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3m7km9
what happens when your skin "adjusts" to a new shaver?
Yes, I'm 5 and have facial hair. I see such messages on almost every shaver, telling you to give it some time to "adjust" to a new shaver, encouraging you to stick to it for a few weeks etc. And I personally experienced such adjustments a few times. First times with different shavers do tend to come with more irritation than usual. So what's exactly going on? Is something about our skin changing and adapting, or is it just the nerves getting used to the new blade angles/textures, or something else entirely?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3m7km9/eli5_what_happens_when_your_skin_adjusts_to_a_new/
{ "a_id": [ "cvcs0r4" ], "score": [ 3 ], "text": [ "Truth is, it's probably just the amount of time it takes to smooth out the rough edges of the razor blades. Electric shavers blades are not as fine and sharp as manual because they use the energy to essentially chop hair off. Brand new shavers edges might be a little too sharp and after a month or so of shaving, those sharp edges smooth off. " ] }
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3ha33k
why does drinking water in the morning make me physically ill, whereas at night i feel like i could guzzle gallons?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3ha33k/eli5_why_does_drinking_water_in_the_morning_make/
{ "a_id": [ "cu5le7m" ], "score": [ 5 ], "text": [ "Try eating some food before hand. Some people experience pretty bad stomach aches when drinking water on an empty stomach. " ] }
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9dfv4f
; how do we make sounds louder?
For example, when I turn the volume up on my phone what actually is going on the make the sound louder?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/9dfv4f/eli5_how_do_we_make_sounds_louder/
{ "a_id": [ "e5hgxzl", "e5hyyp1" ], "score": [ 5, 3 ], "text": [ "A loudspeaker is just a vibrating membrane compressing air (making soundwaves). Its like your eardrum in reverse. \n\nTo make a sound louder, you need to [increase the amplitude of the vibration while keeping the frequency the same (for a simple sound)](_URL_0_) \n\nHow exactly this works physically depends on the loudspeaker, but by turning the volume up you just increase the amplitude of your speakers.", "* Most speakers work by applying a voltage to a coil of wire attached to a cone surrounded by a magnet.\n\n* The voltage causes the coil to create a magnetic field that reacts to the magnet and causes the attached cone to move. \n\n* If you change the voltage from positive to negative, the cone will move one direction. If you change it back from negative to positive, the cone will move the other way.\n\n* Changing the voltage back and forth from positive to negative back to positive is how we get the cone to vibrate, which produces sound.\n\n* The loudness of the sound depends on how much air the cone moves, which depends on how far the cone moves. \n\n* The higher the voltage, the farther the cone moves.\n\n* So turning up the volume on you phone increases the distance the little cone inside your phone moves and it does this by amplifying the voltage of the audio signal. \n\n* Amplifiers work by essentially multiplying the intensity of the signal. Let's say the original audio signal started at 0 volts, then swings up to 10 volts, then swings down to 0 volts then swings down to -10 volts. Once you send that signal into the amplifier you'll get an output signal that starts at 0 volts, swings up to 20 volts, then down to 0 volts, then down to -20 volts. \n\n* Here we say that the signal has a gain of 2 because as you can guess the amplifier multiplies the input signal by a factor of 2. \n\n* The technical explanation of how an amplifier takes a voltage and multiplies it is a bit beyond ELI5." ] }
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[ [ "https://s3mn.mnimgs.com/img/shared/userimages/mn_images/image/b2.PNG" ], [] ]
3y7eiq
so many classic christmas movies show orphanages as a thing, i haven't seen or heard of an orphanage in that sense my whole life. do we no longer have them? why not? what happened to the classic tv type orphanage?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3y7eiq/eli5_so_many_classic_christmas_movies_show/
{ "a_id": [ "cyb5m9b", "cyb690f", "cyb6c5w", "cyb6hj0", "cyb6m28", "cyb70nl", "cyb777m", "cyb7kix", "cyb7oly", "cyb7utz", "cyb8biz", "cyb8i5p", "cyb9523", "cyb97nd", "cyb97qb", "cyb9dg8", "cyb9s3p", "cyb9vov", "cyb9wif", "cybaetm", "cybaglq" ], "score": [ 189, 7, 15, 10, 17, 16, 19, 84, 24, 5, 25, 48, 5, 4, 51, 6, 4, 5, 3, 3, 2 ], "text": [ "They aren't really a thing any more in the United states, I believe this happened after ww2, However I could be wrong about that.\n\n They've mostly been replaced with group homes/boarding school type environments. Also fostering is fairly big too.", "From my understanding the United states does not have enough orphans for an orphanage system to make sense. Which is why we have a foster care system instead. In countries with large orphan populations you will likely find orphanages more in line with what you see in old films.", "After many stories of abuse and death, especially in religious orphanages, people demanded they be shut down. Magdalene laundries and Georgia Tann are two good examples.\nAs for the dog shelter comment, that was almost how it worked with the private work houses of London, since those children had no legal standing.", "Originally orphanages were just a temporary place for children until a foster family could be set up. Having lived in a foster home myself growing up, the entire foster care network is pretty established now. Also where I grew up Group Homes were for juvenile delinquents (lived there too for a while).", "There's one down the street from where I am right now. Definitely still exist in US. Probably more common in the south, as churches still provide a large number of social services, such as orphanages, there. ", "Orphanages are still very much a thing in other countries/continents ; Africa, Russia, Phillipines etc. Here and now, we have foster care plus social assistance that helps many parents who otherwise couldn't keep their child. Orphanages mostly exist and are needed where war or poverty create that need. As for how orphans are picked, I don't know first hand, but if celebrities adopting overseas are any indication, yes, it does pretty well work like that.", "Have several friends who were raised in the last of the orphanage system in the US. According to them there weren't enough workers to provide proper oversight, lots of abuse, and frequent male-male rape among the kids.\n", "Follow up question for knowledgable people: is it a good thing they disappeared?", "As many people here have said, group homes replaced orphanage in the U.S. in the early 70's. Exposes such as Geraldo Rivera's of the Willowbrook State School on Staten Island, talked about in the terrifying documentary Cropsey [\"Cropsey\"] (_URL_0_), helped bring warehousing people to an end.", "We have a nice one in Abilene, Texas. Has a very good reputation. _URL_0_", "There still are orphanages. They're called children's homes. Many kids live with foster parents but here in my town there is still a place where parentless kids live.", "They're called \"Group Homes\" now because we like to sanitize our language to makes ourselves feel better about our society.\n\nAlso, in general, there are fewer mustachioed vallains and musical numbers in group homes.", "Because lots of abuse happened, for example:\n\n_URL_0_\n\nOrphanages were religion-based, and there was a lot of rape and abuse.\n\nModern orphanages are now called foster homes.", "Yeah, they are still a thing, but not to the extent you see in old movies. I went to a private school in Mt Dora, FL that was also an orphanage. There were about 30 kids that lived in the various houses on campus with the home parents. Some were occasionally adopted and left but must finished school there and went on their way. I think it has a good reputation.", "Sounds like everyone is just talking about America. I've been to an orphanage in Haiti they are very sad. Kids had shoes which the sole was completely gone. Along with terrible places to stay, lack of schooling, food, and many other things. The kids were so happy though we donated lots of shoes and cloths but the kids from when we got there where just some of the happiest kids we had ever met.", "I grew up in a boarding home/school and it wasn't bad... though I didn't really know what the other side of things were until I was 13... and still family's and certain \"normal interactions\" kinda really weird me out.\n\nEDIT: come to think of it now, some of those experiences were absolute shit as were most of the people. ", "I work in a group home in the US which is comparable to an orphanage, except instead of orphans, most of the kids I work with were taken from abusive families and are now up for adoption.\n\nPlease consider adopting. There are kids out there waiting.", "There was a pretty dramatic decline in kids being sent to orphanages after abortions were legalized.", "There is one about 2 miles from my house in NC. That said, they are pretty rare. What happened? Abortion, birth control, tremendous improvements in adult workplace safety and health generally. And then we really shifted to other systems, like foster care.", "I grew up near a pretty large orphanage in Enterprise Florida. Two full schoolbuses went to my junior high. I had a good friend lived there. My mom would go and pick him up and take him on trips with us. He was from Columbia and his mom got deported. She had a record so they (the state) took him and stuck him there. He vanished soon as he turned 18.", "The classic TV orphanage like the one in Oliver Twist (not like Cider House Rules) were institutions originally founded by religious organizations or religious backed individuals and were created to get kids off the streets. There was a period in Europe where war was waged pretty heavily and for a long period of time which left a great deal many children left homeless and orphaned and pretty much on their own on the streets to beg and fend for themselves. They had no access to school or job training so their futures were pretty bleak. \n \nWhat people originally intended was for religious minded people to create group residences for the kids where they would be fed and sheltered and taught religious beliefs ***and*** a *trade*. \n \nPeople soon realized that orphans could be exploited to be a cheap form of labor (child labor) and put them to work, often to exhaustion, with low food, little rest, and dire consequences should they not fulfill their now *indebitedness*.to their carers. \n \nI don't think it got as bad in the US as it was in Europe and Britain back Charles Dickens' day, but it did occur here too. \n \nThat lead to sweat shops which lead to child labor and exploitation laws which lead to a decline in work based orphanages which were largely self supporting. The orphanages left were like the ones in Cider House Rules which were funded by religious donations or state funding. Both of those began to dry up while at the same time fewere children were orphaned from wars and such so the state switched over to what we have now, which are group homes, I think. \n \nThis is how they are referred to in modern films: \n_URL_0_" ] }
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[ [], [], [], [], [], [], [], [], [ "http://www.imdb.com/title/tt1277936/?ref_=fn_al_tt_1" ], [ "http://www.hendrickhome.org/hhc/" ], [], [], [ "https://en.m.wikipedia.org/wiki/Duplessis_Orphans" ], [], [], [], [], [], [], [], [ "http://youtu.be/bfqYdon7hSw" ] ]
22iwiz
how does the check engine light on cars know to come on? does it only cover certain problems ? how does it work?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/22iwiz/eli5_how_does_the_check_engine_light_on_cars_know/
{ "a_id": [ "cgn8exr", "cgnazvj", "cgnbzkr", "cgnclep", "cgncwj7", "cgndu02", "cgneyuu", "cgnfa9s", "cgni8c0", "cgnmwv9", "cgnmxql", "cgnnmqn", "cgnnvdl" ], "score": [ 346, 33, 2, 10, 2, 6, 2, 2, 9, 4, 3, 2, 2 ], "text": [ "You car has a computer that is connected to many sensors throughout the vehicle. Most drivers don't need to know what is actually wrong with the engine (indeed, most don't even care), so it's far easier to have a single \"Get someone to check this out!\" light than to provide a detailed explanation. A mechanic can connect to the computer to find out what is actually wrong with the car, usually through a specific code that might indicate which sensor says something is wrong.", "Cars made after 1996 have an OBD-II system (On-board Diagnostics). This diagnostic system has \"Readiness Monitors\" that are coded to monitor certain aspects of emissions primarily.\n\nWhen you disconnect the battery (or reset the monitors via a tool), they return to a not ready (Incomplete/Inconclusive) status until the various checks are executed programatically. As the checks are executed by the computer, the readiness monitors will either show \"OK\", \"N/A\" or \"Error\" (IIRC).\n\nA monitor that is in error will have a specific trouble code that is generated such as P0420. This code won't tell us much other than it's related to the \"Catalytic\" Readiness Monitor and there is a problem somewhere \"near\" the catalytic converter part of the exhaust system.\n\nEach readiness monitor has many, many trouble codes that go with it and some will throw others. So you may get one error code but that code won't tell you exactly what the problem IS, it will only tell you the problem is in that *part* of the system. For the Catalytic monitor, there are O2 sensors before and after the catalytic converter and they could be malfunctioning or it could be the catalytic converter itself, or it could be a combination.\n\nWhen you have a Check Engine light (CEL) or a Service Engine Soon light, your car will not pass emissions for those states & counties that require yearly emissions testing until the reason for the CEL / SEL has been resolved.\n\nSometimes you can get trouble codes as \"one offs\" - for example, if you tighten your gas cap too much / too little it will often cause a check engine light because there is a monitor for pressures (oxygen levels?) in the fuel system. This code will clear on its own after you fix the gas cap and drive normally for a few days.\n\nSo, if you've gotten gas recently and the engine light came on, it may be that you didn't get the gas cap tight, or too tight **OR** you overfilled the gas tank. **ALWAYS** stop filling your tank when the pump clicks the first time. Don't force gas into the gas tank.", "The day your warranty expires the engine light comes on for the remaining life of the vehicle.", "Someone mentioned that there's sensors but maybe I can expound on that. Your car has mad sensors bro. Like hundreds. There knock sensors to detect detonation from shitty gas. There's a cam sensor and crank sensor to make sure they're spinning at the rate they're supposed to. there's a sensor in the oil pan to tell you when the oil is low. There's a sensor around your intake(MAF) to tell the computer how much air the engine is getting, along with what temperature the air is. Then there's O2 sensors on the way out so the car knows how much the fuel/air ratio is coming out of the motor. basically if one of these sensors gets a reading that's outside the norm that was programmed into it, the sensor tell the computer that something's wrong. Like if your MAF(Mass Air Flow) sensor has a little broken coil, it will tell the computer that your motor isn't taking in any air at all. Well if you're cruising down the highway at 70 mph that reading is most likely false. So your car will go \"Hmmmm my MAF is telling me the engine isn't getting any air, but if it's still running ok then most likely it IS getting air, it's just my readings are off...probably the MAF is broken!\" then it throws a code saying \"Uh...somethin' somethin' MAF bro fix it.\" then your mechanic does best he can and charges you a bunch of money. ...the end.", "It's important to note that the systems were first put into service as part of pollution control. Last I checked those are the only codes required by law. Other codes have been added but mostly by car companies to monitor whatever they choose which is why you have to obtain brand specific codes to read certain warnings. Usually this means that a check engine light does not mean you have serious engine problems and when you do, usually the computer will enter \"limp home mode\" which causes the fuel to go rich to prevent overheating the combustion chambers. It allows you to continue to drive the car although it is not recommended. Of course there is usually an associated poor performance and horrible gas mileage as a result.\n\nThat said, there are warnings that indicate a problem that might become catastrophic later, so don't blame me if your car dies. ", "It's either an O2 sensor or someone didn't tighten the gas cap all the way... ALWAYS!!!!", "The true question is: What happens when the Check Engine light is broken", "A car these days is a computerized mechanical vehicle. So think of it as your computer. If your computer has a problem it that is noticeable without causing a catastrophic failure then it will alert you. Your car can do the same thing. The light will come on if a sensor is bad or maybe you forgot to tighten you gas cap. \n\nNow if it's on and flashing you have a much larger problem. That typically signifies a bigger problem in which you need to pull over and shut your car off. Wait a minute or two and try to start it up again. Most likely even if the light is no longer on you can drive it to your dealer. They will be able to plug into your car and tell you what happened. Every car is different and you should always consult your manual but this is a good general guide.\n\nIt knows to turn on when an electrical current which was sent by the computer tells it to.\n\nIt will not cover every problem. It will only cover the problems that can or are electronically monitored with a sensor.\n\nI could have formatted this a bit better but hopefully this helps you out.", "I'm going to expand on the responses given and follow up on some of the advice I'm reading in the comments, as I find some of it misleading. Preface: I'm a college-educated, Chrysler-trained former dealership technician. Communications systems and electrical faults on modern vehicles are *complicated*. Always consult a professional repair shop in regards to any dash lights if you care about your car.\n\nPicture a room like [this](_URL_0_). Instead of papers, every one of those guys is looking down at a control board in front of him covered in lights. Every light is something on the car being watched with an expected parameter. If it's within expectations, it's green. If it's not, it's red. Every one of these guys is watching his lights and giving a continuous thumbs up to the head honcho to let him know they're all good on his end. If any worker's light turns red, he gives a thumbs down and the head guy hits the \"problem found\" button, turning on your MIL - Malfunction Indicator Lamp, the preferred term nowadays since not every problem is engine-related. That's literally all the information you get without further diagnostics.\n\nThis is where it gets complicated: If a sensor is reading data that signifies something is wrong, it switches that green light to red and the alert process begins. That's its job - but if that same sensor dies, it stops sending data at all and the light turns red and the same process happens. If the power supply gets interrupted and the sensor can't give you the data, the light turns red, etc. There are a hundred reason for that light to turn red. So when you get a thumbs down, what happened? You can't tell by just reading the code. If it were that easy, those $20 code readers would put repair shops out of business; the expertise you pay for at an automotive repair shop is their ability to interpret that code and correctly follow up on the problem to see what's actually wrong. Trouble codes **are not** self-diagnosing. They're signposts to help professionals get their bearings and head in the right direction. They're cries for help from the vehicle's various computer systems - like a kid telling you where it hurts, but not much else.\n\nThe problems covered by the MIL depends on the age of the vehicle. Older vehicles only monitored basic things that were mandated, like emissions or imminent engine failure. Newer vehicles monitor nearly everything on the car. It's also worth noting that some problems may be detected but aren't an immediate safety concern to the driver, and so don't turn on the light at all. The MIL only turns on when A) the reliability of the car to start and get somewhere without failure is compromised or B) your car is putting out emissions beyond what the government said was okay. If a blend door in your HVAC isn't responding as expected and your heat is therefore not as hot as you're asking it to be, there's likely a code set for that as well - but it won't panic you by turning the MIL on.\n\nIt may not be directly monitored, but if something goes wrong, some sensor will see it. As an example, if your engine block gets a crack in it, that's a huge deal and will turn on your MIL, but it isn't like there's some sensor that's literally inspecting your engine for cracks. A cracked block will have symptoms, and those symptoms will be picked up by the sensors monitoring misfires, fuel efficiency, expected power output, engine knock, emissions controls, etc. It's the professional's job to interpret the code(s) and perform the appropriate diagnostics to deduce a cracked block is causing it.\n\nThe actual operation of the sensor's communication is just numbers. Every sensor is built to monitor something like pressure, temperature, RPM, something with a numerical value. It's engineered to interpret those factors and translate them into a voltage. So if there's a temperature of a fluid being monitored for a safe range between 60 and 160 degrees, and the sensor's construction says 60 degrees = 1 volt and 160 degrees = 4 volts, and the sensor is putting out < 1 volt or > 4 volts, the computer reads that as the fluid being too cold or too hot and sets a problem state, turning on the light. The numbers change, the variable being monitored changes, but every sensor is just putting out a corresponding voltage and the computer looking at the sensor starts to scream if it sees a voltage it doesn't like.\n\nRe: the advice given on going to Autozone, Advanced Auto Parts, or other parts retailers for free code diagnostics:\n\nTheir diagnostics involve connecting a device to retrieve the code, then printing out an automated slip of paper that lists statistics. It lists the top 3 or 5 most commonly reported repairs associated with that code. It has no idea what's wrong with your car. It's saying, \"a hundred people had this code and 78 did X and it went away, so give that a shot.\" I **severely** don't like this approach and wish parts retailers wouldn't offer the service at all if they're going to give such lazy, ambiguous information. I suspect they do this as easy leverage to sell you parts. Consumers come to you because they have minimal knowledge about their cars, and if they look to you as the expert, your half-hearted information is taken as gospel. I've had some poor customers look at the #1 result on their sheets of statistics and get it locked in their heads that that's what's wrong with their cars, no matter what, because that's what the expert man at Autozone told them. Thousands of dollars later, they bite the bullet for a dealership's labor rate and find it was something silly like a broken wire. *If it isn't from the mouth of a paid professional who respects his labor and expertise enough to charge you for it, take it with a grain of salt.*", "In California and Hawaii it is illegal for auto parts stores to read OBD codes.", "mine was on for 4 years and still is", "Here's a little story that explains why it is important to fix every problem and not let them linger, no matter what. \n\nA friend and I bought cars around the same time. Both had check engine lights on, both for oxygen sensors. \n\nHe checked out the price for repair, $700 (our currency, a week's pay plus change). Mine was to be about the same. I couldn't afford it, he chose not to. \n\nOver the next couple of years, something else went wrong in his, I forget what, and because of the check engine light being on, he never found out until it was too late. The repairs apparently would have been a few hundred, but ended up being close to $2000.\n\nOn hearing that, I went and got mine done now that I could afford it. Two weeks later, I was back in the shop angry that the light was back on. It was a different issue, but related. Since I hadn't changed the oxygen sensors, the car had been running lean with too much oxygen, causing it to work harder or something to get the same power. It was a cheap fix of the fuel pump, but if the check engine light had still been on, I wouldn't have known about it. \n\nI really don't know too much about it, that is not my field at all. All I know is that I really should have fixed it right away, and was lucky I didn't get other, bigger problems. That light is there as a warning. Do something about it.", "Easy. They set it for one day after the warranty expires." ] }
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[ [], [], [], [], [], [], [], [], [ "http://www.faqs.org/espionage/images/eeis_02_img0698.jpg" ], [], [], [], [] ]
606pwx
what happens to a persons shares when they die?
Say for example I owned majority shares in a company that we'll name Company A. If I have no will or document that states what happens to my shares, what would then happen to them?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/606pwx/eli5_what_happens_to_a_persons_shares_when_they/
{ "a_id": [ "df3w3i7", "df3wl6a" ], "score": [ 2, 3 ], "text": [ "Depending upon the laws of the state.... They would either be remitted back to the Company, or to next of kin. \n\n_URL_0_", "Let's use an actual example. \n\nWhen my grandfather died, he did not have a will, and I was the executor of the estate. He had stock in a company, and the company had been offered to buy their stock back at 10% over face value. They turned down the option, and I sold the stock to pay off some debt from the estate. " ] }
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[ [ "https://www.quora.com/What-happens-to-the-shares-when-a-shareholder-dies" ], [] ]
2hqwn5
the political turmoil in hong kong. what caused it, why it's such a big problem.
It seems to be getting worse
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2hqwn5/eli5_the_political_turmoil_in_hong_kong_what/
{ "a_id": [ "ckv7k0f", "ckv8b8k", "ckv8zlx", "ckv98dc", "ckveni8", "ckvew9j", "ckvf6mf", "ckvh26h", "ckvhl57", "ckvjnvl", "ckx0gay", "ckxcwdc", "cky8u7f" ], "score": [ 156, 9, 8, 113, 2, 2, 19, 2, 2, 2, 2, 2, 2 ], "text": [ "Hong Kong was a British colony, but was later given to China in 1997. In being given back, they made an agreement that Hong Kong would function mostly independently, but follow certain rules. Note that because of its history, Hong Kong people generally do not consider themselves \"the same\" as mainland China: they have different culture, people, language, and government.\n\nFlash forward to 2014, China proposed that Hong Kong could have a democratic election system to vote for their leader beginning in 2017, but only if the candidates were supported by the Chinese government. Hong Kong residents (mostly students) protested, which has progressively gotten worse. They're angered that China has restricted growth of democracy, and they desire a continued true democracy, not a masked communist system.\n\nEdit: I realize I didn't answer the second part of your question. Why's it a big problem?\n\nIt's a problem for Hong Kong people who desire democracy. It is a problem if you are the Chinese government trying to handle part of its country. It is a problem if you are an advocate of freedom and democracy.\n\nIn terms of global problems, I highly doubt the situation is so bad that it will disrupt how Hong Kong operates (most of the protesters are students, and they highly advocate peaceful protest). The protest site is in the heart of the financial sector, and Hong Kong is one of the world's biggest financial/business hubs, but the protest will not likely damage the economy in any way. This is not Liberia or Syria; it will not escalate to violence.\n\nEdit 2: For clarity: the protest site is in the financial district. That does not mean that it is large enough to disrupt the financial sector. Think Occupy Wall Street: their protest did not cause all of Wall Street to shut down, despite their location. \n\nEdit 3: Changed \"Hong Kong was originally a British colony\" to \"Hong Kong was a British colony\" for clarity.\n\nEdit 4: Thanks for the gold, kind internet stranger :)", "Lots of good answers, I have posted the below comment before, hopefully it is useful here:\n.\n.\n\nBackground: HK was a colony of the UK, in 1997 HK was \"returned\" to China. It was clearly said at the time that the HK Government will be separate from China's for 50 years. Since 1997, from HKs perspective, China has been pushing and even crossing the line numerous times, more so in recent years.\n.\n.\n\nWhat's the problem ?\n\n*HK citizens are only allowed to vote for candidates who are chosen by China government . Hence it's not exactly a democracy.*\n.\n\n.\n\nWhy Is HK protesting ?\n\n*We don't want a government that will pass legislation that benefits China at the cost of ruining Hong Kong, without even a chance to officially say \"no\". Our cultures are too different between HK and China and therefore the accelerated transition to merge the cultures is obviously not working.*\n.\n.\n\n\nWhat's the point ? What does the HK people want ? Other countries ain't gonna cut ties/go to war with China. \n\n*We just want transparency and proper democracy in the next 2017 elections. Every government has some dirt, but to go this far to avoid a democratic election, it gives the impression there is a strong motive to manipulate our legislative process to THEIR BENEFIT. When you know your government is acting for the benefit of ANOTHER economy, you would be unhappy too, yes ?*\n.\n.\n\nFeel free to add anything I missed, there are plenty of comments with great insight in this post . Please forgive the formatting as I am on mobile .\n\n\n", "in the sino british joint declaration signed in 1984 it was agreed that after the expiration of the 99year lease the new territories would be handed back to HKG but given the proximity of HK island (which was not originally part of this lease) to Kowloon and the new territories and problems arising from its defence HK island was also included as part of the handover package. \n\nseveral stipulations of the stipulations of the agreement are in play here :\n1) The HKSAR will be directly under the authority of the Central People’s Government of the PRC and will enjoy a high degree of autonomy, except in foreign and defence affairs.\n2) It will be vested with executive, legislative and independent judicial power (including that of final adjudication) and the laws currently in force in Hong Kong will remain basically unchanged.\n\nthese stipulations eventually became enshrined in what we call the basic law ie a constitution of sorts. article 5 of the basic law states that \"The socialist system and policies shall not be practised in the Hong Kong Special Administrative Region, and the previous capitalist system and way of life shall remain unchanged for 50 years\". this was to be the basis also for the 'one country two systems' policy that deng Xiao ping established for special administrative regions (SARs) such as macau and hong kong. that these countries would remain as separate entities from mainland china but they would still be governed by the CCP (it sounds much more complicated than it actually is). \n\nthe main crux of the argument that the protests have today is enshrined in article 45 of the basic law which states \"The Chief Executive of the Hong Kong Special Administrative Region shall be selected by election or through consultations held locally and be appointed by the Central People's Government. \n\n The method for selecting the Chief Executive shall be specified in the light of the actual situation in the Hong Kong Special Administrative Region and in accordance with the principle of gradual and orderly progress. The ultimate aim is the selection of the Chief Executive by universal suffrage upon nomination by a broadly representative nominating committee in accordance with democratic procedures\" \n\nup till now the CCP has prevaricated in saying that the chief executive must be vetted and approved by them to prevent disorder. in 2007 the National People's Congress Standing Committee stated the aim was to given HK universal suffrage in a decade ie 2017 but on the 31st August 2014 the NPCSC somewhat reversed their 2007 position by stating that the Chief Executive of Hong Kong must be a person who loves the country (china) and loves hong kong and to ensure that the person does so they must still have the power to vet candidates for the CE position. understandably people became outraged over this change. \n\nin early 2013 a fellow called benny tai proposed a non violent civil disobedience movement based on the occupy x movements across the world at that time, unsurprisingly he would call his movement 'occupy central with love and peace (OCLP for short but often shortened to occupy central) . this movement in hk was to put pressure on our legislative council to only stand for real democracy and real universal suffrage. as 2013 came and went and morphed into 2014 it became increasingly clear that universal suffrage was not to be. \n\nscholarism is an activist group comprised of current students that as established in 2011 when the CCP attempted to foist education reforms on HK that would entail lessons regarding the china. they have also taken an interest in the universal suffrage debate siding with those who want democracy. \n\nI forget exactly what happened over the weekend but scholarism went and 'occupied' a public space just outside the government offices, the police removed them. benny tai seeing that scholarism had just stolen his thunder hastily announced the start of occupy central at 0140 on Saturday morning and this is where we are now. ", "Some History on Hong Kong which may make understanding the current conflicts easier: HK isn't governed the same as Mainland China. HK is a 'special administrative region' of the PRC (People's Republic of China). Hong Kong was colonized by the British in the 1800's. In 1997 Britain handed HK back to the Mainland. But everyone in HK was like 'Whoa, we have a developed society here, the mainland is very much still developing, we should keep things separate until Beijing and the rest of China catches up\" and so they said, \"OK, HK's **judicial** and **political** systems will be governed by the Hong Kong People for 50 years (Until 2047) so we can transition slowly. HK will use the same currency as before (HK$), and their citizens will continue to carry HK passports. Beijing will protect their borders, etc. \nNaturally, Hongkongers have some mistrust for how Beijing will honor this 50 year handover plan. You see, Mainland China (PRC) is governed by an autocratic government (a single party), the Chinese Communist Party. They do whatever they want in China. Sometime's it's in the best interest of the people, sometimes it isn't. The idea of this group gaining control of HK scares the shit out of Hongkongers. \nThey were told they would politically govern themselves for 50 years! It hasn't even been 20 years and they are seeing the autonomy of the political system already compromised. Right now, students are protesting due to Beijing recently declaring only 'pre-approved' candidates are eligible for Hong Kong's next election. They are basically getting loud, and protesting to show they will fight to maintain the freedoms they still have. ", "TIL Hong Kong and another city by the name of Macau are referred to as a Special Administrative Regions.. SAR's.. \n\n_URL_0_ ", "Because when the British gave Hong Kong back to China in 1997, they were promised a democratic rule, in accordance to what the citizens of Hong Kong had known. Hong Kong was going to be governed under the \"One country, two systems\" rule. This also applies to Macau and is what China has been proposing to Taiwan.\n\nHong Kong is special and as a \"mainland-Chinese\" citizen, one even has to get approval to visit Hong Kong because of the freedoms it enjoys over mainland China. I don't know if this is the same with Macau but I could imagine. Things like the Great Firewall don't exist in Hong Kong and is perceived as dangerous by the Communist Party.\n\nNow, the Communist party wants to approve who can run for elections in 2017. This is contrary to the semi-democratic state of Hong Kong. You were supposed to be able to run for elections as in any other democratic nation. No government approval needed. Yet the Communist party is trying to tighten it's grip on Hong Kong.\n\nThe protesters are angered mainly by this. This is also seen as a step in clamping down totally on Hong Kong. They are afraid that Hong Kong will eventually lose all of their priveleges/freedoms and end up just like the rest of China.\n\nBasically, most people are thinking, \"if we let them get away with this, then what's next\"? ", "Think it like this. You have a divorced parent. Your Dad is rather wealthy progressive and lets you do what you think its best but still gives advice on what to do. Your mom on the other hand is a broke, racist, backwards, control freak and will not give you one bit of freedom whatsoever. But when your parents were divorced the court said you need to live with your mom after \"x\" amount of years and dad agrees to it. When the time comes for you to live with your mom you're scared shitless because you know she's a crazy bitch chicken and refuse to leave. In order to make you come live with her for child support $$ she says you get to do everything you got to do in you dad's house. After a few years mom starts to break that promise and you are scared and start arguing with mom. This Is a big problem because mom needs you for your child support $$ you bring in but at the same time she knows if she lets you do what ever all her other adopted children lets name them tibet and xinjiang will also want to do whatever and mommy dont want to look weak does she?", "Can anyone ELI5: What do they hope to accomplish if they do gain true democracy? Would it be complete independance from China or would it still be like it was when it was first handed over? What would be a viable reason for HK to stay with China? And would HK be able to manage itself on its own? ", "One issue not mentioned here is that many Chinese people think the HK protesters need to STFU. I live in China and I've talked to lots of people about this (of course only toeing the party line that I read from the China Daily) and they feel like HKers think they're better than mainlanders. Many of my friends are still upset about the whole Opium Wars that gave HK to England and think that if this was any other country in the world there wouldn't be any international interest. People are just focusing on it to bash on China some more.\n\nI'm not saying I agree with them, but that's a local mentality if you're interested. The CCP is good at painting China as the victim.", "Human beings want freedom. China controls Hong Kong.. Residents of Hong Kong are considered humans.", "Are Hong Kong & Macau Countries?: _URL_0_\n\nCGP Greg short and simple explanation", "As a teenager living in Hong Kong with a non-mainstream perspective on this protest. I personally think that this protest is both meaningless and irritating. I do appreciate these teenagers fighting for what they believe in and how they are doing this out of the passion to improve Hong Kong, but this protest will get nothing changed due to the fact that the mainland Chinese doesn't care, why would any government care about teenagers protesting on the streets.\nThe teenagers to me are warriors, fighting for Hong Kong's true independence. The problem is that the protests are affecting other people living in Hong Kong's life. Since the protesters have already taken over major traffic routes and other major commercial areas, people had to take a longer paths to their workplaces. Another problem with people hoarding in one area is that medical emergencies cannot be ceased swiftly due to the fact that roads are occupied by these people, usual time of an ambulance reaching one point is 15-20 mins, after the incident it took more than 40 mins. \nAfter the protests happened, posts supporting the protests had been flooding my Facebook wall, from pictures of people wearing the symbolic yellow ribbons to videos showing how the police were \"criticizing\" the citizens. There is always the mainstream side of a story, but nobody ever sees how the police are being made fun of by people abusing their rights, how the police are constantly being stabbed with broken umbrellas while they were passively enforcing the metal fences protecting government designated restricted areas, police officers taking hits on the head by heavy objects from people on top of bridges.\nAlthough I do not fully support the police department's use of tear gas and military grade pepper sprays in early stages of the protests, but every conflict has a fuse lighter.", "Dont downvote me just because you disagree with my arguement.\n\nSee, my dad used to be in the communist party and is very familiar with their politics. He said that the current prime minister has been putting a lot of corrupt politicians into jail and out of work. \n\nHe said that this recent uprising by the hong kong citizens have been puppeteered by these ex-politicians. His reason is that Hong Kong poltics has always been tampered by china ever since it was handed back by the british. It is only now that they're revolting because of these ex-politicians who have their fingers rooted deep into group leaders and media groups.\n\nBasically, the whole thing is corrupt. You have the victims of hong kong being used by corrupt officials to reinstate their power by bringing down the prime minister, and you have the prime minister trying to 'again' influence the politics on Hong Kong." ] }
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[ [], [], [], [], [ "http://en.m.wikipedia.org/wiki/Special_Administrative_Region" ], [], [], [], [], [], [ "http://youtu.be/piEayQ0T-qA" ], [], [] ]
aas76i
is there an up and down in outer space?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/aas76i/eli5_is_there_an_up_and_down_in_outer_space/
{ "a_id": [ "ecujo86", "ecwb9an" ], "score": [ 13, 2 ], "text": [ "The sense of orientation is due to gravity. In the vacuum of space, \"up\" can become relative to what you make it. That being said, that relativity can cause all sorts of confusion if you don't establish a baseline in yourself.\n\nIf you ever read the book Ender's Game (it is a movie but this concept is explained in beyond adequte detail in the book), one of the greatest successes of Ender's 'toon is establishing that baseline.\n\nHe goes to train his 'toon in the battle room, and with it being weightless, they discover that giving orders, and maneuvering is difficult because they immediately loose their orientation. Due to this, Ender tells them that the \"enemy's gate is down.\" There is a larger metaphorical meaning to this.. however, for your question, Ender created a baseline for his 'toon, which allowed them to orient themselves, and have a direction to face, and move, in order to create effective strategies.\n\nTL;DR\nWithout gravity, orienting yourself is very difficult. By giving yourself a baseline (such as saying Earth is down, or moon is up), you can possibly help to alleviate that issue.", "\"The enemy gate is down.\" - Ender's Game\n\nWith no gravity to orient you, relative directions (up, down, left, right) are totally meaningless and from a practical standpoint, can be assigned relative to any arbitrary object or direction." ] }
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4o9pzl
what is happening in an automatic transmission that prevents a stall when stopped in gear?
I know a manual car needs to either be in neutral or the clutch disengaged to prevent a stall when stopped but what is happening in an automatic transmission.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4o9pzl/eli5_what_is_happening_in_an_automatic/
{ "a_id": [ "d4ar2pf" ], "score": [ 3 ], "text": [ "Automatic transmissions have a part called the torque converter in addition to an automatic clutch.\n\nThe torque converter consists of two impellers in line in an oil-filled casing where one impeller is connected to the engine and gearbox and the other to the drivetrain. When the engine turns one impeller, it transfers the rotation through the oil to the other impeller.\n\nThis is a soft coupling, so when the drivetrain is blocked (e.g. because you're holding the brake), there is no immediate damage." ] }
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7v8vr7
why does a pc have to be significantly more powerful than the console it tries to emulate?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/7v8vr7/eli5_why_does_a_pc_have_to_be_significantly_more/
{ "a_id": [ "dtqddlr", "dtqdhdb", "dtqfnrx", "dtqlo9k", "dtqnanp", "dtqq4dn", "dtqrop5", "dtqsscv", "dtqte1d", "dtqtksz", "dtqukm2", "dtqutff", "dtqv1bi", "dtr64sa", "dtrb84k", "dtrbfi0", "dtrbrd0", "dtrc4pc", "dtrf8c1", "dtrghsa", "dtrwsxy" ], "score": [ 950, 7, 595, 4883, 82, 3, 7, 5, 2, 15, 2, 5, 3, 2, 5, 3, 2, 3, 1765, 5, 2 ], "text": [ "Because a PC is not built to understand commands from different consoles.\n\nConsoles have their own hardware architecture, and their own hardware commands. Consoles have been designed to streamline and run these commands as efficiently as possible.\n\nPC's however, run on a different hardware architecture. As a result, the emulator has to convert all these hardware commands into software instructions the processor can understand and run. With software overhead as well as the multiple instruction conversions that happen per second, it's clear that an emulator must be more powerful than the console it emulates", "Because the console has separate specific hardware for doing every element of the process. A main CPU, hardware for generating sound, video circuitry, etc etc, on which runs the main kernel which the game talks to. \n\nAn emulator is purely software. In order for the original game software (a rom) to work properly with this software, it has to absolutely mimic the behaviour of the original system. So you have to simulate the CPU, simulate all the ancillary hardware, as well as the internal software. \n\nBecause there's all that extra stuff to do, you need a more powerful computer. ", "EDITED: So, my original response got zapped by the mod (and I've no interest in debating the merits of that, let's move on), so let's try again.\n\nTo emulate means to equal or approach equality with. What makes console emulation hard is that your PC has to do it well enough to be acceptable (the game must look the same, say) and fast enough to play the same.\n\nImagine your friend drew a picture with some colored pencils. Looks great right? Now your job is to take another sheet of paper, and, as quickly as you can, draw exactly the same picture. Same lines, same shades, same colors. Your pencils are mostly the same, so that at least gives you a leg up, but boy...it's gonna be hard isn't it? Now try doing that and being told you have to draw it as fast as your friend did the first time.\n\nLet's take a detour into the \"mostly the same\" clause. If the PC has key components that are identical to the console, that's like you have the same colored pencils. You say \"I need a thick dark orange \" and lo and behold, you have the perfect pencil to hand. This is like your PC running the same operating system on the same processor chip as the console. Life is looking sweet. But if the components differ, that's like you needing a thick dark orange but only having a thin pencil. You can get there, but it's gonna take more time. In PC terms this is like having a CPU that has different chip registers from your console. Or maybe you need orange but you only have red and a yellow. Your PC is missing some hardware feature of the console and it has to cobble together a solution in software to make it right.\n\nIn short, when a PC emulates a console, you are asking it to do everything the console does, just as fast, but using its systems. It has to work harder to get it right.", "Quite simply, because you are adding another layer of abstraction to it. \nImagine trying to unscrew a nut while holding the plyers with another pair of plyers. It is certainly possible, but you going to need a bigger amount of force to hold on to the plyers and move the nut.", "The difference is a result of the time cost of emulating hardware registers (storage locations in the CPU and graphics for instructions) in software. The reason is **not**, as some have suggested, to do with translating between differing CPU architectures. In fact, the major console CPU's are using the same CPU architecture as your PC, which is the x86-64 (also known as x64, x86_64, AMD64 and Intel 64) architecture. However, the console processor is packaged in a tight configuration with the graphics bridge that we call *system* *on* *chip*. The exact configuration is secret (proprietary), but it can be reverse engineered and then mapped to your system, which is what the emulator does.\n\nQuick background knowledge: The speed of communication between active memory (RAM) to the computer's brain (CPU) is much slower than the speed of internal communication within the CPU (CPU to CPU) and also slower than CPU to graphics. These external communications are usually ten-times slower (an \"order of magnitude\" slower) than the equivalent internal communication would be. RAM to CPU can be even slower than that, but ten-times slower is a good estimate. \n\nOn your console, your game disc has instructions that read-from and write within the CPU and graphics bridge. These instructions are interpreted very quickly, since they're CPU-internal for the console. \nOn your PC emulator, however, the console's registers are being represented virtually in software, meaning that they're assigned locations in RAM by your operating system. So every time the game reads or writes from these virtualized registers, it takes roughly ten times as long as it would on the console. To account for the lag this would produce, your PC needs to be much speedier than your console needs to be (not necessarily ten times as fast, since most of your emulated gaming experience will not fit the the worst case scenario).", "Emulators need to work like the original. To take care of every tiny detail, the computer needs to do a lot of work. For example every bug, every undefined behavior etc. has to be exactly the same or you'll run into problems. So you have to take care of a lot of stuff that a normal computer doesn't have to care about.\n\nYou can't really emulate anything modern because we have reached certain limits with some of the things. Processors aren't getting any faster for example, world record for the fastest production processor (overclocked) is from 2012. We have reached the speed limit of processors like a decade ago and since we've just made them do more stuff at a time and have multiple processors do stuff at the same time to improve performance and have them try to predict what you're about to do (which resulted in some hilarious bugs that have been in the news for the past month) etc.\n\nMemory isn't faster either, it's limited by pesky things such as speed of light and so on. Stuff we haven't even approached back in the 80's and 90's.\n\nVery sophisticated malware do this, they check for tiny bugs/undefined behavior in the CPU that doesn't occur in a virtual machine/emulator/sandbox so they know when someone is trying to dissect them or figure out what they do.\n\nWhat we do is we FAKE IT. Instead of emulating the whole thing, we just emulate the parts that matter so that programs/games work. You don't need to emulate the whole thing (except for fun), you only need to emulate a small portion of it to make the software compatible.", "The SNES (for example) and the PC don't speak the same language so a program (emulator) stands between the game code and the PC that converts the game code to something the PC can understand. This extra step requires more speed from the PC than the SNES had. ", "Okay ELI5... Imagine you want to solve a riddle. However, the text for this riddle is in French and you only speak English. Before you can even try to solve the riddle you need to translate it in English, which will take you some time, and only then can you then work on solving the logic portion of the riddle.\n\nIt's a bit like that because the ROM your PC reads has computer opcodes meant for a machine that is different from your PC, so they need to be translated to something your PC understands first. Both the console and your PC are able to ADD two numbers, but they say it differently.\n\nBut this analogy does not cover it all because it's not always only about translation: quite often the machine being emulated is capable of operations that your PC isn't (for example, because those are highly specialized operations that have been committed in hardware) and your PC can't just do a one to one translation for those but must rather run multiple of its own instructions to do the same thing.\n\nAs an example, even though the emulated console has a different opcode for ADD then your PC, there is (mostly) an equivalent instruction. But, all the early consoles had specialized hardware for dealing with sprites allowing to display sprites on screen with very simple instructions, whereas PCs don't, so there is no \"natural\" translation for such operations.", "It's very simple, the os is designed and optimized to perform game related tasks. You compile program and design the game for the rules given by the OEM. A PC is a toolbox with which you \"could\" do anything.\n\nSpecialization allows for efficiency but not utility.", "Playing games native to your PC or to your console is similar to reading a book in your native language, you’re only limited by your vocabulary and reading capabilities from understanding it (performance loss).\n\nNow imagine you want to read a book in language you don’t understand because your friends recommended it to you to read it. Before all that you need to learn the language (create the emulator) and learn it’s quirks and vocabulary (optimisation). Problem with all that is you are reading in a language you haven’t grew up with so you will hit into hiccups that will require you to stop and examine or reread them (graphical and performance issues). In the end you will be capable of getting over those obstacles but iťs an eternal pursuit for knowledge to understand that language, so you won’t understand it well in the end, but well enough to have fun while reading the book...", "Because you're not just emulating a software environment. You're emulating all the physical quirks of the physical chipsets used in the consoles. \n\nTo truly emulate a console, you must first perfectly simulate the universe. ", "For one computer to emulate a console (another computer), it must pretend to be the console and run the game as fast as the console does. It is very complicated and time consuming to pretend to be another computer, so it requires significantly more computing power to run the game in time.\n\nLess eli5, a console is hardware (the console) running software (the game). An emulator is hardware (the computer) running software (the emulator) pretending to be hardware (the console) running software (the game). All of the pretending takes a lot of time.\n\nBonus, some consoles, especially older ones, have hardware flaws. Some games depend on those flaws to function. So, good emulators must deliberately have those flaws.", "One reason is that there is some instructions that may not exists or are different. For example, if your console have a \"multiplication\" opcode, but the host pc do not, then it need to emulate it. Some instructions on the console may also be more optimised, so the same multiplication on the console could take 2 cycles while on the pc it could take 6 cycles (3 times slower in this case).\n\nSome console might also have a reverse order for the bit storage. PC use the same order as us, the most important bit on the left (or first). Like us, the thousands are before the units. But on some it's the reverse: least significant bit first. Want to store \"twenty five\"? A PC will store \"25\", while an old mac using the motorola cpu would store \"52\" (actually, 00011001 on pc, 10011000 on the old mac). This mean that it also need to swap it.\n\nNot only that, but the video card is custom made for them, and may not have the same functions as your. Same with the sound card.\n\nFor example, I beleive the NES basically have this: channel 1, set to squarewave, play tone 440Hz. Channel 2, set to triangle, play tone 587Hz. (half a second later) stop channel 1, stop channel 2. and so on. On a pc, this need to be emulated. The sound card in a pc can NOT do that. All it can play is a sound sample. So you actually need to make a subprogram that will generate the waveform in real time (there is some ways to cheat however), then feed the data in real time to the sound card.\n\nSome video features may not be available on the pc too. The same need to be done: redo it in software instead of doing it in hardware.\n\nOf course, there is way to reduce the overhead, for example, if it use the wrong bit order then swap all of them in the code, and swap the related instructions too, like \"shift bit left\" become \"shift bit right\". This can be done before starting the game. Some other instructions can also be replaced for the pc equivalent sometime, which allow to run the code more... nativelly. But it is still emulation, and it can't be run directly.\n\nThen you ends up with some more insanity: modern console have an OS behind it, which provide some functions. Those are not much documented and have been reverse engineered to figure out what it do. That reverse engineering introduce bugs (or fix some, which may have been exploited), and may not be as optimised as the real one, in part because the hardware can change. Intel and AMD don't offer all the same opcodes. Same with a core2 vs an I5 for example. So those functions need to be more generic. On the real hardware they can sometime cheat, as they know that the hardware is always the same.\n\nAnd again, same thing for the emu, since the hardware change, the functions can't be as optimised for one hardware in particular. Sometime you can cheat knowing that this cheat will work, ex: a division by two take more time than shifting bits. The human equivalence is a division by 10, you can do the full division, or move the dot one position. If you know that this work on your hardware you can do that cheat, if there is a doubt then you need to do the full operation...", "\n\nConsoles basically read game then the gpu outputs visual.\n\nA pc is not streamlined.\nA pc has to read it, put it into memory, and many more steps which require more power to do properly.\n\n\n", "Answers are good but this needs to be said.\n\nBy powerful you think how much CPU cycles you can execute and maybe how many video texture or pixels you can push. However you're not just emulating the consoles CPU with your CPU you got to emulate the video hardware with your CPU and audio too if it uses specialize hardware. It isn't just copy/pasting the memory contents cause that'd be easy.\n\nOn the NES in video memory it can represent one 8x8 tile (2 bits per pixel) using 16bytes of memory. To draw that on modern hardware you have to take the NES video memory, then translate it to 192 or 256 bytes (RGB or RGBA) then give it to your video hardware. PCs speak RGB not the specialized NES video memory. NES can't speak HDMI. It's stuff your CPU has to do and your CPU isn't even emulating the consoles CPU during this.\n\nThere's also another problem. Games might take advantage of hardware timing which means you cant just translate the results you have to translate steps which is more work. For example the NES might be able to scroll the screen however it can not scroll the screen at two speeds [yet it has been done](_URL_0_). The trick is by using some cartridge hardware (less common) or by using sprite 0 collision (which is built in to the NES) to trigger a hardware event. When the event happens the game pokes the video hardware to use a different background X axis which causes it to draw at a different location.\n\nTo emulate the effect you can't just look at the video memory and draw it. You'd have to draw one or a few pixels, execute the CPU/hardware then draw the next pixel or next few pixels. It'd be easier to translate one video memory to another but you wouldn't get the effect. Without it the game will look wrong or the game won't work because it didn't receive important hardware events at when it was suppose to receive them. \n\ntl;dr: You don't use CPU to emulate CPU and video to push video memory, there's more to it.", "First, a console is just a computer. \n\nSecond, your PC is also just a computer. \n\nSo your PC essentially (for laymen’s sake) is working twice as hard... to run itself, and to run the other computer (the console, which is made of software when emulating it). Thus you need a PC significantly more powerful than JUST the console you are emulating for it to run smoothly.\n\nIgnore the long-winded answers that get technical. It’s really this simple on the surface. ", "The software a computer can run needs to be in a language that it can understand. We can program any software in a variety of languages, but it is compiled according to a specific Instruction Set Architecture. x86 is the standard now for desktop PCs. This means that the CPU, on a hardware level, understands *only* x86 instructions.\n\nOld consoles, or any other type of computer that can be emulated use different hardware, with a different CPU that doesn't understand x86. So if you want to emulate an N64, or Android phone, or a graphing calculator, you need to write x86 compatible software that will understand the native language of the software you are trying to run. You can't run an N64 game natively because the instructions in that code cannot be understood by your CPU. So this abstraction layer sits between that game and your hardware and translates everything on the fly. That is inherently very taxing. It's a lot of work, a lot more than just running that software on hardware that was made for it.", "Imagine your console is like a secretary. Your console dictates a memo out loud and the secretary types it.\n\nAn emulator is like this: now the console is dictating a memo, but the memo is in English and your computer only understands Spanish. So the emulator translates the memo to Spanish and the secretary then types the translated memo. Only, your computer has to be both the secretary and the translator. ", "Imagine you're trying to read a book in your native language. Easy right? Now imagine you're trying to read a book in another language, but you have a dictionary. So you have to look up every word. Take you a LOT longer right? You finish the task much slower.\n\nSo to read the same speed as a natural speaker, you might need to be able to read, and search through the dictionary, ten times as fast, or more.\n\nThat's emulation.", "Because your Nintendo only has to run the video game, whereas your computer has to simulate the Nintendo that runs the video game. The bare metal video game system becomes a program on a general-purpose computer. It takes resources to run a virtual machine on your actual machine because its hardware doesn't actually exist.\n\nIt's the difference between cooking breakfast and building a robot to cook your breakfast.", "You are mimicking hardware in software.\n\nHardware pieces are made for specific reasons, mostly speed and efficiency. When you make a software version of them, they run slower than in the real world because physics is essentially being simulated instead of used. \n\nSo, ELI5?\n\nA puppet might only need 4 strings to function properly, but the person controlling it needs more than those 4 things to control the puppet.\n\nAt the least, a puppet that can emulate all the function of the smaller puppet needs to be able to hold the puppet and move it up/down and left/right (two more things the first puppet doesn't need to do).\n\nThe same goes with a puppet controlling a puppet controlling a third puppet. The first puppet has 4 strings, the second has 4 + two strings to move the puppet left and right or up and down, the third has the original 4 plus the 2 to control the second puppet plus two more to control the second puppets up and down and left and right movement, and so on..." ] }
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[ [], [], [], [], [], [], [], [], [], [], [], [], [], [], [ "https://www.youtube.com/watch?v=ltuRuGM271Q" ], [], [], [], [], [], [] ]
9m8msb
why do all your joints ache when you have an infection?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/9m8msb/eli5_why_do_all_your_joints_ache_when_you_have_an/
{ "a_id": [ "e7d2ng6" ], "score": [ 82 ], "text": [ "When you have an infection, your body fires up an immune response. Think of your body's immune response as the SWAT team. \n\nWhen you first get infected, a minor response is made by the body.. cops are called essentially. 8/10 times Cops get the job done. Sometimes, the cops are not equipped well enough, so SWAT is called. SWAT basically goes everywhere and causes inflammation while fighting away the infection wherever it may reside. \n\nThe inflammation causes your joints to hurt :) \n\nTl; dr - Infection causes immune response and inflammation. Systemic inflammation causes joints to ache. \n\nSource: Med student\n\nEdit: Grammar" ] }
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2xweg7
why is it considered desirable to serve hot school lunches?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2xweg7/eli5_why_is_it_considered_desirable_to_serve_hot/
{ "a_id": [ "cp3zfiq" ], "score": [ 2 ], "text": [ "I think [this blog entry](_URL_0_) sums it up quite nicely.\n\n > Researchers found that one in 10 [6 to 8 year olds] was eating half the calories recommended for their age – 3.5 per cent missed at least one meal a day.\n\n > For many of the children the diaries were stories of missed breakfasts, meals without meat or vegetables, little snacks providing the bulk of the day’s calories.\n\nBy providing children with at least one hot, nutritious, balanced meal per day, we hope to educate children in how to eat properly, and at least go some of the way towards ensuring that all children get the nutrition they need." ] }
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[ [ "http://blogs.channel4.com/jackie-long-on-social-affairs/growing-number-hungry-children-poverty-britain/858" ] ]
4e3w2j
how do all the scams promising you six figures, just by sitting at your computer and clicking you finger actually work? what are their purpose? how people allowed to get a way with such malicious activity?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4e3w2j/eli5_how_do_all_the_scams_promising_you_six/
{ "a_id": [ "d1wrvwh", "d1ws0ak", "d1ws0hk" ], "score": [ 11, 3, 2 ], "text": [ "Their purpose is to trick the greedy and the easily fooled into sending the scammer money, giving the scammer bank details, or simply performing work for which they will never be paid.\n\nPeople get away with it because the scammers are usually based in countries with incompetent or corrupt law enforcement.", "Some might also be pyramid schemes: people get paid for doing something and also get paid for each recruit they get to do the same something. And sometimes paid for anyone their recruits recruit. So the incentive becomes recruiting people and spamming people becomes common.", "Sometimes they are affiliate programs, particularly pyramid scheme-type programs. In theory it is possible to make money from home just posting links here and there, if you get enough people to ALSO click your link and sign up. \n\nThey are allowed only because law enforcement has a hard time catching these scumballs. " ] }
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2xwoz2
why is "salt of the earth" considered a good thing.
in ancient times salting the earth was done to poison the croplands of your enemies, making sure that they could not live there again. this makes "Salt of the Earth" seem a very bad thing.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2xwoz2/eli5_why_is_salt_of_the_earth_considered_a_good/
{ "a_id": [ "cp420ms", "cp422v6", "cp4361h" ], "score": [ 13, 6, 2 ], "text": [ "The expression is from the bible.\n\n_URL_0_\n\nSalt is very important - it is used as a preservative, a component in fertilizers, and for ritual sacrifices (salt is used to drain the blood out of an animal after the slaughter). Salt is also considered \"pure\" (therefore salting the earth causes the earth to be pure of any living thin).", "Though they sound similar, they have different origins. \"Salting the Earth\" does refer to poisoning the land of a conquered city. \"Salt of the Earth\" comes from the following Bible Quote:\n\n\"Ye are the salt of the earth: but if the salt have lost its savor, wherewith shall it be salted? it is thenceforth good for nothing, but to be cast out and trodden under foot of men.\" - Matthew 5:13\n\nIn context it means a dependable person.", "\"Salt of the Earth\" is from a bible quote. And it references mining salt as a precious resource. \n\n\"Salting the Earth\" while sounding similar in English is not the same reference point. That is referencing the practice of poisoning land after you have conquered a region. " ] }
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[ [ "http://en.wikipedia.org/wiki/Matthew_5:13#Salt_as_a_metaphor" ], [], [] ]
7qak2x
how do tvs magically turn themselves back on after being switched off?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/7qak2x/eli5_how_do_tvs_magically_turn_themselves_back_on/
{ "a_id": [ "dsnoiax", "dsnopok" ], "score": [ 2, 2 ], "text": [ "They're still plugged into your wall - electricity is still flowing if it is needed. The TV is just waiting for the correct IR input to send power to another parts of itself. ", "modern TVs are little computers. \"off\" usually puts them into a low energy state, because having to boot every time you want to watch TV would be unacceptable. some internal processes can bring computers out of these sleep states. updates are a common example. " ] }
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383p81
why does the us have such a vested interest in the middle east?
Compared to many other issues of foreign policy, particularly drug cartels in Central America, why is so much time and effort spent deliberating the Middle East. Why doesn't the US just leave the Middle East be?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/383p81/eli5why_does_the_us_have_such_a_vested_interest/
{ "a_id": [ "crs0auz", "crs11fx" ], "score": [ 12, 17 ], "text": [ "In simplest terms, the answer is oil. America wants it, Saudi Arabia has a lot of it, so America allies with them closely. The Sunni/Shia conflict makes the US allying with them very complicated, it's what led to Bin Laden's 9/11 attack. ", "1) Oil. It's essential to our economy, and the Middle East is a large enough supplier that chaos there causes lots of economic harm in the US.\n\n2) Israel. Some bad things were done to Jews prior to WWII, and part of the world's reparations to them was to grant the Jews their longtime wish, a country all their own in Palestine. They picked the Middle East, but the US is the enforcer of the world's decision. \n\n3) Broken Windows. When bad things are going on in an area, bad folks move there and set up shop. The Middle East has been broken since the Treaty of Lausanne broke up the Ottoman Empire following WWI. The British (the US of the day) decided that breaking the empire up into several countries of mixed religious and tribal heritage would encourage the development of secular governments. That mostly didn't happen, and the resulting wars and failed sates are evidence that it might not have been a good idea. Failed states that let nutty Madrasahs teach the value of being a suicide bomber can lead to big problems for the US. It ignored the situation in Iran for decades under the Shah, and the revolution that followed proved the harm that comes from not taking a vested interest." ] }
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3b4z5j
why does tuna have to come "in water" or "in vegetable oil?" why can't i just get some tuna?
I just want plain tuna!
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3b4z5j/eli5_why_does_tuna_have_to_come_in_water_or_in/
{ "a_id": [ "csiw4zs", "csiwljq", "csixcc3" ], "score": [ 9, 2, 2 ], "text": [ "Because it's seafood. Seafood does not last for long, and if you want to eat some tuna in Nebraska, you'll have to accept the current systems that we have for keeping it fresh enough to eat.", "The liquid takes up the space of the air in the rigid tin. Air would cause the food to spoil. Unlike say a vacuum sealed packet which is flexible enough to have the air expelled completely. That method would ruin the tuna by essentially destroying its structure.\n\n", "From what I recall the tuna is canned before it's cooked, then the whole can is heated to make it safe to store. Without the liquid it might not be free of bacteria because it would need to be heated longer. \n\nYou can actually get vacuum sealed tuna pouches that aren't boiled to hell, and they're way tastier but also more expensive. " ] }
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6s44e5
why do some banks force users to create bad passwords?
For example, one popular bank where I'm from (not mine, thankfully) requires passwords to be exactly 8 characters, no special characters, not case sensitive. Shouldn't banks allow (or force) better passwords than that? Is there an actual reason for this other than bad programming?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6s44e5/eli5_why_do_some_banks_force_users_to_create_bad/
{ "a_id": [ "dl9wz51", "dl9wzbn", "dl9x8u6" ], "score": [ 20, 2, 8 ], "text": [ "I'd be extraordinarily suspicious of that bank. \nBelieve it or not, the Bank's password security might WORSE than you think. \nThe likely reason is that the passwords are being stored in regular sized chunks. \nSo if you have a space 64 characters long, you would know that there are 8 passwords, and character 8 is the start of the second password. \nSo it takes much less space and can be checked really quickly. \nThing is, NOBODY SHOULD **EVER** DO THIS! \nA password should be stored after it's been put through a mathematical function called a hash function, and with bits added to it so that it's a standard length called a salt. \nThat way if someone ever steals the list of passwords, it's functionally impossible to get back the original password. \nThe math works out so that you can quickly turn a password into a series of numbers, you can check if two numbers were made from the same password, but it's really really hard to turn the numbers back into a password. \nBy storing it like that, you made the entire list extremely vulnerable, any IT tech with access can see everyone's passwords. ", "When a password is saved into a database it is generally all jumbled up (and it can't be unjumbled) so that hackers can't read your password (or staff members for that matter) if they get access.\n\nWhen you type a password into the website it will jumble what you type and see if it matches the saved password jumble on file.\n\nDue to poorly coded old systems - which are very expensive to rebuild - banks may have old code that doesn't support more complex newer passwords.\n\nBut I know that my bank, and many others, allow long alphanumeric passwords (Australia)", "100% bad programming, no reason for it, it is actually worse than you imagine.\n\nAny good web service like Reddit stores passwords in a rather interesting way. Well, rather, they do not store the password. Let me explain.\n\nGood services will not store people’s password, they will store what is known as the hash of a password. A hash can kinda be described as a fingerprint of a set of data, a hash is a relatively short number that is created after running a set of data through a hashing algorithm. Ideally, you cannot reverse this operation, you cannot generate a set of data to satisfy a certain hash, but every time you run the same data through the hashing algorithm, it produces the same hash. For example, the SHA256 hash of “password” is 5e884898da28047151d0e56f8dc6292773603d0d6aabbdd62a11ef721d1542d8.\n\nNow, you can go to any SHA256 calculator online and input “password” and it will give you that hash. But if you didn’t know that data I used to make the hash, you cannot find it without just trying every possible data.\n\nSo, for security purposes, logging into Reddit for example involves you sending Reddit your password, them hashing it, and checking if that hash is in their database. This is all done so that in case the database is leaked, no passwords are leaked. After verifying that you are who you say you are, the password is deleted from memory.\n\nNow, the thing is that there are no restrictions on which alphanumerical/symbol characters you can input to the hashing algorithm, it will make a hash for all of them. It also doesn’t matter how long the data is, it could be a password that takes up gigabytes, it will still make a hash 64 characters long like above. This means that the bank is likely storing the passwords in a file that doesn’t support certain things, and this is bad, very bad, if the database is leaked, there goes all your money. There is no reason to have such a restriction with hashes password database security.\n\nDO NOT USE THIS BANK" ] }
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exeio8
in countries where health care is free, where do the doctors, nurses, emt's, etc, get their income from?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/exeio8/eli5_in_countries_where_health_care_is_free_where/
{ "a_id": [ "fg7r01l", "fg7r0oj", "fg7r5hl", "fg7r7hw" ], "score": [ 11, 2, 3, 2 ], "text": [ "From the government. Usually people in countries with free healthcare etc pay a little more in taxes so that the money can be used to pay for these services.", "People pay taxes. Taxes go to government. Government allocates funds for various things, including healthcare. This includes workers' wages as well as all other expenses.", "The government. Same as any government employee. You pay your taxes and the government uses those taxes to pay wages. This is the case for the majority of health workers in public hospitals. \n\nIn Australia even though we have a free health system, we also have a private system and some people choose to work privately. \n\nDoctors who choose to work privately can charge more and the patient can get a rebate on the portion of the few that is covered by the government. \n\nThat’s the short version. Our health system is very convoluted and complex. \n\nSource: 3rd year med student in Aus", "Here in Australia we have the government health system (medicare) and the private system.\n\nMedicare sources it's income through taxes and levies.\n\nMedicare doesn't cover everything; unless you have a government issued health card (pensioners, unemployed etc) you have to pay \"out of pocket\" for some services i.e. majority of dental.\n\nPrivate health insurance covers some of those out of pocket expenses." ] }
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46ehhz
after the first world war, nearly every country in europe must have had a shortage of men. how were there enough men to fight in world war ii? is there still a gender imbalance in europe?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/46ehhz/eli5_after_the_first_world_war_nearly_every/
{ "a_id": [ "d04euum", "d04ewbx", "d04ewld", "d04gues", "d04t6k0", "d04xi5i", "d04y2ia", "d050n0h" ], "score": [ 2, 106, 31, 22, 2, 4, 6, 2 ], "text": [ "World war 1 ended in in nov 1918. Ww2 started in sept 1939. That's 20 years. Germany and the us experienced a baby boom and economic boom both times afterd each war.", "November 11, 1918 is when ww1 ended, \nSeptember 1, 1939 is when world war 2 began, \nThis is 21 years.\n\nMost soldiers are ready to fight at the age of 18-21", "WWI while costing the lives of a lot of soldiers kept combat fairly confined to the front lines for a war of its magnitude. As such there were not massive numbers of civilian casualties (there were some) like there were during WWII. That means that the children who were already born before the war were able to grow up to fight in the next. You also had a baby boom after the war, like you do after most major wars, that helped to provide soldiers as well. ", "And there was the 1918 Spanish Flu that took an estimated 50-100 million lives of which roughly half would've been males. The war took 17 million.", "Most countries allowed their soldiers trips home during the war, so the birth rate wasn't too badly affected. France had some different policies and the resulting lack of population growth was a major reason for them building and relying on the Maginot line.\n\n\nPopulation graph of France through the wars here for a good indication of how hard the entire country was affected;\n\n_URL_0_", "51% of babies born are boys, and the average loss in WW I was 1.5%, so overall there was no shortage of men after WW I. However, the loss was concentrated in the military aged men 18-31, so there may have been a disproportionate shortage of men in that age group.\n\nWW II happened 20 years later, so there was a new cohort of military aged men.\n\nThere is a slight gender imbalance in Europe today, like 1.02 men to 1 woman age 14-65.", "Another thing to consider is that, even if there was a gender imbalance created due to the war, it would have no effect on the ratio of boys-to-girls born to that generation. Essentially, the subsequent generations would have a balanced ratio. So, to answer your last question, if there were any gender imbalance near WWI/WWII, it would have long been averaged away by a balanced ratio of boys and girls being born during and after those time periods (and moreso by the death of those alive during that time).", "Not ever country recovered (numerically) from WW1. Prior to 1939, France was suffering a manpower shortage due to net losses during WW1 and a low birth rate. \n\nThe logic of the French two man tank designs and part of the fighting doctrine were developed with this problem in mind. \n\nThe issue also considered in the construction of the Maginot Line as it required a lower level of manpower to maintain and operate compared to free standing divisions. " ] }
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[ [], [], [], [], [ "https://upload.wikimedia.org/wikipedia/commons/4/43/Population2Centuries.jpg" ], [], [], [] ]
495jk9
why can't you feed peanut butter to babies of a certain age? does this have to do with peanut allergies becoming more common?
I don't know if this is because I wasn't aware of it, but when I was a child peanut allergies didn't seem to be a very common occurrence. I'm wondering if it's a new practice to keep babies of a certain age from eating peanut butter, that was it around as much when I was a child. Is this the case? Or is it just something that I am noticing now as an adult? Perhaps used to be more common for people to die of a peanut allergy without even knowing they were allergic to peanuts. I don't know.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/495jk9/eli5_why_cant_you_feed_peanut_butter_to_babies_of/
{ "a_id": [ "d0pbrv0" ], "score": [ 2 ], "text": [ "The latest science suggests that feeding babies peanut butter (when safe) reduces the number of allergies. Weaker science suggests that peanut oil in children's products for external application are a part cause of the allergy. It's similar to eating local unfiltered honey to become less allergic to the local pollen." ] }
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6mbkg9
why does the airplane window feel hot to touch when it's - 40c at 40,000 feet outside during a sun
[deleted]
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6mbkg9/eli5_why_does_the_airplane_window_feel_hot_to/
{ "a_id": [ "dk0e6l4" ], "score": [ 2 ], "text": [ "Because things heat up when you hit them with light and when you're up in an airplane you're closer to the sun and getting hit with more light.\n\nBeing higher up means the light from the sun has to travel through less air to hit the window. At 35,000 feet, a common cruising height, there sun's light has only gone through 1/4 of the air it's going to go through, so theres more light hitting the window than if it were at the beach. This heats up the window a lot. What makes this an even bigger effect is the fact that most planes have 2 windows so the outside window is keeping all the cold air out but not most of the light. " ] }
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4vq88k
depth of field re: photography
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4vq88k/eli5_depth_of_field_re_photography/
{ "a_id": [ "d60i1p2" ], "score": [ 6 ], "text": [ "Depth of field is essentially \"What is in focus\" in an image. Think of putting your camera on your kitchen table and setting cups close, medium, and far away from the camera. If the entire image is in focus, you have a long depth of field. If one of the cups is in focus and the others aren't, you have a shallow depth of field. You can put the focus point anywhere, it's just a distance from the camera that will be in focus while everything else is out of focus." ] }
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7kzd01
what is that newborn baby smell and how does it stay for weeks?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/7kzd01/eli5what_is_that_newborn_baby_smell_and_how_does/
{ "a_id": [ "driysue" ], "score": [ 43 ], "text": [ "You mean the one from the head? Those are pheromones released by the baby to make people love them. It's almost intoxicating, and even stronger if the baby is yours.\n\nAnd yes, humans are subject to the effects of pheromones." ] }
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3hh3lo
what exactly is spicy?
It seems weird, like most other things have direct effects and can be easily seen/measured (e.g. temperature, acidity) but this seems really vague, like the only way to detect it is touch/taste? How are there exact numbers on the amount of spiciness something has? Why does it feel like burning? Does it actually hurt you or is it just an illusion? Why does it only occur in chillis? Is it basically a poison to stop things eating them? But isn't the whole point of the fruits to be eaten and pooped out so the seeds are spread all over the place? Lol help please
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3hh3lo/eli5_what_exactly_is_spicy/
{ "a_id": [ "cu7aecg", "cu7ahlj", "cu7ahng" ], "score": [ 2, 5, 3 ], "text": [ "You can directly measure how spicy something is. Spiciness is the presence of a chemical called capsacin, and its measured via the scoville scale. ", "spiciness is generally caused by a chemical called capsaicin. Capsaicin triggers the temperature sensors in your mucous membranes which basically makes them tell your brain that the area is burning hot. You're not actually being burnt, but too much capsaicin in the wrong place can be very damaging to your body (or at the very least extremely painful). \n\nEvolutionarily, the capsaicin is helpful because it doesn't effect birds but does effect mammals. Mammals take seeds a shorter distance and also more commonly destroy through chewing than birds do.", "There's a thing called the Scoville scale, which is based on capsacin concentration in the food. But if I recall correctly, it's basically related to tasting. You can also do chemical analysis on it to actually find the concentration of capsacin, but Scoville heat units are much more common.\n\nCapsacin is a chemical which can force heat receptors to trigger. Your body literally thinks the temperature is increased, which is why it feels like burning and makes you sweat if you have a lot.\n\nAs for why plants produce it? It's because birds can't taste it. It only effects mammals (which is why you can douse your birdseed with it to keep the squirrels out). Birds will spread the seeds much further than mammals will." ] }
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chzln2
if gravity is always pulling down on us wouldnt it be considered an infinite source of energy?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/chzln2/eli5_if_gravity_is_always_pulling_down_on_us/
{ "a_id": [ "euzr3fh", "euzr4lj", "euzr5tr", "euzra3p", "euzwti5", "euzzk3t", "ev0de2h", "ev87j8d" ], "score": [ 2, 2, 40, 6, 3, 3, 2, 2 ], "text": [ "Not infinite because eventually whatever is being pulled by the gravity will become a part of the mass that is causing the pull.", "But how do you harness it?", "No. You can get energy out of things by letting them fall, but you'd have to use just as much energy to raise it back up and repeat the process.", "The energy is stored as a potential when an object is just stationary and experiencing a gravitational pull. Say when an object is held at a certain height.\n\nThat energy is released and turned into kinetic energy if you release the object and it falls. \n\nYou would have to do work to return the object to its original height, restoring the gravitational potential energy.", "Potential energy is the energy something has from its position near to something exerting a force. Gravitational potential energy, the energy an object has due to being apart from the mass attracting it, is simply gravitational force multiplied by height from the surface (not infinite).\n\nIn a couple of other comments you've mentioned lifting something back up using solar - when you go through that process, you're reducing the height of the object, lowering it's gravitational potential energy, and extracting some of it for use. You are then topping it back up with solar energy when you lift it again. In this situation gravity isn't a source of energy - its storage for solar.", "If you stretch a blanket/sheet and put a bowling ball in the middle, it will form a dip. If you drop a marble on the sheet, it will go towards the middle until it hits the bowling ball. \nGravity needs a mass and interacts with other masses. It's not infinite because the masses will collide with eachother. \nGravity might *appear* to be infinite because two point masses can be infoni8small, but that's stepping away from ELI5 and more into calculus/physics.", "Since the gravitational force is uneven around the globe, would it be theoretically possible to create a \"gravitymill\"? If the left side of the mill has more force acting on it than the right side, wouldn't that cause it to be pulled down more than the right side and therefore creating a rotation? This construction would might have to be crazybig, but you know, in theory?", "You do work by being able to use a force over and over. With gravity you have what is ultimately an acceleration (not actually a force) and to “reset” it you’d have to climb back up the gradient and fall again. The work you’d put into climb back up the gradient would cancel out the benefit you get from ‘falling’ in the first place. There is no known way to block gravity, it seems to permeate all things (otherwise we could just make a big Ferris will and block gravity on just one side, boom, infinite power!). Same argument could be made for magnetism, you have access to an always on magnetic force generator, but without putting something else in you can’t get work out of a magnet.\n\nNobody knows exactly how gravity works. General relativity correctly points out that mass has the effect of bending space itself which has an effect that we perceive as gravity, but getting to a finer level of detail (like say how gravity behaves at the quantum level) is still a huge goal of modern physics. At present there is no known way to generate gravity short of either accumulating a lot of mass together, so we can’t just turn it on or off, and we can’t block naturally occurring gravity. Some things are just still outside of our grasp as a species for now, understanding everything about gravity is still one of those things." ] }
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1e0pq6
why does sweating it our work so well in getting rid of colds?
It's common advice to cover yourself up at night and induce a lot of sweating to get rid of a cold. I've done it three different times now and it's worked successfully.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1e0pq6/eli5_why_does_sweating_it_our_work_so_well_in/
{ "a_id": [ "c9vpg5v" ], "score": [ 4 ], "text": [ "I don't think there is any medical basis for this. You probably just got a good night's rest in and you have a good immune system so you got over the cold quickly. \"Sweating it out\" doesn't do anything for a cold\n\n_URL_1_\n_URL_2_\n_URL_0_" ] }
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[ [ "http://listverse.com/2008/11/05/top-10-myths-about-the-common-cold/", "http://abcnews.go.com/Health/ColdandFluNews/story?id=5718776&amp;page=3#.UYwKLLWmiAg", "http://www.cbc.ca/stevenandchris/2012/11/busting-common-cold-myths.html" ] ]
6hwpo3
what makes debts you owe be removed / halved in what you originally owe from debt collectors?
What makes debts you owe be removed / halved in what you originally owe from Debt Collectors? I'm asking and wondering because before me and my wife got married, she had tons of medical bills that she couldn't pay and they went into collections and a year later I was wondering how some of her bills got removed (some were removed and some of the bigger ones were consolidated into a bigger bill I assume?) as well as they offered her if she paid half of the amount that the bill / bills would be considered paid in full? I always thought you'd have to pay the full amount.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6hwpo3/eli5_what_makes_debts_you_owe_be_removed_halved/
{ "a_id": [ "dj1paxo" ], "score": [ 3 ], "text": [ "Often times the original company you owe the money to, sells the debt for less than the original and writes it off as a business loss. For some businesses this is a better choice then spending money trying to collect the debt from you. The company that buys it will try and get you to pay them more than what they paid for it, but that is often less than the original debt. \n\nOther times, if the company doesn't active try to collect the debt for a certain period of time, the debt is cancelled. You no longer owe the money to the company. However, be careful, because the federal government considers cancelled debt as income and will tax you on it. " ] }
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2t22el
who is actually falling for internet "one weird trick" ads? what happens to those people who do fall for the scam?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2t22el/eli5_who_is_actually_falling_for_internet_one/
{ "a_id": [ "cnuzqwx", "cnuztpm", "cnuztyd", "cnuzw92", "cnv00p1", "cnv013v", "cnv03kr", "cnv03pp", "cnv058d", "cnv06qe", "cnv07lc", "cnv09un", "cnv0hmh", "cnv0jqn", "cnv10go", "cnv1r8t", "cnv1wb9", "cnv276q", "cnv28wx", "cnv2i54", "cnv2rc0", "cnv3z7s", "cnv4im9", "cnv6ngu", "cnv70s5", "cnv7ds1", "cnv8153", "cnva59e", "cnvce0j", "cnvgf8z" ], "score": [ 63, 121, 825, 42, 2, 19, 2, 10, 18, 5, 37, 2, 5, 2, 2, 3, 2, 2, 2, 3, 14, 7, 5, 3, 2, 2, 2, 3, 2, 2 ], "text": [ "Not so much the \"one weird trick\" ads but the \"your computer is infected with viruses click here to fix it.\" I have friends and family who are generally smart that legitimately think it's from their antivirus software. I can't tell you how many times I've had to run malwarebytes because of this.", "It's a way of getting only the most gullible people to respond, much like Nigerian 419 scams. Good article on Slate about it here: _URL_0_", "As someone who works for a credit card department in a bank I can give some insight. So people actually fall for the more often than you think. I personally speak to at least 1-2 people a day about this. \n\nGenerally what happens is they sign up for a free sample, just pay for the shipping it says usually. What they didn't bother to read is that this is entering them into a subscription contract. If they do not cancel within x days they are billed full price for the sample and it is non-refundable. \n\nNext, this subscription becomes a monthly recurring charge and they are sent a batch of this product monthly as well. Now sometimes they will refund you if you send back the product, very rare from what I've seen. \n\nIt's generally a headache to deal with those companies, most times they're actually all off-shoots of one large company. Since they have all these things in their terms and conditions, we don't have any legal rights to dispute the charges for our customers. ", "I know for the car insurance ads, they get you to give up your information and then sell it to lead providers. Say y do give up your information for \"the 6 things insurance companies don't wan't you to know,\" you will get 8 calls from 8 different agents in 10 minutes. Source: I'm an insurance agent and I've purchased these leads before.", "They don't come on the internet anymore because they're too busy now that they've succesfully won so much money. They just don't have time for the internets anymore because they all have successful business' to run where they implement the tricks that we've been too blind to see.", "The \"one weird trick to [X]\" ads probably target the sort of person who wants to [X] and would like to learn an easier way to do so.\n\nFor instance, \"One weird trick to lose 10 pounds in 10 days!\" would appeal to people who want to lose weight (not a small market) and *may* be interested in a new idea for how. The 'trick' may be old hat (stop drinking water and you'll be dehydrated and look good on the beach - this actually works if you want to look thin and have a nagging headache for your entire vacation). There's a lot of people in this category, because weight (and beauty) is a big issue in US culture, and it can be very difficult to make changes in one's body type long-term. If you just want to look better than your average for a few days, there a several tricks that will get that result.\n\nKeep in mind two points: if only one in a thousand people who see the ad click on it, and they show the ad to 10 million people, that's still 10,000 clicks. If only 1% of people who click decide to buy, that's still 100 sales.", "Apparently enough people that they continue to run them.. Sadly.", "They get you to tick a box on a form or on a website which is a contract which says you will buy X number boxes of [insert worthless pill/bottle of snake oil here] at a price of [insert ridiculous amount of $$ here].\n\nYou then have to buy, for example, 200 boxes of coffee beans (worth $2) for $1500. A bit like a cellphone contract, once you sign you have to pay, even if you dont want the products. No refunds.\n\nCoffee beans are common as they are sold as 'miracle natural diet beans'. The most common trick is to get a cheap foodstuff which is not very well known in USA/Europe and sell it as if it is a miracle food or cure for an ailment. E.g. 'green coffee' slimming beans, which are *ahem* coffee beans, or 'pink salt', which is.. er.. salt.\n\n\n", "**ONE WEIRD TRICK TO ENLARGE YOUR DINGDONG!** \n\nOh psh I don't need that. \n\n\n *click* ", "Most use the same tactic of some local mom or such claiming that using these 2 products simultaneously works amazingly well. The fact it is 2 products not only doubles the scam, but add some believability to it as just using one product by itself doesn't seem like a cool secret.\n\nConveniently, both the products are free! You just pay shipping with your credit card, which actually signs you up for large monthly expenses for more product. Now you have to try to cancel 2 different orders while they continue to bill you and send you overpriced worthless product. ", "People like my grandmother. She gives zero fucks and believes everything she reads on the Internet in those ads. \n\n\"Free stuff\" turns into me having to deal with credit Issues and a bunch of headaches. ", "You end up paying a ridiculous price for some normal acai berry capsules, and your penis is still the same size. ", "First I need to be gilded then I'll let you in on the trick ", "I do these once in a while. You get a free one month supply, but they sign you up for a subscription. The \"one weird trick\" is to write down the cancelation number before you enter your info (because you'll never find that number again) or just use a gift card to sign up. I've received some okay stuff for free, and the cancelation phone calls are always pretty easy. ", "Reddit loves to mock ads like this, but the fact is they are so prevalent because THEY WORK. Lots of people click them - if you want an idea of how much the top guys running these types of ads make, read about the case of [Jesse Willms](_URL_0_) who is still at it today\n\nedit: and they have extremely sophisticated methods of testing different headlines and images, analyzing the results and running only the ads that make them the most money, which often ends up being the seemingly hilariously bad 'one weird trick' ads.", "This one weird trick will keep all weird trick ads out of your feed forever! Banks don't want you to know!", "Simple way to cancel this. Call your credit card company and report your card stolen. Then when they try to bill you, they can't. At least I'd imagine that would work. ", "Since I have adblocker, I had no idea what \"one weird trick\" was and had to do a google image search to find out.", "I worked at a call center and we handled these sales and calls. \n\nPeople are stupid. Companies aren't trying to help you, they're interested in profit. \n\n'Free' and 'Risk Free' are VERY different. Risk free means if you aren't satisfied you can jump through ten hoops and cancel. \n\nLegally companies have to have box to check that says 'By placing my order I agree to the terms and conditions and am aware I must cancel within 7 days to avoid being enrolled in the auto continuity program'. --don't fucking check a box without reading it! People say they never checked the box but if you try to place an order without checking the box, it won't be placed. \n\nA ton of people sign up for everything than dispute it. One customers email was [email protected]. My favorite products were campaigns that didn't cave to the AG, FTC, BBB or in the UKs instance, the royal police, meaning no refund for you! If you're stupid enough to order a product that will help you lose 50 pounds in a month while still shoving McDonald's down your throat then you deserve to eat the charges.\n\nWe had people call bitching that we stole money and now child number 3 has no diapers. Well instead of ordering pills online, take your precious kid for a walk. \n\nThe companies itself are shit, not just the idiots who order. They wait for Dr. Oz to spew bullshit to his viewers and they jump to create the new wonder drug. Garcinia Cambodia, raspberry ketone, green coffee bean...ever wonder why there's SO many companies offering this amazing deal? Because it's bullshit and you'll buy into it. The hire a call center, or in my case a marketing group. We handled over 100 products, some agents would be dedicated but most were in every campaign, each with different refund offers and save options. Calls were non-stop back to back. Most days we wouldn't get a break or lunch due to queue and management would supplement that by brining over a piece of dry cold pizza that you wouldn't have a chance to scarf down. The supervisors are not supervisors. There are so many agents that we were broke into different 'teams'. You couldn't ask a coach for help if you weren't on their team. They weren't crosstrained on products and would give conflicting information that would often result in a failed AQE for us. \n\nDont use Innerthrive (will cause testicular cancer) , Keranique (once you stop using the menoxidel treatment your hair will fall out and will NO regrow), Enduros (just a bullshit product), Adams Flea and Tick (awful for pets, please avoid!), Athletic Greens (for green juices to be effective they must be fresh daily). \n\nI quit a few months ago for reasons unrelated to the shit job itself but I still get messages from managers asking me to come back but after 3 years of hell, no way!\n", "Tldr: bought supplement online for 120$ and manny pacquiao did not refund me. \n\nThis wasn't a weird trick but I wanted to start taking the Acai berry supplement. I thought I could get it online cheaper which I did but.... What the company didn't tell me (which was located in the Philippines but I didn't realize this until I called for a refund) was that there would be a recurring monthly fee. So basically, I paid 30$ for 100 pills I think and then the next month BOOM 80$ charge on statement and a bottle of 30 pills. \n\nI called the company and found out that I apparently verbally agreed to this. So here I was stuck with 80$ and pills. They told me to send the pills back within 30 days which I did. I called them back over a 6 month period and never got a credit. \n\nMoral of the story? Go to a drug store or a reputable website. \n\n", "I can shed some light on this for you. I work in internet marketing, and we deal with a lot of these offers. We call them rebills. I think you'd be surprised to learn that quite a large number of people are satisfied with these products whether they work or not. They aren't necessarily scams. They usually do some portion of what they claim to do, but not nearly to the extent they claim to do it. Garcinia Cambogia for example absolutely works for controlling your appetite, but it doesn't magically remove fat. Also many of the skin care products are legitimate products that work, but are overpriced with the subscription model. I can personally attest that many many many many many thousands of people sign up for these trials every day. A LOT of people do this knowingly, while some do not read the terms and conditions. In the world of CPA performance marketing these things are gold. In our case, between 50-90% of people will resubscribe for 2 months or more. If you have any more questions I will try to answer them, but I cannot disclose my employer.", "One of the guys I work with.\n\nWe regularly have to talk him down from going to cash checks for strangers from Craigslist or participating in MLM's. He's a strong combination of stupid and **REALLY** nice... he's the dude who's pulling over for strangers in negative degree weather to help change their tire. He just REALLY wants to make money any way he can, his parents are wealthy and he isn't and wants to live at the standard he grew up with, but without going to college, or working 40 years in a government job and retiring.\n", "Happened to me. I was wasted one night a few years back and feeling particularly chubby. I saw one of these ads for a weight loss pill and made a drunken resolution. The pills came and were not effective (I was actually eating healthy with them). Two weeks later, someone tried to use my card to make online purchases to an outdoor/adventure supply company for some snowboard equipment. It was a card that I hadn't used in a couple of months so I'm certain it was the company or person that I got the diet pills from.\n\ntl; dr: got scammed", "They are deliberately bad so they only are only clicked by idiots and old people. My grandma almost bought one of those fake browser antivirus things and I hate people who take advantage of the ignorant like that. ", "my grandmother, who spent $600 on face cream", "What about those ads on pornsites that claim to have sexy singles in your area willing to fuck for free?", "I read somewhere that scammers intentionally create ads like this, phishing emails etc, to weed out only the truly stupid people. They want normal people to be able to tell its a scam, so that the really only get the stupidest of the stupidest, to milk more and more money out of them down the road. ", "They piss off A LOT of doctors/teachers/ect...", "I worked cs a few months for a scummy company in Florida that sells a cosmetic treatment for making your abdomen flatter, and they claim 'it works'. first off, they don't let the cs reps try the product, a big red flag. One must buy a $30+ monthly subscription to the product if one wants to try it. Customers are encouraged to become 'dealers' so they can get the product cheaper. those dealers usually sign up their parents and grandparents for a monthly subscription. the elderly call and say they were tricked into subscribing. I was trained to never refund anyone. We would only cancel that subscription after three months of their paying for it, per the 'contract' they signed. The owners are proud to tell you they are born-again Christians. ", "I would say people who have never seen them before. The very first time I saw one I clicked on it. I became very frustrated after a few minutes because I never got to the information I believed I would find. Luckily I was very young and had no information, like a cc number, to accidentally divulge" ] }
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[ [], [ "http://www.slate.com/articles/business/moneybox/2013/07/how_one_weird_trick_conquered_the_internet_what_happens_when_you_click_on.html" ], [], [], [], [], [], [], [], [], [], [], [], [], [ "http://www.today.com/money/con-artist-took-359-million-bogus-free-trial-offers-174099" ], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [] ]
c8l9b7
where is your dna, and can it be changed by receiving donated blood or organs?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/c8l9b7/eli5_where_is_your_dna_and_can_it_be_changed_by/
{ "a_id": [ "esnno83", "esno1tn", "esno2ji", "esnof03" ], "score": [ 8, 3, 2, 2 ], "text": [ "It's in every single cell in your body. It can not be changed, as every cell would have to be changed.\n\nDonated organs and blood have a different DNA but are accepted in your body. They can't change what \"your DNA\" is though.\n\nDNA can be altered in single cells through chemicals or radiation. This means we can modify the DNA of a single cell that turns into a whole human (a fertilized egg).\n\nIf you change the DNA of a cell in a living human you have a chance to end up with a cancer cell.", "Every single cell in your body with the exception of red blood cells and platelets has an entire copy of your genome in its nucleus. That's what DNA is. It's not one thing in a single location. It's trillions of copies of the same thing in nearly every cell in your body. If you receive a donor organ, that organ will have the DNA of the donor, but it doesn't change any DNA in the rest of your cells. Likewise, blood cells, with the exception of white blood cells, don't have DNA, and white blood cells don't reproduce, so no, a blood transfusion does not give you new DNA. Blood is produced in the bone marrow, so if you receive a bone marrow transplant, the white blood cells you produce from then on will have the DNA of the donor, but again, that doesn't change the DNA of other cells in your body,", "DNA is contained in almost every cell in your body (there are some cells, like red blood cells, that lack DNA). Each of these cells has its own copies. \n\nWhen you receive a donor organ, you receive an organ whose cells contain someone else's DNA. It doesn't change the DNA in your own cells. \n\nThink of DNA as personalised instructions telling each cell what to do. Your own cells' instructions are written in your own way - your own handwriting, your own choice of words. If you receive a donor organ, those cells have essentially the same instructions but in a different form - different handwriting, different writing style, etc. No instructions are *changed*; you simply now have two different versions present in your body.", "Your DNA is in (almost) ever single cell of your body.\n\nIf you get a transplant of something made of cells you also get the DNA in those cells.\n\nRed blood cells, which make up much of your blood, are actually special cells that have removed most of the stuff that is in normal cells to make room for oxygen carrying haemoglobin, they have no nucleus which is where cells keep most of their DNA.\n\nThere are however other types of cells in your blood that carry the full amount of DNA.\n\nIf you receive an organ transplant, the cells in it will keep reproducing with their own foreign DNA. In case of Bone marrow which produces blood cells you even end up getting cells with foreign DNA outside the transplanted organ.\n\nAfter a transplant you essentially become a chimera with cells with two different DNA blueprints in the same body." ] }
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5li5dj
what is the pixel resolution of regular eyesight and what minimum resolution would be needed for vr glasses to match a normal person's vision?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5li5dj/eli5_what_is_the_pixel_resolution_of_regular/
{ "a_id": [ "dbvvbzc", "dbwiqrg" ], "score": [ 3, 2 ], "text": [ "Regular eyesight has a resolution equivalent to around __576 megapixels.__ This is the resolution that must be matched in order for VR to appear 100% real. (Although lower resolutions might suffice, too.)", "_URL_0_\n\nThe comparison has a major problem: manufactured CCD chips or manufactured films have regularity to their density. Eyeballs do not: the peripheral of the ovoid-projection-region to pick up light with cone-receptors and rod-receptors is lower density than the center of line of vision for each eye. We just don't build that kind of imperfection into cameras.\n\nEvolved eyeballs actually benefit, over-all, from the least complexity and least perfection that still gets the job done so that's how it turned out: better pixel density in the center of vision. Detail apparently isn't as important at the edges as long as other features are quickly detected about patterns, motion, luminosity, etc., so we avoid getting killed by weapons, snakes, bugs, falls, etc." ] }
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[ [], [ "http://www.gizmodo.com.au/2014/03/what-is-the-resolution-of-the-human-eye/" ] ]
2jggy8
why are our eyes not equipped to handle the sun's glare?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2jggy8/eli5_why_are_our_eyes_not_equipped_to_handle_the/
{ "a_id": [ "clbh44f", "clbhdrb", "clbhuu0", "clbi8hj", "clboo6b", "clbrxrf" ], "score": [ 6, 9, 3, 4, 2, 2 ], "text": [ "Evolution did not favor animals that stared at the sun in favor of looking for prey/predators.", "There is near-zero evolution value of staring into the suns glare. \n\n", "Also, I'd there is an adaptation: your eyelids and the instinct to look away.", "I would say we are. When it's too bright we squint our eyes. And it's pretty much impossible to stare at the sun without your eyes resisting opening. ", "It is an evolutionary trait that we have in order to regulate our exposure to the sun. Our eyes are the main way to tell how much light we are being exposed to and regulates how much vitamin D our bodies produce. MOst of us were not meant to spend eight hours on the beach in direct sunlight and if you have ever gone to the beach without sunglasses have you noticed that you feel more exhausted?\nThere is a down side to wearing sunglasses as well. If you do then you are not letting your body get a sense of how much vitamin D you need to produce. I haven't done extensive testing but from what I could tell between my brothers and myself, they would burn easier than I would (they wore sun glasses and I wear regular glasses)\n\nSurvival of the Sickest: The Surprising Connections Between Disease and Longevity \n_URL_0_", "The Arc LS Premium is rated at 22-25 lumens. The \"Nightsun\", the searchlight they use on military helicopters, is 50,000 lumens. The UltraFire 3x T6 produced \"a record 65,000 lumens\". (Like any record, they only last for so long so it may have been broken.)\n\nThe Sun puts out 6,840,000,000,000,000,000,000,000,000 lumens. Such a big number it might as well be gibberish. In this case it's six octillion, eight hundred forty septillion lumens. And don't forget that's 360 degrees of illumination and we're at a distance of 93 million miles.\n\nThe most powerful human light ever is probably the Texas Petawatt Laser at the University of Texas. It can put out laser pulses with more than 1 petawatt of power. A petawatt is 1 million billion watts, and writing it out in lumens is just an exercise in absurdity. But trust me, it's probably the brightest light known to mankind (including the sun itself). The sun puts out 1368 watts per square meter (again, from 93 million miles away). The Petawatt Laser can only focus its beam on a spot one-tenth the width of a human hair, for just one-tenth of a trillionth of a second, at a distance of like maybe a meter.\n\nThe ability to look at the sun without shielding would require protective adaptations that would essentially blind us any time we *weren't* looking directly at the sun. Imagine trying to live your life with a welding mask on all the time. Now humans (and quite a few other animals) do have some adaptations to help us deal with the sun's glare in relative terms. Our overhanging brows are basically a natural visor. The ability to squint and reduce the amount of light entering our eyes while still retaining the ability to focus. The most simple ability, to just look away by moving our eyes or our head. All of this helps us focus on things much more essential (like the last apple left on a tree) instead of an unshielded nuclear fusion reactor in the sky." ] }
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[ [], [], [], [], [ "http://en.wikipedia.org/wiki/Survival_of_the_Sickest_(book)" ], [] ]
7sx3rz
why aren’t planes designed to have enough overhead space to accommodate all passengers?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/7sx3rz/eli5_why_arent_planes_designed_to_have_enough/
{ "a_id": [ "dt82u6p", "dt82wai", "dt86olm", "dt87eru" ], "score": [ 18, 3, 3, 3 ], "text": [ "They would, except everyone insists on carrying bags on the plane instead of checking them, because checking them now costs money. Years ago, checking bags was usually free, and there was a lot more room in the overheads. Have you ever flown Southwest? Checked bags are free, and there's plenty of overhead bin room.", "Well, first off, most planes were designed and built before airlines started charging for checked baggage. Prior to that, overhead bin space was not a problem at all. It is very expensive to retrofit a plane, so very few have had significant work done since this policy change the need for overhead bin space.\n\nAt a higher level, though, there is no reason for them to do so. Adding overhead bin space is harder than it seems - you'd either have to have the bins be longer (which wouldn't help much and would make them more difficult to use) or reduce the number of passengers the plane could hold (which would reduce revenues). Neither of those provide a benefit _to the airline_ and unless you are choosing your airline based on overhead bin capacity (no one does) then improving this aspect of the experience doesn't increase revenues.\n\nBusinesses will only make changes based on what makes them more profitable. People don't think about overhead bin space when they book a ticket, so there is no incentive for the airlines to care about it either.", "Airlines have started cramming in more rows of seats than the same planes had in the past (by stealing leg room from each row), and airlines have begun charging for checked bags. These two factors mean that there are both more people on the plane and more carry-on luggage than there would have been in the past.", "* there are more seats in planes then there used to be\n* airlines often charge for checked bags now, so people have a greater incentive to only have carry-on\n* airlines mostly care about business travelers first, and most of them have frequent flyer status that lets them board earlier...only the tourists in the back usually wind up checking bags" ] }
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52680c
how much warmer would we feel if we didn't sweat?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/52680c/eli5_how_much_warmer_would_we_feel_if_we_didnt/
{ "a_id": [ "d7hpcpf" ], "score": [ 2 ], "text": [ "If we didn't sweat we'd be like dogs...our method of cooling ourselves down would be extravagantly panting in an effort to cool ourselves. This is less efficient than sweating so we'd be hotter for longer. " ] }
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apd011
nexplanon iud. how does it slow release the birth control hormones for 5 years?
I understand extended release pills and such, but how does the mechanism for Nexplanon (fka Implanon) work? It's not powered in any way and five years is a long time for something to be consumed by the body. Thanks in advance!
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/apd011/eli5_nexplanon_iud_how_does_it_slow_release_the/
{ "a_id": [ "eg7heu1", "eg7i4pa" ], "score": [ 3, 8 ], "text": [ "The way I understood it is like your body just really slowly absorbs the hormones out of it, the material is just thick enough to hold in the hormones but release a little i suppose? my doctor didnt explain it very well but also Id like to add, im pretty sure its only approved for 3 years, at least thats when I have to get mine changed. also, might be better to try r/Nexplanon ", "First off, Nexplanon is an implant. It's not an IUD because IUD means intrauterine device and goes in your uterus whereas this goes in your arm. The contraceptive implant was invented by [Sheldon Segal and Horacio Croxatto.](_URL_0_)\n\nThe implant outside layer are tubes are made out of silicone, which the body can't dissolve. in the middle of a tube, the hormone (progestin) is mixed into a slowly dissolving polymer. There is also a membrane that covers it. Water can get in, but the membrane slows how fast the drug can leave. By tweaking the surface area, the solubility of the polymer, the concentration of the drug in the polymer, and the diffusion rate of the membrane, you can control how fast the drug is released into the system.\n\nSo think about the Grand Canyon. Water flows through it and slowly erodes the rock and carries it to the sea. Erosion can be where water physically moves the rock, or it can be chemical erosion where something like salt is dissolved into the water and carried away. In the case of the implant, it's chemical erosion and it takes 5 years for it to be fully dissolved.\n\n[Here's a paper if you want more details.](_URL_1_)" ] }
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[ [], [ "https://en.wikipedia.org/wiki/Sheldon_Segal", "https://watermark.silverchair.com/56-3-739.pdf?token=AQECAHi208BE49Ooan9kkhW_Ercy7Dm3ZL_9Cf3qfKAc485ysgAAAkMwggI_BgkqhkiG9w0BBwagggIwMIICLAIBADCCAiUGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQMWEFXUzPV8iwZFPF3AgEQgIIB9tP3ML05riWH5ZfAMLbNpzENAI1IWbvhhsDBdcZ7DLzUqctcAZEWHTT2p-d-CtvfZBbDvlS39WlziawBlENX7_Cy-mjRol4JytZ25WDFzPIleLC7PjNI0Zj4n2O1m25gWTnK1cDzRORun7-PjIR2DM2e_uTbChkgySMKRg46Q-C0qr6s0YnMxp3UEsGvW1ZMglMJrQzSCRWGMeIYWG5xzvULdv-s1a-8q2SzmQtO6hm5kxLan1ssXagGQEGbPwYEuPQ6s0krCHu0VLuPBYQmwAS5bPcec7KxBqUTY_GsO8VOJqrN2MiAJgCgf64-4uVUhGXT_S8Wh7hUn93tei1zUPXCHw458JbSg2z0d82UyXz1Apk2RSAAIOd1Dhcd1S_dEjhXEDVQTL8WMqOUMcB6v78Mtjm-dvOebbUARGVmEeu5OY3qWOx5eF3hcqanG6BdL8AM2ppt5cdSyEJQfpTSJEWFjRR71g9mxBePtYN5FZR6dkqWZiSqbQk8MYCSpZgQ5ySJALOXz3cThU5cpBXvU0AWSFsuXSaB6rjP6Glzbw99oRLK470g4Zy5rTnb9n-b0QmMYE9OWhY6u7-9YjzOEiK9-sW1fXNdp5wwg4fr3RT-S2-sz7yW_oFRiTqayyiAVQ9HmmjWPhBZ3de6z537qSEUmoXXcvQ" ] ]
1jdqgn
why does light appear to warp around objects when held close to your eye?
One of the easiest ways to see what I am talking about is to hold your finger a couple of inches in front of one eye, close the other, and move your finger up and down slowly.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1jdqgn/eli5_why_does_light_appear_to_warp_around_objects/
{ "a_id": [ "cbdnc58" ], "score": [ 2 ], "text": [ "Your vision field has a blind spot right between your eyes that your brain makes up for. Putting something there that blocks light doesn't make sense to the brain, so light 'bends around it'.\n\n" ] }
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26igsg
why do i feel all shaky after a hot bath?
It feels like low blood sugar. Happens every time.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/26igsg/eli5_why_do_i_feel_all_shaky_after_a_hot_bath/
{ "a_id": [ "chrd7dh" ], "score": [ 3 ], "text": [ "Low/High bloodpressure. Not sure which but i get it too, combination of the heat and standing up fast. Ive blacked out after baths before." ] }
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5c4o08
with the abundance of scientific information at ones fingertips, how does one believe in creationism?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5c4o08/eli5_with_the_abundance_of_scientific_information/
{ "a_id": [ "d9tlox4" ], "score": [ 2 ], "text": [ "Creationism isn't a scientific theory. It is religious dogma. People who believe it are often raised from birth to believe it, and are threatened with ostracization from their social group and even their own families if they believe otherwise, and threatened with the idea that they will receive an afterlife of eternal torment and suffering in hell for disobeying their god. \n\nThese people don't care what scientists say, or what \"the facts\" are. Scientists and facts don't save you from everyone you know abandoning you. They don't save you from cosmic punishment. " ] }
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2gv60x
why do businesses seem to be stingy with ten-dollar bills?
It's like they're coveted, and everyone seems to either give away as little as possible or simply refuse to distribute them at all. Why?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2gv60x/eli5_why_do_businesses_seem_to_be_stingy_with/
{ "a_id": [ "ckmspqs", "ckmt3wu", "ckmtbl0", "ckmtp1m", "ckmvh3k" ], "score": [ 6, 11, 5, 3, 2 ], "text": [ "For most of the business I've worked for, the registers wouldn't have any ten dollar bills in them at the start of the day. Still not quite certain why, but it was just always how it was. So, quite often, it wasn't that we were hoarding all the ten dollar bills. It's just that there were none to be given at all. ", "Often they have few if any to give. The thing is, fives are more versatile since they can break tens or twenties, but tens can only break twenties or higher. Higher than twenties the next up is fifty or a hundred, so youre better off breaking with twenties and fives (2 20s and 2 5s = 50. 5 20s = 100). Considering most bills arent going to need flat fifty as change, but say, 47.73 or so (who the fuck buys a large mocha with a 50? Assholes, thats who), stocking tens doesnt really make sense. When the registers are stocked after drawers are counted, those are the bills they get. Most or all tens they get came from customers,.", "I worked cash control, and at the store that I was at, 10 dollar bills were always losers. By this, I mean that if we started the day with $10000 in 10's, we'd end the day with $7000 in 10's. Every few days we'd have to buy a couple straps from our bank and have them delivered. \n\nWe never discouraged our cashiers from giving out 10's, but I could see where a smaller business would run out pretty fast, especially if they can't keep a lot of cash on site for safety reasons. If you've only got 50 10's in the safe, then you don't really want to give them all out too fast, because getting more might be a pain in the ass.", "$10s are versatile, and the cashier doesn't get very many of them.\n\nPeople frequently pay with $20 bills for small purchases, which can quickly deplete $5 bills in the absence of $10s. Depletion of $5s is a good way to start running through huge stacks of $1s, and have upset customers who don't like a large number of small bills. So hoarding $10s and only using them to \"protect the fives\" is somewhat necessary for stores that don't get a large enough volume of cash coming through to reliably replenish the fives or pretty much anywhere in the morning.\n\nAt a typical medium to high volume convenience store, people pay with $20 for small purchases like coffee and a breakfast sandwich *all the time* in the morning, then the lunch rush gives more 5s and 10s than in the morning. The effect is more pronounced on Monday and Tuesday than later in the week. I worked at one for 7 years and this pattern almost always holds! I guess people carry bigger bills from payday/weekends and then collect smaller ones from change to use later.\n\n10s also, in a pinch, can be used as change for larger bills (50s and 100s) without giving the customer a ton of bills back. But mostly stores hang onto them when they can so they can slow down how fast they blow through 5s, which can fly away very, very quickly, especially on a busy morning shift. At least that's how it was where I worked. Holding 10s until you really need them can help avoid weird change situations later.", "In the service industry where there is tipping, the server might give you a 5 and five 1's to make sure you have the correct change to leave the tip. " ] }
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51ma3f
how come when my foot falls asleep while sitting down, standing up makes the sensation go away for a few seconds, and then it comes back even more intensely?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/51ma3f/eli5_how_come_when_my_foot_falls_asleep_while/
{ "a_id": [ "d7d233n" ], "score": [ 2 ], "text": [ "A limb falling asleep is due to the sensory nerve getting pinched, preventing the nerve signals from reaching your brain. When you stand up and remove the pinch, it takes a moment for the backlog of signals in the nerve to clear and for it to resume normal function. That's why you often get a rush of pain as an asleep limb wakes up; there's a whole tangle of impulses that need to be resolved. " ] }
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6041cv
why do we get this weird pain in our throat every time we are in an uncomfortable situation?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6041cv/eli5_why_do_we_get_this_weird_pain_in_our_throat/
{ "a_id": [ "df3c3d4" ], "score": [ 16 ], "text": [ "That is known as \"Globus Hystericus\" or, a sensation of a lump in your throat as a response to an anxiety provoking situation. \n\nCommon emotional response. Not everyone gets it. \n\nNote: if you are having constant difficulty swallowing, please see a doctor \n\nEdit: correction " ] }
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esljon
why does putting a heavy book on a a crumbled piece of paper make it flatten out and why does it take 10-15 mins for it to happen; not instantaneously?
[deleted]
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/esljon/elif_why_does_putting_a_heavy_book_on_a_a/
{ "a_id": [ "ffbbahf", "ffc8t1o" ], "score": [ 3, 3 ], "text": [ "Educated guess; the fibers were massively mis-aligned and set out of order when the paper was crumpled, and setting a weight on top of it makes new small “folds” in that fibrous structure that aligns the whole crumpled mess to all fit in that small space, the space between the two surfaces you’re pressing together. I imagine it might actually take some time for the fibers to move into place, not for them to resettle/harden once they are in place.", "The heavy book puts a force on the paper that is uniform but not directly opposite the original force that formed the various folds. \n\nThe result is a flat-ish piece of paper but the time required to straighten it out is longer than if you took the paper and folded it the opposite way. The issue is with a crumpled piece of paper going exactly opposite isn’t usually feasible. \n\nThe book adds a force that is reciprocated by the hard object (table) on the other side of the paper and over time “unfolds” the paper. If the book is heavier in general it will take less time as the work done on the paper is a factor of force and time (generalized)\n\nAlso my apologies because no 5 year old would understand my answer..." ] }
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dk12fx
what's happening in chile right now?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/dk12fx/eli5_whats_happening_in_chile_right_now/
{ "a_id": [ "f49r32z", "f49rea1" ], "score": [ 3, 2 ], "text": [ "Copied from another comment I made\n\"They have been upping the price of everything, water, electricity, gas and this is for no reason, the service is still horrible during peak hours and almost impossible to use, our minimum wage is like 410 usd and the monthly transportation cost is like 70-80 usd (2 trips per day, 5 days a week) so yes, we're tired and while this was happening our president was having pizza in a rich area lol, people were just evading the metro but they ended up closing entire lines (during peak hour) to stop people while having hundreds of armed policeman (They say they lack personnel, which is why poor areas doesn't have many police people around) in the doors of the stations, so yes, we're fucking fuming and I hope we burnt everything, this place is a fucking shithole and something needs to be done (Also they have shot at kids during all of these, there is a rumour that one underage student died because of a \"bullet\" in the neck)\" also the corruption is awful nowadays, every big institution in this country has been found guilty of something while having no repercussions (some guys made a 1.4mil usd fraud and all they got was ethical classes, no jailtime for anyone)", "Chaos and violence erupted last night with people burning subway stations and other buildings and looting some stores in Santiago, Chile's capital.\n\nHow did this start: the government announced a new increase of the public transport fare. The increase itself is not much, but people saw it as 'one more unfair thing' in a series of problems that the working class faces, that the government has been unwilling or unable to address.\n\nTo protest the fare increase, students started to run 'en masse' into the subway stations and jumping over the payment tourniquet. They called it \"evasión masiva\" (massive evasion) of paying the fare. This lasted for 2 days, and had popular support as a way of protesting. \n\nThe government's response was to send police to guard subway stations and detain the students. Yesterday, other regular people joined the protests, and disrupted the operation of the subway by sitting on the edge of the platform. Others started destroying some of the stations. This caused the subway to eventually stop all operations, because they couldn't guarantee the safety of the passengers or the workers anymore. \n\nThe subway is a vital part of the transportation system in Santiago. Without it, thousands of people had to walk home, some for hours, and the protests moved from the subway to the street. \n\nThe governments response was to send more police to try to control the protests, and announce harsh consequences for the people involved in the disturbance, without ever addressing the fare increase issue.\n\nMeanwhile, the president was seen eating pizza at a restaurant in one of the nicer neighborhoods of the city.\n\nAll this caused increased anger and the violence got worse, now with the burning of the subway stations. This is a very terrible thing, most people like the subway and rely on it to move around the city, so most people do not agree with this.\n\nSince the police were unable to control the situation, the government declared state of emergency and call the military to the streets. And that's where we are now.\n\nCalling the military is a big deal, since it had not been done to deal with public unrest since Pinochet's dictatorship.\n\nWhat are the other issues people are angry about:\n\n- Pensions: the pensions system has been criticized, and there have been protests in the past few years, because the pensions people get are very low\n\n- Healthcare: you can go bankrupt trying to pay the hospital if you get some diseases that are not covered by regular insurance. Also, medication is very expensive. About 5 years ago we had a 'sick people protest' on the streets because of this. \n\n- Education: the public school system is underfunded, and the few public schools that are good can't take all the students that want to get in. Private schools can be very expensive. Students have been protesting since 2006 demanding changes here.\n\n- Inequality: half the workforce earns USD 562 or less a month. Most of the time this isn't enough to pay for everything and people are in debt." ] }
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diwvr4
how did the cia helping smuggle cocaine for the contra benefit the us?
[deleted]
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/diwvr4/eli5_how_did_the_cia_helping_smuggle_cocaine_for/
{ "a_id": [ "f3z9zaa" ], "score": [ 7 ], "text": [ "The US wants to give guns to Group C, without breaking any laws. There are laws against giving military weapons to Group C. So, the CIA finds some folks willing to commit crimes, let's call them Group D. The CIA says \"We will help Group D make more money if they give 75% of the extra profits to Group C. By the way, Group C wants their payment in guns\". Everybody is happy. The CIA didn't break any laws. Group D broke some more laws than they were breaking before, but they were criminals and criminals break laws - by definition." ] }
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2jxfdb
why are we so repulsed by sexual thoughts of our parents?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2jxfdb/eli5_why_are_we_so_repulsed_by_sexual_thoughts_of/
{ "a_id": [ "clfyxu2" ], "score": [ 2 ], "text": [ "Evolution. Incest leads to birth defects, so both biology and culture have long combined to make incest repulsive" ] }
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4kym3b
why did pol pot want to enforce an agrarian society?
I've been reading up on it and I don't get what he expected to achieve. Did he just really hate the people living in urban areas, since they weren't even taught how to actually farm properly? What was the point of 'starting again'?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4kym3b/eli5_why_did_pol_pot_want_to_enforce_an_agrarian/
{ "a_id": [ "d3iuaay", "d3ivak9" ], "score": [ 2, 5 ], "text": [ "There's a number of reasons that tin pot dictators want to enforce this type of thing:\n\n- People that are subsistence farmers aren't likely to be educated or ask a lot of questions if they're just trying to eke out a living (also the reasons that the first to be shot during the revolution are intellectuals, political opponents and teachers).\n\n- Means your country can technically survive w/o starving if your neighbours bring in a blockade or embargo (though this can turn to shit if you have a famine or drought, as in North Korea).\n\n- The whole \"agrarian society\" is a hallmark ideal of socialism and communism. The image of the farmer is the classic one presented as the worker or proletariat, and the first thing Stalin did was to reorganise the countryside into collective farms with production quotas and Five Year Plans.\n\n- Draws back to point #1, but uneducated, illiterate people with no access to outside information, education or the like aren't likely to get too many ideas about \"democracy\" or any other inconvenient subject matter.", "Pol Pot was aggressively anti-intellectual, possibly influenced by his abject failure at university (in Paris). Under his control, the Khmer Rouge targeted anyone who associated with \"Western\" intellectuals in any form. He considered urbanism a \"Western\" trait, and ordered the complete evacuation of Phnom Penh, sending those who weren't executed back in to rural farm co-ops. \n\nSince religions could influence the behaviour of the people, that had to go too, along with anything not fitting the plan. The intellectual justification for this was called \"Year Zero\", the idea that it was necessary to completely break society down all the way, before building it back up in the revolutionary image. " ] }
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3ne5at
why don't people feel the urge to swallow gum?
Since most pieces of gum are bite sized, it seems like something that people would swallow more frequently. Are we just trained not to swallow it? That's why people are more reluctant to swallow gum? Because I have to try to force gum down.
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3ne5at/eli5_why_dont_people_feel_the_urge_to_swallow_gum/
{ "a_id": [ "cvn76bf", "cvn7n64", "cvn7qmj", "cvn9mvh" ], "score": [ 16, 2, 14, 2 ], "text": [ "Yes, we are pretty much trained not to swallow gum. If you give young children gum, they will swallow it. They need to learn not to swallow it. And eventually the idea of not swallowing gum becomes so integrated in your mind, that you start finding it hard to because you are going against everything you learned.", "Think about the consistency of gum vs. food that you've chewed enough to swallow. The gum is probably denser and not as squishy. I have this weird fear that if I were to swallow gum I would choke on it somehow.", "I subconsciously swallow almost every piece of gum i am done with so i guess i am just different. ", "how the fuck is this the top of my front page?" ] }
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4ekqb6
doctor strange and his role in the rest of the marvel cinematic universe
Just saw the trailer and I'm getting some multiverse vibes. Is this true? If so, how is he different from the rest of the MCU characters?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4ekqb6/eli5_doctor_strange_and_his_role_in_the_rest_of/
{ "a_id": [ "d20y5pr" ], "score": [ 8 ], "text": [ "He's the \"bridge\" into the magical realm. So far, the Marvel movies have only touched on magic. Most of the magical heroes i.e. Thor, Scarlet Witch have had their powers explained by science. \n\nDoctor Strange is going to be actual monsters and magic. This'll hopefully lead into movies such as Ghost Rider and Moon Knight (Netflix?) where magic is more of a factor. \n\nDoctor Strange will travel into the \"astral plane\", so like a dream world. Not sure yet whether they'll introduce the multiverse in terms of alternate realities for example: Where heroes are villains and villains are heroes, or where the Avengers died in the battle of New York. They might save that for post-infinity war." ] }
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4a94nb
why are dogs' ears all floppy when they're puppies but stiffen up when they're adults?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4a94nb/eli5_why_are_dogs_ears_all_floppy_when_theyre/
{ "a_id": [ "d0ydy2h", "d0yezzn", "d0ytdws" ], "score": [ 303, 41, 3 ], "text": [ "The reason why ears are floppy in pups and erect as adults (in those prick eared breeds) is because the ear cartilage is soft and not fully formed. The cartilage doesn't start to harden or set until 16 weeks or so which is why their ears can be up one day or opposite ears over a few days etc. \nNow as for those that are cropped, the minor surgery is performed no younger than 8 weeks and no older than 16 weeks as it needs to be soft in order to get the ideal shape and they be fully erect by the time they finish teething. ", "Babies have floppy ears also. It's like the car wash. Anything that could get broken off or damaged going through the tunnel is soft so it won't get damaged. You should feel human baby ears. Sometimes you have to tape them because they're rolled up or folded. Then like a small puppy they harden.", "Great story on why domesticated dogs have floppy ears. _URL_0_" ] }
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[ [], [], [ "http://www.radiolab.org/story/91696-new-nice/" ] ]
27ne3h
why/how did animals and plants evolve so differently?
Why did plants and animals evolve so differently? Didn't they come from the same basis of "life". If we share a common basis, and I believe, common DNA, why have plants not achieved a central nervous system or brain?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/27ne3h/eli5_whyhow_did_animals_and_plants_evolve_so/
{ "a_id": [ "ci2hgyi" ], "score": [ 3 ], "text": [ "Because you're assuming that a brain or central nervous system is a milestone for evolution. It isn't. Evolution only cares about what can survive. Plants can survive, thus they still exist. Plants don't need brains for this, thus they don't spend resources on brains.\n\nPlants evolved to harness the power of sunlight to convert CO2 into oxygen and sugars. Animals evolved later to harness the power of oxygen to convert sugars into energy. " ] }
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3kc7bb
what is this item?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3kc7bb/eli5_what_is_this_item/
{ "a_id": [ "cuwd8nx", "cuwdfda" ], "score": [ 3, 12 ], "text": [ "I can't think of the name of it but it looks like one of those things a \"pharmacist\" would use to crush pills or whatever", "Old fashioned [pestle](_URL_0_). Probably brass. Used for grinding herbs and whatnot. See picture for similar item." ] }
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[ [], [ "https://www.etsy.com/listing/150023452/mortar-and-pestle-vintage-brass-old" ] ]
rhtkh
the music industry. (more specific questions in comments.)
-Who really decides what is on the radio? -How do artists choose what will be their singles? (What exactly are "singles" anyway?) -Do artists know that half of their album is filler? Do they know which songs will be hits? -The whole "top 100" thing. Who decides that?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/rhtkh/eli5_the_music_industry_more_specific_questions/
{ "a_id": [ "c45zu9m" ], "score": [ 2 ], "text": [ "[Here](_URL_0_) is info on the Top 100. It's basically a calculation based off of times a song is played on the radio and sales. Billboard Magazine publishes the rankings. " ] }
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[ [ "http://en.wikipedia.org/wiki/Billboard_Hot_100" ] ]
2ti629
how can i tell the difference between a star and a satellite with my naked eye when looking at the night sky?
Everything is just so shiny up there. It's hard to tell what's what with the naked eye. Am I the only one?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2ti629/eli5_how_can_i_tell_the_difference_between_a_star/
{ "a_id": [ "cnz9i30" ], "score": [ 4 ], "text": [ "Here's a quick guide:\n\nSatellites move - quickly enough that you can easily see them moving.\n\nStars twinkle (because the atmosphere distorts what are point sources of light, making them appear to twinkle).\n\nPlanets don't twinkle (they're big enough and close enough that the atmospheric distortion doesn't have much of an effect)." ] }
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5mzcr9
how scenes of animal movies are made?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5mzcr9/eli5_how_scenes_of_animal_movies_are_made/
{ "a_id": [ "dc7lpgz" ], "score": [ 2 ], "text": [ "Three ways:\n\n1) They raise an animal with a professional trainer to appear in movies. Sometimes they have animals on hand for general-purpose Hollywood stuff, and sometimes they raise an animal from scratch specifically to appear in a certain role.\n\n2) They use puppets and animatronics, especially if the scene is dangerous or depicts the animal getting injured.\n\n3) They use CGI. Very common nowadays. Even animals just standing around in the background (like a herd of sheep, for example) are rendered in CGI because it is cheaper than actually trying to have them on set." ] }
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6kci64
why do toilets not have an overflow secondary drain as sinks do?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6kci64/eli5_why_do_toilets_not_have_an_overflow/
{ "a_id": [ "djkztpy", "djl0og9", "djl2uxf", "djl3a5a", "djl3wyu" ], "score": [ 116, 26, 8, 2, 3 ], "text": [ "There's still just one drain for a sink. The overflow is just getting water to the route it would if the drain wasn't plugged.\n\nFor a toilet, if the drain is plugged the flow of water is going to be stopped (or slowed) entirely. An overflow drain would end up just as backed up.", "Apparently, overflow-proof toilets already exist. [Sauce](_URL_0_). As a justification, sinks and bathtubs are designed to be plugged purposefully, and the overflow drain prevents this intentional blockage from causing a mess. In contrast, a toilet is not designed to be intentionally plugged.\n\nEDIT: There's also already an overflow-sensing shutoff system. [Sores](_URL_1_)", "This is a good question.... A secondary pipe that is ran alongside the main toilet drain or even molded onto the side of the entire pipe would solve this issue. Problem is if toilet paper were to get into the smaller overflow drain unclogging that might be a bit harder. But having a backup would be the best thing... Source? My child flooded my fucking bathroom tonight......", "The idea of having a overflow channel is a good idea. Most of the older style toilets get plugged in the start of the s shape. The overflow channel could drain behind the usual location of the blockage.\n\nOne note though, the new toilet design is WAY better and gets blocked far less.", "Toilets are different than sinks in that they have an integral trap in them. You can usually see how what you flush has to go up and then down the drain. Having an overflow for a toilet would bypass this trap, and nasty sewer gas would come out all the time. \n\nSinks have a separate trap installed underneath them. The overflow uses the same piping as the main drain, but is really only meant to be used if the stopper gets left in accidentally. If you have a clog, it will still flood. " ] }
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[ [], [ "http://www.penguintoilets.com/", "http://aquaone.com/wp-content/uploads/2012/01/Toilet-Guardian-Specifications-Sheet.pdf" ], [], [], [] ]
3ibmh8
why/how does my nose bleed when the weather is dry?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3ibmh8/eli5_whyhow_does_my_nose_bleed_when_the_weather/
{ "a_id": [ "cueyol7" ], "score": [ 3 ], "text": [ "The dry air creates cracks in the nasal membranes. The cracks crust over and become itchy and often bleed when itched or if the nose is blown too hard.\nTo prevent future nose bleeds due to dry air, I would recommend getting a humidifier for your house to help keep moisture in the air." ] }
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1ohxq6
how does reddit determine where to rank submissions?
How does reddit determine if a submission gets shown on the first page and how long it stays there?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1ohxq6/eli5how_does_reddit_determine_where_to_rank/
{ "a_id": [ "ccs3bs9" ], "score": [ 3 ], "text": [ "CGP Grey explains it nicely in his video 'What is Reddit?'. He uses the analogy that every post is a helium balloon and every upvote increases the amount of helium in the balloon and every down vote decreases the amount of helium in the balloon. Weights are added periodically so that older links don't stay on the 'hot' page forever, allowing newer links to have their turn." ] }
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3mik5u
the james "whitey" bulger case.
With all the popularity of the new movie Black Mass I was wondering more about the case. What was he accused of? What is the controversy with the FBI and Connelly? Why do so many family members of deceased victims feel animosity towards the government?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/3mik5u/eli5_the_james_whitey_bulger_case/
{ "a_id": [ "cvf88bx" ], "score": [ 3 ], "text": [ "Please watch the documentary \"Whitey.\" It is a very entertaining documentary.\n\nSpoilers: Whitey (allegedly) was being protected by the FBI. The FBI agents would get very nice gifts from him, and he did not even get arrested, assumedly \"in return\" for these gifts, at any point during his reign. People died and the FBI turned a blind eye. During his trial, some 30ish years later, he makes it clear that he:\n\n1. Was not an informat. Thus, he could go to prison (he was very old) while still having an honor in that he \"wasn't a rat.\" This also means that there was 100% no reason for the government to protect him (if he had been an informant, the government would have protected him to some degree in exchange for information).\n\n2. The government protected him in exchange for presents and gifts, thus, asserting massive corruption.\n\nSince the trial was about whether or not he did the crimes, the trial didn't really have a \"verdict\" on the government's involvement. He didn't pretend he didn't murder people and was put into jail for life. His guilt in the matter, though, has no baring on whether or not the FBI was protecting him.\n\nLocal family members believed that their friends and family that died at the hands of Whitey could possibly have been prevented if the FBI had even attempting to be doing their jobs.\n\nThe end of the documentary is incredible. Please watch it." ] }
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1j1r6h
do i contact my senators or my representatives or both to urge them to support bills?
Let's say that a Representative introduces a bill proposing free hot dogs for everyone on Memorial Day. That bill is called HR1234. Does it get voted on only by House members and the Senate has to introduce its own free hot dog bill, S1234? Or does it get voted on by just the House first, and if it passes, it goes to the Senate for a vote? Or does it get voted on by both houses at the same time? I need to know this so I know if I should only be emailing my Representative about HR bills & my Senators about S bills, or if I should be emailing all about both. Thank you in advance for your help in clearing this up for me.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1j1r6h/eli5_do_i_contact_my_senators_or_my/
{ "a_id": [ "cba7uk6" ], "score": [ 2 ], "text": [ "If the bill passes the chamber in which it was introduced, it goes to the other chamber. In the case you mention, you want to write to your representative first. If the bill passes, write to your Senator. If not, don't bother." ] }
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dud985
why is it dangerous to eat raw chicken or raw eggs, but you can eat rare steak, which is very bloody?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/dud985/eli5_why_is_it_dangerous_to_eat_raw_chicken_or/
{ "a_id": [ "f74hlj5" ], "score": [ 11 ], "text": [ "Chicken and eggs frequently have salmonella contamination. This is because chickens carry the bacteria, and in processing the meat, the bacteria naturally gets spread to the smaller pieces. \n\nBeef don't carry salmonella, but it can be picked up in the processing plant. Because beef is often eaten in larger pieces, the contamination from processing stays on the outside, and is killed with even slight cooking. However, ground beef, because of the smaller pieces, is much more easily contaminated, which is why people can [die from eating it. ](_URL_0_) It is still really important to keep kitchen utensils and your hands clean while preparing beef though." ] }
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[ [ "https://time.com/5716929/salmonella-outbreak-ground-beef/" ] ]
9k8gyo
where the fuck does wind start?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/9k8gyo/eli5_where_the_fuck_does_wind_start/
{ "a_id": [ "e6x4y8q" ], "score": [ 3 ], "text": [ "With hot air rising over parts of land heated by the sun and cold air falling down the sides of cold mountaintops." ] }
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c9ahws
why is there such a huge difference in intelligence in humans? isn’t our physical brain broadly comparable, and capable of the same performance in memory retention and retrieval, mathematical calculations, problem solving, etc.?
Do animals have the same degree of variance within a species?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/c9ahws/eli5_why_is_there_such_a_huge_difference_in/
{ "a_id": [ "esv27rf", "esv8h6s", "esv8hie", "esvyw8n" ], "score": [ 16, 10, 3, 4 ], "text": [ "If you think about the intelligence it takes to do basic tasks, like distinguishing colors and shapes or understanding a simple sequence of events, we’re all roughly as smart. The variation really becomes apparent for more sophisticated tasks like doing calculus or coming up with insights from large volumes of unconnected data. As tasks get more and more complex, differences in intelligence become more clear. So in a sense, we’re all roughly equal in intelligence compared to, say, dogs. But compared to a theoretical physicist, there is a huge variation because the underlying problems are so challenging.", "If you compare the tiniest dog breed with the largest dog breed, you'll see that there's obviously a massive difference in the sizes of dogs.\n\nIf you compare all dogs of all sizes to a tiny plankton and a massive blue whale, then all dogs look roughly the same size.\n\nThe reason there seems to be a huge difference in intelligence in humans is because your scale only runs from dumb humans to smart humans. The difference will always appear to be large if you zoom in like that. Compare humans to other sentient creatures, and suddenly we all look fairly similarly intelligent.", "Answer: I don't think anyone really knows yet.\n\nI read something a while back that suggested blood flow and good circulation in the brain affects intelligence, and plenty of articles out there say that your brain eats up 20-25% of your body's entire energy usage. This usage number is a lot lower in other primates, and lower still in other animals. There are arguments to be made that regular exercise helps learning and problem solving.\n\nIt then makes sense to say that differences in physiology from one human to the next can affect intelligence because of the effects mentioned above.\n\nBut there's also the \"nurture\" part of it. And motivation. One person may be really intelligence but has just no motivation. The question, then, is: why aren't two people with equal blood flow in the brain equally as intelligent? \"Motivation\" won't cover it.\n\nI think any pet owner who has had multiple pets of the same type (multiple dogs, etc.) can attest to the varying intelligence. Some dogs are easier to train. Some love running headlong into walls.", "The old quote:\n\nDon't judge a fish on it's ability to climb a tree.\n\nThere are people that would fail in a theoretical physics classroom, but could reproduce a piece of music after hearing it once, or mould a piece of metal from no more plans than the inside of their forehead." ] }
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pqxzf
why is fried food "bad for you"?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/pqxzf/eli5_why_is_fried_food_bad_for_you/
{ "a_id": [ "c3riwu0", "c3riz1c", "c3rjw89" ], "score": [ 2, 10, 6 ], "text": [ "The fat content of fried food is generally higher than food prepared other ways. Also, some types of oil used to fry food contain a lot of \"bad\" fat (e.g. trans fatty oils). \n\n(Note: there are oils with a lot of \"good\" fat, like olive oil, but olive oil can not be heated as hot as is required for some types of frying)", "To clarify on the others posts: It's high fat AND high carb. They also tend to hold little nutritional value, so even if they were low fat and/or low carb, you wouldn't gain much by eating them, aside from fulfilling a need for calories. \n\nSomething being high-fat on it's own doesn't make it bad for you, unless you eat a lot of carbs. ", "Most fried food nowadays is fried in either vegetable shortening (trans fat) or some sort of vegetable oil (soybean, canola) which are high in polyunsaturated fats, such as Omega-6. These are unstable and oxidize easily, creating inflammatory, mutagenic isomers which promote heart disease and cancer. \n\nAll fried foods absorb fat, but it is safer to fry them the old fashioned way: in lard or beef fat, which are stable under high heat and will not suffer this oxidative damage." ] }
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4097p6
how were countries like pakistan and india able to acquire nuclear weapons when far more prosperous countries like iran haven't been able to?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4097p6/eli5_how_were_countries_like_pakistan_and_india/
{ "a_id": [ "cysfebb", "cysffka", "cysjaoi", "cyskuhe", "cysmjxw", "cysmm76", "cysy5sh", "cysyboc", "cyt0nsp", "cyt19vg", "cyt8lez" ], "score": [ 266, 33, 4, 3, 2, 19, 4, 4, 5, 6, 3 ], "text": [ "I'm not sure why you think Iran is far more prosperous than India. The Gross Domestic Product of India dwarfs that of Iran several times over. India has the third largest GDP in terms of purchasing power parity in the world.\n\nSo India has nuclear weapons because they are simply powerful enough. Pakistan is believed to have nuclear weapons because they were given help by the ~~Russians~~ Chinese* to keep India's power in check. \n\nIn the early days of nuclear weapons development, Iran was not very prosperous at all. While it is prosperous enough now to potentially have a nuclear weapons program today, the West (mostly lead by Israel) has gone to great lengths to prevent Iranian nuclear weapon development.\n\n*edit: Thank you no_lungs for the correction.", "Without directly addressing Iran's particular situation, the acquisition of nuclear weapons is a political decision, not an economic one. Numerous countries which would be materially capable of independently developing nuclear weapons have not chosen to do so for political reasons, while certain others chose to expend substantial material resources to do so for their own political and military reasons.\n\nTo address the case of Iran, then, there are substantial complicated political reasons for the current state of affairs. Simply put, for Iran to outright admit an intention to develop a nuclear weapon capability would invite even more diplomatic problems than it already has, and as such any intentions which Iran may potentially have to that end must be publicly denied, and material efforts to that end either hidden or disguised as efforts toward non-military nuclear technology.", "The territory of Kashmir in the north between India and Pakistan has been disputed for decades, by the two countries. They both claim this territory belongs to them. Because of this disputed territory, India and Pakistan have basically been in a constant stand off for decades. Kind of a cold war so to speak. This is why India and Pakistan chose to develop nuclear weapons. They are pointed at each other.\n\n(_URL_0_)", "Maybe its about money, maybe its about politics, maybe its also about having more talented scientists. ", "I'm still baffled by the \"far more prosperous\" bit of this question. I've lived in an Indian city and believe me the money and the type of life the rich have there will amaze any one from the west. The total number of middle income families in India outnumber the entire number of people living in many developed countries. But as for the question, the Russians were the ones who helped India with their nuclear power while China helped Pakistan with theirs. Iran's instability in its political helm has kept the pressure by international government especially by Israel and their affiliation with US to keep their nuclear program in check. The recent deal systematically killed their capability of enriching uranium as a trade off for lift on economic sanctions. Which is a great deal since Iran can use those resources and make a more prosperous country...maybe equal to India someday lol ", "Pakistan got them via a guy called A Q Khan, who worked in Holland for a company who made parts for nuclear activities etc, he stole a load of info from the company, took it back to Pakistan, and used it to start Pakistan's nuclear programme. Once he had got the technology and know-how, He then sold it on (for personal profit) to Iran, DPRK, Libya and even tried selling it to Saddam Hussein (who didn't take the opportunity) the US knew He was pedalling this info but at the time were supporting the Taliban against the Russians in Afghanistan via Pakistan and didn't pursue Khan as they needed to keep Pakistan sweet.\nIran had all the other technology for nuclear activities but maintained their nuclear programme was entirely for civilian purposes. ", "What? Iran? Prosperous? lmfao...", "Pakistan and India didn't threaten to blow up Israel and the US with their non-existent nuclear stockpile before trying to develop the weapons like Iran did.\n\nClassic \"mouth is writing checks your body can't cash\" situation.", "OP. this will give you some perspective.\n\n_URL_0_", "Iran, more prosperous than India... the ignorance about Indians on this sub and /r/worldnews never surprises me...", "I heard that Saudi Arabia paid billions to Pakistan to develop nuclear weapons , with the understanding being that if iran developed a weapon, Saudi would be able to counter it the same day" ] }
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[ [], [], [ "http://ieer.org/resource/south-asia/short-history-of-kashmir-dispute/" ], [], [], [], [], [], [ "http://www.globalfirepower.com/countries-comparison-detail.asp?form=form&amp;country1=india&amp;country2=iran&amp;Submit=COMPARE" ], [], [] ]
upqg1
everyday uses for calculus.
My cousin is really grumpy because he thinks calculus is quite useless, and he has a lot of that in high school, I was wondering if you could come up with some uses for everyday situations. By the way, he wants to become a chef someday.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/upqg1/eli5_everyday_uses_for_calculus/
{ "a_id": [ "c4xfu0d", "c4xhait", "c4xhe6h", "c4xi5vi", "c4xign6", "c4xiu41", "c4xnrn0" ], "score": [ 10, 29, 34, 17, 5, 15, 2 ], "text": [ "How about the optimum area for pasta for a lasagna dish? ", "You're not going to sell him on calculus itself being useful. Frankly, it isn't outside of specific fields. But it is excellent brain training.\n\nThink of an athlete, say a football player. A football player will go to the gym, and will do tons of bench presses. Now, at no time on the field will he by lying on his back trying to lift 400 pounds. But the muscles he gains from training help him in various tasks.\n\nCalculus is the same way. You may never use it, but the mental connections, and the different ways of analyzing data, and the basic logical proficiency will be useful to you in many different ways.", "You're thinking about it the wrong way, and so is he.\n\nWhat use is analysing poetry, in everyday life? What about playing piano? What about leaning how chemicals react? What about speaking foreign languages (assuming you don't travel abroad much/have some other obvious use for them)? What about *pretty much* ***everything*** *you learn in school*? Why pick out maths as the one \"pointless\" thing you learn, when in actual fact almost everything you learn has no direct relevance to \"real life\"?\n\nThe main purpose of school is that it actually teaches you *how* to learn. Practising the logical methods needed to understand calculus, along with the self-discipline of studying it, is what's important here.\n\n--Also, basic calculus is very easy, and is *way* overrated for its difficulty by most people ;)", "You can use calculus to figure out how to maximize your profits for certain business scenarios.", "As a chef there's not much chance he'll be integrating things on paper during his job. However, calculus teaches you to think in a very useful way. Understanding the concepts of area under the curve and slope = acceleration make every day life more interesting and comprehendable. Being able to refer to these things in conversation can make explanations of situations easier, and frankly if someone doesn't \"get\" a basic calculus reference, I see them as uneducated. ", "Calculus is a more rigorous approach to basic math functions you learned in primary school - it is sort of the basis in any advanced career field. I am a still an undergrad engineering student but I'll try to tell a few of many (and I mean **many**) applications of calculus.\n\nApplications: Say you are a top chef in a 5 star hotel, you are in charge of overhead in the kitchen, which includes ordering the ingredients from markets for your wonderful menu. Because you took calculus, you derive a mathematical equivalent of your diminishing ingredients over time. Instead of wasting hours of your staffs time (time = money) of individually counting every single ingredient numerically, you work hard in the kitchen, developing new recipes and take 5 minutes to call the supplier for the correct amount of ingredients. You also have an efficient business model, because of calculus, you can determine at what price you sell your dishes to get the most revenue, with that extra revenue, you hire the best chefs, chefs who like you, have a passion for innovating the food menu. \n\nYour time spent on innovating your menu attracts attention, local food critiques are going wild, and eventually big stars come in and enjoy your food, one of which is also a producer and is so impressed with your skills, offers a pitch for you to appear on national television promoting to your style of cooking. You have books written over you, investors pouring in with ideas for expanding your own line of restaurants and food products - You, yourself become a star. \n\nThere isn't any tangible effects on learning calculus like Dreadfulrauw stated. Just as Math is a tool, like a chisel and hammer- basic arithmetic can be used for almost anything, Calculus is just a more advanced tool, like a CNC machine (google it) creating real relationships as functions stated mathematically, and then going on worth from there. Without one, there couldn't be the latter, but without the latter, we wouldn't have the benefits in society today. \n\n ", "I love how he discredits higher mathematics, which is used by people who make quite a bit of money, and yet he goes off and has a low paying job." ] }
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2bjok1
how does a suicide barrier on a bridge work and won't people who want to commit suicide just find a different bridge?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2bjok1/eli5_how_does_a_suicide_barrier_on_a_bridge_work/
{ "a_id": [ "cj5zg68" ], "score": [ 13 ], "text": [ "The goal when it comes to suicide prevention is to just make it slightly less convenient in order to buy some time. Mentally unstable or depressed people generally do not want to kill themselves 24/7/365. They usually find themselves in a terrible state of mind for short periods of time, and if you can just keep them from killing themselves momentarily they will probably shake it off enough to get to the point where they aren't immediately willing to go through with it, at least for a while.\n\nYes, if someone wants to kill themselves and they are 100% committed, there are countless ways to do it, and you won't be able to stop them. But most people just need to be discouraged from it momentarily, not prevented completely." ] }
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2xx02u
if modern stealth aircraft have a radar cross-section of a bird, why doesn't enemy radar simply track the 800 mph small bird signals?
Is the that just too small an effective area to get a useful signal from for radar tracking? I guess I just always pictured the explanation about the effective radar signal of a stealth aircraft as being equivalent to the radar signal that a bird would give, but wouldn't the speed and behaviour of the aircraft still give it away?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2xx02u/eli5_if_modern_stealth_aircraft_have_a_radar/
{ "a_id": [ "cp44u7o", "cp44uax", "cp46zxk", "cp472oa", "cp4cvmb", "cp4da50" ], "score": [ 15, 18, 5, 4, 2, 3 ], "text": [ "It is so small that many systems simply cannot see it, and those that can do not generally do so reliably, as you yourself guessed. ", " > Sir, we're tracking a sparrow coming in at mach 2.\n\nAh just ignore it, sparrows are harmless.", "One of these days, some clever individual is going to twig to this bit of old technology:\n\n_URL_0_\n\nStealth aircraft may be damn near undetectable to radar, but they still make noise like Satan's Own Farts. With acoustic detection concepts updated with modern tech, such as computerized signal processing, long-duration aerostats and so on, it would be fairly easy to detect encroaching aircraft--stealth or non-stealth--without radar at all.\n\n", "The answers here are pretty accurate, but another factor is that most radars can't identify the small birds until they're well within weapons release range.", "Because enemy radar is calibrated to ignore birds and only pay attention to enemy, besides, you can't get a live image of the object, it would have to be updated every few seconds, and by then the dot would have moved so far that it is hard to identify.", "Speaking of stealth aircraft, I have this idea written on my iPad, you guys seem to know what you're talking about, feedback?\n\nWhy don't they coat military aircrafts with mirrors (or something similar, but stronger, obviously) to make laser guided missiles useless? Right now, the military paints stealth aircraft black so that as little light bounces back to the sensor on the missile as possible. But if we were to cover it with mirrors, the light would just bounce away in some other direction, away from the missiles' sensor. Obviously, mirrors are a bit to delicate to coat military fighter jets with, so they would have to use something similar, like chrome steel. The military has done some research in using lasers to shoot down missiles, but I doubt this will ever catch on because you can just coat it in mirrors and make it laser proof! " ] }
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[ [], [], [ "http://www.funzug.com/index.php/informative-zone/aircraft-detection-before-the-invention-of-radar.html" ], [], [], [] ]
klihe
how does xbox live work?
Ie my controller movements, how does it know how hard im pressing the trigger and how can it do so in real time alllowing me to our BR on halo or overtake someone in Forza?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/klihe/eli5_how_does_xbox_live_work/
{ "a_id": [ "c2l81sc", "c2l81sc" ], "score": [ 3, 3 ], "text": [ "Well how hard you pressing the trigger or the joysticks is controlled by a potentiometer. Simply it is a variable resistor that translates the joystick position to a digital signal. The input signals are translated again to game data. The game data that needs to be shared is sent to the host player (generally the one with the best connection) and rebroadcasted to the other players. ", "Well how hard you pressing the trigger or the joysticks is controlled by a potentiometer. Simply it is a variable resistor that translates the joystick position to a digital signal. The input signals are translated again to game data. The game data that needs to be shared is sent to the host player (generally the one with the best connection) and rebroadcasted to the other players. " ] }
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7epsjr
why caffeine makes us (me) feel good and powerfull, then sh*t?
Hi all, I don't know if everybody feel the same, but everytime I'm caffeine loaded, I feel good, powerful, and my self-esteem reaches impossible level without. Then I feel like sh*t and need more caffeine. I'm quite a caffeine addict, I estimate my daily dose between 500 and 600mg. Would it be possible to explain to me like i'm five: 1) why caffeine does this effect? 2) why I tend to incrase my caffeine intake? Is there a saturation of sole receptors? 3) Is there a way to replace caffeine with something else? Some of my colleagues are quite concerned about my daily intake. Is there any long term risks with a such dosage? Thanks all!
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/7epsjr/eli5_why_caffeine_makes_us_me_feel_good_and/
{ "a_id": [ "dq6myjl" ], "score": [ 3 ], "text": [ "Caffeine binds to special receptors to the brain that stop the chemical signal that makes you feel sleepy and tired. As a result you feel energetic, after continued consumption of caffeine some receptor get tired and the body decides to make more receptors. The increase in receptors makes it so that the amount of caffeine you ingested on a regular basis doesn't fill the receptors making you want more caffeine. After caffeine leaves your system, the sleep inducing chemicals have accumulated so much that they give a feeling of a \"crash\"." ] }
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1hurvf
how do we measure time? why are atoms or crystals able to measure time?
I never understood this. What do scientists mean when they say they've created the most accurate clock ever?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1hurvf/eli5_how_do_we_measure_time_why_are_atoms_or/
{ "a_id": [ "cay4huk", "cay4iao" ], "score": [ 2, 11 ], "text": [ "We don't actually measure time. We have defined seconds and hours ourselves and we 'measure' time relative to that definition. These scientists are just being commercial. It sounds good to have \"the worlds most accurate clock\". \n\n\nBTW; the current definition of one second: \n*the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom.*[link](_URL_0_)\n", "put as simply as possible: some things vibrate at a certain frequency when you put a certain amount of energy into them. As this frequency is constant and in the case of atoms, highly stable, you can simply measure the intervals between oscillations and you can predict how many oscillations you need to measure a day, how much you need to measure out a year, etc." ] }
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[ [ "http://tycho.usno.navy.mil/leapsec.html" ], [] ]
4xoo3g
how grocery stores have fresh food everyday?
[deleted]
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4xoo3g/eli5how_grocery_stores_have_fresh_food_everyday/
{ "a_id": [ "d6h9dhg", "d6hc3zv", "d6hcqz3" ], "score": [ 2, 3, 2 ], "text": [ "A lot of produce is artificially ripened, or the ripening is controlled, so a batch of plants can be picked earlier and a batch later and still ripe for sale. A lot of produce is also imported that's why fruits/vegetables in-season usually taste better and are cheaper, because they ripen naturally for longer and don't need to be shipped as far. As for most things grocery stores typically get shipments every 2 days.", "There a couple of ways:\n\n- Not all crops ripen at the same rate, so even within the same farm they may harvest numerous times over the course of a picking season\n\n- There are ways to slow down or speed up ripening in storage through temperature and air composition (amount of oxygen, nitrogen, carbon dioxide, ethylene gas, etc). The average apple bought in the grocery store is 14 mo. old, from the previous year's harvest! Other produce isn't as hearty, but there is still some ability to hold produce for weeks/months to even out supply. I got to see a big produce distributor's warehouse, and they have giant, garage sized rooms with different mixes of air and temps so that a single truckload of bananas could be ripened to 4-5 different specs before shipping to store and restaurants... and typically an order would specify a range so that they have ones ripen over the course of the few days/week between deliveries.\n\n- Different growing regions. Blueberries bought in the winter come from Chile or Argentina. In the spring, they might come from South Carolina and Georgia, and in the summer they come from Michigan and Wisconsin.", "Most of the meat industry have it a bit easier than the crop farmers. They basically call the buyer and say \"in about 15 weeks, I have 2500 units for delivery. When would you prefer to have them?\" And the answer could be anything from \"yeah, 15 sounds good\" but can just as well be \"nah, I would prefer 16.\"\n\n...and then, out of the blue the buyer can call you one day and say \"I know that they are not yet ready for delivery, but I'm willing to pay [extra amount] if you can deliver on Friday.\"\n\n\nIf you grow tomatoes instead, and have a green house, you have some growth control. You can delay delivery a few days by changing the settings of the lights, but in general you have a product that has to be delivered when it's ready and that is that. Since everyone knows this, the farmers have an incentive to plan delivery together so that everyone get reasonable pay every time.\n\nFor that very reason, most green houses have a delivery day; they always deliver on Thursdays. Or Monday's. Or every third Wednesday. They make an educated estimate on the amount they can deliver a few days in advance, and offer it to the buyers. The green house is generally speaking large enough to have sections that are in different stages of development, and if they miss a delivery or happen to try to deliver in the middle of a nationwide strike affecting all grocery stores it will only affect a partial amount rather than the entire months income.\n\nThe buyers in turn offer the amount you have offered them to the different industries and grocery store chains and restaurant suppliers. They know that the buyer has product every day of the year, and frankly do not care who's greenhouse it's been in, they buy from the buyers marketplace. The market place will, over time, be remarkably good at guessing the demand and will on a day to day basis encourage sellers to deliver or hold deliveries by setting a price every day depending on the amount already available on the market.\n\nEDIT: oh, actually. Some really large greenhouses actually do deliver more or less the same amount of tomatoes every day. Or at least more or less the same amount every time they deliver." ] }
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29zmql
why doesn't the mls and usl combine so teams can be promoted and relegated
The relegation system is used basically everywhere else football/soccer is relevant. It makes the games between lower teams in leagues much more exciting. Also I believe it would exponentially increase the interest in American football/soccer. I, for one, would love to see this happen, I would actually start to watch the MLS. Also I haven't seen anyone ask this before on this subreddit so I would love to here an explanation.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/29zmql/eli5_why_doesnt_the_mls_and_usl_combine_so_teams/
{ "a_id": [ "ciq978u" ], "score": [ 2 ], "text": [ "Simply put, MLS owner agreements stipulate that the owner has the right to a top-flight team, therefore, possible relegation is out of the question according to those said contracts." ] }
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9nx60i
what exactly is "alternation of generations" in plants?
What's the difference between, and some examples of, sporophytes and gametophytes? What do they look like? Which ones are haploid and diploid? Better yet, I'd appreciate a detailed but simple explanation of the lifecycle of a plant. Thanks in advance!
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/9nx60i/eli5_what_exactly_is_alternation_of_generations/
{ "a_id": [ "e7ptdhk", "e7usfmw" ], "score": [ 4, 2 ], "text": [ "This is kind of a loaded question since there are major differences between the reproductive behaviors and lifestyles of different plants, so for what I’m writing the example I’m going to use is a fern because I remember the information about ferns the best for some reason and the plant itself isn’t very complicated. \n\nSo let’s say you go outside and see what most people typically recognize is a fern. That plant is actually the sporophyte version of a fern, that is, it creates spores (which leave from the little bumps on the bottom of the leaves) that then get spread around via wind and eventually go onto the ground and begin to form the gametophyte. The gametophyte of a fern is actually something pretty unique in that you can’t readily see it, it’s a little patch on the ground that is hidden underneath leaves or a myriad of other things most of the time. This gametophyte is what has (both) sex organs, which then release sperm through the male antheridium and have eggs inside the female archegonium. The names aren’t very important as the general idea that this mass has both male and female organs. Most of the time, the male sex organs of one plant will fertilize itself, when this happens, the sporophyte begins to form again. \n\nNotice how here the gametophyte gives rise to the sporophyte, and the sporophyte then also gives rise to the gametophyte. That is what is meant by alteration of generations. The haploid gametophyte makes a diploid sporophyte which then makes another haploid gametophyte, if that makes sense.\n\nEDIT: Also for the last part, to be a plant, there has to be an alteration of generations that’s one of the qualifying characteristics of plants, not all plants use spores like the fern and there are many different more specific types of plants like trees that have very different reproductive characteristics, too. This was just to give a detailed example about the question so if you want to know something specific about a different plant, just google it tons of information will come up.", " Alteration of generations is the phrase to describe the life cycle of typical plants, like the land plants you are used to seeing, trees, bushes, also algae and such, and it is told from a genetic point of view.  It is the process of a mature plant with normal count of chromosomes, producing spores, which have half the number of chromosomes (analogous to egg cells and sperm cells in mammals).  The spores later combine in plant sexual reproduction to produce viable plant seeds, and this process facilitates diversity and response to evolutionary pressures in plants.  \n\n & #x200B;\n\nThe main thing about \"alteration of generations\" is that it's primary genetic process is meiosis, which produces the spores with half the proper count of chromosomes, and this meiotic process is somehow involved in DNA maintenance and repair, although interestingly enough, the exact process is still not well understood by botanical biochemists, which is surprising to me. I would have thought this basic biological process would have been well understood by science by now. " ] }
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3791dq
why are newer movies less realistic than the older ones?
The older horror movies have greater ratings and the newer ones have very low ratings.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3791dq/eli5_why_are_newer_movies_less_realistic_than_the/
{ "a_id": [ "crknxwb" ], "score": [ 7 ], "text": [ "First off, high ratings do not mean realistic. They're unrelated areas.\n\nSecond, you're comparing *all* current day horror movies to the best of the best from older generations. Yeah, there are lots of awful movies which come out now, but it's not like every horror writer was a Hitchcock back in the day. \n\nThird, a lot of the classics get extra marks for inventiveness and a sense of precedent. Some of the \"best\" horror films of all time get that title by being the first to do something. When compared to a modern film, the older one may well have worse execution or production values, but it is novel, while the new one is just a rehash of older ideas. Even if the new one is better when viewed in a vacuum, in real life it's old hat. " ] }
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eijsgl
why are the tectonic plate boundaries of the pacific ocean along the coast, while those of the atlantic run through the middle?
Image for reference: [_URL_0_](_URL_1_)
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/eijsgl/eli5_why_are_the_tectonic_plate_boundaries_of_the/
{ "a_id": [ "fcr2of7", "fcr3lml" ], "score": [ 2, 2 ], "text": [ "Around the Pacific you nave a convergent boundary so the plate is moving towards each other and is colliding but in the Atlantic, you have a divergent boundary and the move apart. You image shows that where you have an arrow toward each other you get land but when the move apart you get sea floor.\n\nWhen two plates collide both get deformed. You have one plate moving down and melt and result in volcanic activities in the plate above. So around the pacific, you get mountain ranges with vulcanoes where the plate meat.\n\nWhen to plant diverge you have most of the time a slow continuous release of lava from below to produce a mountain range that most of the time is below the surface but emerge in som location like on Iceland. So the Atlantic seafloor has been formed after the continents pulled apart when the plates grew from new lava.\n\nSo plats that move towards each outer press stuff up so you will produce land where if you pull them apar new lava will flow out but not as high and form underwater mountain ranges.\n\nLook at [_URL_0_](_URL_0_) to see the effect of plates diverging.", "Crust under the oceans, and deep under the land is denser then the continental material making up the top part of the land. So when you get an ocean closing up, like the Pacific still is after the Pangea supercontinent broke up, the continental crust rides up over the oceanic, pushing the latter down. Therefore the subduction zones tend to be at the edges. Where two parts of continental crust collide, you get mountains like the Himalayas.\n\nSpreading can happen anywhere but the weaker strength of the thinner layer is more likely to split in the oceanic crust. However it also happens in a continent, e.g. Great Rift Valley in eastern Africa and the Red Sea." ] }
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[ "https://upload.wikimedia.org/wikipedia/commons/thumb/8/8a/Plates\\_tect2\\_en.svg/4167px-Plates\\_tect2\\_en.svg.png", "https://upload.wikimedia.org/wikipedia/commons/thumb/8/8a/Plates_tect2_en.svg/4167px-Plates_tect2_en.svg.png" ]
[ [ "https://www.earthmagazine.org/sites/earthmagazine.org/files/2016-05/TharpHeezenMap.png" ], [] ]
4ia6p4
why is obesity considered a disease?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/4ia6p4/eli5_why_is_obesity_considered_a_disease/
{ "a_id": [ "d2wddm8", "d2wdt0j", "d2weby2" ], "score": [ 3, 5, 3 ], "text": [ "It's certainly a disease; it's horribly unhealthy and shortens your life. The question and ongoing debate is whether the root cause is physical or psychological.\n\nThe truth is almost certainly \"a bit of both\". Some people simply have faster metabolisms than others, but psychology and upbringing also clearly play a huge role. ", "I have a disease that doesn't seem very \"disease-y\" and when I asked the doctor how on earth it ever got be be called a disease he said, \"Any time a bodily system doesn't work the way it's supposed to, it's a disease.\"\n\nSo assuming that's a fairly accurate description, then if whatever mechanisms that are supposed to keep you from overeating aren't working, then it's a disease?\n\n(Personally, it sounded like a load of baloney to me. I also have bad vision, but that's not a \"disease.\")", "Here's the thing, it's both. The definition of disease itself has both clinical and ethical aspects to it.\n\nClinically, obesity is considered a disease because it dramatically reduces lifespan, and is a significant contributor to mortality and morbidity in the modern world. Pretty undeniable fact after almost two decades of research. It's linked to cardiovascular complications, diabetes, hepatobiliary problems, pulmonary dysfunction and a bunch of other morbidities. In fact, these problems occur so commonly together, doctors have a new term describing this collection of manifestations: [Metabolic Syndrome](_URL_0_).\n\nEthically though, it gets trickier. Classifying obesity as a disease would mean that medical practitioners would be obligated to treat it as such:\n \n\n * Utilitarians and other people concerned with 'the greater good' would support classifying obesity as a disease because that means more people get treated = less mortality & morbidity = good outweighs the potential harm.\n\n\\\n\n* However, in society, people that are obese have a stigma attached to them nowadays with the media and emerging social norms. Deontologists and people that have absolute rules (e.g. discrimination is bad, bulling is bad) would support NOT classifying obesity as a disease, because that means we pathologize them and deem them to be of 'lesser' status.\n\nBasically, obesity is considered a disease clinically because it's tied to a bunch of things that shorten our lifespan. Philosophically, whether obesity counts as a disease will depend on your personal beliefs and social context." ] }
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[ [], [], [ "https://en.wikipedia.org/wiki/Metabolic_syndrome" ] ]
3dxv4v
how come the amount one feels they have to pee does not correlate to how much they end up peeing?
Sometimes it may feel like you have to pee really badly but it will only be like a 5 second pee. Other times it feels just a little pressure but you may end up peeing for over a minute. Also sometimes it feels like one may have to pee very frequently for a little bit. Why wouldn't it be just one thorough pee?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/3dxv4v/eli5_how_come_the_amount_one_feels_they_have_to/
{ "a_id": [ "ct9qy2a", "cta466o" ], "score": [ 4, 2 ], "text": [ "The amount of urine you get rid of when you pee isn't only related to the time it takes to get it all out. \nWhen you feel like you have to pee a lot the pressure can build to a much more rapid stream that expels urine faster so you don't spend as long peeing, but you get rid of more.\n\nYou can experiment with this by filling a balloon with water and putting a straw in the hole. Wrap tape to keep the straw in the balloon. If you just turn the balloon over you will see it drains at a certain rate. Now do the same thing again, but this time put pressure on the balloon by squeezing it steadily. This acts like the muscles contracting to empty your bladder. The water will come out much faster so the balloon will take less time to empty.\n", "Couldn't this be a result of other factors like fullness which could cause your stomach to press on your bladder indirectly?" ] }
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2q4cox
how did pope francis get elected when he seems so willing to blast the vatican's senior clergy?
My question isn't so much the mechanics - the pope is elected by the college of cardinals during the papal conclave. What I don't understand is how this particular pope was able to gather so much support when he is radically revising the church, demoting clergy, blasting the values of senior leaders, rewriting laws, etc. It seems like if the cardinals wanted all that to happen they could have done it on their own. Assuming they didn't want such radical revisions then how did they elect someone who did?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2q4cox/eli5_how_did_pope_francis_get_elected_when_he/
{ "a_id": [ "cn2qe9x", "cn2qxwz", "cn2r2va", "cn2v42q" ], "score": [ 2, 4, 4, 2 ], "text": [ "In large part, the papacy of Benedict XVI was pocked with various scandals in the Vatican. I suspect the college of cardinals was looking for a reform minded candidate, and Jorge Bergolio fit the bill. Bergolio was also said to have been 2nd in the voting to Joseph Ratzinger before Ratzinger was elected Pope Benedict XVI. (This is impossible to confirm, because the votes of the college of cardinals are not public)", "This isn't the first time in modern history a Pope has been a bit more liberal. In the 60s, Pope John XXIII was a massive change for the Church, and bought about more modernisation to the Church than any other Pope I can think of. After him, Paul VI carried on this sentiment, and John Paul I would have been, I believe, more radically liberal than Francis. Sadly, he died extremely early on. After him, John Paul II and Benedict came along and bought to a halt what John XXIII started in the early 60s. To me, Francis just seems to be picking up where John Paul I left off.\n\nFrancis isn't really revising much about the Church compared to John XXIII, who held the Second Vatican Council and made enormous changes. Moreso, he is steering the Church, well within dogma, towards a much more amicable institution, trying to work past the scandals of previous decades. He is not rewriting official teaching, just reinterpreting.\n\nA lot of seniors in the Catholic Church love to see change, which is something we find hard to digest from the outside, because we've been fed this idea that it's an institution that never changes. Francis is a great guy, and we can't assume that these changes are not welcomed by the majority of officials in the Catholic Church.", "We don't know exactly what happened, but it was predicted that they would like a non-European pope because the largest demographic of Catholics are now outside of Europe. Francis has the advantage of being Latin American yet has connections to Italy, so he happens to become the most eligible candidate under these criteria. The other front runner is Italian Cardinal Angelo Scola. Being Italian gave him the disadvantage of inadvertently creating a lot of enemies within the other Italian cardinals, so he became disenfranchised. ", "Benedict was unpopular and linked to the sex abuse scandal, so electing another insider would be seen as more of the same at a time church attendance was dwindling. A reform minded outsider seemed to be just what the church needed.\n\nAnd it is working out for them. While some insiders bristle at losing their privileges, Francis has been a refreshing new face of the church and has helped to restore the trust of the laity." ] }
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1y91tz
tax season
Why do they make people even bother with this? I know people love the feeling of getting a tax return, but it'd be more efficient if they just didn't take that extra money in the first place...
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1y91tz/eli5_tax_season/
{ "a_id": [ "cfidrjf", "cfidyty" ], "score": [ 3, 2 ], "text": [ " > Why do they make people even bother with this?\n\nYou mean withholding? If the government didn't withhold or sequester the funds in some way, they'd see a pretty substantial spike in delinquent/unpaid taxes. You can't trust millions of people to set aside cash for a full year to pay their taxes.", " > it'd be more efficient if they just didn't take that extra money in the first place...\n\nThe problem is that your employer can't possibly know exactly how much money to withhold from your paychecks, because various life events and personal decisions can affect your tax obligation. \n\nFor instance, maybe you bought a new home and can deduct your mortgage interest payments. Or maybe you donated to charity. Or perhaps you got married halfway through the year, or had a baby on December 30th. Or maybe you work two jobs. Or you got a tax rebate for installing solar panels. Or you lost your job partway through the year. Or you started paying back a student loan.\n\nThere are all kinds of life events that will change your tax obligation, and which your employer is not aware of. The purpose of \"doing your taxes\" is to retroactively apply all of the tax-affecting circumstances to your previous year's earnings to come up with your *actual* tax obligation, and then reconcile that with your per-paycheck estimated payments." ] }
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9xr1rw
how does probability work?
Hi, I'm having trouble understanding probability and was hoping to gain more insight. & #x200B; For example- Say you roll a 1 on a 6 sided die; the chance of this is 1 in 6 (16.67%). Say you roll again and get another 1. & #x200B; What is the probability of this? & #x200B; If there's a better example please feel free to share, thanks! & #x200B; **EDIT-** Thank you for all of your responses!
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/9xr1rw/eli5_how_does_probability_work/
{ "a_id": [ "e9uhelf", "e9uht9b", "e9uigvh" ], "score": [ 12, 3, 2 ], "text": [ "The probability of a second roll coming up a 1 is another 1 in 6. Because the result of the first roll has absolutely no effect on the result of the second roll, each individual roll has the same probability.\n\nNow, if you want to know the probability that you will roll the same number twice, then it is 1/6 * 1/6, which equals 1/36. To happen a third time, you multiply by 1/6 again, etc. Each roll reduces the probability of being the same number by an equal amount.\n\nFinally, the last kind of probability is when the first result does have an impact on the second result. You really cannot explain this with dice, so lets use colored balls:\n\nYou have a bag, and in it are 6 balls. 3 balls are blue, and 3 are red. You reach in and randomly select a ball. There is a 3/6 chance of it being blue, and a 3/6 chance of it being red. So, 50-50. Lets say you pull out a red ball.\n\nIf you put the red ball back, then the odds of pulling another red ball are calculated the same way as rolling the same number on a die: 3/6 * 3/6. \n\nIf you leave the first ball out, you change the probability of pulling a ball the second time. Now, there are 3 blue and only 2 red. Lets say that you want another red ball. Since there are fewer possible results for a red ball (2/5), it has a different chance than if you put the first ball back. Now it is 3/6 * 2/5 to get a red ball twice.\n\nNote: all of the above #/# are to be read as fractions.", "The probability of rolling a 1 stays the same but the probability of rolling two 1s in a row is different. So the probability of rolling a die and getting a 1 is 1/6. If you roll it again, the probability stays the same (1/6). This is because you rolling the die the first time and you rolling the die the second time are independent events, meaning that the number that the die lands on the first time has no effect on the number the die lands on the second time.\n\nHowever, the probability of getting two 1s in a row is 1/36 (1/6*1/6).\n\nThe problem most people have when first encountering probability is the idea that (in this case) if you were to roll the die 6 times, theoretically, you should only get a 1 once (1/6 times) and every other number once. But, in reality, you don't. This is because it's a **probability**. It's not set in stone. The idea is that the larger your sample size (the more times you roll the die), the closer your results will become to the expected results.\n\nSo, for example, if you roll a die 6 times, you might not get one of each number. In fact, you most likely won't. But, if you were to roll that die 10000 times, you would see that the number of times you get each number on the die are starting to become very close in value to each other. Roll the die 1 billion times, and the number of times you get each number on the die will be even closer to each other. The reason behind this is that a small sample size has bias, so the more you increase the sample size, the closer your results from the die will be to the actual probability. \n\nTo summarise this, in theory, if you had an infinite sample size with set (unchanging) probabilities and independent events (events that don't affect each other's probabilities of occuring) then the outcome of whatever you're measuring will be equal to the probability. In context, if you rolled a die an infinite number of times, 1/6 of the rolls would give you a 1, 1/6 of the rolls would give you a 2, etc. So each outcome would have occurred an equal number of times.", "Rolling a die is a good example of an *independent event*, because past results don't affect future results.\n\n & #x200B;\n\nThe odds of rolling a 1 is still 1 in 6, and will always be 1 in 6 every time you roll.\n\n & #x200B;\n\nIf you're wondering what the odds of rolling a 1, and then immediately afterwards rolling another 1, then we want to multiply the odds of each independent event together. 1/6 times 1/6 equals 1/36.\n\n & #x200B;\n\nAs an aside, one of the important things to study in probability are keywords and their corresponding rule:\n\n\"What are the odds of rolling a 1 **and** then another 1?\" - multiply the two probabilities together (multiplication rule)\n\n\"What are the odds of rolling a 4 **or** a 5?\" - add the two probability together (addition rule)\n\n\"What are the odds of **not** rolling a 6\" - take the probability and subtract it from 100%. (complement rule)\n\nThe bolded keywords tell you what operation to use, and it always works as long as it's an independent event.\n\n & #x200B;" ] }
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yr9xm
is there an evolutionary purpose to different facial structures in different races?
This isn't a racist question, just an observation. I know darker skin is beneficial with things like sun exposure so I'm curious if things like a flatter face in people with Northeastern Asian ancestry or a larger bump on the nose in people from India serve any type of purpose or if they're simply coincidental.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/yr9xm/is_there_an_evolutionary_purpose_to_different/
{ "a_id": [ "c5y3nma", "c5y6bkr", "c5y6xir", "c5y7e55", "c5y8n7v" ], "score": [ 43, 15, 12, 5, 9 ], "text": [ "The 'epicanthic fold' which is the skin fold of the upper eye lid charateristic of East Asian populations, although it does also occur in Amerindian and European populations, is theorised to be a protection for the eye against the elements in regions with very cold winds and long periods of very bright sunlight. \n\nNose shape correlates roughly with temperature, a flatter nose being better for conserving heat than one that sticks out, this extends to the inner structure of the nose with people of colder climates having narrower nasal passages that allow for greater warming on inhaled air _URL_0_ \n\nThere's also going to have been some influence from sexual selection and what past cultures found to be attractive. ", "I read recently that white people of European descend have downward facing nostrils and are 5 times more likely to have webbed fingers than other ethnicities. It is theorised that this has occured due to natural selection for the best swimmmers, as rivers and coastlines were where the concentration of the populous was and these pre-historic relatives lived off of a diet mainly consisting of fish and molluscs. So the best swimmers have nasal and hand adaptations thus swim better and catch more food in turn this makes it more likely for them to succesfully reproduce and pass on these genetic traits.", "There may be a few features that have been selected for, but I think most are likely due to genetic drift. If a genetic mutation arises and there is no selective pressure on it, then it is random chance whether it goes extinct or spreads through the population. When you have separate populations, different mutations will arise and take hold in those populations. This is the way populations become different from each other genetically. This can also cause phenotypic variation (differences in appearance) between the different populations. It is important to remember that not everything is adaptive. ", "Thanks for asking this question. It's been on my mind lately.", "In his book *The Third Chimpanzee*, author Jared Diamond spends an entire chapter explaining that although there are dozens of theories, nobody knows why or how different races evolved with different skin colour. I know that's not what you asked, but if we can't even figure out skin colour, I'm pretty certain that everything else is still unexplained, too.\n\nFrom memory, Diamond pointed out all kinds of flaws with saying that darker skin was an evolutionary protection against the sun:\n\n* Only recently (the 20th century) has skin cancer been a notable cause of death - throughout human history, cancer has been insignificant as a killer. \n\n* Of areas of the world with little direct sunlight, some have very fair-skinned people (Scandinavia), some have very dark-skinned people (parts of Africa and Australia) and some have medium-skinned people. \n\n* Scandinavians have only lived there for around 20,000 years - a very short time, evolutionarily speaking. At the same time, other groups who have lived in their area for hundreds of thousands of years have not developed skin tones \"appropriate\" for the sunlight of the region. \n\nI'm doing a bad job of explaining it, but it boiled down to \"every theory we know has holes in it, in the end we just don't know.\"" ] }
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[ [ "http://www.scientificamerican.com/article.cfm?id=the-shape-of-a-nose" ], [], [], [], [] ]
j8uqa
why do mosquito's and flies make that annoying zzzzzzz sound while flying, and why does it stop when they sit down?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/j8uqa/why_do_mosquitos_and_flies_make_that_annoying/
{ "a_id": [ "c2a33qh", "c2a33qh" ], "score": [ 2, 2 ], "text": [ "you know how if you shake a piece of cardboard it makes a \"wobble\" sound?\n\nnow imagine shaking a tiny peice of carboard *really* fast, that's like a flies wings, they move so fast that their \"wobble\" sounds like a buzz.", "you know how if you shake a piece of cardboard it makes a \"wobble\" sound?\n\nnow imagine shaking a tiny peice of carboard *really* fast, that's like a flies wings, they move so fast that their \"wobble\" sounds like a buzz." ] }
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1rka8w
the unabomber bombings
The story from start to finish.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1rka8w/eli5_the_unabomber_bombings/
{ "a_id": [ "cdo3mky" ], "score": [ 4 ], "text": [ "[I typed less keystrokes to obtain this link than you did to make this thread](_URL_0_)" ] }
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[ [ "http://en.wikipedia.org/wiki/Ted_Kaczynski" ] ]
37uncl
why do fashion shows always have ridiculous outfits that nobody would ever wear in the real world?
It seems like the more gaudy and terrible it looks, the more "fashionable" it is.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/37uncl/eli5_why_do_fashion_shows_always_have_ridiculous/
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Haute Couture technically only refers to a small handful of \"houses,\" mostly out of Paris (e.g. Dior, Gaultier, Chanel); other designers often mix in the outlandish concept pieces with more \"normal\" ones in their so-called Ready to Wear shows.\n\nOne important thing to keep in mind is that these high-end fashion brands tend to make only a small portion of their money on the clothing itself. The real profit lies in the sale of perfumes, accessories, and so on—so really, the important thing is developing the image of the brand in a cohesive, interesting and wide-ranging manner. This is what the \"unwearable\" outfits are for, apart from being art pieces: they establish a \"look\" for the brand in an often extreme but unforgettable way, show off the vision of the designer and the technical skill of the craftspeople/engineers, and even if they look ridiculous going down the runway they often photograph extremely well and thus are excellent for fashion magazines. Even the most avant-garde pieces can sometimes be toned-down and rethought for, say, an actress to wear on the red carpet (someone like Lady Gaga or Björk, of course, tends to just wear the original). \n\nThe other effect worth considering is that even some of the most bizarre outfits either 1. have pieces that are actually quite wearable and are just combined in a way that would give them the highest impact, or 2. a sort of \"trickle-down\" effect (well-described by that famous Devil Wears Prada quote about the cerulean) where bizarre and conventionally unwearable elements (e.g. [a silhouette where the hips are three feet wide](_URL_8_), [collars that cover most of the face](_URL_6_), [completely sheer dresses](_URL_4_) that show [EVERYTHING](_URL_1_), things covered in [broken glass](_URL_2_), [neck ruffs that envelop the whole body](_URL_0_), [antlers](_URL_5_)) can be re-purposed in the collections in stores in a much more wearable way, and which in turn get picked up by non-high-end designer lines as trends (e.g. the examples I gave above might respectively turn into skirts or blazers with slightly pronounced hip elements, pronounced high collars on jackets that don't actually cover the face, a use of sheer fabrics as accents or layering elements, elaborate sequining, complex ruff-like collars on blouses, and antler patterns or designs). \n\nThough I still can't describe [this](_URL_7_).\n\nEDIT: Added links to example pictures.\n\nSECOND EDIT: Thank you so much for the reddit gold. I'm glad I helped people understand something I also once found totally baffling!\n\n_URL_3_\n\nWarlizard Edit: Automod removed my explanation (which was a link to the original comment) for being too short, so I just copied it here.", "They're artistic expressions of broader concepts, like color or fabric. Similar to how concept cars at Auto Shows have crazy over-exaggerated features, gaudy paint colors, over sides rims and then the production model comes out two years later with a similar grill and overall profile but more sensible interior, smaller wheels, normal paint color options.", "Same reasons you have ridiculous concept cars at car shows. It's a demonstration of new ideas and innovation, intended to show the direction and aspiration of the company.", "Why do video game trailers show stuff that's impossible to actually do in the game? They set the mood, the idea, and theme of the game/clothing line.\n\nPlus they are fun for both the game designers and the gaming audience. Both parties know deep down it's an exaggeration.", "Dana Linn Bailey had it right in calling them Sewing Contests (her husband is a designer) because that's what they are. The models are simply there to showcase the design.", "Like most people said, it's artistic expression, however what seems to be missing in these answers is that the purpose of Haute Couture is so set the trends for the the silhouettes, the fabric, jewelry, makeup etc. What happens after that is trickle down effect. So runway shows will base their inspiration from those shows and trickle down some more so consumer wear. \nSo it's concept/inspiration wear. It's also a platform to show what the fashion house is capable of achieving/afford. ", "Terrible quality but this is a good scene from The Devil Wears Prada that explains how fashion shows translate into consumer wear.\n\n_URL_0_", "Like you, I never really understood fashion until someone told me to look at it not as clothing, but as an art medium. Museums have paintings, concerts have music, etc. Think of fashion shows as a way of artistic expression through an unconventional medium, instead of as clothing.", "Basically, those are not actually usable pieces of clothing. Most of the times they represent style/tendencies/concepts. What actually goes into sale are pieces that gravitate around those concepts.\n\n", "I think it's to showcase concepts and patterns/colors that can then be incorporated to everyday wear or something. ", "Why do art exhibitions always have ridiculous exhibits that no one would ever display in their own home? ", "Try to think of it kind of like a concept car. It's a prototype you only see at shows and although you don't see them on the roads, you may see glimpses of the original prototypes in newer cars that roll out soon thereafter. Similarly, if fringe or military wear is in vogue one season, then a big name haute couture designer will emphasize that concept for the season so the final result is piece that probably looks a bit ridiculous. But designers sitting in those shows that come up with pieces for stores like Banana Republic or Nordstrom will take note of what's being emphasized that season and filter what gets incorporated to their own designs so that it's accessible to the average consumer. So perhaps they will add fringe on a handbag or choose military style buttons over regular buttons or make other similar small yet appreciable adjustments to their new collection that keep in step with what's \"in\" that season. \n\ntl;dr haute couture is meant to inspire, not necessarily to be worn as is. ", "Sometimes they aren't designing practical clothes to sell, they are showing clothes as pieces of art.", "High fashion can convex lines between design and conceptual art. There is a base theme, or idea that is manifested and then used as predictions for the season. The most influential ideas then trickle down towards high street designers. With post modern culture and the Internet, particularly creative use of tumblr has made these processes a lot more complex but generally, in the industry, fashion week is like a premiering a film at cannes, only with a collection instead of a film, and different 'peices' instead of scenes.\n\nThere is a huge artistic and magical dimension to fashion. Please take a look at Alexander Mcqueen's work for an example of design that was huge, not only artistically poignant but also influential industry wise.\n\nOne of my personal favourites was the late Leigh Bowery, who designed pieces that would never be commercially viable, but we're consistently artistically simulating. He was a force to be reckoned with and the nature if his ending often deeply saddens me, but then I marvel at the splendour he left behind.", "So many replies so I'm not sure if someone said this but the wacky things that go down runways aren't necessarily for use. The ideas are taken from these envelope pushing designs and influence commercial clothing designers as well as other kinds of designers. Watch The Devil Wears Prada, they explain it better in the movie than I can", "I've asked my gf about this too. The short answer is the crazy clothes are art and not meant to be worn. \n\nSource: My gf designs clothes, works in fashion shows and has put on a number of college and regional fashion shows. She picks the designers and models too. ", "to show the general trend of the season, textures, garments, cuts, etc are shown in runways and then toned down versions are sold\n\nFor example, [this](_URL_0_) is a model in the 2015 spring summer rick owens show, it looks kinda weird and if you wore all the pieces together in public it would look bad, however in [this pic](_URL_1_) the person has integrated the shoes with more toned down pieces making for a very interesting and compelling outfit", "The same reason concept cars are so weird\nIt's meant to show off parts from the coming year, not to be a literal display of the next product", "These crazy outfits are usually concepts for other kinds of more usable clothing.\r\rFor example, if aa model were to wear an outfit made of orange cubes, that could represent the idea of making orange and autumn colored clothing with rigid lines and patterns, like the edges of the cubes.\r\rThis is just a general explanation, but it holds true with a lot of designs. ", "AFAIK the designer made it to show the world what CAN they design/do. And they will design a more normal line for the mass market.\n\nIt's like a painting for them(?) to express their emotion and skill withlut thinking any boundaries.", "There's only so much you can do with practical clothing. What they wear on the runway is more avant-garde, like wearable art.\n ", "Fashion shows are like paintings in a gallery. Most paintings are not photorealistic, but still evoke ideas, emotions, moods and can cause trends in the art as a whole.\n\nIf you were then to look for someone to do your portrait, you would look at their portfolio to see what kind of artist they are and pick one that is capable of evoking the image, the mood, etc that you want to represent you in your portrait.\n\nSo it is with haute couture. You look at a runway show and think, I like her ideas of color and structure , I want to hire her to design **wearable** stuff for me (or my store). Then they might use the themes from the show to design practical garments.", "Architecture. The process from what I've seen. Crazy concepts derived from irregular or random lines and forms, iterated through computer generated models that put surfaces on these figures which are then turned into feasible structures. Same thing, different take. Then there is the image thing with fashion as stated above.", "It is purely and simply a closed circle of \"artistic\" masturbation. \n\nWhat they show is usually objectively ugly as hell, but once you're established as a big name youre allowed to do shit like that. Fashion is sort of a big cartel.", "I look at it this way: Formula 1, for instance, races vehicles that would never see the light of day on a regular road. But the extremes those cars are forced into produces tech that works its way into the cars we drive.\n\nSame thing with fashion.", "There are several categories fashion shows. Ready-to-wear (RTW) or prêt-à-porter - most of the times these clothes are meant to be worn. Pieces from them go to the boutiques. On the other hand we have haute couture (HC) where things are getting crazy. There you can see plenty of unwearable fashion.\n\n\nWhy haute couture fashion even exist if the clothes are mostly unwearable? It's art. For designers fashion is a way of self-expression and form of art. They experiment with garments, textures, colors, dimensions, etc. to create pieces of art. As Warlizard pointed they use HC to show their vision, the limits of their talent, etc. The most bizarre pieces exist as an experiment.\n\nDoes anyone buy HC clothes? Well we can't know for sure if every piece is sold. They are, of course, unique. Some are worn by fashion eccentrics. People like [Anna Dello Russo](_URL_1_), [editor-at-large](_URL_0_) for Vogue Japan. There are plenty of socialites who can afford these kind of clothing and they really love fashion. Also Lady Gaga and the like. \n\nAnother pieces are bought by wealthy women. Surprisingly [the Middle East happens to be a great market](_URL_2_) for this kind of clothing. We talk about opulent parties where only the women of the richest people in the world attend. \n\nWhy there are RTW shows with ridiculous clothes, why they don't have HC shows then? You can't just say \"This show is a haute couture show\". The term haute couture is protected by law (yeah, France is serious about fashion) and there is an institution that decides which fashion houses can produce HC. *Chambre de commerce et d'industrie de Paris* decides which ateliers are eligible to create HC who become members of *Chambre syndicale de la haute couture*.\n\nThe requirements are very extensive and a few houses even attempt to be recognized as a HC house. Now they are around 15 (and they change every year) while there are hundreds of shows every year only in the main fashion weeks (Paris, Milano, London, New York). And one of the requirements is to have a workshop in Paris. There are exceptions called *correspondents* for houses outside of France. Only a few houses like Versace and Giorgio Armani are correspondents. So some designers decide to opt out and just do their RTW as haute couture because that's what they like. They enjoy fashion as an art.\n\nOh, and one of the reasons these unwearable clothes are gaining popularity is because of street fashion around the main fashion weeks. There are many photographers who take photos of the people coming to the shows. These people are editors, stylists, fashion buyers, bloggers and, of course, celebrities. So most of the \"fashion pack\" (people who work in fashion) try their best to be noticed. Though they wear mostly RTC but still sometimes ridiculous. ", "Think of it as films and real life. Things exist to make a point but won't happen in real life. \n\nor think of it as porn! There are things that can happen to human body and for people to enjoy but in reality any of that thing is useless and adds no value to your dignity by doing it!", "Fashion shows have multiple purposes, and they depend on the house and maturity of the brand.\n\nThe first is to position the brand. This means to set or reflect the expectations within the mind of the audience for this brand. There is a very different expectation from Karl Lagerfeld at Chanel than Christopher Kane, Vivien Westwood or Versace. Brands need to maintain that position. The more outrageous garments therefore won't typically come from the established couture houses. Haute couture, by the way, is a regulated terms controlled by the Chambre de Commerce et d'Industrie de Paris, which decides who gets the nomination HC as well as the runway slots at the Paris Fashion Week.\n\nThe second is publicity. Fashion shows are one of the few ways to gain column inches or nowadays fashion blogger coverage. If you are Giorgio Armani you will be almost guaranteed coverage, no matter what you do - you are such a big advertising customer that they are obligated to cover you editorially. But if you are smaller or still looking for a break, you need to create something shocking. Gaultier is now established but he was the Prince of this technique in the 1980s. If you ever watch Project Runway you will heat the judges say something is \"editorial\" - they mean attention grabbing.\n\nThe third is sales. Fashion shows always show previews of clothes coming at least 3-4 months away, because they want the fashion buyers to place make orders for stocking in that coming season. That is why Spring/Summer is always shown in January, and Fall/Winter in June. The vast majority of runway clothes go unsold; Armani and other self-distributed labels like Prada and Chanel are exceptions, as they show what they will sell, and probably 80% of the runway will eventually make it to the stores. This is not the case for labels like Westwood, Kendo, Missoni or Casley Hayford, who depend on 3rd party buyers.\n\nI used to blog about my experiences with fashion and Giorgio Armani in particular, here's a couple of post about the economics of fashion shows:-\n\n_URL_0_\n\n_URL_1_\n", "I don't look at \"fashion\" as actual fashion that people would wear. When I started looking at it more like art, it started making more sense.\n\nI wouldn't want to hang every painting I've ever seen on my wall. A lot of concept cars I've seen looked ridiculous. And a lot of the artifacts found in museums (some suits of armor for example) weren't meant to be used, but displayed.\n\nSome fashion is meant to inspire or just invoke emotion. I don't personally get it as an art form, but there are lots of art forms I don't get. That doesn't mean the art form is wrong or bad, it just means that it's not my taste.", "I work for a small and expensive french brand that caters to an in-the-know crowd. the reason for the crazy stuff is:\n\n1. artistry - think of a fashion show as an artistic statement rather than only practical. even the more conservative large brands will put strange makeup on the models, it keeps it interesting and surprising.\n2. editorial - free advertising in the form of press coverage is important. the press wants something remarkable to talk about which gets your brand name out there.\n3. some of it sells. the brand i'm with is in many expensive stores globally. the selfridges and barneys of every major city but also those boutiques with the locked doors you need to ring to get in. its surprising but these stores will buy some of the really crazy stuff too, just not in high volume. the crazy stuff is always extra expensive so the economics works out even for small orders.\n4. people do wear these wild clothes actually but mainly for special occasions. you'd be surprised how many elaborate parties there are in the world that you never hear about. :o)", "I've always imagined as instead of them creating a new fashion statement, they're really just surrealist artists creating structures on real people. " ] }
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6g6ckd
how are powerstrips able to provide enough electricity for all the plugged-in devices, while the power strip is only plugged into one wall outlet?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/6g6ckd/eli5_how_are_powerstrips_able_to_provide_enough/
{ "a_id": [ "dinv7yb", "dinv9ti", "dinvdn8", "dinweil", "dio92u3" ], "score": [ 2, 3, 2, 3, 2 ], "text": [ "Depends on how many amps are being drawn from the circuit. Most outlets carry 15amps (i think), so as long as you stay within that range you're fine. Most people don't though.", "They can't provide more power than they take in. If you try plugging in 2 hairdryers you will probably flip a breaker either on the strip or in your house. On the other hand you can plug 5 ac adapters into them because they don't take much power.", "Electrical devices don't require the same amount of power. For example, a small vacuum cleaner might draw 200 watts, but a phone charger only draws about 2 watts. So theoretically you could plug 100 phone chargers all into the same outlet and draw no more power from it than that one vacuum cleaner. ", "tl;dr: Imagine you have a stack of 15 pizzas. The pizzas represent how much energy the socket can deliver in total, per 'event' (second). You invite people over to eat that pizza. One guy manages to eat a whole pizza by himself, and one girl (somehow) eats 4 and the crust of a 5th. Everyone else just eats a few slices. At the end of the event, you have 3 pizzas left over. In this example, each person is an outlet on power strip, and the pizzas are the total amount of energy the single socket in the wall can supply. Each person can only eat so much pizza at any given time, thus, you don't exceed the total amount of pizza you had, and everyone goes home happy.\n\nA typical home outlet supplies somewhere between 10-15A (A = amps). Most devices do not need all 15A to function correctly. Thus, the strip allows you enough plugs to make use of more of that 15A limit than the two outlets would normally allow you.\n\nA high-powered gaming PC, for example, might draw anywhere from 350 to 500 watts under full load. \"What is a watt?\" A watt is a volt-amp second. \"Wut?\" In the US power outlets in homes deliver power at around 120 volts. We already established the socket can supply up to 15A, so that means the socket can supply 120 * 15 = 1800W.\n\nOr, said differently, 500W / 120V = 4.1667A. So your gaming PC only uses 4.1A out of the 15 the outlet can supply. That's how the power strips allow things to share power, they assume that everything you plug in won't overload the outlet (if they do, you trip a breaker or burn out a fuse, depending on how your dwelling is wired).\n\nOne final note: It is very rare for each outlet in a house or apartment to be individually wired to a breaker. Some outlets will be, like the high-power outlets for an electric range or washer/dryer (each will have its own, specifically wired, circuit). But the normal wall outlets you'd plug a computer or cell phone charger into are normally grouped together. How many are grouped together varies from home to home, but the simplest way to test what outlets are grouped is to flip a breaker (or remove a fuse) and see which outlets stop working.\n\nIf you flip a 15A breaker, then discover that 6 outlets stop working in your house, that means that everything you plug into all 6 of those outlets, including any extension cords attached to said outlets, must never exceed 15A of draw, or else the breaker will flip (or fuse will burn out).\n\nModern housing codes mandate that each outlet be wired such that it can supply the full-circuit current without damage. IE: If you draw all 15A from a single socket, your house shouldn't burn down due to overheating wires and the socket shouldn't melt. Older homes (pre 1950s) may not be so generously wired. It is inherently unsafe to replace a (for example) 10A fuse with a 15A one (IE; replace any lower amp breaker or fuse with a higher rated one). This may cause excessive heating in the wires behind the wall and lead to a fire. Or it may just melt something, if not cause a fire. Always match amp ratings when replacing breakers or fuses!", "The way power in wall outlets work is kinda strange. It isn't designed to send a specific amount of power to a plug, instead its designed to send as much power to the plug as is necessary. Its hard to explain without getting into the physics behind it, but a simple view is how degices \"draw\" power. As you plug more things in, you draw more and more power from the main line (and in turn the power company produces more power to compensate).\n\nIn theory you could plug in as much as you want so long as the power company keeps up with the demand, but one pratical limitation is that wires melt when you pass enough power through them, so we have safety measures (fuses, breakers) that cut the power connection if it gets to be too much" ] }
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55csc4
why does the english language have a soft "r" sound ?
As far as i know most other languages have some sort of a hard "r" (most slavic languages , spanish , japanese etc.) . and even some English dialects . Is this a case of "just because" , or is there any other reason ? edit : thanks for all the good answers
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/55csc4/eli5_why_does_the_english_language_have_a_soft_r/
{ "a_id": [ "d89he7t", "d89l8lb", "d89l9mk", "d89lut3", "d89m4sc", "d89o993", "d89q8jp", "d89qehv", "d89rcpr", "d89v57v", "d89wyyz", "d89x4tf", "d89ycu4", "d8a4lkn", "d8a69va", "d8a7kt4", "d8a87st" ], "score": [ 2141, 52, 99, 33, 114, 162, 56, 2, 38, 12, 2, 2, 3, 5, 5, 6, 294 ], "text": [ "By the \"soft R sound\", I suspect you mean what phoneticists call a \"postalveolar approximant\" (the American pronunciation) or a \"retroflex approximant\" (some British dialects). They're very similar (I can't tell the difference myself), the \"normal\" American way of saying \"R\".\n\nWhat you call the \"hard\" sound would be what's called an \"alveolar trill\", which is the technical word for a rolled \"R\" (when it's rolled at the *front* of the mouth). That's certainly true of Slavic languages and Spanish. Japanese actually has a slightly different sound which sounds to Europeans like something halfway between an \"R\" and an \"L\", although it varies from speaker to speaker. It's not really helpful to compare it with the other languages you mention, because it evolved separately and isn't actually the same sound. When westerners came to write Japanese using the Latin alphabet, they just chose \"R\" to represent that sound, although they could just have easily have chosen \"L\" instead.\n\nThere's no reason any two languages must have the same pronunciation for specific consonants. There's no law that says that all languages must have the same kind of \"R\" sound, or the same kind of \"H\" sound, or the same kind of any sound at all. As languages grow and evolve, and eventually break off from each other to form new languages, sounds change as well, as the normal part of how things evolve generally.\n\nDifferent languages have different ways of pronouncing \"R\", and there are often differences between different dialects within the same language. Off the top of my head I can think of at least seven: some rolled at the front of the mouth, some at the back, some like the British/American versions, even one that sounds like somebody with too much phlegm.\n\nSeveral languages do have the American \"soft\" R you describe, or something very much like it: Dutch is one of those, which is particularly interesting because Dutch and English are very closely related. My guess would be that the sound evolved in some West Germanic dialects before the ancestors of English and Dutch separated from each other.\n\nMy hunch -- I haven't looked this us -- is that the original sound was something like an alveolar trill, the \"hard\" sound you describe. This is pronounced by allowing the tip of the tongue to vibrate against the alveolar ridge, which is the part of the roof of the mouth just behind the teeth. If you're a bit lazy and can't be bothered to push your tongue all the way up, you change it into an approximant: so the English (and Dutch) way of saying \"R\" probably came about in the same way as most changes of pronunciations do: people being lazy.\n\nEDIT: Thanks for the gold.\n\nEDIT 2: Cut out a bunch of irrelevant technical terms to make it more ELI5.", "If I remember correctly, our R comes from the R in Germanic languages which is articulated more in the back of the mouth, than our standard American English, British English, or French R. It was most likely brought up further into the mouth with the influence of Norman, Norman French, and other influences on English (ie: Dutch and Frisian, which are other Germanic languages, are close linguistic ancestors of ours, and may have some influence on that)\n\nThat said, regional dialect may also have something to do with it. Here in Philly, we articulate L on the end of words (bowl, vowel, trill, etc) in the back of our mouths, near our throat. Its called the \"dark L\" and we practically swallow our tongues.\n\nReference: am a German teacher, and a linguist.", "I wouldn't say Japanese has a hard R. What they have is something between L and R, and it's not really hard like How R is in Spanish.", "All I know is that I'm glad English doesn't use a trill like Spanish does. I'm half Mexican and I can't do a trill. I've tried to make that rolling 'r' sound for as long as I can remember. I'm 35 now and at this point I do a uvular trill in its place. It doesn't sound as good as a trill off of the front of the tongue, but it does well enough to convey meaning.", "Japanese most assuredly does not have a hard \"r\". In fact their \"r\" is so light it is often confused for an L by Europeans when Japanese talk, and the Japanese often confuse the two letters when speaking English and other European languages. ", "In my native language, Punjabi, we have 2 separate letters, one for a \"soft\" R and one for a \"hard\" or \"rolled\" R. \n\nI don't think there's a particular reason why one sound is chosen over the other, but it is noteworthy that in the majority of languages see them as variations of the same sound, so I'd imagine it's just a matter of which sound them stumbled upon first. ", "There are a lot of comments in this thread that say Japanese has no hard R, and has something closer to an L, or something between an R and an L.\n\nIn fact it actually has none of the above. If anything it has a \"soft D\" which isn't a terribly technical description and sounds kinda weird until you discover how to make it.\n\nI lived and worked over in Japan for about 12 years and although I became fairly proficient in Japanese, I struggled for a number of years with the 'Japanese R' until one day I met a linguist from a local university who taught me the simplest trick to mastering the sound in minutes.\n\nImagine someone says something rude to you and you kinda lazily respond with something like \"for fucks sake, shuddup!\" - as English speakers when we tell someone to shut up, we blend the two words together to make them easier to say and it becomes more like shuddup. Try it and note the moment in the middle where you are pronouncing a kind of very soft D sound joining the words. That moment where your tongue ever so quickly flicks up and momentarily taps the roof of your mouth is what we refer to as the Japanese R. If you can isolate that sound, you've basically got it.", "What do you mean, look at Boston. The leave the r out completely\n\n\"I pa\"ked the ca\" in the pa\"king lot. \"\n\n\n", "I live in Boston, what is this R you speak of?", "I can prove this wrong with one phrase: ARE YOU RRRREEAADY TO RRRUUMMMBLE?!", "Wait, do you mean Why DOESN'T?", "You mean like idea(r)? Or like thoroughfare?", "Not for nothin', but Spanish has a soft r \"r\", and a hard r \"rr\".\n\nExample: pero = but / perro = dog\n\nJust sayin'..", "I could never roll my Rs, so if I grew up speaking spanish, would I be considered to have a speech impediment? ", "And here I am pronouncing 'R' like 'ore' (when speaking english ), are there other english speaking countries which stray away from the standard (pirate: yarrrrr! sound ) pronunciation other than Ireland?", "As a German I do find English area quite soft and feminine (no offense) in Germany the r is like a bloody war cry", "This thread is making me feel like a moron. In what words might I use a hard \"r\" vs a soft one? I only have one \"r\" sound, as far as I can tell." ] }
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1kaod4
when you're flying in a plane, because of how fast it's going, if you jump, why don't you get forced to the back?
I understand it's because you're moving with it inside of it, but very simply, why is that the case?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1kaod4/eli5_when_youre_flying_in_a_plane_because_of_how/
{ "a_id": [ "cbn0fnb", "cbn0iv1" ], "score": [ 11, 2 ], "text": [ "It has to do with Newton's First Law of Motion: \n\n\"An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.\"\n\nEverything in the plane; you, the seats, the air, etc is all moving at the same speed with no force acting on you in the direction. The plane has air resistance on the outside of it but since the air inside is moving with you it doesn't push on you.", "It's a matter of something called \"inertia\".\n\nWhile you're standing in a plane, your body and the air around you is matching the velocity and acceleration of the plane. When you hop up, you're not just going straight up relative to the earth, but you're also moving forward at velocity of the plane.\n\nLook at it from the perspective of an observer standing on Earth. That observer will see the plane moving forward at some velocity in pretty much a straight line. However, they will see your hopping motion as an arc; your legs are pushing you upwards relative to the Earth, but the plane is constantly pushing you forwards." ] }
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bmlcxn
why american schools force children to pay for their lunch?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/bmlcxn/eli5_why_american_schools_force_children_to_pay/
{ "a_id": [ "emxgrnw" ], "score": [ 2 ], "text": [ "They don't. They force the parents to pay for lunch. It's the same in other countries, it just comes in the form of taxes. FWIW, if a child doesn't have money they are given a sandwich." ] }
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22b8c1
is the "high beta fusion reactor" a big deal? it sounds like supertech but i have no frame of reference
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/22b8c1/eli5is_the_high_beta_fusion_reactor_a_big_deal_it/
{ "a_id": [ "cgl5lur", "cglmjfo" ], "score": [ 4, 2 ], "text": [ "*Beta* is a fusion physics term referring to how well you are containing the plasma in a magnetic confinement reactor. Beta is a ratio of the plasma pressure versus the strength of the confinement field. You need a beta < 1 in order to confine the plasma and make the reaction possible.\n\nYou want beta to be as high as possible, because any extra strength more than what you need to contain the plasma is wasted energy. However, in practice it's hard to reliably contain the plasma without having a large margin of error, that is, a smaller beta. Many experimental fusion reactors run at a beta of 0.1, meaning that only 10% of the magnetic field is needed, on average, to contain the plasma.\n\nIf you can reduce the margin of error needed, resulting in an increased beta, you can save energy on the containment field. The neat thing about the High Beta Fusion Reactor is that it will have, theoretically, a beta very close to one, which means it wastes far less energy on containment.\n\nI'm not a nuclear physicist so I can't say for certain how revolutionary that design is, but it apparently has a much faster development period over standard fusion reactors, which can take 30+ years to design and build. They plan on having a prototype in 3 years, with a production model 3 years after that. In comparison, [ITER](_URL_0_), another promising fusion reactor, will not be fully operational until 2027. ITER is an experimental design, and the production model, DEMO, won't be online until at least 2033. If the High Beta reactor sticks to it's schedule, it's very possible that fusion power will become a practical power source in < 10 years. I'd say that's pretty impressive.", "The high beta fusion reactor is a Lockheed Matin's Skunk Works project. The fact that Lockheed is now interested in fusion, and investing is fusion research is noteworthy. Like most Skunk Works project, very little has been released publicly about this project. With such little info is hard to say anything definitive.\n\nFrom what I have heard, it sounds like they are researching a field reversed configuration (FRC). FRCs have been around for a while. They are not new. The FRC has a number of engineering advantages, but at a cost. There are major gaps in our understanding of FRCs, and it remains to be seen how they will behave at reactor relevant conditions. \n\nFRC research is a worthwhile venture, but Lockheeds claims that they can develop a compact fusion reactor in 5 years is foolishly optimistic. " ] }
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[ [ "http://en.wikipedia.org/wiki/ITER" ], [] ]
9172n9
how do artists pay taxes when they have world tours?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/9172n9/eli5_how_do_artists_pay_taxes_when_they_have/
{ "a_id": [ "e2vtree" ], "score": [ 25 ], "text": [ "They owe taxes to each country they perform in. Since it is pretty easy to figure out what they made form each individual performance (since the number of tickets sold and the artist's cut are both known amounts) it is fairly straight forward to calculate their income earned at any given venue." ] }
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25jeps
what makes some people a "morning person" and others not? is it possible to become one?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/25jeps/eli5_what_makes_some_people_a_morning_person_and/
{ "a_id": [ "chhqg4q", "chhqj9y", "chhrase", "chhukfj", "chhv81v", "chhx21d", "chhxh93", "chhxlgz", "chhxsci", "chhz6ku", "chhzh12", "chhzops", "chi0m1g", "chi0mj4", "chi0njo", "chi1mpi", "chi2jnz", "chi2o3m", "chi2u9s", "chi3qcp", "chi5wup", "chi5z9i", "chid424", "chimb46" ], "score": [ 146, 12, 2, 2, 6, 78, 248, 4, 550, 2, 2, 2, 2, 2, 10, 2, 2, 2, 2, 10, 2, 2, 7, 2 ], "text": [ "yes. As I got older I became my father. I am now up by 6 all the time and get most everything accomplished before 9. It's amazing at the quiet and ability to get crap done before the day starts.", "It is probably due to your personal sleep cycle. ", "Not sure about being a morning person (that's mostly biology + age), but I know you can become a light sleeper by repeatedly having your alarm go off during the early mornings. 4 AM, 4:30, 5, 5:30, 6... after a few days of this you will not sleep the same. ", "It's all about melatonin!", "Just go to bed at like 11 and wake up at 6/7 everyday for a couple of weeks. Keep your blinds open so the sun wakes you up as well.\n\nThen before you know it, you will be fine in the morning. Also stay away from caffeine when you wake up.", "It's at least 50% hereditary according to sleep researchers, and no amount of trial, self-discipline, or compromise will change the inner clock. \nSource: Strawbridge et al, 2004. Impact of Partner's Sleep Problems on Partners. \n\nYou can however change your sleep schedule and reset your circadian clock by simply camping without electronics for a week. Otherwise you'll have to use discipline. You'll adapt to whatever sleep schedule you demand of yourself, but that won't mean you'll become a morning person (and all that that implies). ", "I hate waking up early. Tired eyes, stiff muscles, and a yearning for coffee similar to that of a junkie and his next fix. This is always worse the earlier I wake up, doesn't matter if I've had 10 hours of sleep or 3.\n\nThat being said I almost always force myself to get out of bed early. After that initial crappy \"wake up\" phase the early mornings are brilliant. The fresh smell in the air, the sun rise, birds chirping... And everything else is quiet. Not to mention it feels fucking awesome to get a shit load of stuff done before 11:00am.\n\nOf course this usually means I'm exhausted and ready for bed by 10:00pm. Yep, I'm 26 years old but purposefully maintain sleeping habits similar to a 60 year old because I like fresh air and birds.", "Buy a pair of blue-blocking sunglasses. Wear them starting at 6:30 pm. Take melatonin with dinner. First night or two, consciously try to be in bed by 10-10:30, but you should find yourself naturally doing that by the third day. If you can't take melatonin by 7-7:30 after that, skip it but faithfully use the sunglasses. Don't be afraid to look like a douche, you're just repairing your circadian rhythms. PM me on the 7th day with your eternal thanks.\n\nEDIT: you wear them from 6:30 until you are in bed in the dark. [I recommend these.](_URL_0_) This and melatonin will fix your sleep for about $50 all in.", "This might seem like a non-serious answer, but this is what I do and I assure you it works.\n\nBasically what I do is to take the Barney approach to waking up. As in, instead of feeling tired and shitty, just stop feeling tired and shitty and be awesome instead. It's all about learning to control your emotional state. Just give a big stretch, and put a giant shit eating grin on your face and say \"Good Morning\" out loud in your most annoyingly chipper and enthusiastic voice.\n\nI learned this technique when I was backpacking through Europe. When you're hungry and tired and your pack is too heavy and your idiot friend booked a hostel that's over a mile from the nearest bus stop, you can either be grumpy and miserable, or you can... not be those things.\n\nReally no other way to describe it. It's all about self control.", "Short answer, yes.\n\nHere are some tips I've found over half a military career. First of all, there is no substitute for practice, as in all things. The first day of waking up early *hurts*. Personally, I find that getting up before the sun is exceptionally painful, so start by waking up a few minutes after dawn, assuming you have the option.\n\nThe three best things to help me wake up are sunlight, oxygen, and water. Leave the blinds open if you can, or open them up immediately upon waking. You'll never be able to wake up is you stay in a dark room. Upon waking, immediately take several deep breaths. You've been breathing shallow all night - get your lungs full of air, and get the blood pumping. Get some sunlight into your eyeballs ASAP. It works like magic! Your body will instantly stop fighting against waking up.\n\nHydration is so important. If you're dehydrated when you go to bed, you'll be screwed in the morning. So guzzle a quart of water before bed. Hopefully you'll have the added bonus of a full bladder that won't let you stay in bed. When you get up to take that morning piss, guzzle some more water.\n\nIf you're a coffee drinker, get a pot with a timer and set it for your wake-up time. It's much easier to get out of bed when hot coffee is waiting for you.\n\nDuring the day, be mindful of things like caffeine intake, workouts, and eating dinner so you can get to bed on time.\n\nGood luck, OP!", "I don't know.\n\nBut leaving caffeine behind helped me become more of a \"morning person.\"", "TL;DR: try using lights on timers to wake you up instead of an alarm clock.\n\nOur biological clocks originally adapted to take the sun rising as the cue to wake up. This was the case for millennia. Similarly we are more adapted to sleep through or ignore noises.\n\nIn a past life I spent some time in jail where lights are on 24x7 and there are no windows to give day/night cues. I was able to function on much less sleep, getting up at 4am and being quite comfortable.", "Excellence is a habit. Just get used to it and eventually it will become routine.", "I turned into a morning person by making myself go to bed by 10:30pm. I wake up usually before my alarm (6:15am). The downside is I can't sleep in no matter how hard I try. ", "I have a sleep disorder called delayed sleep phase disorder (DSPD). For me this basically means that getting up in the morning is really, really hard. It would be like you (or a person with normal sleep patterns) having to wake up at 2 AM everyday. \n\nOur bodies have several biological rhythms or cycles. One of them is called the circadian rhythm and it's responsible for sleeping and waking. It's typically a 24ish hour cycle. There are changes that happen in your body during the cycle... Things like body temperature and hormone levels. Especially important is the hormone melatonin. It's responsible for the sleepiness you feel when your ready to go to sleep. \n\nSo the reason why you can change time zones and after a couple of days fall back into your normal sleep/wake times is that your body's circadian rhythm can \"reset\" itself because it responds to light stimulus. One of the most effective ways to wake up is to expose yourself to bright light. That basically tells your melatonin to gtfo and you can feel awake again. \n\nSo what makes someone a morning person? Genetics mostly. They determine how your body responds to stimulus. Some people are morning people (larks), some are night people (owls) and some are in between. It has been argued that there was an evolutionary advantage to this... A night watch sort of thing. It strikes me as a bit speculative though and I can't remember where I learned that so take it with a grain of salt. \n\nDSPD is where your circadian rhythm is so out of synch that being awake during \"normal\" times really fucking sucks. Additionally many people with DSPD tend to have a much harder time waking up when their body isn't ready to. So someone like me could probably never become a morning person. A normal person has a much greater chance of shifting their wake time though. Here are some tips:\n\n- Pick a bed time about 7-9 hours before you want to wake up. Dim all lights roughly 3 hours before bed time. \n- Roughly 45 min - hour before bed stop using screens. No phone, computer, or TV.\n- The bed you sleep in should only be used for sleeping and fucking. No hanging out in there. \n- Once you lay down to sleep, if you can't fall asleep within 30 minutes or so, get up and hangout in a different room. Keep lights dim. Read a book or listen to a boring podcast or something. No fun for you. After about 20 minutes try to go back to sleep. Repeat. \n- When you wake up in the morning, turn on ALL OF THE LIGHTS. Go outside if it's light out. Take a quick walk or something. \n\nDo these for a couple of weeks and you should be able to shift your sleep/wake times and feel pretty chipper in the morning. ", "I have this phrase as a life rule: \n\n\"The only thing that holds one from doing something is not doing it\"\n\n\nIt's fucking obvious to death.", "Waking up on a proper sleep schedule honestly. If you don't wake up in REM sleep, you are good to go.\n\n_URL_0_ ", "The military sure has a way of making morning people. ", "Why? because they interrupt their deepest point of the rem phase.\nHow to become one? Wake up at 1:30, 3:00, 4:30, 6:00, 7:30 etc hours of sleep and you won't feel as tired in the morning, you might even BOUNCE out of the bed like I like to call it.\n\nSource and calculator: _URL_0_ \n\n", "So, all mammals have a circadian cycle, which is a biological cycle that lasts roughly 24 hours, which leads to changes in your body throughout the day. Certain hormones are higher in the morning, activity levels are different, appetite changes, etc. This cycle is set off every day by light hitting the retina. This sends a signal to a part of the brain called the suprachiasmatic nucleus (SCN), which is the \"master clock\" of the body. That master clock sends signals to the rest of the body, basically saying, it's a new day, folks! Time to get going!\n\nThat being said, your body has it's OWN cycle. That light stimulus in the morning is a reset button to make sure that cycle is on track, but if you take it away, you'll still have a cycle that lasts about a day. This is found by putting a human (or animal) into continuous low light, continuous light, continuous dark, etc. Without that first morning light, called the zeitgeber, hitting the retina and telling your body to start the day, you start to free-run, or run on your body's own physiological rhythms. The length of one free-running cycle without a zeitgeber is known as T, or tau. Everyone's tau is a little different, most are slightly over 24 hours long but some are less. \n\nTake a look at this figure from Pilorz et al 2014 (_URL_1_) to see what I mean: \n\n[Figure 1](_URL_0_)\n\nJust pay attention to the top row. This is activity over 24 hours (double-plotted, so each row in the graph is two days of activity), with time on the X axis, each tick is an activity count. In the first graph, you can see that the animal is behaving pretty close to tau = 24; it's waking up and moving around at about the same time each day. The second graph is an animal with tau > 24; it's waking up a little bit later every day, so you see a positive shift in the activity. The third graph is an animal with tau < 24; it's waking up a little earlier each day, resulting in a negative shift. (There's a light shift in there as well, kind of like when we turn our clocks ahead/back an hour, but just ignore that, this is just an example.)\n\nSo let's take someone who has a T of 24.5. This doesn't seem very far off, but what it means is that every day, when your alarm clock goes off at 6AM, your body thinks you still have half an hour left before you're supposed to be awake. This makes you NOT a morning person, you're constantly trying to play catch-up with the clock. Someone with a tau of 23.5, however, will be able to wake up just fine, might even be up before the alarm, because their body is telling them the day already started.\n\nIt's certainly possible to become a \"morning person\" through behavioral means, like just going to bed earlier, or by reducing light exposure in the evenings, but there isn't any scientific evidence that you can change your tau. If your tau is over 24, you're always going to have a tough time getting up. Sorry.", "Some people are just assholes and take out being groggy in the morning on other people.", "I use _URL_0_ to calculate when I need to go to bed for my wake up time. Waking up in between sleep cycles is not fun! \n\n(I also programmed my coffee machine to start making coffee when I wake up. Coffee smell = best morning energizer) ", "Morning people are possessed by the devil. I though everyone knew that.", "I can't answer the difference, but I'd say yes. I've gone through phases in my life where I absolutely *love* getting up early, taking in the sunshine and going out into the garden to water the plants and soak up some rays with a coffee and a cigarette. \n\nOn the other side of that, I'm a night person and I love being up all night. I love the peace, I love the stars - it's beautiful. \n\nI just wish I could somehow freeze time when I slept and didn't have to have 5 meals a day to make up for it. I love mornings and nights but because I do a lot of work at night I don't really get to appreciate the morning that much anymore. When I was a teenager and early 20s I hated waking up early but as a kid I was up at the break of dawn to watch cartoons and eat breakfast. Now I want both but I can't freaking have it, it sucks !" ] }
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[ [], [], [], [], [], [], [], [ "http://www.amazon.com/BluBlocker-Official-Eagle-Sunglasses/dp/B00DE0NBCW/ref=sr_1_4?ie=UTF8&amp;qid=1400092441&amp;sr=8-4&amp;keywords=blublocker+sunglasses" ], [], [], [], [], [], [], [], [], [ "http://sleepyti.me/" ], [], [ "http://sleepyti.me/" ], [ "http://www.cell.com/cms/attachment/2012661307/2034840365/gr2_lrg.jpg", "http://www.cell.com/current-biology/fulltext/S0960-9822(14)00195-X" ], [], [ "http://sleepyti.me/" ], [], [] ]
5uvuoi
why do we cringe when we see someone bite a fork and pull it through their teeth?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/5uvuoi/eli5_why_do_we_cringe_when_we_see_someone_bite_a/
{ "a_id": [ "ddx8qg3" ], "score": [ 2 ], "text": [ "I cringed just thinking about it. But if I had to take a stab at your question I would have to say it's because I feel like teeth are a fragile part of our mouth. When I see/hear things rubbing up against them it just gives me the shivers." ] }
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16pe5r
cosinus, sinus, tangens and cotangens.
As the title says...it's really as simple as that....I don't get it.
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/16pe5r/eli5_cosinus_sinus_tangens_and_cotangens/
{ "a_id": [ "c7y40gx", "c7y414v" ], "score": [ 5, 2 ], "text": [ "Isn't it sine, cosine, tangent, and cotangent? \n\nThey are called trigonometric functions. I am certain they have pretty good, intuitive explanations of what trigonometric functions are all over the web!", "They are trigonometry functions. Trig = triangle. Nometry = measure.\n\nIn simple terms, trigonometry is the science dealing with triangles (YAY!) and cosine, sine, tangent along with cosecant, secant, and cotangent are trigonometry functions.\n\nI'm sure you are aware of what right triangle is but just in case you don't, imagine a triangle where one of the angles inside is exactly 90 degrees. The other two angles can be anything as long as they all meet to form a triangle.\n\nNow. The side that is directly opposite of the right angle is called the hypotenuse (the longest side). Now pick a corner that is not the 90 degrees and the side that is not touching this corner is called the opposite. The remaining side that is touching your corner is called adjacent.\n\n\n\nSine is simply a ratio of opposite side over the hypotenuse\n\nCosine is a ratio of adjacent side over the hypotenuse\n\nTangent is a ratio of opposite side over adjacent side\n\n" ] }
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1qohxv
how does the theory of biocentrism prove there is an afterlife?
Quantum physics, though the theory of Biocentrism, proves that there is an afterlife. Quantum physicist Robert Lanza said life creates the universe, and not the other way around. He argues that time and space don't exist in a linear fashion, proving it through the double-slit experiment. Here is where I get confused, "and if time and space aren't linear, then death can't exist in any real sense either". What does this mean and how did he jump to that conclusion. I don't have a formal background in physics yet I find this concept intriguing. Please ELI5
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/1qohxv/eli5_how_does_the_theory_of_biocentrism_prove/
{ "a_id": [ "cdeu8fh", "cdeud27" ], "score": [ 3, 2 ], "text": [ "I'm assuming that this post from a few hours ago is about the same topic: _URL_0_\n\n\nSummation of the answer: He is crazy and making stuff up.", "It doesn't. \n\nYeah, that's it. " ] }
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[ [ "http://www.reddit.com/r/explainlikeimfive/comments/1qngxb/eli5_this_article_on_quantum_physics_proving/" ], [] ]
2bfrel
how they get water in spacecraft? for astronauts and plants
If they drink urine then re gain water again.. but what for plants? if function of plant to produce O2 from Co2, then how they get water?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2bfrel/eli5_how_they_get_water_in_spacecraft_for/
{ "a_id": [ "cj4w3hr" ], "score": [ 4 ], "text": [ "The water is brought up from the ground. Any water that isn't absorbed by the plants will evaporate and be picked up by a system that harvests water from the atmosphere of the spacecraft. This water, just like the urine produced by the astronauts, will be recycled into the system." ] }
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2h2y1s
why does apple juice give me 120% dv of vitamin c?
Isn't 100% enough? *edit* So, what if I drink 5 servings throughout the day? Isn't there a point where I'm doing harm by drinking apple juice with so much vitamin C?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/2h2y1s/eli5_why_does_apple_juice_give_me_120_dv_of/
{ "a_id": [ "ckovxz2" ], "score": [ 3 ], "text": [ "Your body can use the extra. The dv is just sort of a minimum to stay healthy set by the fda" ] }
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161y4e
why is parallel communication slower than serial communication?
I'm talking about PATA and SATA. Wouldn't parallel be faster because it is sending multiple bits across separate wires?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/161y4e/eli5_why_is_parallel_communication_slower_than/
{ "a_id": [ "c7rxtar", "c7rypiz" ], "score": [ 3, 4 ], "text": [ "PATA is older technology than SATA. The path is wider with PATA, but the frequency is *much* slower.", "It's not just that serial is a newer technology. Serial is faster for a technical reason: parallel requires synchronicity, and that means you can't send information as fast as you want.\n\n**HAPPY METAPHOR TIME!**\n\nImagine the fictious kitchen of a burger joint. The kitchen will receive orders in the form of three messages: burger, side dish (fries, salad, whatever) and drink. Let's say the communication is slow and they can only receive one message every minute. With a serial setup, it takes three minutes to receive every order: first they get the burger, one minute later the side dish, and another minute for the drink (then another minute before the next order).\n\nTo improve it, they go with parallel: they install three order channels: one for burgers, one for side dishes, one for drinks. This way they can receive one order every minute. Parallel is faster!\n\nNow, consider that these channels are synchronized so that, when the three orders are sent simultaneously, they will arrive to the kitchen within 5 seconds of each other. That means, if for example a side dish comes up, within five seconds the burger and drink will also come up, so there's no problem telling what goes in what order. But you can't guarantee they'll get any closer than 5 seconds because of natural factors in the way messages are transmitted (they take different paths and are slowed down differently).\n\nSee where I'm getting at?\n\nLater the technology improves and they can send orders every 30 seconds. Still fine. No problem telling the orders apart. But say technology still improves, and they can send orders every five seconds. Now things are confusing: you received a fries order, and four seconds later a burger order. Does it go with the fries or is that part of the order after that?\n\nSo they are forced to slow down. Even though they can send orders every 5 seconds, they only send them every 10 or 15 seconds, just to be sure that the kitchen can match the right components. If technology progresses and they could now send orders every second, they still need to keep that 10-15 seconds delay or they will mix orders up.\n\nThat's when going back to serial will be faster: with just one channel, you're guaranteed that the orders are matched: you will get burger, then side dish, then drink, no matter how fast. If you can send orders every second, it'll only take three seconds per order. It doesn't matter if an order is slowed down by five seconds, as it will still come in the right order (if the burger is 5 seconds late, the side dish will still come after the burger, as it goes through the same channel). Now serial is faster!\n\n**tl;dr:** With serial, no matter what happens to your signal, it will happen to the whole signal, so going very fast doesn't scramble your information. With parallel, different things can happen to the different signals, putting them out of sync if you go too fast. Mmm, burgers!" ] }
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38c188
why doesn't our natural survival instinct kick in against thoughts of suicide in some people?
explainlikeimfive
http://www.reddit.com/r/explainlikeimfive/comments/38c188/eli5_why_doesnt_our_natural_survival_instinct/
{ "a_id": [ "crtyn1e" ], "score": [ 8 ], "text": [ "It does.\nI tried to kill myself twice (the second time was exactly 10 years ago today, yay!) and both times I had great difficulties to actually do it because of survival instinct. I foud it very unnatural and had to fight the fear to actually do it." ] }
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a175da
why are there a lot of ww2 movies and almost no movies about ww1?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/a175da/eli5_why_are_there_a_lot_of_ww2_movies_and_almost/
{ "a_id": [ "ean8njv", "ean8y70", "ean9ek2", "eanafxz", "eanalas", "eancr11", "eant7qt" ], "score": [ 26, 58, 11, 9, 3, 10, 2 ], "text": [ "Trench warfare fought for no sensible reason, doesn't make for good movies when you compare it to something like WWII where you can easily create \"good guys\" and \"bad guys\" combined with lots of machines of war like tanks, planes, subs, etc...along with a wide variety of environments ranging from North Africa to Japan. Best of all the \"good guys\" win in the end and everyone lives happily ever after. Of course, the reality is much different and complex, but movies aren't good at complex, so they tend to simplify everything to its most basic level. ", "There was widespread opinion after WW1 that it shouldn't have happened, and accomplished nothing. Its causes are still a bit hard to understand, and it discredited pretty much every government involved in it to one level or another.\n\nAnd while it was happening, the horror was ironically uneventful. People died in droves, but not much changed - the front lines did not advance much for most of the war. People might unknowingly clamber over multiple layers of buried corpses trying to capture the same few meters year after year.\n\nWorld War 2 was very different. It was one of the few wars in history that can be legitimately called *totally* unavoidable, given the mentality on one side. Its causes were clear, its moral distinctions eventually were found to be absolute, and its events and movements were very dramatic.\n\nIts outcome was also economically and politically profitable to the country that houses Hollywood, so lots of movies about it were inevitable.", "If you're in the United States, it's because WWI wasn't a significant influence on culture or industry here. We chose to engage in that war because we heard terrible things - that babies were being murdered in their cribs and such. Then we get involved and found out it wasn't true. But after WWI, we did what we always did in peace time, we sold off all our military inventory, because what good is a gun in a time of peace?\n\nWWII was the beginning of the modern American era. It dragged us out of a depression, and kicked off an industrial revolution of sorts, rife with innovation unseen before. Then, because the rest of the world was literally in ruins, and we were the only manufacturers left on the planet, we had an economic boom we're still seeing the effects of. So much of our culture and industry and motivation and politics trace back to that era, and not the great war before.\n\nAlso appreciate that we didn't have \"talkies\", or sound film in WWI, and the film and movie industry was little more than a novelty back then. By WWII, cinema was an industry and an art form, and a conveyer of culture and ideas. We were able to cement and spread the cultural impact of WWII throughout society as couldn't be done before.", "WW1 was a terrible grinder of men and material, much of it isn't that cinematic or \"epic\" for story telling purposes.\n\nThat said, we've recently had War Horse and Wonder Woman, both sent in WW1\n\nThere are quite a few Turkish films about WW1 - 6 in the last 10 years", "There are plenty of movies set in WWI. Just off the top of my head, I can think of *Gallipoli*, *The Lighthorsemen*, *All Quiet on the Western Front*, *Dawn Patrol*, *Lawrence of Arabia*, *War Horse*, *Sergeant York*, and *The African Queen*.\n\nCertainly the limited US involvement in WWI, combined with the greater number of movies filmed in the wake of WWII means more movies, but WWI movies do exist, including some highly regarded ones.", "Several reasons.\n\n- WW2 was bigger than WW1.\n\n- WW2 was far more important for the US than WW1. During WW1 the US was the 5th more important Ally with a bit more than 4 millions men. During WW2 the US was the most important Ally with 12 millions men (on par with the URSS).\n\n- WW2 is the easiest war to see as hero vs villain. It was liberating democratic countries vs conquering and genocide. For WW1 there was not a good vs bad guy. The causes of war was for the balance of power and sphere of influence for the political gain of the elite. \n\n- The violence of WW2 had more movement, more diversity and is overall more exiting to see on screen. You had tank penetrating the lines, you had Airborne Infantry dropped behing ennemy lines, you have Marines storming beach, you had pilot dogfighting in the air or dropping bombs, you had submarine chasing convoy, aircraft carrier fighting over Island in the pacific, etc. For WW1 the vast majority of the fighting was static in trench when wave of men were slaughter by poison gas, artillery or machine gun. \n\nWW1 was more dynamic on the Eastern Front, but the US were most of the movie come from, they didn't fight in the Eastern Front.\n\nTLDR : WW2 movie are more popular so they make more of those.", "I think thus far no one's answer has touched on one of the big key factors in WWII being so popular- we have a HUGE number of film recordings from it. The military was just figuring out that putting cameras on everything was a really useful idea for gathering information of all sorts, from gun cams in planes to flight operations on deck of aircraft carriers.\n\nWWII is quite possibly the best documented war in history." ] }
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64gjip
why they need to ask for objection in a wedding?
explainlikeimfive
https://www.reddit.com/r/explainlikeimfive/comments/64gjip/eli5why_they_need_to_ask_for_objection_in_a/
{ "a_id": [ "dg1z4yb", "dg1zb0b" ], "score": [ 4, 4 ], "text": [ "It isn't asking for anyone's *personal* reasons. It's asking if anyone knows of any *legitimate legal* reason that the two should not be married (for example, if someone knows they're actually related, or that one of the two is already married to someone else, or that one is actually underage).", "It's tradition, and these days they *don't* say it most of the time.\n\nThe original intent was to give people the opportunity to speak up about the *legality* (or adherence to religious requirements) of the marriage. To quote [another website](_URL_0_):\n\n > In the bygone days of charlatans, swindlers, elopements and bad record-keeping, \"speak now or forever hold your peace\" was a last-ditch effort to bring to light any illicit shenanigans that would nullify a wedding in the eyes of God. According to the Canon Law of the Catholic Church, impediments to a marriage include either the bride or groom being married already, having made a vow of celibacy, being underage, having been kidnapped or forced to wed, not being baptized, being incapable of having sexual intercourse, or having killed the other's former spouse. There are also stipulations about how closely a couple can be related by blood, marriage and adoption.\n\nBasically, the intent is to bring to light some reason that the two cannot legally or religious be married, to prevent their going through with an invalid ceremony and disgracing the church." ] }
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[ [], [ "http://www.livescience.com/22193-wedding-marriage-objection.html" ] ]