why Greenland is called Greenland! Erik the Red was exiled there from Iceland. He wanted to develop the Island more with communities and people and such. But it was a rather barren icy place, so he called it Greenland in order to attract more people there. ",
"Greenland is huge compared to Iceland, it's also extends further North. More land mass allows more space for ice. That's why Greenland has more ice than Iceland.\n",
"Literally, because Greenland is a gigantic glacier reaching into the arctic north. Iceland is an island on the arctic circle but is both not as far north and is geothermal powered and sits in the middle of the gulf stream. \n\nAs for the names:\n\nGreenland was named by Eiríkur Rauði (Eric the Red) when he went there in exile for manslaughter in Iceland. he employed a bit of deceptive marketing by naming it greenland, either because where he was it was green or because he wanted more buddies to join his colony.\n\nIceland has gone under several names, but the name \"Iceland\" is generally credited to a man called Hrafna-Flóki (Raven-Flóki), named so as he had three ravens he used to navigate to Iceland. He didn't quite like the island, most of his livestock died due to weather, and during the closing of his trip he climbed a mountain in Vatnsfjörður and saw there into another fjord which was filled with snow and icebergs in the water. After that he and his men starter referring to Iceland as Iceland. "
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
3e25zm
|
why was the 90s rap scene so violent? it would be ludicrous to imagine marilyn manson shooting trent reznor despite violent lyrical themes. why was rap so different?
|
Music is a multimillion dollar business full of lawyers and men in suits. It's a giant corporate machine. I find it really hard to reconcile this big smooth business having musicians shooting each other in the streets. Why was the scene so violent and full of so many deaths?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3e25zm/eli5_why_was_the_90s_rap_scene_so_violent_it/
|
{
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"The thing is, artists like MM and NIN sing about violent themes but it's mostly fantasy. It's an image they're trying to portray, it's not the reality of their lives. The 90s rap scene was the exact opposite. Those guys didn't have to imagine what it was like to live in impoverished communities where gang violence and crime was rife, they lived it. An upbringing like that is sometimes hard to shake, no matter how long you've been out of it. ",
"Rappers' battles were ingrained in their culture, it was real. They lived and breathed their craft. NIN and Marilyn Manson were pure fantasy.",
"A lot of those guys were actual members of criminal gangs, and had already been violently assaulting people long before they were celebrities in the public eye. \n\nCheck out all the rappers in the [wikpedia category page for Crips](_URL_0_).\n\n"
]
}
|
[] |
[] |
[
[],
[],
[
"https://en.wikipedia.org/wiki/Category:Crips"
]
] |
|
6k5tic
|
when humans aren't to blame, how do animals go extinct?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6k5tic/eli5_when_humans_arent_to_blame_how_do_animals_go/
|
{
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"text": [
"Just off the top of my head:\n\n* Natural disasters destroying their habitat\n* Natural shifts in climate destroying their habitat\n* Food shortages\n* Diseases killing either them, or a necessary link in their food chain\n* Being out-competed by a rival species",
"Dinosaurs would be the primary example: natural disaster.\n\nEvolution would be other: lots of animals went extinct because they evolved out of existence to something more practical\n\nBut nowadays, it's mostly humans fault because we are jerks.",
"This is a great question, and it lets us really sink our teeth into some basic biologic concepts. First of all, though, there are two basic types of extinctions: Mass extinctions, and isolated extinctions. Mass extinctions refer to vast numbers of species going extinct over relatively short period of time (usually meaning over a few millennia). These are rare events - five mass extinctions have occurred in the history of the world (some consider us to currently be in a mass extinction event - the \"Holocene extinction\" - which is largely human-caused.) These events are caused by natural disasters, such as the most recent asteroid collision at the Yucatan peninsula, which is believed to have driven the dinosaurs extinct. Earlier in earth's history, large volcanic eruptions were responsible for blocking out the sunlight, affecting plant life, and temporarily changing the climate enough to drive species extinct on a mass level.\n\nIsolated extinction is much more common, and is happening all the time. Some of this is simply the result of evolution. As a species evolves, the older version of the species can be said to be \"extinct\". The definition of a species is somewhat arbitrary. There's not always a perfect division between two species. For example, wolves and dogs are genetically similar to the point that they can interbreed. However, they are considered different species due to other factors - wolves tend to have a very characteristic appearances, and a well-established behavior such as pack formation with a complex hierarchy, hunting techniques, howling as an important means of communication, etc; dogs have a lot more variation in their appearance, and are characterized by domestication, interaction with humans, loyalty to their adoptive families, barking more than howling, etc. Dog and wolves don't naturally interact and under most circumstances would regard each other with hostility, and so they are considered other species. Wolves in general tend to be more \"pure bred\". But, if wolves bred more and more with dogs, over time, the offspring would stop being wolves, and start being more mutt-like. If this happened enough, the wolves would disappear, not because they were killed off, but because the things that defined them as a species disappeared. This process is called Genetic Pollution. \n\nDisease is another major cause of extinction. A nasty virus that affects a plant could wipe out and entire colony of plants, for example. This could lead to downstream effects, as the animals that feed on that plant might then die off. \n\nFinally, animals can hunt each other to extinction as well, particularly invasive species that arrive in a new ecosystem and eat faster than they are eaten. \n\nEDIT - crappy grammar",
"TLDR: Animals adapt, through evolution (tiny mutations) to their environment to be able to survive in it most efficiently. When the environment changes suddenly (new predator, temperature, lack of food) and the animals can't adapt fast enough, they get really bad at surviving in that environment and all die.",
"Out here in central valley CA, the California condor should be extinct. They're massive scavenger birds that eat the remains of Tule elk, but for the last few thousand years (within this glacial period), the Tule elk's population and range have naturally diminished with lowering temperatures (less edible plant growth). \n\nBut now in this political/environmental climate, normal people want preservation over utilization (everyone in the field wants \"sustainable utilization\") so therefore that's where the funding/donations go. So now, we pay people to dump dead cows out in the mountains in specialized feeding troughs for the condors we're raising and releasing into the wild. The problem is that they have no ability to live on their own and we'll have to keep supplying them with dead cows if we want them around. \n\nAlthough with rising temperatures in the last hundred years or so, we're seeing record growths of forests (keep in mind atmospheric CO2 is plant food and rising temperatures generally mean more rainfall), so it's possible we might see the return of megaflora and then megafauna, although not in our lifetime for sure. ",
"They just fail to adapt to changing conditions or get out competed by other species.\n\n99% of all animals went extinct without human intervention."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[]
] |
||
bv2q7w
|
why do arcade video games and flight simulators use mirrors to reflect the monitors instead of just letting you look at the monitor?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/bv2q7w/eli5_why_do_arcade_video_games_and_flight/
|
{
"a_id": [
"epkhtlb",
"epo0vq8"
],
"score": [
15,
2
],
"text": [
"Talking about the old school arcade cabinets?\n\nCRT monitors are big, and deep. If they put the CRT upright at eye level the cabinet would be twice as deep. Laying it down facing up at a mirror is much more compact.",
"If you're watching a monitor, you're focusing about 30 cm. When you're flying, objects are usually pretty far. So, professional simulators use mirror system to put the display as far from your eyes as possible, in order to simulate what are you seeing in a real aeroplane.\n\nSee: _URL_0_\n\nThere are two exceptions, which should be shown near: runway side mark bars (I don't know its proper name) and on-the-fly tanker tube."
]
}
|
[] |
[] |
[
[],
[
"https://en.wikipedia.org/wiki/Full_flight_simulator#Collimated_Cross-Cockpit_Displays"
]
] |
||
6m6tqm
|
waking up without depression
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6m6tqm/eli5_waking_up_without_depression/
|
{
"a_id": [
"djzbve5"
],
"score": [
2
],
"text": [
"Sleep and depression are closely linked.\n\nPoor sleep can actually cause depression. _URL_1_\n\n_URL_0_\n\nThe mechanisms are not well understood. Most surprisingly, sleep deprivation also helps!\n\n_URL_2_"
]
}
|
[] |
[] |
[
[
"http://www.shape.com/blogs/shape-your-life/sleep-therapy-may-help-cure-depression-faster",
"https://www.psychologytoday.com/blog/the-power-rest/201311/want-treat-depression-get-people-sleep",
"https://www.scientificamerican.com/article/why-sleep-deprivation-eases-depression/"
]
] |
||
5v1rm5
|
why is spacex so interested in vertical landings? with all the knowledge we have about mars and its terrain, wouldn't it be easier to plan a "horizontal" entry to the planet, similar to how astronauts land on earth?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5v1rm5/eli5why_is_spacex_so_interested_in_vertical/
|
{
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"score": [
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"text": [
"I don't think the whole landing trajectory is vertical, just the last part of it so they have a reusable rocket.",
"Landing rockets is about the reusability and therefore reduced cost of rocket launch in the first place.",
"Taking off from a horizontal landing is harder then a vertical landing. By landing vertically its technically possible to land on mars establish a colony and take off again in the future.",
"The space shuttle lands at like 220mph... lol it requires literally a couple miles of flat runway. No such thing exists on Mars. And mars is capable of very high winds and an unforgiving rocky surface. ",
"The issue is landing so you can reuse the rocket. The cheapest way to do that is vertically. You just can't deaccelerate quickly enough horizontally. \n\nThink of the old NASA shuttle. It ditched the booster immediately after launch so it didn't have so much mass to deal with and slow down on reentry. The goal of spaceX is to keep that booster.",
"If you're talking about landing like a plane, it would be very hard to land like that on Mars. Why? Because of the extremely thin atmosphere that wouldn't generate sufficient lift at all. It would also be hard to find stable ground until a proper runway would be built. It is much easier to just land vertically and take off vertically.",
"SpaceX's stated goals are highly reusable, relatively cheap rockets. They want to be able to re-use every part of the rocket that isn't fuel. In order to do this, they need to make sure that they can land the rocket somewhere they want, i.e. opening a few parachutes and floating down is not an option. Landing like a plane requires wings and wheels (not to mention the complexity of designing a plane and a rocket), that increases costs and number of parts that need to be inspected and maintained. Landing vertically then is the next best option. Is it insanely difficult? Yes. Think landing an explodable radio tower into an area a little bigger than it's base. Is it also the only option that adequately meets their goals? Yes, as far as engineers have figured out."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[]
] |
|
eeyz9s
|
japanese people and the tradition of having kfc for christmas.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/eeyz9s/eli5_japanese_people_and_the_tradition_of_having/
|
{
"a_id": [
"fbxbu0n",
"fbxbxa2"
],
"score": [
4,
2
],
"text": [
"When KFC first came to Japan it came around Christmas time and was sold to the people as America's favorite Christmas pastime. Trying to be trendy that's what they did. In turn it became a Japanese tradition lol.",
"A lot of Japanese people have an irresistible attraction for everything European or American. They often try to emulate what they believe are the customs of these countries, and the powerhouse that is Japanese marketing is more than happy to oblige. However, having lived both in small and large japanese cities for 11 years, I have noticed that it is changing. Most of my friends, and people I know love to cook an upgraded dinner sometimes around Christmas eve (since 12/25 is a work day) and have a small party. Also, many restaurants offer dinners based on turkey and/or French style food."
]
}
|
[] |
[] |
[
[],
[]
] |
||
28v9fk
|
why does the inside of my lower jaw feel weird after i piss (after a while of holding it in)?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/28v9fk/eli5_why_does_the_inside_of_my_lower_jaw_feel/
|
{
"a_id": [
"ciesr80",
"cifde3f"
],
"score": [
2,
2
],
"text": [
"If you hold your pee for too long, maybe your teeth were floating?",
"I KNOW WHAT YOUR TALKING ABOUT!\nAnd I don't know why. But tensing the muscles upwards gives me a stronger feeling."
]
}
|
[] |
[] |
[
[],
[]
] |
||
2g0rxg
|
bruising a bone
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2g0rxg/eli5_bruising_a_bone/
|
{
"a_id": [
"ckekd82"
],
"score": [
4
],
"text": [
"A bone bruise refers to any type of injury that causes bleeding inside of a bone. Bones have a huge network of small blood vessels that run through and around them, so if any of these blood vessels break, it will cause bleeding inside of the bone. "
]
}
|
[] |
[] |
[
[]
] |
||
18xm6e
|
why companies like google and microsoft do not release their own brand of cell phone?
|
I've always been curious. Google created the Android platform, and Microsoft has Windows 8, but as far as I know neither company have created any actual hardware for these platforms. Would it not be smarter for them to create some hardware for their software, and make a device that functions exactly how they want it to rather than having to rely on 3rd party locked apps?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/18xm6e/eli5_why_companies_like_google_and_microsoft_do/
|
{
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"c8iyhci",
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"score": [
2,
9,
3,
2,
6,
2
],
"text": [
"Its only a matter of time.",
"In google's case, google works with hardware manufactures to produce the nexus series of phones, which are used to design android and are in effect the official android phone.\n\nMicrosoft produces the Surface tablet line, which includes both a windows RT and an 8 tablet, and other things like the xbox.\n\nThere is actually one good reason why people who make operating systems shouldn't maintain a single device that is the only device guaranteed to function as intended, the reason being that it fails to underscore the need for a good operating system to work on a wide range of hardware, which locks down the market and decreases consumer freedom.\n\nFor example, because apple maintains the Macintosh line of computers that are the only computers they consider when making OsX, if I want a computer that runs OsX I have very few choices, and apple is free to artificially drive the price up on that range of hardware (which, at least in my opinion, they do plenty of). Now I could set up a hackintosh, but that could get messy and complicated and I loose official support.\n\nNow if I want to go out and buy a computer that runs windows, I have no such limitation, there is a huge market full of hardware of all prices, and not only can I buy one that more closely meets my exact needs than is possible with a Mac, the prices are kept down by competition. In this case I can slap windows on almost anything and not fear that it will get messy or not have support.\n\n**TL;DR: They do, Google has the nexus series of phones and tablets and Microsoft has the surface series of tablets (Microsoft currently does something near to the thing google does with their nexus line for phones).**\n\nEdit: To expand on the microsoft thing, microsoft used to throw around nokia phones as being the \"real\" windows phones, but they have sense switched to considering the HTC Signature series as the base of all windows phones.",
"You do realize google recently bought a cell phone company? They do in fact make phones. ",
"Besides the fact that they do? Well, the reason they aren't exclusive or like the iPhone or that its a larger part of the business model is this: its cheaper and less risky to license software. No inventory, no overhead...just profit. And they can commit to the hardware at any time they chose to. Like google has done recently.",
"Google has, at least, the Nexus line. They aren't actually manufactured by Google, just designed by them, but then, neither are iPhones manufactured by Apple - they are manufactured by Foxconn under license and design by Apple.",
"Apple doesn't make all of their iPhones either. A lot of the components in an iPhone is actually manufactured by other companies including Samsung. \n\nApple design the hardware, but they don't make it themselves. They get all the parts from available manufacturers, send them to the Foxconn assembling plant where it is assembled before being distributed.\n\nThat's why it says inside the box \"Designed by Apple in California. Manufactured in China\""
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[]
] |
|
62jtrz
|
can we just spit out candy, junk food, etc. like gum after we chew it to cancel out negative nutritional effects?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/62jtrz/eli5_can_we_just_spit_out_candy_junk_food_etc/
|
{
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"dfn4d82",
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],
"score": [
6,
3
],
"text": [
"Your saliva is already starting to break down whatever it is you're chewing on so your body is already consuming the good and bad before it hits your stomach. At least, that's my understanding of what's going on. Like people who use chewing tobacco don't swallow in order to feel the effects of the nicotine. ",
"Technically possible but extremely difficult to pull off.\n\n\nOn the savory side, say you're eating peanuts, or popcorn, or chips. By chewing and enjoying the taste, you've already squeezed out and swallowed whatever oils they were cooked in. You've also likely swallowed at least *some* of whatever you're chewing without realizing it. \n\n\nWithout sweets like sugary candy and chocolates, think of them as slowly dissolving in your mouth; you would have unknowingly swallowed sugary syrup or liquid chocolate before you spat out the mass. \n\n\nLet's also not forget most of the pleasure we derive from eating these foods derives from more than *just* the taste alone. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
9de6by
|
how can gas prices fluctuate daily if a gas station buys large amounts of gasoline by the truck-full? are stations constantly at risk of taking a loss on already-purchased gas?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9de6by/eli5_how_can_gas_prices_fluctuate_daily_if_a_gas/
|
{
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"text": [
"Gas stations don't determine prices. Their supplier sets the price of the gas they sell based on current market rates. If the gas station bought 1000 gallons last week at $3.50/gallon and still have 500 gallons left the following week and gas prices jump to $4/gallon they won't continue to sell at $3.50/gallon ",
"Gas stations get a \"Dispensing Fee\" for the gas pumped. The rest of the money goes to the petroleum company who set the price. While the price of gas fluctuates the Dispensing Fee is fairly constant.",
"I managed a gas station that was part of a super-center. Twice daily we had to drive around and record our competitors prices. If a station just down the road was even $0.01/gal cheaper, our sales went through the floor. So we adjusted our prices. \n\nIf everyone else raised their price, and we hadn't we would be slammed. Sometimes we couldn't afford to send someone out to check prices making the problem worse. So once we became aware of everyone else's price, we raised ours.\n\nWe were not a oil company owned station (not sure if there are such things?). Our supplier (tanker truck) drove to the nearest refinery, filled up and was charged by the oil company. \n\nThen they delivered the fuel to our station. We were billed what the oil company charged plus the delivery fees.\n\nNow we owned thousands of gallons of fuel at that cost. But as I said above, we could only sell it for what people were willing to buy it for.\n\nSometimes we were lucky and bought low, sold high. Other times we bought high, sold low.\nOur corporate goal was to break even on fuel. All of our profits came from inside \"convenience store\" sales.\n",
"All I can add to this is:\n\n & #x200B;\n\nWhen I was a pumping ping in Indiana in the late 80's; the store manager would \"go shopping\" 3 or 4 times a week to check gas prices in the area. She would then modify our price when she returned. This had no bearing on when the tanker supplied us."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
1pvbc2
|
if i ground up a piece of pure iron and ate it, would my body abosorb it the same way as iron from food? if not, how do they make iron supplements absorb-able?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1pvbc2/eli5_if_i_ground_up_a_piece_of_pure_iron_and_ate/
|
{
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"cd6f5zk",
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"cd6gn2l"
],
"score": [
11,
29,
3
],
"text": [
"If you ground it up enough, your body would be able to absorb it. However, the recommended daily intake of iron is only 18mg, so you would need a very small piece of iron or you would run the risk of iron overdose.\n\nHowever, iron supplments are usually provided as part of a compound, such as iron (II) fumarate, iron sulphite, or iron gylcinate, which are absorbed more readily by the body.",
"You eat shaved iron every time you have breakfast cereal. If you take total cereal, crush it up, add a little milk to make a broth consistancy, and stir it with a strong magnet, you will see actual iron shavings sticking to your magnet.\n\n_URL_0_",
"A fun fact along side other peoples post: One of the benefits to cooking with a cast-iron skillet is that it increases the iron level in the food because little bits of the iron stick into the food itself. "
]
}
|
[] |
[] |
[
[],
[
"http://www.youtube.com/watch?v=ZIyKe9VE6o8"
],
[]
] |
||
3qoil7
|
how the hell do the companies making all those free (and generally shitty) apps afford prime time television commercial slots?
|
Actually, Tribal Wars 2 was pretty cool for a few days, but that Battleship one got boring as fuck quick.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3qoil7/eli5_how_the_hell_do_the_companies_making_all/
|
{
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"cwgz4uv",
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4,
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2
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"text": [
"Two main ways: \n\n* Volume of users: if 1 million people spend $5, that is still $5 million brought in for a cheaply made game\n* Backing companies: if for example King (Candy Crush makers) wanted to try to make another game big, they might dump a boatload of cash into it, hoping it would take off. ",
"Freemium games. They are free to download, and essentially are built to frustrate the user, unless they are willing to pay money. Candy crush is an example, you get X amount of attempts every 24 hours to finish a level. If you fail, you either way, or pay 2 bucks and get to go again.\n\nNow spread that to 10 million people, because fuck it, its free. Not all of them will pay the 2 bucks, but those who do, might also pay more than once, and fairly regularly. Now you have a shit ton of money.",
"Besides the Freemium business model, there is also the \"if you're not the customer, you are the product\" business model.\n\nOn the internet in particular, anything you think you get for free is because the data they get about you is worth more than anything you would be willing to pay for the game/app.\n\nInfo about you, your location, your preferences, ANYTHING they can pull from your devices - selling that is big business.",
"They're free to download and play but they pretty much have a paid element (\"freemium\"). Research has shown that for games that use this model, the majority of revenue is derived from a relatively small number of players. So say you have a million people dowload you game. 800,000 of them might never spend a penny on it. 150,000 maybe spend $5, and 40,000 might spend $10. Bu the remaining 10,000 could spend a relative fortune (say $200) which supports the 'freeness' for the majority. that's why the best (by which i mean most successful) freemium games use game mechanics that are deliberately enticing to this crowd. There's a question about whether it speaks to the obsessive nature of some players and how moral that is, but the short answer is that 'free' games can still make a huge profit, and that's why they can afford to pay for TV slots. ",
"In Germany you will see **many** different mobile **games** advertised, but in the end it's all from **one** **publisher**. My guess is that it's the same in the US. 20+ games advertised, ONE firm behind (and paying ad costs for) them all.",
"Micropaying! Southpark did a good episode on this\n\nAllow me to explain the science behind micropay premium gaming. For years gaming was simple. You pay for the game and you enjoy. With mobile apps we now have the ability to make games that are boring and stupid. But if you pay for incentives, you're rewarded!\n\nIt's a simple cycle. A never-ending loop based on RPG. Explore - > Collect - > Spend - > Improve. But whereas those just use the concept of XP or Experience Points, we've introduced the idea of micro-paying with money. Money. Money. Money money money money."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[]
] |
|
c5a2gu
|
why does iv contrast fluid cause a warming sensation?
|
Had a CT Scan today and was wondering why the IV Contrast causes that warming sensation. Also, as a side question, why does it cause that brief sensation of nausea?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/c5a2gu/eli5_why_does_iv_contrast_fluid_cause_a_warming/
|
{
"a_id": [
"es0inh7"
],
"score": [
5
],
"text": [
"Iodine, which is in IV contrast, makes your blood vessels relax and expand. This relaxation allows your blood vessels to hold a larger volume of blood - think of a pipe expanding. This increase in blood volume increases the total heat available per unit length of the blood vessel and in turn warms the tissue. Peripheral sensing dude, nerves, pick up on this temperature change and tell your brain that your body parts are getting warmer."
]
}
|
[] |
[] |
[
[]
] |
|
2mw3m3
|
ronald regan and his significance in politics today
|
It seems like he's held up as the gold standard for Presidents or always the rebuttal Democrats use against Republican criticism of liberal policies. The only thing I really know about him is "Reganomics" and that it didn't work.
Why does everyone seem to love him so much?
What did he do and why is it still so relevant?
Edit:
My question was actually inspired by this post on r/politicalhumor
_URL_0_
(On my phone sorry for link format)
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2mw3m3/eli5_ronald_regan_and_his_significance_in/
|
{
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3
],
"text": [
"He was charming, and was President when the Cold War ended, and was President during an economic boom. He gets credited for the good things and the bad things are ignored.\n\nPlus, he was the last Republican President to be popular with Republicans and Democrats alike, so he's a good role model to point to. If the GOP says \"Our next guy will be nearly as good as George W Bush!\" then 70% of the country will not be impressed. \"Our next guy will be nearly as good as Reagan\" is more persuasive.",
"Because it's easy to point to the past. We remember the past fondly, and don't remember all the bad stuff. Ronald Reagan, in today's political climate would be considered a moderate democrat or a VERY liberal republican. He was pro gun-control, he was pro-progressive taxing (meaning the wealthy get taxed more than the poor), and he tripled the national debt (certainly not fiscally conservative).",
"The Democrats had great iconic 20th Century presidents in JFK and FDR they could use to inspire people to vote for them. The GOP had to go all the way back to Teddy Roosevelt, who was getting past his expiration date.\n\nWithout there own iconic great, it was necessary to invent one, and the legend of Reagan was born. He showed charisma and leadership after two weak and one disgraced president, presided over the end of a recession and then a modest recovery, and was lucky enough to win the \"when will the Soviets implode\" office pool. Beyond that, it was a scandal ridden presidency with few clear accomplishments.",
"Because he had the Balls to commit high treason (Iran-Contra scandal) to win the presede goal election against the Democrats. You don't see that kind of determination from today's Republicans.",
"Republicans love him because they are Republicans. His fans liked his swagger, confidence and 'Murica attitude. Rich people liked his economic policies, he greatly lowered the taxes on rich people and got the deregulation snowball rolling. Jimmie Carter (a man I admire greatly as a person but not as a president) was pretty much seen as ineffective and the US was seen to be without direction. Regan had the appearance of knowing exactly what needed to be done and inspired confidence. Older Republicans admire him with some sort of god-like zeal (though there is a HUGE amount of cherry picked facts about him going on here), everyone else either doesn't get it or seriously dislikes him.\n\nWe are still suffering from his economic policies. Regan expertly sold the idea that lowering taxes actually lowers the federal deficit by raising economic growth so much that it more than makes up for the loss. It has never worked but, since it helps rich people, the idea just won't seem to die.\n\nTL/DR: Myth supported by selective memory.\n"
]
}
|
[] |
[
"http://editorialcartoonists.com/cartoons/PlantB/2014/PlantB20141119_low.jpg"
] |
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[],
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[]
] |
|
1bj0sq
|
why do venues keep ticket prices relatively low, allowing ticket resellers to make such large profits?
|
Oftentimes resellers are able to mark up prices 100%-500%+ from the face value of tickets. Why don't venues significantly increase the face value of their tickets and take a lot of the profit being made by resellers?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1bj0sq/eli5_why_do_venues_keep_ticket_prices_relatively/
|
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"Because the venues themselves don't want to become reviled as the party doing the \"ripping off\". In reality though, many venues are also responsible for a lot of the reselling, though this is certainly more true of some establishments than others. ",
"First, the resellers can only make that profit if the event sells out. Do they sometimes pull nonsense to force the sellout? Yes. But if they mess up, they lose money. \n\nSecond, they provide a service. Much like the people who stand in line for new video game systems and then sell them to the highest bidder, the resellers provide a service at a price. Do they cheat? More and more, yes. But someone working from nine to five has less time and more money than a college student, but both are desired patrons.\n\nNow, why don't venues try and \"price the tickets correctly\" in the first place?\n\nFirst, it's really hard to do. Venues aren't going to hire an economist full time to hunt down all the band's old sales records, cross reference them with the city's demographics, account for other events across town, and carry the employment level to find the perfect equilibrium price that *just* sells out the venue. Even if they *did* scalpers would still be able to make money on half the tickets, because half the market would be willing to pay more than the median price, you know?\nThe only real way to avoid (other than differing pricing levels) this would be with some kind of auction system, where everyone can bid on tickets and get it closer to the proper market level for everyone. But that kind of system is expensive, has it's own flaws, and basically just isn't worth it for the venue itself to do, but perhaps worth it for a third party to exploit (especially one like ticketmaster that can tackle the entire country instead of just a single venue.)\n\n\nSecond is simple fairness. Bands don't want teenagers to be left out. They don't. There's a reason why Fugazi kept their shows at $5 a ticket for as long as they possibly could. Most musicians started into music when they are young, have a connection to music that is young, and have a target audience in mind that is young. So they want to know that young people can make their shows. Double the price of already expensive tickets, and you've got a huge problem.\n\nThird, some artists have huge egos. \"Why was Metallica $XXX dollars? Why aren't I? You saying Metallica is better? I'm never coming here again\" and so forth. Unfortunate, but true. (Ideally huge swings would be handled by different venue levels, but such is things.)\n\ntl;dr: It's near impossible to get the prices right, and the profits the resellers make are made from the service they (theoretically) provide to ticket buyers as well as the risks they take."
]
}
|
[] |
[] |
[
[],
[]
] |
|
9vvh1h
|
how does domain and range work?
|
i have been using a new software called grasshopper 3d and it asks for domain and ranger for quantities and i get confused.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9vvh1h/eli5how_does_domain_and_range_work/
|
{
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"text": [
"Domain is the set (you can think of this as a list, I guess) of all possible inputs to a functions; range is the set of all possible outputs.",
"Domain=possible x values (of your function)\n\nRange=possible y values (of your function)\n\nSo for a function like x^2 the domain is from -infinity to +infinity, and the range is 0 to +infinity."
]
}
|
[] |
[] |
[
[],
[]
] |
|
1u2jj3
|
why won't a plastic cup with water in it melt?
|
I once placed a solo cup full of water in a fire, and the cup didn't melt. I could never understand why.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1u2jj3/eli5_why_wont_a_plastic_cup_with_water_in_it_melt/
|
{
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"The energy goes into the Latent energy of phase change.\n\nThe heat energy goes into breaking the phase bonds of liquid to make the water into a gas. This means the cup isn't getting enough energy to raise the plastic's temp in order to melt. Water is very good at stealing energy and takes over 4000J to raise a single degrees (Celsius). ",
"Because water evaporates before it has a chance of getting hot enough to melt the plastic. The water's boiling point is lower than the plastic's melting point.\n\nThere are some types of plastic, like polycaprolactone, that are engineered to have a low melting point, in that even warm water can melt it, so you could actually have a plastic cup that would melt if you poured hot water in it."
]
}
|
[] |
[] |
[
[],
[]
] |
|
3ooh6t
|
why is it so common for people to be afraid of something that hasn't hurt them yet like snakes/heights, but not of things that they've probably been hurt by before, like knives and stoves?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3ooh6t/eli5_why_is_it_so_common_for_people_to_be_afraid/
|
{
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"Our fear response is aggravated by unfamiliarity. And conversely familiarity brings comfort.",
"I have read that there's evidence that both the examples you gave are instinctual fears. Put a glass surface on top of a smaller table, and babies will hesitate to crawl beyond the surface of the table onto the stable glass. Infants and toddlers also show an aversion to snakes when exposed to them for the very first time. The hypothesis is that infants who developed these fears by chance were more likely to survive long enough to grow up and reproduce, so the fears ended up dominating the species over time.\n\nFact-check me. Believe nothing you read from a random stranger on the internet.",
"Evolution. It is advantageous to have a fear of things that could poison/kill you like snakes/heights. Knives and stoves are quite likely to just inflict a relatively superficial wound and not stop people from reproducing."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
3yw3qz
|
how can dust particles exist in space? wouldn't they be attracted by the gravity of the nearest object with a greater mass?
|
Wouldn't all the dust particles clump together and form larger and larger objects? What am I missing here?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3yw3qz/eli5_how_can_dust_particles_exist_in_space/
|
{
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"cyh5duq"
],
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"text": [
"Gravity is, for reasons we don't know, a ridiculously weak force. Dust particles tend to be positively charged. So, if they haven't already been sucked up into a star, planet, comet, or other more massive thing, they like to float free. It isn't until there are enough dust particles clumped together that gravity finally overcomes their naturally repulsive forces, and that dust cloud gets sucked into being something else -- like an asteroid, comet, or whatever.\n\nIn stellar systems where most of the dust and gas has already been sucked into what it's going to become, it's very easy for the leftovers to remain floating free because they're already in points which the overall forces of gravity haven't reached, and aren't likely to for a long time.\n\nMeanwhile, in nebulae and the like, that dust is going to eventually get sucked into being a star or a planet, but it's going to take millions or billions of years to do so."
]
}
|
[] |
[] |
[
[]
] |
|
6ka26z
|
why some races are more genetically predisposed or prone to some sicknesses or disorders
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6ka26z/eli5_why_some_races_are_more_genetically/
|
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"Usually because its a trade-off for defense against other diseases. For example if you have sickle cell anaemia you are defended against West Nile syndrome. Its all about the environment you are in.",
"It's a misnomer to define it as related to race. Most commonly it is a genetic mutation that affects one group who happens to be of a certain race, or it is socioeconomic where a certain race is over-represented.\n\nWith regard to the genetic mutation, often the genetic mutation results in benefits where natural selection allows the mutation to proliferate even though it may affect longevity. One example is sickle cell anemia, which is an illness commonly found in certain regions of Africa. Research shows that the genetic mutation also results in a lower infection rate of malaria and impact of malaria. Hence it was a trait that served them well, despite the increased risk of the sickle cell anemia. And the mutation is most commonly found in regions with malaria.\n\nAnother example is a mutation in Northern Europe that makes people more prone to being infected with the flu. It is believed that the mutation results in more frequent exposure, and thereby helps strengthen the immunity system which makes them less exposed to deadly versions of the flu.\n\nEqually often though the mutation is purely random. If the effect is only to reduce longevity (like many cancers) and not impact the likelihood of them surviving until adulthood and having children then natural selection will not weed it out.\n\nThe socioeconomic aspect I assume is self-explanatory.",
"Think of it like breeds of dogs, sort of. They are all the same animal but because of isolation of certain populations and interbreeding they develop issues that other breeds don't have. Pugs with breathing issues, dobermans with small skulls for their brain, dalmatians and whatever the fuck is wrong with them, etc \n\nWhile on dogs this is something forced on them by humans as they look for certain looks and traits that cause complication, but even short term separation can result in populations that that have varying degrees of susceptibility based on local pressures \n\n"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
6653ce
|
what is the silicon valley?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6653ce/eli5_what_is_the_silicon_valley/
|
{
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"Silicon Valley, a big ass area near San Francisco with loads of tech companies like Google, Apple, Tesla just to name a few.\nThe name comes from the green boards in electric devices, its made of silicon.\nIf you want to make an IT start up, this would be your dream, but the competition is immense."
]
}
|
[] |
[] |
[
[]
] |
||
9b5z7t
|
why are we fascinated by things that glow?
|
I was reading about the radium girls and stumbled on some articles that said people used to consume radium back in those days, which got me thinking about all the autoluminescent (I hope it's the right term) objects that brings out the child in us. I bet most of us would be drawn out of curiosity to get a closer look at, say, a firefly or the stars but is it something that we're hardwired to do?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9b5z7t/eli5_why_are_we_fascinated_by_things_that_glow/
|
{
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"Mostly because light comes from things we expect them to come from. Fire, the Sun.\n\n & #x200B;\n\nBut to have it come from something unnatural, and not emitted by a flame or filament is almost unearthly. Not many things on earth luminesce under natural light or darkness."
]
}
|
[] |
[] |
[
[]
] |
|
5cfpwo
|
why cant we use our phones wifi instead of bluetooth
|
Why can't we in newer cars use our wifi to stream music instead of the more in my opinion finicky Bluetooth?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5cfpwo/eli5_why_cant_we_use_our_phones_wifi_instead_of/
|
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"WiFi uses a lot more power, and that's a problem for 2 reasons. It costs in battery life (over 30x the power required for WiFi), but it also causes interference issues in this case.\n\nSay you're stuck in traffic and there are 10 cars around you also playing music over Bluetooth, fine - there's 40-80 Bluetooth channels available depending whether you're using the Low Energy standard. Generally Bluetooth works best over the first few feet, but is limited to about 30ft, so the interference between devices will be low.\n\nWiFi, however, is powerful enough to broadcast to the 10 cars in front and behind you, and everyone in the lanes next to all those cars (up to 300ft). There's also only 11 WiFi channels available (in the United States; a maximum of 14 channels in other countries).\n\nSo you can see how having a low-power device is best for this application. I can say from personal experience, the newer Bluetooth devices operate a *lot* better than the older ones for streaming music. My old deck was basically unusable for music over Bluetooth, but I've never had an issue on my new one (using the same phone). You might look into what version your deck and your phone are operating on, and see about an upgrade if that feature is important to you."
]
}
|
[] |
[] |
[
[]
] |
|
4ypna7
|
why is heating something on a low heat for a long time not the same as heating something at a higher heat for a shorter amount of time
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4ypna7/eli5why_is_heating_something_on_a_low_heat_for_a/
|
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"There are a lot of answers to this question. \n\nIn some cases it is the same. Take a rock and heat it up really fast or slow, the effect is largely the same.\n\nThe problem comes with things like baking, which I assume we are talking about here. As we know, baking involves yeast. It also involves proteins and fats and all sorts of biological molecules. Baking them at a really high temperature kills the yeast, denatures the proteins, and potentially burns the fat.\n\nThe essential crux of it all is that some molecules are more stable, others not so much. There's a reason life can't exist in hot environments and that's because the molecules literally fall apart. Water, on the other hand, is extremely stable, for example.\n\nThere's also the issue of how long something takes to heat *through.* Imagine a steak. You sear it on the outside and it's still pink inside. We've all accidentally baked frozen chicken, too. This happens because it takes time for heat to transfer, also a major reason for slower heating.",
"At higher heat you allow some other reactions to occur which have the effect you don't want. For example, if you heat up bread enough you can set it on fire. This is not the same as the reactions for cooking it as you are combusting the carbohydrates rather than denaturing the yeast.",
"Imagine a piece of steak. Properly cut, it's about 3cm thick, or more. \n\nNow imagine putting this in a really hot pan (maybe more than 200ºC). The surface that touches the pan will heat up quickly, and the side that's far away will heat up only very very slowly. The center of the steak will warm up as a result of conduction (heat being transferred from one molecule to the next within the steak), but meat is a bad conductor of heat. So most of the heat will be stuck near the outside and not be transferred to the inside. The longer you leave the steak on, the more likely the outside will dry out and burn. Eventually the inside will increase in temperature, which will cook the center, but at a high heat, the pan side will be ruined.\n\nContrast this with a slow cooker: a device that uses a moderate or low temperature, and allows everything to reach one temperature over a long time. So, if you leave a steak in a slow cooker for a long time, everything will end up being the same temperature (maybe 80ºC), and nothing will be burnt, and nothing will be \"rare\".\n",
"It's because power matters.\n\nBy power, I simply mean the amount of work (aka, transfer of energy) done within a certain amount of time.\n\nThink of it this way: which one of these could more people do? Do 20 reps with a 10-pound dumbbell, or 2 reps with a 100-pound dumbbell?\n\nIn the end, you are still doing the same amount of work.\n\nThe same goes for cooking. There is a certain threshold in energy transfer (ex. heat in cooking) that must be met or avoided for certain things to happen. Some phenomena are just all or nothing like that.",
"Thermal transfer mostly. It takes time for heat to move through something, so putting a lot of heat into one spot makes that one spot heat up way faster than other spots, and it also gets much hotter until it can dump heat into its surroundings (other parts of the thing you're heating) as fast as you're putting the heat in. This becomes a problem if whatever you're heating can't go above a certain temperature (like baking). It's the same reason the bottom of a pizza cooks faster than the top. Lots of heat coming from the bottom, so it gets hotter and cooks before the top has time to absorb that heat.",
"I'll add a non-cooking reason for your consideration.\n\nWhen welding thin walled steel tubing for aircraft applications, you could weld it with an arc of electricity (3000 to 20,000 C), weld it with a gas torch 3400 C, or weld the ends of two tubes together using friction. \n\nSteel melts at 1500 C, give or take a few. Arc welding is fast and works for just about any geometry of parts you want to join. Gas welding is slower, but allows you to work on thinner materials without blowing big holes in them. Friction welding is just hot enough to melt the ends of the two tubes so that they join, but joining tubes is its only use.\n\nWhen you weld steel, as soon as you stop welding and look with your naked eye you can see the heat \"run away\" from the place you welded. The steel is changing colors as the high heat disperses through the steel, running from yellow and red nearest the weld to violet and blue furthest away from the weld, to no color change where the wave of heat ran out of calories. \n\nThe problem is this: rapidly heated steel, especially from arc welding, becomes embrittled. This means it will crack and break under real usage, like landing your plane. This is never a good idea ;-) \n\nTherefore, the standard practice is to use a gas torch for thin walled tubing to limit the heat to only what's necessary, and slowly back off the torch so that the metal cools a little slower. The is often followed by heating with a warm, large flame to further reduce any brittleness and ensure the metal parts will do their job in the real world.\n\nIt is the rapid heating and cooling that puts stress into the metal. Metal's crystal structure changes as it heats. Rapid cooling will freeze the metal at a particular crystal structure, some of which are very hard but brittle, and some of which are hard enough but tough and strong. In my mind, I see this freezing happening before the sides of the crystals can align with each other, so energy doesn't flow smoothly through the metal. This causes stress risers, little bottlenecks in the flow of energy, which are the ultimate cause of brittleness. Reheating and cooling more slowly allows the crystal alignment to take place (chill out, little crystals!), smoothing out the energy flow during real use.\n\nBack to food.\n\nThis is similar to what happens to that steak you ordered at that place with the wood fired grill. They will have a hot zone and a not so hot zone on the grill. They will sear the the outside of the steak on the hot part, because caramelization increases the flavor. We like that. Then, they will move it to the not so hot section to finish cooking the inside of the steak. Keeps things moist and tender; we like that, too.\n\nWith fish, the chef will pan sear the fish to get that tasty crust then finish it under a broiler to preserve the crust but cook the filet through in a more gentle heat.\n\nNeato heato!",
"Imagine a bucket with holes in its bottom. The bucket represents the properties of the material: its width is the heat capacity, the volume of liquid is the quantity of heat inside the material and the level of liquid is the temperature. The holes represent the dispersion of the heat. The point is when you start pouring water in this bucket, it starts being filled up but some water drains through the holes. If the flow is so low that all the water escapes through the holes - you have no temperature rise. But lets start to increase the flow. It is possible to find such flow values that the level of water inside the bucket rises - and so rise the temperature. If the level is high enough the water level will fill the bucket completely and start to pour from the top. This case can corresponds to melting/boiling/burning etc. This analog is not complete if we talk about real, \"thick\" materials. In this case you can imagine that water which escapes from the bucket's holes goes to the next bucket. If you turn on the high heat the first bucket will be overflowing and the next will be barely filled. This happens when you try to cook up a stake on high heat. And of course, these buckets can be of all sizes: the wide ones correspond to materials which are not so easily heated; the tall ones represents the ones which are capable to be heated to high tempertures without damage.",
"Because temperature is related to the average activity level of jiggling molecules, kinetic energy, and there are a lot of activity thresholds in chemistry and physics. For example water boils at 100° C; you can't make it boil by heating it for a longer time at 80° C. The reason for this is a certain threshold of jiggling is required to pull water molecules apart from one another against their tendency to stick together.",
"a lot of the answers here are needlessly complicated or specific, so let me try to give it a shot: \n\nYou can put the same amount of energy into a thing by heating it slowly (=with a lower temperature difference) for a longer time, or faster for a shorter time. That energy is the same. But what's different is:\n\n1. Heat distribution.\nThink of a steak here. You can cook it really fast and really hot. That will not give the heat enough time to dissipate to the core, so it will stay uncooked. If you do it slower and longer, you'll end up with a thoroughly cooked piece of meat.\n\n2. Specific things only happen at certain temperatures.\nThis is why you got so many field specific answers. There are lots of effects temperature has that don't have anything to do directly with the amount of energy put into whatever you're heating. Some are:\n\n- material becoming softer and expaning (steelworking)\n\n- lifeforms dying\n\n- phase changes (water evaporating, specific crystal structures like austenite forming)\n\n- chemical reactions\n\nI hope that was a somewhat useful overview. As a sidenote, your terminology isn't like in physics. You call an amount of energy heat, to differentiate it from temperature. They don't directly translate because different materials need different amounts of energy per mass to reach a certain temperature.",
"Low heat for long time usually means Low temperature (let's say 130F)\nHigh heat for short time usually means High temperature (let's say 700F)\n\nTemperature is one of those things that \"tries\" to equal out, so everything becomes the same temperature.\nSo when you apply low heat/low temperature, it will never get hotter than that temperature.\n\nSO, what's the difference? Let's say we are heating up a rock.\n\n1. Some reactions only occur at a high enough temperature. So maybe the rock won't melt(lava) unless it reaches that high temperature.\n\n2. Given a long enough time, the rock will be that temperature on the inside and outside. If you don't give it enough time, only the outside will get to that temperature.",
"When I first attempted to make a panini, I cooked it on high. When the outside looked done I took it off. \n\nAfter taking a bite, I realized that the cheese didn't melt all the way and the meat was still cold. \n\nSo I tried again. This time on medium. \n\nIt cooked far more evenly and the cheese melted, holding the sandwich together.\n\nCooking on lower temperatures provide much more evenly cooked foods which allows heat transfer. \n\nIf you ever want to cook steak. Use High for rare, and Low for Well. Medium for Medium. ",
"/u/ADogAndOnFire Because of this : _URL_0_\n\n\"Pretending you're five\" : some reactions will never start if you don't give them enough \"triggering energy\".\nLow heat : some reactions occur.\nHigh heat : more reactions occur, including the ones from the \"low heat\" group, plus others. \n\nSimplest example : boiling water. \nPro tip : you can change that \"energy threshold\" for a reaction to occur, for example by changing other factors. For \"boiling water\" : lower the pressure (water boils \"faster\" at high altitude). \n",
"I see a lot of long comments, I'm gonna just tl:dr it for those who want it. \n\nlow heat over long time allows the entirety of the object to heat to whatever temperature that's desired (Heated all the way through, not a lot a variation in temperature of different areas of the object)\n\nHigh heat over short time heats the outer parts but usually leaves the center relatively cool (large variation in temperature of different areas)",
"True ELI5 (because I can't find one) unrelated to cooking:\n\nImagine you are outside on a really hot day. You start to feel very warm on the outside, then with time you feel hot inside and outside. This is low heat for a long time. The time allows heat to spread evenly. \n\nNow imagine you place your hand on a stove burner. The very outside of your skin will get very hot and will get burnt, but inside you will feel exactly the same temperature. This is high heat for a short time. There is no time for the heat to spread. \n\nDepending on the situation, sometimes you want to hear just the outside of something, and other times you want to hear the entire thing, inside and out. ",
"Don't know if I'll be able to help, but Gourmet coffee roaster here. I just started the cool down sequence of our roaster (pictured below), so maybe I can take pictures of the process tomorrow.\nMy English is bad. \n\nHere is a [picture](_URL_1_) of coffee beans going through the\n[Maillard reaction](_URL_0_) .\n\nFor coffee roasting, the proper application of heat is crucial. Similar to baking and searing stakes, roasting coffee is highly dependent on how heat is applied over time.\n\nIf heat is applied too quickly, the energy does not go throughout the bean , and the Maillard reaction as a result does not occur evenl,y does not occur at all, or the desired compounds are not formed or transformed. In coffee this results in uneven color, loss of pleasant aromatics, and loss in flavor to name a few. \n\nFor example, let's say we have a coffee that we want to highlight its acidity, but a complex and approachable acidity like that of a red delicious rather than vinegar.\n\nLet's imagine we are roasting coffee. To start the Maillard reaction, let's say our beans internal temperate needs to be at 280F. We need to apply heat over time slowly in order to raise the temperature and ensure that the bean is endothermic throughout, and that the beans hit the desired temperature of 280F at the same time and not unevenly based on how close they are to the roasters rotating drum wall. \n\nLet's say acidity with our equipment starts to peak in the Maillard reaction around 350F. If we are to add heat too quickly, the Maillard reaction accelerates and the compounds that bring the character of acidity that just peaked can be fully burnt up, resulting in the loss of that flavor and aroma. When released from the roaster it will have been a dull coffee. If we are to gradually manipulate heat and observe the acidity slowly taper off however, we can observe the difference in acidity level by aroma and release the coffee when a desired amount of the compounds translate to acidity are at a desired level, which in turn translates to a balanced acidity over a harsh vinegary one.\n",
"probably due to internal convection; over a long period you have enough time for the outer thermal \"pulse\" to reach the centre (think: roasting meat til the centre is cooked)",
"Heat is basically just movement at a really tiny scale. Think of when you tap your abs for five minutes. This is low heat (small motion) for a long time. Compare this to a hard punch to the gut. This is high heat (large motion) in a very short time. In the first, those small taps have their force spread and dissipate quickly and don't add up to as much of a change to your abs. In the second, the force hits so fast and so strongly that there'should no time for it to all dissipate before it has an effect.",
"The way I like to think about it is with a grilled cheese....\n\nIf you are making a grilled cheese and throw that bitch on high, the bread will be prime... however the cheese won't be melted since the bread wasn't hot long enough for the heat to get to the cheese. \n\nIf you cook it slowly that heat will radiate through the bread longer, and progressively melt the cheese while toasting the bread. That's some tasty fucking shit right there.\n\nI'm pretty sure this same sort of concept applies with most food. Assuming you are talking about food.",
"Chemist here. Think of a hole/well you dug in the ground and call it the ground state. Above ground, the land next to the hole, is the excited state. \n\nIf I was to fill in the well with ice-cold water slowly, it would gradually fill to the top uniformly at almost constant temperature. If I was to dump a pale of water very fast into the hole, chances are water will splash out onto the outer excited layer and there would be huge temperature deviations in \"pockets\". ",
"**Short Answer**: Higher temperatures create localised areas of higher heat closer to the heat source, which may be high enough to result in inadvertent chemical reactions. On average both types of heating are the same but the former is more uniform.\n\n**Long Answer**: Say you're cooking something that has biological stuff like yeast that will cook perfect at 80 degrees and dies past that. You're in a hurry so you put the oven to 150 degrees and plan to take it out really quick. It should only go up to 80 degrees if you get the timing right so the yeast will be okay right? When you pull it out what happens? The side closest to the heat is burnt and dead whilst the other is undercooked. \n\nWhen you suck water up a straw it doesn't all end up in your mouth immediately right? It has to travel up. Heat is the same. In the above, you gave one side a lot of heat to travel to the other side. Yes, for the entire object you cooked, the average temperature is 80°, but near the heat it might be at 140° whilst its only 30° on the other side. Like how water levels out to a still and flat surface, the heat will even out until the whole thing is of the same temperature, but by that time the side that was hot has burnt to shit. Next time you decide to leave the heat at 80° and everything heats up slowly but nicely, because nothing will go past 80° because you aren't giving any energy above that temperature.\n\nSo why did it matter in the first place? Why can't you let one side be 140° and have it level out till everything is perfect at 80°? Well, because chemical reactions have an activation energy. This is pretty much (to make it simple) the temperature at which chemicals react in a certain way. Our yeast has an activation energy that is met around 82°. Before that, the yeast won't die. It's the same requirement that makes sure things don't combust until they meet a certain temperature.",
"Because of something called Specific heat, What is Specific Heat you say? Well Specific Heat is the amount of energy required to increase the temperature of something by one degree. Imagine pulling your Jacket zipper up and down really fast but for a short period of time now touch tour zipper you'll notice you can only get a few spots really warm but the rest of the zipper is room temerature. Now imagine pulling your zipper up and down for about 1 minute and stop and feel your zipper you'll notice the zipper is warm across the whole zipper and thats because over time the zipper was able to disapatw the heat across each tooth of the zipper allowing for even distribution of heat.",
"If you are talking about the cooking, their are two reasons why they don't result in the same thing.\n\n1) It takes time for heat to enter a piece of food. If your temperature on your oven is too high then the piece of food will start burning before the center of your food is done. Burnt on the outside and raw in the middle is not a tastely combination. If you keep your oven low and take a long time, the heat has time to enter the center of the food before it can damage the outside. This is also why you rotate food when you cook.\n\n2) There certain chemical effects that happen that happen at certain ranges temperatures. Like for example what makes cooked food tasty is the carmelization of proteins and sugars. You need a certain temperature for it happen (like for example ice does not become water until 32 F or 0 C), but if you go to high the proteins and sugars just turn to ash (like for example if you heat up ice too fast, it quickly turns into vapor instead of lingering as water)\n\n3) Temperature is more of ranking system than number that tells you amount of something. Like for example if I told you that the 5th runner beat the 6th runner, it tells you nothing about how much time the 5th runner beat the 6th runner by. It could have been by 1 second 10 minutes or 50 days. The same applies to temperature. 100 degrees Kelvin does not necessarily mean that something contains 1/10 the amount of heat energy as something that is 1000 degrees Kelvin. ",
"The main reason is conductivity. Some things absorb heat faster or slower than other things. If you add too much heat too quickly then sometimes the fringe of whatever is being heated up will heat up so much faster than the other parts that it becomes more heavily altered than was anticipated or desired. Think of burning the exterior but having an uncooked interior. On a slower heating the object is more likely to be homogeneously heated, on higher temperature it's more likely to be heterogeneously heated. They are different. ",
"imagine you are pouring water into a sink, the drain isn't very fast so if you turn your water on high you see the water level rising, but if it's really low the drain keeps pace with the faucet.\n\nwhen you heat something up you are doing this, but with heat. everything loses heat to the environment, how much and how fast depends on the material and the environment, and different things take in heat at different rates as well. so if you take your steak, which isn't a very good conductor of heat, and take a blowtorch to it you will get it very brown, or black, on the outside but raw on the inside. you can cook it at a lower heat and it won't get as hot but it will cook more thoroughly. this is kinda like blasting your sink with a power washer, water goes everywhere but little sticks around.\n\nthen you have something like caramelizing sugar, if you put the heat too low it will lose heat to it's environment too quickly and not reach the temperature you want it at, you have to either reduce the drain (such as putting it in a kiln or oven) or increase the faucet (by turning up the heat)"
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[
"https://en.wikipedia.org/wiki/Activation_energy"
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"https://en.m.wikipedia.org/wiki/Maillard_reaction",
"http://imgur.com/xsxoCqV"
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5ea8qt
|
why do airlines ask you to turn off/airplane mode your phone during a flight when? does it actually affect the flight?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5ea8qt/eli5_why_do_airlines_ask_you_to_turn_offairplane/
|
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"planes used to use technology that was affected by certain radio waves a cellphone might give off. This isn't really the case anymore, but airlines take a very long time to change any of its rules. security concerns and what-not. ",
"This is because not all signals from mobile phones have been proven to not affect airplanes in any way. Proving that would cost a lot of time and money so they simply don't bother. \n\nThe signals most likely don't affect modern planes at all, but airlines don't want to risk the small chance that they do affect the plane in any way. ",
"Think about it this way. If there was even a real 0.01% possibility that a mobile phone signal could bring down a plane, they would be included on that list of prohibited items the check-in desk attendant asks you to verify. You wouldn't even be allowed to carry them into an airport. Look what they did with the Samsung S7.",
"Please see [these prior threads](_URL_0_) for other discussions on this question. ",
"Have you ever had an old cell phone next to a T.V. and it rang? That annoying static? I always assumed that was the reason. It's interesting to read other comments though. ",
"Regardless of whether or not a phone affects the aircraft, I like the fact that I can get on a plane and not have to listen to loud and obnoxious people yelling into their phones. Generally people talk to each other in hushed tones on a plane. Never on a phone though.Could you imagine a redeye flight with oblivious jerks keeping everyone awake. I hope they never change the rules.",
"I fly weekly and I never turn off my phone or switch to airplane mode. If it was even remotely possible for a cell phone to cause a crash, you wouldn't be allowed to take one on the plane. ",
"Mythbusters did some limited tests on this. Problem was the FAA wouldn't let them do it on a flight, so all results with a pinch of salt. \n\n\nWhat they found between experiments and research is that yes, mobile phone signals can indeed interfere with aircraft instruments. More-so older aircraft since newer ones have much better shielding. \n\nHowever, given the huge number of planes in service, of varying age (so no guarantee the shielding is still intact) multiplied by all the different phones coming out with 3G/4G/H/Bluetooth/Hyperwave it is utterly impractical to test all phones on all planes in all conditions to be sure that it is safe. So, the default option is to tell people to turn devices off. ",
"I've seen discussions before on this and iirc the flight attendants have always said it has nothing to do with the plane, but more because take off and landing are the riskiest parts of the flight, if anything is going to happen it's going to happen then. That being said, they want everyone's full attention during those times and not on their phones",
"I'm a pilot. While usually cell phones don't affect our instrumentation (anymore, this wasn't always the case), I can definitely tell if someone in first class (or in the cockpit haha) has their phone on because as soon as we get low enough for them to have service, I will hear a bunch of clicks in my headset if they get a message or something. It's mildly distracting but nothing else. I know that doesn't really answer your question ",
"Many wrong comments. The real reason is the frequencies your phone uses cause interference in the radio for the pilots and it gets annoying for them. Ever keep a phone near a large amp? You will hear a noise everytime it looks for a signal or a call comes.",
"Plane electronics use AC circuits that operate around 400 Hz or so verse the 60/50 Hz of normal circuits. This is because higher AC frequencies can use smaller transformers for a given amount of power. As your operating frequency decreases, the size of any passive components you use must increase. \n \nThe GSM standard used by cellular devices emits a distinct signal that is effectively around 200 Hz when handshaking with the tower to receive a phone call. This creates a problem for aircraft electronics because that 200 Hz signal can couple through holes in line shielding, and potentially cause the power supplies of various circuits to malfunction. \n \nNow you're probably going to ask--why not just filter everything above and below 400 Hz? \n \nThe answer to this question is more complicated. 400 Hz is within a single octave of 200 Hz (An octave is the difference in frequency between 1f, 2f, etc). Electronic filter complexity is proportional to the roll-off. Roll-off is the slope you get when you plot the attenuation of an electronic filter against the operating frequency. \n \nSo to get a suitably steep roll-off within the first octave such that it might protect the aircraft from your phones GSM buzz, they would need complex electronic filtering circuits, with unreasonably large, heavy components. On top of this, filtering signals above 400 Hz, also makes things more complicated. \n \nWill time march on? Certainly, that's all it ever does. Integrating power conditioning and signal processing into sensors and controls, so that they send all their information digitally, will fix this issue if it hasn't done so already. Changes in transmitting protocols will also improve things \n \n\n ",
"The real reason we have to turn off our phones: the airline industry knows how dreadful flights would become if you had to sit next to someone chatting on their phone for 4 hours. And they are right.",
"The FAA has no regulation regarding cell phone usage on an aircraft, as cell phones, with wireless communication, fall under FCC. The FCC has these regulations in place, not due to interference of aircraft avionics, but because when you are above the Earth's surface, your phone is able to connect to a larger number of ground based cell towers than if you were on the surface. This can cause performance issues of cell networks in the area. There's more to it, but this is why you aren't allowed. Not FAA. Not Airlines. FCC. ",
"I'm a pilot. The concern by the FAA is that certain electronic devices (like cell phones) have electronic components which may interfere with the VOR receivers that many airplanes used to use to navigate the U.S. airspace, as well as the ILS receivers used to help airplanes navigate towards the landing strip. This is done through an overabundance of caution; normally there is no interference, though we did have one airplane in our flying club where a cell phone did screw up the VOR receiver. (The electronics on that older radio were not properly shielded.)\n\nIf you are navigating by VOR and the VOR receiver is off, it's pretty easy to get lost up there.\n\nNowadays with almost everyone using GPS to navigate, there is less of a concern, though [airplane pilots still do occasionally get lost and land at the wrong airport.](_URL_1_)\n\nIt's in large part why you used to have to turn off all electronics below 10,000 feet: because that's generally during the approach or takeoff period where you are using the ILS receiver to guide you to the landing strip (and through potential obstacles like mountains and tall buildings), and in areas like Los Angeles, where there are tall mountains where navigation is vitally important. (Also, when there is a problem the airplane becomes a glider; the lower you are the less time the pilot has to deal with the emergency, so there is less margin for error when you're below 10,000 feet.)\n\n(Edit: Holy cow, I didn't expect to get this much response! Goodbye, mailbox!)\n\n(Edit 2: So I forgot to define my terms. Which makes sense because I had no idea this post would take off.\n\n\"VOR\": [VHF Omni Directional Range.](_URL_2_) It's a type of navigation aid which transmits a signal that can be received by a special receiver in an airplane, that allows you to determine your angle relative to the VOR transmitter. Using two VOR transmitters at separate locations a pilot can (in theory, if he remembers how) determine his location by using two separate VOR receivers.\n\n\"ILS\": [Instrument landing system;](_URL_0_) it's a special transmitter which allows a pilot to determine his relative location to the landing path he needs to follow to land on a runway. The ILS system transmits two signals; one which allows a receiver to determine his relative angle horizontally to the landing path; the second determines his relative height above or below an ideal glide path. It's commonly used by commercial pilots to help glide their aircraft to the touch-down point on the runway, and is used by pilots flying in instrument conditions (where you can't see anything outside the window) to land successfully.\n\nAlso I see a lot of comments talking about \"well, if this is true, why doesn't the FAA do this or do that?\"\n\nMy two responses are:\n\n(1) You're expecting the FAA to make sense? Optimism.\n\n(2) Remember: the FAA isn't happy until no-one is happy.",
"As an aerospace engineer, I can tell you the affect on modern planes is minimal, if anything. However, mobile phones serve as nothing less but a distraction, especially of there's an emergency where passengers need to pay attention to the crew.",
"10 years ago, did you ever put your iPhone too close to a computer speaker or radio alarm clock? If you did, you could hear this series of tones and clicks as the phone talked with the towers over GSM. I never thought much about it until my flight instructor didn't turn off his phone during a cross country trip. When his phone started talking to the tower those tones were magnified over my head set to the point where they were almost painful.\nLoud and obnoxious. None of the instrumentation seemed to be affected, though. Most phones are better made and talk on different frequencies now, so not anywhere close to being the same annoyance. But, none of that 10 year old tech is gone. Most of us have moved past it but it is all still around and somebody could bring one of these old phones onto a plane.\n ",
"Flight attendant friend told me that majority of flight emergencies happen during take off or landing. She said the phones off under 10000 feet rule is a leftover from tech interference issues that is kept just in case but mostly now so people will do what they are instructed instead of calling someone or texting or filming or whatever. ",
"Dad has been a pilot for thirty years. The biggest reason is the same as why you have to have your seat up, your luggage under the seat, the blinds open, etc. -- they want everyone paying attention and unencumbered in case there's an emergency during takeoff or landing.",
"Holy Misinformation Batman!\n\nThere is a good summary of this on SKYbrary [_URL_4_].\n\nThe original ban was based on the sterile cockpit rule [_URL_1_] and FAA guidance on use of portable electronic devices (PEDs)[_URL_3_].\n\nAfter a 2013 report from the PED Aviation Rulemaking Committee (ARC) [_URL_2_] clarified that the concern was overstated and that aircraft that have been appropriately tested for immunity to electromagnetic interference are not at risk, the FAA guidance was revised [_URL_0_].\n\nSeveral systems now allow \"gate-to-gate\" operation where use of PEDs is allowed during all flight phases.",
"Lived with a pilot:\n\nHe tells me it doesn't interfere on the new aircrafts and he never turns his off.... \n\nHe said they still like to tell people just so they actually listen to instructions taking off and landing. ",
"I'm a pilot. The short answer is:\n1) it doesn't.\n2) ...but there have never been legit tests to prove that it doesn't.\nThe FAA as a rule is extremely risk-adverse when it comes to new technology. I would even say that if the Wright Bros discovered airplanes when the FAA had their mandate they never would have been allowed to continue. \n\nAnyway, the way I understand the story went, when cell phones became a thing, the cell networks were fragile, weak, and couldn't handle a lot of capacity. A cell phone at altitude had line of sight to more towers, which in turn tied up more of that already low capacity than it otherwise would. So when the FAA was considering what to do about this new technology on flights, the lobbyists from the telecoms nudged them towards what they were already instinctively preloaded to do - ban them.\n\nThen most of the nations that take the lead from the FAA did the same thing and boom - no cell phones on airplanes. They did finally come around to electronics being on, but it took them twenty years to even look at the problem. It will be awhile till we're allowed to make calls inflight.",
"This [video](_URL_0_) sums up my question",
"I've personally had an iPhone (incoming call) interfere with the Instrument Landing system ([ILS](_URL_0_), the thingy that helps me find the runway when in fog), while coming in for a landing. You sure don't want your ILS being messed up when you are coming in to land with low visibility. \n\nI've also had friends who are pilots who've had phones messing with their VORs or ILSs.\n\n\n",
"They are just being overly cautious. The \"studies\" have been done. Cell phones have been around for decades. It is statistically guaranteed that hundreds or thousands of flights happen every day where people don't turn on airplane mode. If it was really a problem we would have seen the results by now.",
"This is coming from a pilot. Cell phones can influence navigation, especially on long flights. What happens is the electromagnetic effects your phones have can move the compass slightly. At least that is the official reason(that and terrorism). But in reality your phone needs to be ON the compass, like your phone can't actually tweak the compass unless you walked in the cockpit and laid your phone directly on it. But in todays modern air craft here is bunch of redundant systems so GPS, the tower, and other instruments would still keep you on track.",
"My cousin is a flight attendant, and she was trained that while cell phones don't mess with the plane working properly, they are a distraction incase of an emergency. That's also why they have you put everything up while taking off and landing. If the plane crashes, you'll be more alert, and things won't be flying all over the plane interfering with escaping.",
"The FAA, FCC, and Amazon filled an airplane with fire tablets all on and not in airplane mode and they measured the interference. The results were that the interference so minute that there is no way it could effect the systems on a plane. The FAA has since changed the rules regarding electronic devices but the airline's have yet to adopt the new standards. I get the feeling that some flight attendants just enjoy telling people what to do.",
"Okay well I'm late to the party so this won't go anywhere, but I see a lot of okay answers, a lot of speculative answers, and a lot of dangerous answers. As a former airline pilot, let me try to break the issues into a few categories: \n \n1. Interference to navigational equipment. As others have said, a cell phone could potentially cause a minor deflection on navigational equipment. Where this becomes most relevant is in the landing phase, especially in bad weather. What I think most people don't understand is exactly how precise the instruments are. \n \nHere are some examples of how close the instruments bring an airplane in to landing: \n \n* What's called category 1: a layer of clouds 200 feet above the airport and 1/2 mile forward visibility. This is able to be flown manually by the pilot. [Here's a video to show you how little time you have to react once you can see the ground](_URL_0_) \n \n* What's called category 2: a layer of clouds 100 feet above the airport and 1/4 mile forward visibility. The approach is typically flown by autopilot now but manually landed. [Here's a video to show what that looks like](_URL_2_) \n \n* What's called category 3: For all intents and purposes this is no visibility. This is fully automated. [Here's a look](_URL_1_) \n \nNow, to give you an idea, these systems are putting an airplane travelling at nearly 175 MPH onto a piece of pavement that is generally 150 feet wide. The localizer, which is a component of the Instrument Landing System (the ILS some others have mentioned) shoots a beam which does this laterally. At the runway's end, this beam is 750 feet wide. \n \nThat means that in the cockpit, if the indicator is even a little off, you're going to land in the grass. \n\nAnd if you land in the grass, you're gonna have a bad day. \n\n2. As others mentioned, there is radio interference. Hearing the cell phone clicks over the headphones could cause the pilots to miss valuable instructions from air traffic control, which could lead to you flying into a mountain or another airplane. \nAnd if you fly into a mountain, you're gonna have a bad time. \n \n3. But the most important thing that people ignore here is SCALE. Sure, one person may leave their cell phone on for a flight in good weather conditions, but if you had 150 cell phones on during a flight, the navigational error may be larger. It may not matter on most days, when the weather is not an obstacle and approaches are done \"visually\" with the pilot navigating to the runway by just using his eyes, but it will matter when you get into the bad weather that you see in the videos above. \n \nAnd to all of those who said \"Well I leave my cell phone on and I have never crashed\" you should really rethink your strategy. If I eat raw chicken and don't get salmonella, does it mean that you can't get salmonella from eating raw chicken? **NO IT MEANS YOU GOT LUCKY.** And so if you want to gamble on your plane not crashing so that you can get that extra three minutes of text messages in (because as others have noted, signal is garbage at altitude because of tower switching), then keep in mind there are hundreds of other passengers on the airplane who would prefer to probably live their life. The idea of text messages vs a 1/10000000 chance of dying being an acceptable trade off is an embarrassing state of our society. \n \nEdit: Thanks for the gold, but really, I would encourage you do go do something better with your money like gamble on monkey knife fights or something. \n \nEdit 2: seriously, stop with the gold nonsense. \n \nAlso people have accused me of scaremongering: rest assured the odds of crashing are incredibly small and a cell phone won't increase it that dramatically, I just have to emphasize to the \"WELL, I CAN USE MY PHONE BECAUSE THE RULES DONT APPLY TO ME\" crowd that the rules exist for a reason. ",
"It's actually an FCC regulation, not FAA. If I remember correctly a cell phone attempting to connect to towers at airplane speeds, rather than highway/car speeds, can create a huge resource burden on the towers.\n\nSource: _URL_0_\n\n^^^^^^linked ^^^^^^from ^^^^^^mobile",
"Airline Captain here. \nI have a answer that gets people to not use their devices in the air. \nWhether it affects aircraft systems or (most likely) not, it's legislated in most nations; making the question a legality one. \nBut like most folks, passengers will decide on their own when they're ready to put their device in flight/airplane mode. \nHere's what I tell people that ask me that exact question. \n\"I don't know for sure how it affects flight parameters, but I'm told that phone numbers (or SIM data) could be retrieved for liability reasons, in the event of an accident.\" \nI normally don't get a follow up question. ",
"I've heard they don't let you use electronic devices also, because during take off and approach, is the time when there is more chance of having an emergency and people should be fully aware to evacuate or act accordingly, so, as a mean to not get distracted, they just forbid you to use any electronic device. Just imagine if there's an emergency and the guy beside you has his laptop open or is listening to some music and oes not notice... evacuation would be more difficult.\n\nBut I'm no pilot though, somebody correct me if I'm wrong.",
"The interference is rare and doesn't bring down a plane on its own, but it can distract pilots during critical parts of the flight like takeoff and landing. You don't want a distracted pilot. People accidentally leave their cell phones on planes quite often, and those phones continue to emit interference until discovered or battery drained.\n\n_URL_0_",
"Why are there so many flight crew on reddit? Everytime there is a pilot or flight attendant question it seems to hit front page with over a thousand responses to some random flying question. This is not a forum i would have expected so many flight crews to hang out on.",
"With all due respect to all the pilots commenting, a majority of the info they give is regurgitated from FAA BS. There was one pilot comment I saw that said it doesn't affect the plane, that guy knows what's up.\n\nThe FAA only gives excuses as to why you should turn off your phone. The FCC is the organization that actually initiated the practice of turning off cell phones.\n\nIf you could bring down a plane with a strong cell signal, there would already be devices designed to do that. Terrorists could even send them via airmail and take cause huge air traffic disruptions without ever stepping foot on a plane, or even on US soil.\n\nThe truth is that turning off your cell is done to prevent DOSing cell towers. Every time you move to a new area, your cellphone has to seek out and sign on to the cell towers in range. This is constantly being done by your phone in the background as long as you have your cell service on. Now imagine 300 people moving at 400mph from tower to tower signing on to a new tower every couple of seconds. They could hand one or two planes, but soon enough the networks would not be able to keep up.",
"Cellphones can't bring down planes. If they could, terrorist could simply crash a FEDEX flight using them via air freight. If that was possible, you wouldn't be allowed to bring a cellphone on board AT ALL unless it was confiscated. The purpose of turning off a cellphone is so you don't hijack cell towers and overload them.",
"Airline pilot here disturbed by all the people especially other pilot colleagues downplaying this. \n\nThere are hundreds of reports of interference issues. I've experienced a handful myself. [These](_URL_0_) are just a tiny sample.\n\n_URL_1_ has many more.\n\nHas anybody dies because of this? No. Is the likelihood slim? Absolutely. Is it a non issue? Absofuckinglutelynot. Accidents happen due to a chain of events. It's only pure luck so far that there hasn't been an accident attributed to PED interference so far.",
"Its harder to notice these days with common electronics, but earlier in the days of cell phone technology - you could hear interference from nearby cellular equipment and phones over analog radio devices. This was especially true for \"regular people\" if you had your cell phone with you in the car with the radio on, etc. Particularly, incoming signals (especially text messages) would cause clicking or beeping noises to be heard. This was even true if a device was close to a television. Anything with a basic/primitive audio system was highly susceptible to interference.\n\nI believe this is because a majority of electronics device are not allowed to be shielded from outside interference per government regulations - and therefore can be overwhelmed by other strong local radio signals and power sources.\n\nOver the years as the cellular bands (E - > 3G - > 4G - > etc), phones have become less and less noticeably interfering with other devices. Airline cockpits have also become increasingly shielded and filtered from outside interference.",
"I'm a private pilot, which means I fly small planes.\n\nWhen I started learning several years ago, I had phones that weren't smart phones (flip phones, side kick, etc). These phones would interfere would our VOR receivers and our comm receivers. What this means is that every time I get a text or a call, I'd get static noises and clicks in my headset (similar to if you put your phone next to your speaker, there's static). Our VOR receivers would stop tracking for a brief moment and/or there would be interference. \n\nHowever, with new smartphones (I've used several iPhones and a Galaxy S3), this doesn't really happen at all anymore. I get no more clicks or interference (and it's still the same type of airplane). \n\nSo maybe when this rule was invented a long time ago it was more crucial to turn phones off. But these days the FAA is less strict about this rule, possibly due to new phones which means less interference. ",
"I am an electrical engineer (degree, not job) and right out of college I got a job at an electronics testing and certification business that among other things tested civilian and military aviation equipment. The certifications that are required by law to sell a device in the US require that the device can accept interference and does not cause it's own interference with other devices. Since the regulation forces a device to protect itself and essentially protect other devices as well, it would require both devices to have issues for there to be a real problem. If you are sitting on a plane that we built in the 70s etc maybe (don't know history of these laws) there is an issue if it still contains the original electronics. Anything moderately modern should be safe. Modern airplane equipment has all passed these regulations so they should be able to accept interference without bringing the plane down. At that point you only have to worry about \"rogue\" \"consumer\" devices. There will be devices on planes that are not marketed to the US or other western nation and therefor may not have the same stringent requirements. But even if you had a bad device that emitted \"signals\" outside of it's operating range or levels the planes equipment should still withstand the interference because it is designed to do just that. The only viable way to cause interference in a modern plane in my opinion would be to create a device that was specifically designed to interfere with and take the plane down. In that job I have handled equipment that could take a plane down. The power source required to power such strong devices would have to be rather large to make it mobile. Like \"there is no way in hell TSA is letting that thing on a plane\" large.\n\nTLDR: Your cell phone will never take down a modern plane. It would take something much more powerful to even come close. Thanks regulations!\n\nEdit: I forgot to mention you could also have the scenario where you have a bad consumer device (non-regulated) and a plane with equipment that has manufacturing defects that cause it to not adhere to the FCC regulations. That would be a perfect storm but I do think it is within the realm of possibility. With redundancy in equipment and the testing that should be happening on devices after they come off the assembly line, this should not be really be a reasonable concern.",
"Source - I'm a hobbyist pilot and full time engineer working on network devices.\n\nWhen mobile device have a weak connection they will transmit more power. During the high speed of a flight, and on high heights a mobile connection is not posible (i think) because you move fast relative to the signal (think about this like a fast car is passing and it seems like the tone of the car changes, but it only changes because the distance between you and the car changes) and also your place changes to fast and the network is expecting you to be in a certain location, and is transmitting your data in that direction. So turning data connection off doesnt matter anyway, as you wont be able to have a valid connection and your phone will only search for it.\n\nHow ever, the moment your phone has a valid connection again will be the moment that your phone has to transmit all kind of stuff. First info of your personal phone, identifying the in the network, security etc. Then after a valid connection is ok your device will update all apps in the background like avalable messages, your email etc etc. This cause a high peak in the network use. Not only your device is doing this, but all 300 other users will connect at (about) the same time because all of them are getting back in connection at once (should be some time diffrences as not all phones have an equal connection/operator etc). However, all these phones combined, starting to update at the same time, will make a high peak in transmission.\n\nHowever, airplanes should be designed that this could not be a problem. Don't expect an airplane to crash just because of this. Hardware should be designed to work with this and use diffrent frequencys.\n\nOne example about how much energy is transmitted during an phone connection. Remember those old phone stickers with a light in it that blink when you call without connecting it to a battery? ",
"My mom is a flight attendant. Phones are a distraction to crew safety instructions during take-off and landing. Having your seat up also makes passenger escape easier.",
"I'm an Airbus A320 pilot, but most of this applies to any modern aircraft.\n\nYour phone (or iPad, or laptop...) can't interfere with any of the fly-by-wire systems on the aircraft. Ever. Simple as that.\n\nWhat it can interfere with is the very sensitive navigation radio receivers (specifically, the ILS localiser, which gives lateral position guidance on approach).\n\nSome UK airlines now allow you to keep stuff on for take off and landing (they ask you to put it in flight mode so it doesn't upset phone companies or cause that annoying buzzing in my headset). However, if we're planning to perform an automatic landing in poor weather conditions we'll ask you to switch it off completely as it's my preference to land on the runway, not the grass next to it (as Singapore Airlines demonstrated in Munich recently).\n\nHope this helps.",
"Everyone brings up potential interference. But theses technologies all work on different frequencies and the FCC certifies all electronics to not output extra on unintended frequencies. \n\nThe real reason was that MCI noticed in the mid 90s that the towers near airports were unstable. This was caused by the way the towers predict when and how to hand off a connection to the next tower. \n\nWhen a plane took off it was going really fast and the towers would try to hand off the phone to the next tower in the line really fast. This could cause a cascade effect in the towers down the line expecting a phantom device to connect. The ate up a lot of processing power on the towers and could cause other calls to drop, phones to be disconnected, and towers to completely lockup.\n\nMCI wrote a report for the FCC outlining the issue and demanding that phones not be allowed on aircraft. Arguing that it could pose a risk to people on the ground if they were trying to call or currently on the line with 911. The FCC stated that cellular phones at the time were already not a reliable way to contact 911 and that they had no way to regulate their use on aircraft as that was up to the FAA, and told them to fix the issue in their towers as not all towers had an issue. The simple fix was to make it that if a phone was calculated to be going over about 75 mph to just disconnect it from the towers.\n\nMCI didn't want to invest the resources in engineering a fix, so they then submitted their argument to the FAA but removed the reasoning behind how it could be a threat and to whom it was a potential threat, still noting that it was only an issue if the phone was in an active phone call at the time of takeoff. Leaving it open to interpretation that the ever cautious FAA took to mean a threat to aircraft. They banned cellphone usage and saved MCI some engineering costs for a few years.",
"I remember once hearing that part of it was the carriers were pushing for the practice because having hundreds of phones jumping towers quickly caused problems for the network. Don't know if that's accurate but it's something not usually mentioned in these discussions.",
"Real reason?\n\nBecause they want you to pay attention to the cabin crew, and the safety briefing.",
"Pro-Tip: Putting your phone in airplane mode will save you a TON of battery life as you phone will drain searching for towers.",
"I asked a pilot this once and he said it had no major effect as people do it anyway. The main issue is the vast acceleration in technology changes and the required testing the FAA would have to go through for every new technology that hits the market. In lieu of spending time and money every year when a new tech cones out the safest bet is just to ban cell phone use in the air.",
"On the phone side of things airplane mode helps you conserve battery. When your phone goes outside the reachable network it will work harder and harder to try and stay in connection with that network. Searching for a cellular network will eat up a lot of battery but airplane mode halts any searches for networks from the phone. ",
"One time on an international flight, I sat next to a guy who turned out to be a pilot headed somewhere to do a private piloting job. So I took the opportunity to ask him if putting devices in airplane mode really matters. He laughed and said it doesn't do a damn thing.",
"Typically they want you to turn your phone off during the takeoff/climbout and approach/landing phases of flight.\n\nNo, it doesn't affect the systems of the airplane. The only instrument that digital devices can reasonably affect is the magnetic compass, because of the device's own magnetic fields, and that only happens when the device is very close to the compass, within about a foot. All the other navigational equipment is very well insulated from electromagnetic interference. Radio equipment like the radios, VOR and ILS receivers won't be affected by passengers in the back. We pilots are trained to simply not set our phone on the glare shield next to the compass or VOR, etc. Pretty simple.\n\nThe main reason they still do it is to reduce distraction in the event of an emergency. If an emergency happens at low altitude, there is very little reaction time available to solve it. The flight attendants are trained to prep the passengers for evac very quickly, and they need the passengers to be alert, prepared, and to simply follow directions.\n\nSource: I'm a commercial pilot in training and am also familiar with the training and duties of flight attendants. They aren't just there to serve you Coke, they're there to keep you alive when it counts. My job will be to give them the opportunity to do their job. ",
"Radio technician/pilot here. The vast majority of commercial aircraft built in the past 15-20 years have shielded wiring... this means that all critical electrical wiring has metal mesh surrounding it. Remember those science experiments where they put someone in a metal \"Faraday\" cage and shock the cage with electricity? EMI (electromagnetic interference) shielding operates on the same principle. It is unlikely that an airplane full of cell phones would have any effect on the aircraft's critical systems... in fact, some modern aircraft (primarily private jets) are built with a mini-cell phone tower (also known as a picocell) on board so that cell phones can be used in-flight.\n\nOne of the primary reasons that the FAA keeps the cell phone ban in place is the FCC (Federal Communications Commission)'s regulations. If a cell phone is left on during a flight, it has to switch from cell tower to cell tower every minute or so - each of these 'handoffs' takes up network resources and requires messages to be propagated throughout the national cell phone network. Now imagine what would happen if every one of the tens of thousands of daily airline passengers left their cell phone on, each jumping from cell tower to cell tower every minute... it would result in millions of handoffs and wreak havoc on the cellular networks (or at least slow them down considerably).\n\nI should also acknowledge what other pilots in this thread have pointed out, which is that a plane full of cell phones could indeed screw up some of the older technologies used during approach and landing, the primary one being ILS (as mentioned by the other pilots in this thread). ILS is an oldddd, old technology (first tested in 1929... not kidding), and is analog, not digital. It is, however, still used at nearly every major airport as a backup to GPS (and, in some cases, as the primary approach guidance). Significant radio interference could indeed mess up the receiver, particularly at the beginning of the approach when the signals are weakest.",
"It's strange to me that smartphones are risky enough to warrant a constant reminder/rule every flight, but not risky enough to be abolished outright. \n\nThey are essentially the *running with scissors* of air travel?",
"I'm an aerospace engineer, pilot, and have held aircraft maintenance qualifications.\n\nMore relevant for this conversation, I have spent several years of my life running aircraft testing to confirm their safety with cellular phones (and other consumer devices) in all phases of flight (including take off and landing), providing input to the FAA working group and to several other regulators on setting requirements around the use of TPEDs (transmitting portable electronic devices) on board, specifying software changes for MIS (maintenance information systems) to ensure that compliance can be maintained, and developing alternate testing processes, creating risk assessments, etc.\n\nYou do not endanger the flight by having your cell phone on during flight.\n\nThe reasons you are asked to put your devices into flight mode are:\na) Your airline hasn't jumped through one or another regulatory hoops set by their regulator (note - not jumping through a hoop or two does not imply any 'not safe' condition on the aircraft), or\nb) Your airline wants to minimise 'air rage' where passengers make (or try to make) voice calls in flight.\n\nReason b) is the reason my airline continues to request devices are put into flight mode.\n"
]
}
|
[] |
[] |
[
[],
[],
[],
[
"https://www.reddit.com/r/explainlikeimfive/search?q=Phone+plane&restrict_sr=on"
],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[
"https://en.wikipedia.org/wiki/Instrument_landing_system",
"http://www.cnn.com/2014/01/13/travel/southwest-plane-wrong-airport/index.html",
"https://en.wikipedia.org/wiki/VHF_omnidirectional_range"
],
[],
[],
[],
[],
[
"https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_91.21-1C.pdf",
"https://en.wikipedia.org/wiki/Sterile_Cockpit_Rule",
"https://www.faa.gov/about/initiatives/ped/media/ped_arc_final_report.pdf",
"https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_91.21-1B.pdf",
"http://www.skybrary.aero/index.php/Use_of_Personal_Electronic_Devices_(PEDs)_on_Aircraft"
],
[],
[],
[
"http://www.collegehumor.com/video/6905768/why-cant-you-use-phones-on-planes"
],
[
"https://en.wikipedia.org/wiki/Instrument_landing_system"
],
[],
[],
[],
[],
[
"https://www.youtube.com/watch?v=9OJkq1_omwg",
"https://www.youtube.com/watch?v=UV_vWtAJIow",
"https://www.youtube.com/watch?v=1d0cIM_1vZ4"
],
[
"https://en.wikipedia.org/wiki/Mobile_phones_on_aircraft"
],
[],
[],
[
"http://www.cnn.com/2013/09/23/travel/cell-phones-devices-on-airplanes/"
],
[],
[],
[],
[
"https://asrs.arc.nasa.gov/docs/rpsts/ped.pdf",
"https://asrs.arc.nasa.gov/"
],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
||
5eq9wc
|
how the uk government will be able to see all of people's internet history.
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5eq9wc/eli5_how_the_uk_government_will_be_able_to_see/
|
{
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"text": [
"When you access a website, you send the request via your internet service provider; all these website requests are logged by the ISP, which the government can then request. For websites that uses HTTP, everything can be logged. Sites that use HTTPS will encrypt the content of the site so that you can't be snooped on, although the websites address can be logged. A VPN would be required if you wanted privacy, as this would encrypt everything and make the request you send via your ISP unreadable, but your VPN provider could also snoop on you."
]
}
|
[] |
[] |
[
[]
] |
|
1956bs
|
why porn is bad for me
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1956bs/eli5_why_porn_is_bad_for_me/
|
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"Probably not the answer you're looking for: It's not. ",
"It changes the expectations on what is and isn't sex. Many things in porn are there because they look good, not because they feel good. \n\nIf you are over 18 and not at work, check out this iconographic: [NSFW](_URL_0_).",
"There was a fairly popular post a week or so ago (I think in [/r/AskReddit](_URL_0_) ) that asked how porn influenced people's views of sex. Overwhelmingly the stories were how porn had a bad influence in terms of expectations and things like that. Unfortunately, I searched for it but couldn't find the post. If you can find it, it is worth reading.",
"check out /r/nofap or /r/pornfree for more answers to this sort of question. You'll get lots of testimonies there.",
"In the same sense that watching shows about the lifestyles of the rich and famous is \"bad for you\"; it can shift your expectations of what is achievable to you. Essentially it is the same argument which is leveled against violent movies and video games.\n\nFrankly I think it is hogwash.",
"Well buddy, this is gonna sound pretty gross, but when a man and a woman love each other very much, or are very drunk, they have this thing called sex. Sometimes this is a wonderful, intimate experience fueled by trust, and other times it's a wonderful, but one-off experience, but regardless of the case, it's about multiple people enjoying themselves.\n\nThe difference is that porn isn't about the ones having sex enjoying themselves; it's about the viewer enjoying themselves. Because of this, in most porn, the positions, attitude and overall atmosphere is quite different from that in the case of 'real world' sex. Because of this, if you were to watch pornography, you may be influenced to think that this is how sex should be, and as a result you could find yourself not enjoying what should be a fantastic experience. Remember, in 'real world' sex, you're doing it for you, not the onlooker, and so it has to be done differently.\n\nIt may also give you the wrong idea about how to treat your partner. Although some insist otherwise, in *a lot* of porn, the female isn't exactly treated very nicely! If a very young girl watches porn, she may begin to expect to be treated like that by all men; if a young boy watches it, he may start thinking that that's how he's supposed to treat women.\n\nFurthermore, there are some who think that it can harm your ability to have sex. See, to have sex, you need to... erm... well, your willy needs to be hard. I know, it's weird! Well, there are many who say that, if you watch pornography at a young age, then you may start moving on to what we call more 'hardcore' material. This may mean that by the time you start having sex, you'll be so used to getting pleasure from watching this hardcore material, that 'regular' sex may bore you, and you'll struggle to keep your member hard, as you'd have become so used to more extreme presentations of sex.\n\nNow, all this sounds odd to you, I'm sure, but one day it will make sense. You should know that, while many say that porn is bad, sexual urges (the things that let your willy get hard) *are not* bad, and not anything to be ashamed of. In fact, as we've discovered, the reason that porn is considered bad by many is because if has a negative affect on those urges. So don't be ashamed of that, but just remember, if you do watch pornography: it's *all* an act, and although it may look fun, the real thing is nothing like porn, and it is far, far better.\n\nNow here's some money, kid, you run along and get yourself an ice cream now. I need to go talk to mommy about something.\n\nEDIT: Jeez, go to sleep and come back to a lot! Of course, thank you very much for the Gold, whoever you are! I'll also say here that these are simply theories I've heard, I'm afraid that I am not really at liberty to debate many. I understand the logic behind them all, but there are people out there that know a lot more about it all than I do.\n\nI'll also say that I do understand that the ELI5 part isn't necessarily meant to be taken literally, but I just wanted to have a bit o' fun with it, happy to see that my little piece was enjoyed by so many!\n\nEDIT 2: \n\n > Little piece enjoyed by so many.\n\n... Y'all know what I mean.",
"Porn itself is not bad for you but it is important to think of it just like other movies. When we watch a movie we know (or your parents should have told you) most of the time what the actors/actresses do in a movie does not happen in real life. \n\nThere were a lot of smart people to help them and made the movie look interesting. In porns, actors may take drugs to make the movie last longer, and make loud noise to make it more interesting or they could take breaks in between. It is important to know the different because if we blindly follow what the actors did we (or someone) could get hurt and we don't want that.",
"After dating a guy (who is now my ex) that basically educated himself about sex through watching porn, I can definitely say that it lead him to equate the fact that I didn't orgasm during sex meant that I was not attracted to him/turned on by him, which was completely untrue. He eventually pressured himself (and me) in bed so much to orgasm that I started to view sex with him as something where I knew I would let him down every time. This tremendously affected our relationship as a whole, and coupled with a few other reasons, lead to our eventual breakup. Moral of the story? Feel free to watch porn, but take it with a grain of salt, and never apply it to real life.",
"OP-- try to avoid loaded questions. We're not removing this, but still. Next time, perhaps do \"ELI5: Why many would argue porn is bad for me.\"",
"In a same way violent movies are \"bad\" for you. If you are less than intelligent, or not fully mentally developed, you might get some stupid and wrong ideas about life and people in general. \nMasturbation on its own in the other hand is not considered \"bad\" in most cases. You might be missing out, though. ",
"This is actually a really good discussion. Good Job Reddit.",
"Here's a different take that was covered in /r/infographics a little while ago here: _URL_0_\n\nYour brain makes a chemical that makes you feel good. It's called Dopamine, and people do all sorts of things to get that feeling. When you watch porn, your brain makes this happy juice in a much different way, and in higher quantities than when you're having actual sex. Because of this, over time you desire this feeling more than an actual relationship. Porn in and of itself is not \"bad\" for you the way most other bad things (like drugs or smoking) are. It's bad because it makes you less interested in good things, like getting laid.",
"Porn has become more of a modern day circus side show than anything to do with normal sex. Hard core porn's appeal comes from the crazy shit done in the video than anything any sane person really wants to do or have done to them.",
"I'm a bit late to the party but [there's a TED talk](_URL_0_) that excellently sums up the biological reasons for why porn is bad for you. It's long (20 mins) but very informative and definitely worth the watch.\n\nThat being said it also causes an incongruence between expectations and reality. [u/Ultra-ChronicMonstah](_URL_1_) explains it well.\n\nedit: accidentally words",
"This is gold, but should we clarify that we're talking about video porn? Where is the line drawn? And when do we call it erotica instead?",
"Just warning you to be very catious of responses being biased due to the slow inwards push by /r/ShitRedditSays and /r/NoFap.",
"When asked to choose between a lifetime of porn and a lifetime of a loving, committed, healthy, monogamous relationship, I expect nearly everyone would choose the relationship. \n\nMany will say that you can absolutely have both. I would humbly disagree. \n\nI'm not trying to reduce the whole issue to this supposed dichotomy, but this question would simply be my cover letter to a long discussion on the subject. I'm unmarried and have been very happily porn-free for 2 1/2 years for the expectation of something much better. ",
"who says it's bad?",
"Who said it was bad for you, and why did you believe them?",
"There's nothing wrong with porn. It all comes down to the user, just like booze or drugs.\n\nI have a very healthy relationship and use porn, I've had enough experience to know that the \"actresses\" are acting (faking it). This isn't how real sex is or should be. It's a toy.\n\nAlso, I keep in mind that I'm a lucky guy that some girl actually thinks I'm cool and wants to touch me.\n\nPorn is like any other vice, some can hang, others can't.",
"It isn't. Some people say it is, but they're stupid.\n\n^(now I need to fill up some characters so that my comment doesn't get removed because that would be bad.)",
"So I'm a little late here, but here are two excellent videos that answer this question thoroughly and in a simple-to-understand manner.\n\n1) _URL_0_ \n\n2) _URL_1_",
"From a developmental point of view (thinking about a person going from being a child to being a parent), porn throws off your expectations of what sex is all about. Porn is not about birds and bees, or love, or relationships--it's about creative ways to do 'intimate' things that other people could enjoy watching. More importantly, it's about fulfilling fantasies--including some that are potentially pretty dangerous or messed-up to try doing with someone you really care about. But there's no accounting for where people's fantasies come from, is there?\n\nSo from a sociological point of view (thinking about a person as a member of society, without judging) porn isn't bad or good. It's just part of a culture of indulgence. If you want to be moral, 'indulge responsibly' and remember that there's more to sex than you see on the screen. Religious morality would say otherwise, of course, but that's another story.",
"My boyfriend told me one of the best parenting stories I ever heard. When his dad busted him watching porn at 15, he sat him down and said this:\n\"You shouldn't be looking at this stuff. It isn't wrong or dirty or immoral, and it's normal that you're interested in it. The problem is that you don't know what having sex is like yet and so you can't see how this differs so much from reality. It will give you incredibly skewed ideas about what women want, what YOU want, and how things are done. These movies are all about showing the most to a viewer to turn them on as quickly as possible and that bears no resemblance to what you'll do with women in a few years. It's not bad, but it's bad for you.\"\n",
"Because your first time (if you haven't done it already) will be a shock when the woman isn't screaming with pleasure. You'll think \"Oh god, I must be terrible at this\" . And alas, you very well might be, if you're basing your sex off of porn. Then it'll slowly eat away at you, day after day \"Why wasn't she begging me to C on her T's or something, this isn't right\" Then you'll realize....it was all pretend. A dream that you bought into without even understanding the full concept. \"Women don't always get off, multiple times, using only vaginal penetration?!?!\" No. No they don't. You'll sit alone, huddled in the corner, weeping for a world that used to be, but you've already been through the looking glass and have seen the gross reality of the situation...and there's no going back.",
"Porn will cause you to masturbate, you will take longer showers causing you to be late for work, your boss will be forced to terminate you for your tardiness and you'll be forced to move back in with your parents that don't have the premium speed Internet service and you will relegate yourself to being one of those guys that actually buys porn. Don't be one of those guys. ",
"Because you're five. ",
"while not ELI5 - ASAPscience explains pornography [here](_URL_0_)",
"Here's a TED talk getting into some of the dirt about pornography and how it CAN affect our psyche.\n\n[TED TALK](_URL_0_)\n",
"Porn is a lot like alcohol. Some people choose not to drink it (watch it) for one or many reasons, and it's fine. Other people choose to partake responsibly, and it's fine. And then you have alcoholics (porn addicts)--the people who just can't stop drinking (watching) to the point where they need it to get through their lives, but it starts damaging the aspects of their lives that *aren't* involved with alcohol (porn). People become alcoholics (porn addicts) for a variety of reasons; some of it is due to the fact that some people are just more prone to addiction than others, while some may be related to underestimating how much it can affect your life.\n\nMoral of the story: if you choose to watch porn (and you don't have to if you don't want to), be conscious of how it affects the rest of your life. If it starts creeping in on work/classes, hobbies, relationships of both platonic and romantic varieties, then it may need to go.",
"ITT - The longest chain of replies I've probably ever seen. ",
"It sets unreasonable expectations about the partner and sex.",
"Here is a list of video links that redditors have posted in response to this submission (deduplicated to the best of my ability):\n\n|Source Comment|Score|Video Link|\n|:-------|:-------|:-------|\n|[arr0whead](_URL_7_)|36|[The Great Porn Experiment: Gary Wilson at TEDxGlasgow](_URL_15_)|\n|[ManInTheMirage](_URL_13_)|4|[Things You Didn't Know About Porn - Part 1](_URL_8_)|\n|[ManInTheMirage](_URL_13_)|4|[The Science of Pornography Addiction SFW](_URL_6_)|\n|[audreyshake](_URL_9_)|4|[B. A. No. 182](_URL_10_)|\n|[audreyshake](_URL_9_)|4|[\"This must be how moms feel on the first day of kindergarten!!\"](_URL_1_)|\n|[kushmau5](_URL_16_)|3|[The Great Porn Experiment: Gary Wilson at TEDxGlasgow](_URL_4_)|\n|[deit9000](_URL_2_)|1|[The Great Porn Experiment: Gary Wilson at TEDxGlasgow](_URL_5_)|\n|[buyacanary](_URL_3_)|1|[99 Red Problems](_URL_0_)|\n\n* [VideoLinkBot FAQ](_URL_12_)\n* [Feedback](_URL_14_)\n* [Playlist of videos in this comment](_URL_11_)\n* [Playlist of videos in this comment](_URL_11_)",
"Explain like you're five? Well you're only five years old, you shouldn't be watching porn.",
"_URL_0_\n\nThe study of whether or not (or the degree to which) pornography is \"harmful\" to people that watch it is a field fraught with multiple difficulties.\n\nBut, to explain very simply, possible negative side effects of viewing porn can be summed up in the following list. This is a very simple collection of claims made by some studies that have been done, and is not intended to be exhaustive. Nor should this list be mistaken to be claiming that any, all, or some of these are likely, common, or even possible. These are just some of the most commonly claimed correlations.\n\n1) Inability to achieve sexual satisfaction through \"actual\" human sexual activities.\n\n2) It enhances the likelihood and/or the degree to which men view women as sexual objects.\n\n3) It enhances the likelihood and/or the degree to which the \"sexual aggressor\" views the \"sexual recipient\" as a sexual object (e.g. how the \"top\" might come to view the \"bottom\" in homosexual porn).\n\n4) Social stigma. In some cultures or within certain specific environments within the United States (like your job site, for instance), having it become publicly known that you view porn can lead to socially enforced discriminatory behavior. Like losing your job.\n\n5) Studies show a strong correlation between both the amount of porn viewed and the amount of time spent viewing porn, and a subsequent proclivity for viewers to experience an \"accelerating spiral of need for more deviant material\" to achieve the same level of satisfaction. Basically, you become desensitized to \"normal sexual depictions,\" and require more and more extreme examples of sex to reach organism. Maybe you were fine with watching a couple have sex originally, but after a few years, only watching triple amputees have anal sex with unwilling animal participants will barely make your dick flutter.\n\n6)Dick burn (or clit burn, for the porn enthusiast ladies out there).\n\n7) Incriminating search history in your browser, as well as an aptitude to visit disreputable websites such as Reddit. ;)\n\n8) Social skills may atrophy.\n\n9) Viewers may develop skewed concepts of sexuality and/or the nature of interpersonal relationships between them (the viewer) and their gender of sexual preference. Generally, men might act like assholes around women and not even have any idea why.\n\n10) Viewers may experience enhanced feelings of loneliness and depression.\n\n11) \"Porn fulfillment\" may act as a distraction, thus preventing a viewer from more constructively using their time.\n\n12) Body image issues. This is very common for women who view porn. Interestingly, (this is my hypothesis) a greater societal awareness of this issue is why you so often see such positive posts in threads like /r/gonewild for women who have posted pictures of themselves and who have \"less than ideal body types.\"\n\n13) And, much like the link at the top suggests, you can supposedly become addicted to porn.\n\nPersonally, to some degree, I've seen friends of mine exhibit every single issue I just listed.\n\nAre these problems created by pornography, or, because of the fucked up way our culture forces sex into the shadows, is this merely a manifestation of how our culture both creates porn as well as creates the audience for it? Is it personal or societal?\n\nAfter knowing some of the possible issues with viewing porn, I'd say two better questions to ask are:\n\n1) If you know about the possible dangers, what can you do to make sure you enjoy porn \"safely?\"\n\n2) Are there any benefits to watching porn?\n\nAgain on a personal note, I'd say yes to both of those. But the reasons why would require another, much longer post.",
"For me, watching porn so often, getting more extreme over time, and masturbating every day caused me to not be able to get hard when I got my first real girlfriend and first started having sex. However, now that I've been with her for awhile, we have sex all the time and it's fantastic. I never watch porn or fap because I don't need it. Once you get past the allure of porn, you see how fantastic real sex can be.\n\nSeriously, it's fucking great. Quit porn and find a girlfriend/boyfriend (if you can).",
"This [TedTalk](_URL_0_) does a good job of answering this question.",
"I'm a long time porn user. My hands are calloused, my Johnston is painfully chaffed, and the only keys on my keyboard that work, are the ones that don't stick. Having said that, I see no reason why porn is bad for you..."
]
}
|
[] |
[] |
[
[],
[
"http://makelovenotporn.com/myths/facial"
],
[
"http://www.reddit.com/r/AskReddit/"
],
[],
[],
[],
[],
[],
[],
[],
[],
[
"http://www.reddit.com/r/Infographics/comments/16tevo/the_effects_of_pornography_on_dopamine_levels_sfw/"
],
[],
[
"https://www.youtube.com/watch?v=wSF82AwSDiU",
"http://www.reddit.com/u/Ultra-ChronicMonstah"
],
[],
[],
[],
[],
[],
[],
[],
[
"http://www.youtube.com/watch?v=1Ya67aLaaCc",
"http://www.youtube.com/watch?v=aJLRTL7w5qA"
],
[],
[],
[],
[],
[],
[
"http://www.youtube.com/watch?v=1Ya67aLaaCc"
],
[
"http://www.youtube.com/watch?feature=player_embedded&v=wSF82AwSDiU"
],
[],
[],
[],
[
"http://www.youtube.com/watch?v=rporwPqpJcI",
"https://www.youtube.com/watch?v=eV0rZO3VXR4",
"http://reddit.com/comments/1956bs/_/c8l5j6x",
"http://reddit.com/comments/1956bs/_/c8l4zb7",
"http://www.youtube.com/watch?v=wSF82AwSDiU",
"http://www.youtube.com/watch?feature=player_embedded&amp;amp;amp;amp;v=wSF82AwSDiU",
"http://www.youtube.com/watch?v=1Ya67aLaaCc",
"http://reddit.com/comments/1956bs/_/c8l0bm4",
"http://www.youtube.com/watch?v=aJLRTL7w5qA",
"http://reddit.com/comments/1956bs/_/c8l2cuh",
"https://www.youtube.com/watch?v=9BFow_8Cr04",
"http://radd.it/comments/1956bs/_/c8l851p",
"http://www.reddit.com/r/VideoLinkBot/wiki/faq",
"http://reddit.com/comments/1956bs/_/c8l2hh8",
"http://www.reddit.com/r/VideoLinkBot/submit",
"https://www.youtube.com/watch?v=wSF82AwSDiU",
"http://reddit.com/comments/1956bs/_/c8l4qew"
],
[],
[
"http://en.wikipedia.org/wiki/Pornography_addiction"
],
[],
[
"http://www.youtube.com/watch?v=wSF82AwSDiU"
],
[]
] |
||
7csrxw
|
why does each major city on the us/mexico border have a similarly-sized city opposite the border from it?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7csrxw/eli5_why_does_each_major_city_on_the_usmexico/
|
{
"a_id": [
"dpsgli7",
"dpshogv"
],
"score": [
4,
12
],
"text": [
"Trade/money. People live where they can obtain necessities and gain employment. People on both sides benefit from business conducted on both sides, plain and simple, from companies to (mostly day) tourists.",
"Quite a few of those border cities predate the territory's annexation into the US and were founded back when it was all Spanish territory.\n\nYou also need to remember that, prior to the modern era, (back in the \"Wild West\") border enforcement wasn't all that strict.\n\nCities, especially in the desert, are generally built where there's a good source of water. if you use the river as the line for the border, it's natural for people to want to live on both sides of it."
]
}
|
[] |
[] |
[
[],
[]
] |
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