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9vnrik | if an underage person were to have non-consensual sex with a legal aged person, and the person of legal age was the victim, who would get in trouble? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9vnrik/eli5_if_an_underage_person_were_to_have/ | {
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"The person who committed the rape would be legally responsible because the older person did not give consent. \n\n_URL_0_"
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37qkzi | why movies obviously photoshop the faces of the cast on "family" pictures that they could of easily just taken pictures of? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/37qkzi/eli5_why_movies_obviously_photoshop_the_faces_of/ | {
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"Well you can pay some low level photoshop monkey $15/hour to do the work on this in like just an hour, or pay for an entire photo shoot, actors, photographers, make up people, lighting and such, which can easily be in the tens of thousands of dollars and take a whole day.\n\nOr just pay that guy $15 and have it done in an hour."
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41a091 | if i developed my own spaceship and went to space and killed someone...how would i get in trouble and by who? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/41a091/eli5_if_i_developed_my_own_spaceship_and_went_to/ | {
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"My reading of the international space treaty seems to indicate that your country's government bears the responsibilities for your actions in space, so most likely you would prosecuted under your own nation's laws. If your country is willing to extradite (if needed) to the country of the person you killed, then their laws probably carry weight as well \n\n_URL_0_"
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4edri7 | how can the new video game "no man's sky" have over 18 quintillion (1.8×10^19) planets, while other modern games can't even load exponentially smaller sized maps? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4edri7/eli5_how_can_the_new_video_game_no_mans_sky_have/ | {
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"It doesn't/won't actually have that. It's just a technical possibility based of the formulas they use.\n\nFor example there are: 80,658,175,170,943,878,571,660,636,856,403,766,975,289,505,440,883,277,824,000,000,000,000 ways to shuffle a deck of cards. Obviously, you can see that's not happening.\n\nMarketing!",
"Because those planets will be procedurally generated and not all loaded at once. Minecraft's world map is hundreds of times the surface area of Earth, but it isn't all loaded or even generated at once."
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1j3d38 | when and how did banks switch from actual paper money to the computerized system they use today? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1j3d38/eli5_when_and_how_did_banks_switch_from_actual/ | {
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"Banks have always dealt with \"virtual\" money, that is money they own but that they don't hold in their hands. The first banks were merchant banks. These banks helped merchants with their business. Instead of having to carry gold around merchants paid each other with paper notes. Imagine a Flemish merchant that received a note from an Italian merchant and went to his bank in Bruge. He handed over the note and now his balance increased. The Italian bank had already decreased the balance of the Italian merchant. But the gold didn't need to move. Occasionally banks could transfer gold if the balance between them became uneven. But moving gold around is not easy so banks tried to avoid this. Computers made this system more practical but the system had already been in place for centuries.",
"The computerized system they use today is only a recent thing. Banks were slow to adapt to new computer technologies. At the turn of the century Washington Mutual was still using OS/2 as their platform. In the mid-90s they were still using text based software.\n\nBut banks have used computers since the 1950s. Bank of America created ERMA with the help of Stanford to do their accounting. MICR (magnetic ink character recognition) was invented as part of that project. Since then banks have used more and more computers to track as much of their information and do as many of their calculations as they can.\n\nI recently saw a presentation of the latest diebold machines and ATMs can now do pretty much everything people need. And we will probably start seeing more and more ATMs spitting out more than just 20 dollar bills but able to give you 10s and 5s and even 1s in what they call recycled money machines.",
"Banks have never really dealt with actual money. They take your paper cash, write down in a book that they have $100 of your dollars... then loan $100 to someone else.\n\nThe bank now has 0 dollars on hand. It owes you $100. Some other guy owes them $100.\n\nThey make money because the bank told you it would give you $5 if it could have your $100 for a month. It told the other guy it could have $100 if the guy paid them back $110 in a month.\n\nAt the end of the month, if the guy pays it back and you want all of your money, the bank has $5 more than it did before all this started.",
"Before computers, banks kept the customer accounts on paper. \nIn most cases, in the 1970s, they moved from those paper records to computer records, which tellers accessed from terminals.\n\nIn the same time they invented the ATM, which took the teller out of the equation, letting the customer directly access the terminal, and deposit or withdraw funds. In the 1980s they networked the banks and ATMs, so you could access your funds anywhere. They also developed POS terminals, so you could buy things directly from your bank account (in Canada and other places at least). ",
"No expert on the subject but quite familiar and interested in the banking system so I'll try to explain it as simple as possible.\n\nThere are a few concepts that I will introduce for better understanding and clarification. You can Google or Wikipedia these terms for in-depth explanation of them.\n\nWhat you refer as paper money is what is known as Fiat Money and its origin even dates back to 11th century. Today, the most widely used fiat currency are bank notes like the US Dollar, Japanese Yen, etc.\n\nIn regards of computerized system, I will assume that you are referring to electronic banking of transactions and book entries. \n\nAs far as I know, the banking system earliest use of electronically sending data in and out is during the late 70s using terminals known as Videotex (Minitel used to be the trade name of one of the most popular).\n\nWhile banks do have fiat money originated from deposits, transfers, etc.; not all is kept actually in the bank reserves. This practice is known as Fractional Reserve Banking where only a portion of the total deposits are actually held in the bank reserves.\n\nEvery time a deposit or a withdrawal, or any other transaction is made, a book entry is created and computerized systems makes the executions of all these entries more efficient, speedy and accurate.\n\nOther concepts that are related to the subject are the Bretton Woods System, the Nixon Shock, FDIC (created to prevent Bank Runs which is one of the risks of Fractional Reserve Banking).\n\nOne interesting side note is that the end of the Bretton Woods System and the Nixon Shock implementation contributed (and I am paraphrasing here) to successfully tax the world as the most powerful economic countries in the world decided to adopt the US Dollar from the Gold standard."
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aofazm | during a siege on a castle, why didn't defenders make more stone walls behind the gate? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/aofazm/eli5during_a_siege_on_a_castle_why_didnt/ | {
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"What?\n\nBecause it's a gate. it doesn't work if you brick it up.\n\nAlso: do you know how slow building castles was? They didn't have time/materials to quickly build a wall in the event of a siege. \n\nAlso, it's nice to go outside. And maybe have a counterattack, or emissary going in/out. Or leave after the siege ends. ",
"There are several enhancements which protected the gates:\n\n- A drawbridge, a bridge made of thick wooden planks which was pulled in front of the gates.\n\n- An iron portcullis, which was slided in front of the gate which strengthened it.\n\n- Yetts, which are hung behind the gate.\n\n",
"Because in the vast majority of cases the construction of the gate defenses was sufficient to discourage an attack. Assaults were exceedingly rare. Really for castle defenders the threat was starvation, not the enemy getting in. Most castles were small, local fortifications, and couldn't sustain a long siege anyway - in that case the defenders would usually surrender after a few days of symbolic resistance. ",
"Lack of room, materials and manpower.\n\nBuilding fortifications isn't easy and you don't make them bigger than you need to. Building inside fortifications would require you to tear down some of the stuff already there to make room and get building materials.\n\nYou won't be able to get all the materials you might need to build a good wall anyway (like wood from trees) and the people inside who were living in the buildings you are tearing down might object.\n\nAlso during a siege you tend to be generally short on everything including food. Making your people engage in hard work like building walls, while food is already rationed is not a good idea.\n\nIt makes much more sense to build your fortifications correctly before you need them rather than try to improves during a siege.",
"\n\nThere's a story about Ghengiz Khan (no idea if it's true). He had a method of psychological warfare to resolve sieges. When his horde arrived to besiege a city, they'd put up a white tent.\n\nWhile the white tent is up, a city can surrender and all of it's citizens can leave unharmed. After which the mongols plundered the city.\n\nWhen Khan's patience ran low, the white tent is replaced with a black tent. If the city surrenders, the Mongols will kill every able bodied man in the city. But the women and children are free to flee.\n\nIf the black tent doesn't work. It is replaced with the red tent. The Mongols will kill every living thing in the city and raze the city until not a single stone is left upon another stone. The debris will be buried and the earth salted until there is no sign left that there ever stood a city.\n\nSupposedly the Khan only had to raise the red tent a few times and never again.\n\nSieges are political tools. It means the attacker cornered the defender. And unless there's a very dire reason to assault (can't afford to maintain the siege, defender's allies are on the way etc.), there's no reason to asasult.\n\nSimilarly, people tend to be very short on mercy after you spend a few days hosing them with boiling oil and pushing them off 40ft ladders. Unless the defenders are extremely confident they'll pull through, it's often not a great idea to antagonize besiegers too much."
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1gtzgp | what is lossless audio? | I hope to understand .FLAC file type and what the real distinction is. Thanks | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1gtzgp/eli5_what_is_lossless_audio/ | {
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"Lossless audio compression doesn't lose any information. If you compress a 100MB .WAV audio file to about half its size in a FLAC file and decompress it once again, the decompressed file will match the original uncompressed parent file exactly. Lossy audio compression discards information, so if you decompress an .MP3 file it will no longer match the parent file it was created from. It will be \"simpler.\" Depending on the compression level used an the ability of the listener, this \"simplification\" will be detectable as audio artifacts.",
"Most types of audio files are compressed in order to make the file smaller. FLAC files are not compressed*, which is why they have better sound quality. Compression is a fancy way to try to recreate the same file, but use less data to do it.\n\nIt's sort of like what happens when you take a picture, shrink it down, and then blow it back up again, like [this](_URL_1_) and [this](_URL_0_). What happened is that shrinking the image down reduced the file size, because there are fewer pixels. However, if you blow it back up to the original size, there was a loss of detail, which is why it looks bad. There's less overall data in the grainy picture.\n\nThe same thing is done with audio. The way they do the actual compression is *much* more elegant and complicated than what I just did with the picture, but the basic principle is the same; you're losing detail (fidelity in audio terms) in exchange for a smaller filesize.\n\nNow, for most people, the difference between a high-quality MP3 and FLAC aren't noticeable, which is why the format isn't very popular. Almost all audio devices/software can handle MP3, whereas you have to use special stuff for FLAC. Finally, and perhaps most important, most people don't have speakers/headphones that are good enough for it to matter. You can have the cleanest input in the world, but if you send it through a speaker that isn't top-end, it will be completely impossible to tell it apart from a slightly compressed input.\n\n*technically, FLAC files are compressed, but the compression is lossless, as opposed to other audio codec compression methods, which are lossy. explaining lossless compression is not particularly important here.",
"Imagine a \"condensed\" version of a book. You still get into the story and characters and everything and unless you are paying a lot of attention you won't miss several details. But in the end you still enjoyed the book. That's MP3. Some music details are lost, but unless you have very good ear and very good sound equipment you won't notice the difference.\n\nFLAC is word by word the same version of the book as how originally the author write it. Is longer and may have some boring parts here and there but some people like reading the whole book.\n\n"
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4bf728 | how do microfiber cloths work? | Also, why do they clean better than, say, a regular cloth or wet paper towel? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4bf728/eli5_how_do_microfiber_cloths_work/ | {
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"Microfiber cloths are cloths of a synthetic material of woven fiber finer than a silk thread. This makes it so the cloths won't deposit large fibers like other cloths do when they are used to wipe a surface. This makes them useful for cleaning delicate components where residue would be damaging. It also makes them effective cleaning cloths in general as unlike other cloths and papers towels they won't leave large residue 'chunks' formed of dirt being wiped and lost fibers/pieces. They also pick up less of these 'chunks' and can be cleared of them more easily. Overall they have their useful traits because they're composed of thin fibers that form a less permeable material that gives off large residue less easily. "
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dhbs8h | how does paint thinner work when mixing paint and why can't we just use water/etc? | Title, basically | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dhbs8h/eli5_how_does_paint_thinner_work_when_mixing/ | {
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"There are paints that do use water.\n\nIt all depends on the makeup of the paint.\n\n[Thinner](_URL_3_) is a solvent -if you put brushes made of the wrong material (e.g. plastic into a thinner for [oil-based paints](_URL_1_) ) into a jar of thinner, they start to melt.\n\nThinner does just that - makes paint \"thin out\" so you can work with it. When I was a youngin' I did build some plastic models and sometimes the paint was like molasses. Some thinner would make it easier to paint. \n\nSince it's a solvent, a rag soaked in thinner is used to clean up the mess and soaking a brush in thinner is a way to clean it (but see above).\n\nFor oil-based paints, water won't work as it's literally \"oil and water don't mix\". [Acrylic paints](_URL_0_) require their own thinners, but use water for clean up. \n\nSome applications may require thinner because the paint may be too thick to do the job. An [Airbrush](_URL_2_) may require paint thinned to a certain mixture in order to work. Tap water contains micro-organisms that could foul the spray mechanism."
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5s1jol | what is it about potatoes that makes them go so well with so many different foods? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5s1jol/eli5_what_is_it_about_potatoes_that_makes_them_go/ | {
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"Watch this short informational video about potatoes, it will clear everything right up. Potatoes are really amazing \n_URL_0_",
"Potatoes are have a relatively neutral flavor. This means they can take on the flavors of other foods without greatly disrupting the flavor profile. They're also cheap way to add bulk and calories to a meal. Recall that calories are only a bad thing in societies and ages of affluence. In times and places where food is scarce, the goal is to get as many calories as you can into a meal because you don't know whether you're going to eat well next time. Even though we may not have such problems in some places today, it's still why the potato became an integral part of various cuisines in the first place."
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psas1 | why it matters if a species like the tiger goes extinct | I think they're beautiful animals and it would make me very sad if they all died out. But from a scientific standpoint, what impact do they have now as it is? And how would that change?
Edit: Thank you for all the answers, I really appreciate it. I could have been more specific, but some of you read my mind anyway. What I'm really getting at, is that I know it's sad whenever a species dies out and we should do whatever we can to stop it. But with an animal like a tiger where there are so few left, what's the scientific reason to save them? Carry on. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/psas1/eli5_why_it_matters_if_a_species_like_the_tiger/ | {
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"I answered [the same question for pandas a while ago](_URL_0_):\nBiodiversity is good. Having a lot of different types of plant and animals ensures that nature, and thus humanity, has options. What if something happens to kill all the cows and pigs, but makes pandas breed like crazy. Well then we'd use pandas for food and be glad they didn't go extinct back in the 21st century.\nThat is a selfish human reason. Nature needs biodiverstity to allow for extinction. Some plant seeds can only germinate when eaten by an animal and passing through their digestive system. So, if you lose the animals that eat the seeds you need some other animal to move in and take up the role. If none exist, the trees all eventually die. Then the bugs that eat the leaves die. The animals that eat the bugs die. Without backups for food supply and for population control you end up with total ecosystem collapse. \nThis is also why everyone is afraid of the loss of honey bee colonies. They are the sole pollinator of large scale agricultural crops. No pollination means no fruits and vegetables, which means no food.",
"Imagine a garden with 3 species - ladybugs, aphids, and strawberries. Ladybugs spread slowly, and eat aphids. Aphids spread quicker, and eat strawberries. Strawberries spread very quickly, and only need sunshine. Normally, there is a balance. Ladybugs will eat enough aphids so that the aphids can't eat all of the strawberries. The numbers of ladybugs and aphids and strawberries remain roughly stable, year after year. (I won't get into predator prey cycle)\n\nImagine, however, if all the ladybugs in the garden were killed off. This is great for the aphids! They can expand and have more and more babies. This isn't so good for the strawberries, and soon they are eaten. This is now very bad for the aphids because they have nothing to eat! They starve and all die. \n\nJust by removing one part of the garden, we've destroyed the whole thing.\n\nSimilarly, a tiger **(edit: I was thinking lions for some reason, I know tigers don't live near zebras and antelope)** is the apex predator anywhere there isn't people. You remove them, the antelope and zebras and deer get overpopulated, and they eat too many plants, and turn the savanna into desert. (This isn't the only, or even the most major cause for desertification, but I'm simplifying things here)",
"The balance of nature and the domino effect. The tiger might be preying on various herbivores. If one of those populates unchecked it may wipe out various plants. One of those plants may hold the key to cure cancer, AIDS or some future illness. That is just one of countless possibilities.",
"Here's one reason explained to me before. Millions of different species have become extinct over the course of history. Really, one more isn't a problem. That's just how it goes. The problem, though, is that with human intervention we have prevented another species from replacing the extinct ones. Normally when one animal goes extinct for whatever reason, another species has generally been able to cash in on that opportunity. Yes, the biosphere changes to suit the needs, but that is still how it goes. Human industrialization has prevented new species from becoming dominant in place of extinct ones.",
"To add to what has already been said, there are a lot of animals that have biological processes that we can learn from, especially animals that aren't researched as much. Nature does a lot of things that we wish we could do (lizards regrowing limbs for example). While a tiger is probably not an animal that we can learn much more from, there are many undiscovered animals in the rain forest with unique qualities that we could possibly learn from.",
"I think this will explain it best for you. [Here is a story about the St. Matthews Reindeer herd in comic form](_URL_0_)",
"What is man without the beasts? If all the beasts were gone, man would die from a great loneliness of the spirit. For whatever happens to the beasts, soon happens to man. All things are connected.\n-Chief Seattle (falsely attributed, but the words are still meaningful)",
"From a scientific standpoint, would you risk Attenborough stopping by your house to beat the crap out of you?",
"Access to a large gene library is beneficial to applications of genetic engineering. If the tiger has a gene that could protect humans from cancer, we don't want it to disappear.",
"Most of these answers are incorrect if you're talking specifically about tigers.\n\nAlthough tigers are indeed the apex predators in their environment, there are only ~3000 individuals remaining in the wild stretched across all of Asia . Unlike alligators that dig canals or elephants that knock over vegetation, tigers also have relatively little impact on their environment. If these animals were to die, the effect on the ecosystem would be minimal, unnoticeable to the average person.\n\nThe reason why it is so important to keep tigers around is because they are so majestic. Like giant pandas and polar bears, tigers are a powerful symbol of conservation and serve as ambassadors to the general public. If tigers went extinct, we would lose more than a cool animal. ",
"Imagine how amazing it would be to re-create a dinosaur and have it walk around. Imagine the marvel, the sense of awe...\n\nWithout heroic-level efforts to preserve a species, our children would have this same sentiment towards thousands of species, tigers just being one of them.\n\nAll that being said, [this](_URL_0_) is a far better answer",
"Because they're awesome.",
"Sadly, not all animals are \"important\" for lack of a better word. Many species have gone extinct without throwing the world out of order. for example, the [passenger pigeon.](_URL_0_) It was once one of the most populated bird species and now it's gone and nothing terrible (not to sound heartless) has happened as a result. \n\nIt would be bad if an animal in a small food chain died out if animal A only ate animal B which only ate animal C etc.. but that usually isn't the case because of Food Webs. A food web is like a whole bunch of food chains put together. Let's say animal B goes extinct. Animal A wouldn't starve because it would eat other animals X,Y,Z. And Animal C would grow too wildly because animals J,K,L eat Animal C.\nFor a ELI5 example let's use a cat, a blue jay (or any other bird), and a worm. If the blue jay, went extinct, would all the cats go extinct and would worms take over? Not at all. Without the blue jay, the cats could go eat cardinals or more mice. And without the blue jays around, the cardinals (as well as other worm eaters) will have more worms to eat. The excess of worms will help the cardinal population grow but the cats will keep the population in check.\n\n**TL;DR** Not all animals are \"important\" because in most cases they are not the sole resource for another animal. ",
"Ecosystems are made up of countless relationships between different species, and they all work together to make sure everything functions. Our planet is like a ship, and all the species are like the nuts and bolts that keep the ship afloat. If you're on the boat, and you find out that one of the bolts came loose and sank, I imagine you would start to worry about how important that bolt was, what the underlying problem was that made the bolt come loose, and whether that problem is going to keep making the ship fall apart. If the right bolt comes off, the whole ship could easily fall apart and sink.\n\nJust like the earth, the ship would still be there if it sank, but you can be damn sure it wouldn't have people living on it.",
"Even if we don't know at the moment, it's better to be safe than sorry because the removal of tigers might have cascading effects that would be damn near impossible to predict. It could result in the collapse of an ecosystem through a domino effect (and no this is not a slippery slope argument; it's called interconnectedness and ecology). \n\nHowever tigers don't seem like they would have as much as an effect, as say the removal of bees from an ecosystem, because they are top predators. Although you can look at what happened when Wolves were extirpated from the United States....it had cascading effects that even effected the Aspen (tree) population. Here's a scientific study that shows what happens when a top predator (wolves) are removed from an ecosystem: \n\n_URL_0_\n\n-5th year Wildlife major from Humboldt",
"Another issue is that endangered species are easier to regulate than other aspects of our environment. It's easier to protect a river because there is an endangered species of fish living in it than because we're doing a lot that endangers the life of the river (taking water out, building dams, sometimes introducing pollutants, etc). I'm just gonna use the endangered fish example here because it's the one I know-- I live near the Rio Grande, and our local endangered species of interest is the silvery minnow.\n\nSo you have the Rio Grande, right, and this river has gone through a LOT of changes since humans started living in the region-- we use the water like crazy-- and that changes the health, and the overall ecosystem, of the river. There's not any big laws that it's easy to point to and say \"we're making the river work less well, let's fix that\", but there is the Endangered Species Act, and the silvery minnow is a protected species. So the silvery minnow ends up being less important for *itself* but instead is the canary in the coal mine for the entire river: if the minnow's dying off, we need to fix the river.\n\nI'm not sure if this is the case with all endangered species-- I'm pretty sure it's not-- but in species where the entire environment is threatened, it's definitely the case. \n\nThe polar bears are another example-- it's easy to point at the diminishing population of polar bears and drowning bears photos and say, oh shit, we're destroying the bears, and a lot harder to say, oh shit, we're destroying an entire ecosystem because the ice caps are melting. Unlike the minnows, the polar bears have great PR-- the term \"Charismatic Mammalian Megafauna\" was coined for species like bears, tigers, lions, etc: it means that these species are well-liked among humans, and so humans will work harder to protect them than less pretty creatures.",
"If I were to actually explain it to a five year old this is what I'd say...\n\nNature is kind of like a sports team. All the animals use teamwork, in a way, to continue the health of the whole system. When you kick one player off the team, none of the other players can rely on their skills anymore. If that happens, the whole team can fall apart. \n\nAdmittedly this is a vast oversimplification but it nonetheless holds true.",
"In addition to all the other answers, large predators are a kind of umbrella for other animals. Tigers require quite an amount of space and resources for their territory that they share with various smaller animals. When we protect the tiger, we also protect lots of other animals that share that space. So it's not just the tiger you protect, it's the whole system. You let the tiger die and we start losing other less noticeable animals that needed that land too.",
"There's a great interview about this with Colbert:\n\n_URL_0_",
"Like you're 5?\n\n**TIGERS ARE AWESOME!!!**\n\nSeriously, [what more proof do you need](_URL_0_)?"
]
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[
"http://www.reddit.com/r/explainlikeimfive/comments/ohjud/eli5_why_should_i_care_if_pandas_go_extinct/"
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[],
[],
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"http://www.reddit.com/r/explainlikeimfive/comments/psas1/eli5_why_it_matters_if_a_species_like_the_tiger/c3ru6s0"
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[],
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"http://en.wikipedia.org/wiki/Passenger_Pigeon"
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[],
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"http://www.bioone.org/doi/abs/10.1641/0006-3568(2004)054%5B0755:WATEOF%5D2.0.CO%3B2"
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[],
[],
[],
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"http://colbertnation.com/the-colbert-report-videos/171137/june-10-2008/alan-rabinowitz"
],
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"http://chutzpah.typepad.com/.a/6a00e55180ed5c883401310f3ea01c970c-pi"
]
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|
2v0c7z | why we don't use kilo-seconds, kilohours, gigaseconds ? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2v0c7z/eli5why_we_dont_use_kiloseconds_kilohours/ | {
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"Kilosecond and gigasecond are actually used in some scientific things. Kilohour wouldn't be used because an hour is 3600 seconds so you'd be better using \"megasecond\".\n\nThese would only really be used for very long, no very precise measurements of time",
"Can you think of a particularly good reason why we should? A primary use of our current system of time is mapping a relatively regular set of periods against the passage of a day. \n\nA day is 86.4 kiloseconds though, so if we based time on that sort of thing, well, the numerical value for a particular time of day would continuously change. \n\nA kilohour, well, that'd be 41.7 days. What use does that have? A gigasecond? That's 31.7 years. \n\nWhat's the value of these measurements, in our day to day operation, as compared to our current system which, while arbitrary, provides us a consistent basis? ",
"Because our system of time operates in a base 60 mathematical system, while the metric prefixes (kilo, giga, mega etc) operate in a base 10 mathematical system.\n\nUsing your kilo-seconds example, the kilo metric prefix denotes 10^3, thus a kilo-second would denote 10^3 seconds, or 1000 seconds. This is pretty useless for us, because it is not easily divided into higher or lower units of time. \n\n1000 seconds is ~16.6 minutes, same for a kilo-minute = ~16.6 hours. The different bases make the results more difficult for us to use."
]
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[],
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1jf101 | how is data in a database indexed and how does it speed up queries? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1jf101/eli5_how_is_data_in_a_database_indexed_and_how/ | {
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"They speed up queries because they make binary searching possible. I'll try to explain.\n\nImagine a database table with 10.000 records. If you would search this table for a certain record without indexing, the search will start at record 1, check that record if it matches your search criteria and go all the way down to the last record until the record is found. It'll take a long time.\n\nNow, you create an index on that table using let's say two fields. You know an index has to be unique per record right. This is because each index can only refer to one record. Why will become clear in a minute.\n\nWhat actualy happens is that a *second* table is created containing one field, namely a combined string of all your index fields. This table is also sorted.\n\nNow if you search that same table using the index, what actualy happens is that the *second* table is searched using a binary search. A binary search will not start from the top record. It will check the *middle* record with your search criteria. If it matches well ok then record found, if it doesn't match however it will check if the value is smaller then the value in the middle record. If it is smaller, it will do the exact same thing on the lower half of the table and continue until record is found. If it is greater it will use the top half. This way it doesn't have to search all records and that's why your query will go a lot faster.\n\n\nsource: I'm a software engineer",
"To add a more ELI5 answer to this.\n\nImagine the data is in a filing cabinet, without any organization it may as well just be all in 1 giant pile, with indexing you organize everything into the alphabetical folders, and further beyond that.",
"Here is another metaphor:\n\nImagine a database as an old school phone book. You know, the one made of dead trees. Imagine that you are looking for \"Paul\". On the side of the book are little black marks that tell you what letter is at the beginning of each section. So you can very quickly go to the 'P' section and start searching there. If you didn't have the black index mark that tells you where 'P' is then you would have to page through the whole phone book looking for all the P-names.\n\nNo extend this to a computer: The index says that all the 'P' names start at record 498035 and continue until 509243 so you only need to search in there to find P, or it doesn't exist."
]
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58uhyf | why was everything paid for in cents in the early 1900's and how did it come to change to dollars? | Litterally explain like im five, my daughter asked me this question today and I want to give her an answer she would understand? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/58uhyf/eli5_why_was_everything_paid_for_in_cents_in_the/ | {
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"The government creates more money over time and therefore there are too many dollars chasing too few things, meaning the whole economy will adapt to to needing more dollars for each thing. This means both wages and prices go up equally in the long run",
"Back in the day, dollars were like a certificate for gold you had in the bank and a dollar was relatively a lot of gold. Because of that, there was very little money on the market for all the services and products being offered, so things had to cost just fractions of dollars.\n\nAt some point, people realized that dollars didn't need to be associated with any amount of gold*, as long as people trusted in its value. That allowed the government to print lots of money. The government produced more money than the products and services increased. With this surplus of money in the market (relative to the amount of products and services), the prices increase in an effect called inflation.\n\nInflation occurs at some rate pretty much every year, meanwhile deflation (increase in offers bigger than increase in money available) occurs very rarely. And this constant growth in prices called inflation is what caused dollars of today value the same as cents of dollars from the past.\n\nEdit: spelling"
]
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[],
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2aobmv | what is the connection between birds, reptiles, and dinosaurs? | As the title says, does anyone have a ELI5 answer for their connection? Are reptiles and birds from dinosaurs or are birds a subset of reptiles?
Sorry for seeming uniformed. :( | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2aobmv/eli5_what_is_the_connection_between_birds/ | {
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"Dinosaurs are a diverse clade of reptiles. Birds are descendants of dinosaurs, and technically by the phylogenetic system (which classifies an organism based upon its ancestry) thus are dinosaurs and also reptiles.\n\nHowever, by that measure, humans are also reptiles (but not dinosaurs). As such, there are limits to the usefulness of applying such classifications too widely. ",
"Reptile is a poor term in relation to evolutionary theory. Reptile applies to any animal with a host of features that may or may not be closely related at all. This is especially notable with extinct animals like dimetrodon who are often called reptiles but are really closer to mammals.\n\nDinosaurs, because of their skin, are often called reptiles. But they had as much in common with modern snakes and komodo dragons as we humans do."
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1u383k | what is the strange tingly feeling i get when i consciously relax or 'reverse-flex' my legs? | Maybe I'm the only one this happens to, but I find that I can relax my legs in a strage way when lying down. It involves no motion, and almost feels like I'm flexing in reverse (rather than tightening, it feels like my muscles are loosening). I get a weird tingly/empty feeling in my legs, but can only hold the relaxation for a moment. I also only seem to be able to do this with my legs. Can anyone explain this? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1u383k/eli5_what_is_the_strange_tingly_feeling_i_get/ | {
"a_id": [
"cee23mr"
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"text": [
"I can also do this but have never been able to describe it and thought I was alone. I can seem to do it with my entire body."
]
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5zg9v3 | why are there no high quality videos of planets, or probes crashing into the planet? | If a signal is sent from the probe before it de-orbits to let's say jupiter, can we pick it up and see the full video before the impact point (or the point in which the whole probe burns)? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5zg9v3/eli5_why_are_there_no_high_quality_videos_of/ | {
"a_id": [
"dexvh2s"
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"score": [
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"text": [
"The bandwidth probes send data over is very limited. That's not a huge problem when you have days or weeks to take and transmit images, but it greatly limits your ability to steam live data."
]
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[]
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|
6znq78 | why do rovers such as the mars curiosity rover have wheels instead of tracks, like a tank? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6znq78/eli5_why_do_rovers_such_as_the_mars_curiosity/ | {
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"Because even if it was tracks it still need to have wheels to guide and drive those tracks. It adds unnecessary weight, which is a huge deal for anything going into space. It also adds unnecessary complexity, something else that might go wrong and screw up the whole mission, which is something you want to avoid at all costs.\n",
"Tracks may be more capable in rough terrain, but they're much more mechanically complex and prone to breaking down than wheels. You can't exactly send a mechanic to fix a broken track on Mars.\n \nBesides that, it would add a ton of weight and space which is a big problem in aerospace engineering - every pound spent on tracks is a pound that can't be used for better scientific instruments, solar panels, batteries, cameras, etc.",
"It's not so much wheels as the rocker-bogie suspension that's key. It allows it to stay level as it climbs terrain, and to keep all of it's wheels on the ground.\n\n_URL_0_"
]
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[],
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copg5t | what happens in your brain when your getting better at a certain skill? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/copg5t/eli5_what_happens_in_your_brain_when_your_getting/ | {
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"So when you do actions (and everything else) neurons fire in your brain. They connect to other neurons. If you're going to kick a ball you raise your foot and swing it forward to try to make it go where you want to. If you do this enough times, all these connections between neurons get stronger. Thousands and thousands and millions of times. You get better and faster. That is mastery. That Bruce Lee (?) Quote about like I don't fear the person who has practiced 10,000 different kicks but the one who has practiced one 10,000 times."
]
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||
1tnkfu | does mixing ingredients separately actually affect how the end product turns out? if so, how? | I was baking Christmas cookies and I realized that it always has you mix ingredients separately, and then blend them all together. Why is this? If you're just mixing them all together in the end anyway then what difference does it make? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1tnkfu/eli5_does_mixing_ingredients_separately_actually/ | {
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"Say you have vinegar, baking soda and water. If you mix the baking soda and vinegar it will quickly expand and if you add water it will just be foam on top of water. If you mix the baking soda with water then add the vinegar, the chemical reaction will be subtle sy best and it will just be a liquid mix on top of powder.",
"There are certain things that you can over-mix. If you blend the sugar and butter together first, you can ensure that the sugar fully incorporates into the butter without over mixing the flour. \n\nHere is a link explaining over-mixing much better:\n\n_URL_0_\n\n",
"It's because the order and method you mix things can have a huge effect on the outcome. For example, let's take the most common mixing method, the creaming method: \n\nFirst you cream together the butter and sugar, because the sugar punches microscopic holes in the butter that aid in leavening. Any additional ingredients at this stage would inhibit that. Then you slowly add the eggs, just a few at a time, because eggs have a lot of structure and take time to get fully incorporated. You sift all of your dry ingredients together because powders like to clump up, and once those clumps get wet they're much harder to break up. You add your dry batch last to minimize gluten development, because any mixing after the flour is added will create gluten and could make your product tough. If you have additional wet ingredients, you alternate adding portions of your wet batch with portions of your dry batch to allow the flour time to soak up the added moisture.\n\nIf you were to take all the ingredients of a butter cake and just toss them in a mixer, you would end up with a lumpy brick. If you follow that method, you'll get a tender, airy cake with a consistent crumb."
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1on9hn | how can liquid coffee creamer be left at room temperature without going bad? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1on9hn/how_can_liquid_coffee_creamer_be_left_at_room/ | {
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"Doesn't the creamer have to go in the fridge after opening it? The sealed creamer shots stuff lets in no oxygen and no chance to breed bacteria, but ......idk",
"One word. Salt. \nI used to work at a Tim Hortons, the creamer is like a milky salt cocktail. I've seen year old bags of creamer get used. Worst part is it appeared to be fine. \nI personally protest creamer, shit fucks my stomach up.",
"Depends on the creamer. In some cases it's got zero nutritional value which makes it rather unlikely that anything can grow in it. Bacteria need energy just like you and I do and being deprived of both sunlight and food will kill just about everything.\n\nCreamer that is actually dairy based can be left at room temperature too through a process called ultra pasteurization. Pasteurization is just a heat-treating of a product to kill off bacteria and stuff that's been ultra pasteurized is more or less sterile. Without any bacteria to grow there's no need to keep them cold to slow their growth.\n\nWe don't ultra pasteurize everything though because its a more expensive process and some folks think it changes the taste of the product. ",
"I've seen what OP is talking about. A restaurant about a half-mile from my house has individual coffee creamers at the table in a little basket. And yes, on the packaging it says it's real half and half, and it also says no refrigeration required.\n\nI did a little googling and found [this.](_URL_0_) The answer to your question is because it's ultra-pasteurized, and also because it's hermetically sealed (no oxygen can get in). There is also Sodium citrate which keeps the fat from separating from the other ingredients."
]
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[],
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"http://blogs.howstuffworks.com/2010/09/17/good-question-why-dont-little-half-and-half-creamers-for-coffee-need-refrigeration/"
]
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||
2gzelj | why does spain claim english control gibraltar is illegal when spain itself has the enclaves of ceuta and melilla in north africa? | Spain signed a treaty ceding Gibraltar to Britain over 300 years ago, but claims that it is part of Spain and should be returned. But Spain itself has two enclaves in Africa, Ceuta and Melilla, which Morocco has demanded be ceded. How does Spain distinguish between these two cases. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2gzelj/eli5why_does_spain_claim_english_control/ | {
"a_id": [
"cknw2c0"
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"text": [
"Not an answer to your question but I believe you mean 'exclaves'."
]
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[]
] |
|
7xhff8 | how can scientist determine things like top speeds of dinosaurs if all they have to go off of is bones? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7xhff8/eli5_how_can_scientist_determine_things_like_top/ | {
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"The bones are pretty informative really.\n\n\nWhen put together into a skeleton the same way you can roughly imagine the way the original dinosaur looked scientists have developed methods to very accurately figure out how the thing looked as well. Muscles are attached directly to bones (hence the name 'skeletal muscles'). The way they are attached to the bone allows scientists to understand how big the muscle is, what it is shaped like and where it's positioned. \n\n\nYou would also need the size, approximate weight and air resistance of the dinosaur which is all very conveniently presented by the skeleton. By measuring the skeleton you can easily get all this.\n\n\nWith that information along with a lot of trial and error they can slowly understand what is the most comfortable way for the dinosaur to run. This is done in the same way an physiotherapist discerns something about their patients. (I don't really know how its done. I'm not a physiotherapist. Maybe they bring a physiotherapist with them while figuring this out.) \n\n\nThe last thing they need something that you can also tell from just the bones. Or more specifically the DNA. The DNA basically tells the body how it should grow and function. From the DNA scientists can decode 2 different things: 1. how enduring the muscles are and 2. How fast the muscles are. Every muscle is a certain amount enduring and certain amount fast because of what kind of DNA the animal has inherited. Its the same for humans, mammals and pretty much all animals so it's only slightly harder to figure out the same for dinosaurs. \n\nWith all this information; muscle size, muscle position, muscle speed, muscle endurance, optimal sprint patterns, and size, using simulation programs or very complicated math/physics you can calculate the max speed.\n\n\nThe physics is very complicated but I know it's possible. The simulations are really cool. I've seen some myself. The simulations in Jurassic park are pretty accurate as well or so I've heard.",
"Most of the speed information comes from footprints. There are a lot of dinosaur track fossils preserved in muds and fine-grained sandstones. Measure the depth and angles of the tracks, the distance between the tracks, and use analogous information from modern animals to identify relative speeds and weights.\n\n[Here's a reference on how it's done](_URL_0_) and [a course worksheet to calculate it for yourself](_URL_1_), and [another one](_URL_2_).\n\nYou don't need DNA for this, or even bones--just the tracks. It does help to be able to identify the species of dinosaur--that gives you a starting place for size and weight.\n\nSource: geologist"
]
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[],
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"http://www.ucmp.berkeley.edu/diapsids/buzz/locomotion.html",
"http://faculty.msj.edu/kritskg/tracklab.pdf",
"https://www.amnh.org/content/download/49379/751532/file/dinoactivity_speed.pdf"
]
] |
||
3h02w3 | why are there so many firefighter death with the explosion in tianjin,china | I recall the feed saying 120 rescue personnel died. My understanding is that the blasts were close together and that firefighters and police where dying as they were trying to get it under control. Given modern firefighting techniques why are so many dying? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3h02w3/eli5why_are_there_so_many_firefighter_death_with/ | {
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"The second explosion was huge. First responders went to the scene of the first explosion and were caught by the second one.",
"I heard there was a fire 3 hours before the first explosion. Many firefighter tried to kill the flames before everything went worse. There was a chemical fire. And a lot of cars and tanks filled with high explosive stuff like gas. And if it starts to burn and one thing is gonna start to explode there will be a chain reaction. If you take a closer look to the posted images there are a lot of cars, container and a huge flat area. It's not easy to hide. Especially if it starts to explode. It's a thing of seconds. The best equiment in the world can't save you against a huge explosion. And because you can't see a explosion befor it happens there was no chance to hide. "
]
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[],
[]
] |
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1lrbq5 | weather maps and how to read them. | I cannot seem grasp this! I'm more interested in Wave Forecast maps, not sure if these are different. Any explanations welcome. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1lrbq5/eli5_weather_maps_and_how_to_read_them/ | {
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"text": [
"If you're talking about regular maps. [This looks like a nice key to everything.](_URL_1_) Wave maps [like this](_URL_0_) show how tall the waves are and in what direction they're going in."
]
} | [] | [] | [
[
"http://www.bom.gov.au/australia/charts/viewer/index.shtml?type=windWave&tz=AEDT&area=Au&model=CG&chartSubmit=Refresh+View",
"http://i.imgur.com/6GFDP1i.jpg?1"
]
] |
|
1ukfln | why do credit cards have those extra 3 numbers on the back? | I figured it would have something to do with online card number theft (since if someone steals the card they have access to both the 16-digit number and the additional numbers). How do they, and why do they, provide additional security? Just curious. Thanks! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ukfln/eli5why_do_credit_cards_have_those_extra_3/ | {
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"It's called the CSC and stands for Card Security Code. It's simply an extra verification to up the security.\n\nYes, your credit card is usable when stolen. \n\nAlthough in Europe we also use pincodes as an added security measure. Not sure what the situation in the US is at the moment.",
"The CV number is used in online purchases to prevent fraud. The user needs to have access to both sides of the card to use it and not just a photograph of one side which once was a common way to steel CC info.",
"One of the main security benefits not mentioned so far is that retailers (in particular for \"cardholder not present\" transactions like internet/over the phone sales) are not allowed to store the CV2 code after the transaction has been completed.\n\nThis means that if their database of card details is compromised, the details are a lot less useful.\n\n(Also, the CV2 is not included on the magnetic stripe which makes it more difficult for unscrupulous retailers to quickly swipe the card through a 2nd machine and use the details later - they would have to note down the CV2 code as well.)"
]
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1ne7qw | what would hallucinogens be like for blind people? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ne7qw/eli5_what_would_hallucinogens_be_like_for_blind/ | {
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"I have nothing to back this up but, since this is the internet, here we go...\n\n\nThere would still be auditory hallucinations of course, and probably what would be the equivalent of closed-eye hallucinations in us sighted folks. So kinda vague shapes and lights just behind the darkness (or whatever) they see (or whatever). Not to mention the hysteria that can come along with various mushrooms or LSD. Confusion and laughter and all that would still occur.\n\n\nIf anyone can confirm or counter anything I said that'd be awesome, as I said those were just educated guesses.",
"Excellent question, thank you for asking it... ",
"Not really a five-year old answer, but here's an [old study](_URL_0_) that talks about just that.\n\nIf you have memory of what visual things are then you will experience visual hallucinations, otherwise there isn't any visual. Since hallucinations can be totally auditory then I would expect that they play a major role. Also, synesthesia would probably have a more significant effect ",
"I don't know but I grow shrooms and I have a blind neighbor done the hall... I call him Ray charles bc he also plays the piano or keyboard a lot.",
"I'm blind in one eye so I can provide some insight but I'd imagine things would be different for a person who is completely blind and has been for life. When my blind eye is open and I look through that with my seeing eye closed, it's a bit of a clusterfuck. The patterns are kind of everywhere, for lack of a better term, as in when I see things through my good eye the patterns are more structured and layered on top of things. With my bad eye they're much more disorganized and scattered all over my vision. Most people that are considered blind actually have some eye sight, I fall into that category as well with my one fucked up eye. A lot of what I normally see through it is those light rays, like if you squint your eye looking at a street light at night. So when I'm on mushrooms or acid the waves that I would normally see on the ground are moving around the light rays. It's kind of hard to describe. If you want me to define things a little better just ask me a question and I'll do what I can to answer it.\n\nAlso, from what I've heard, people who've been completely blind from birth have an almost entirely different experience from what we have. They've never seen colours before and have no reference to go back to either if they do see them with their hallucinations. Their closed eye visuals are another experience as well because, as it was put to me before, someone who's blind doesn't see darkness, black or white, they see nothing. I can't really describe what I haven't experienced though so I'll leave more details for someone else to try and describe.",
"[A blind man did an AMA on this a while back](_URL_0_)\n\n\"I have tried many diferent types of halucinigens. I can tell you first hand, that visuals are possible even for the totally blind. Well, I can se light and darkness, and if something blocks the light, I can se a blurry shape, but nothing that I can make out clearly. Under the influence of various antheogins, I have experienced sights such as various lights, which would change shapes and then melt in front of me. Once durring an experience with Salvia extract, I nearly became my rockingchair! I don't mean that I \"melted in to it\", I mean that if I hadn't jumpped out of it, I'd have turned in to the actual chair. I know that sounds crazy, but that's what happened. Naturally, sounds are a big part of my trip experiences, but I have seen somethings as well. I had a buddy that had his own light show setup, and we used to trip out on really good acid, (this was back in the early 80's when they still made it), and he'd shine these high powered lights through prisoms, and I saw all kinds of wild stuff. I believe I have seen color because of these experiences.\"",
"Blind people? What makes YOU think you can SEE?",
"And can schizophrenic deaf people hear voices??? Can they be schizophrenic??",
"I'm a blind guy who's done mushrooms. I've been 100% blind since birth. I didn't see anything. I hallucinated sounds and feelings, like the whole house seemed to come alive. The walls felt like flesh I could hear it breathing, etc. I think I had some other hallucinations I don't really remember now like people's voices were altered somehow.",
"One thing to understand is that visuals are only a small part of a hallucinogenic experience. The way your mind warps reality is the heart of the experience, and even if you're completely blind, that will find a way to manifest itself. If your visual cortex doesn't work in any way, the drugs will still affect what you *can* perceive. Auditory hallucinations will be very prominent because sound becomes a primary sense for the blind. ",
"It'll depend on when they became blind. If you got your eyes gouged out right now, you'd still be able to hallucinate, because your brain already understands the concept of vision.\n\nIf you were blind from birth, that's a different story. The connections between your optic nerve and your optic tectum and occipital lobe in your brain aren't fully complete right at birth. The two form complete connections further along during infancy with repeated visual stimulation. This is why cataracts are so dangerous for newborns. They need to be taken care of immediately, or else you won't get the visual stimulation required to stimulate connections between your eyes and your brain. You could also theoretically blindfold a newborn for a couple months and get the same result.\n\nThey also found that your brain sees things \"in lines.\" If you only blind-folded a baby with parallel horizontal slits, it would grow up not able to see horizontal lines. If you did parallel vertical lines instead, the baby wouldn't be able to process vertical lines. Same thing goes for any angle, whether 30 degrees, 45 degrees, etc.\n\nSo if you were blind from birth, your brain doesn't understand the concept of sight. Think of it like trying to see behind you. You can't. There isn't a visual field behind you... now imagine if that lack of a visual field applied to everything in front of you too. That's what it's like to be blind from birth. You wouldn't be able to hallucinate, because there's no field of vision to hallucinate from.\n\nFYI: Bane should be blind from birth... if he was born in darkness and wasn't exposed to light until he was a man, he wouldn't have had the proper visual stimulation to make proper connections between his eyes and brain.",
"I'd say psychedelics are about 75% mental and 25% visual. While some blind people have been know to see some visuals while tripping, I'd imagine the mental aspect and and other senses are going bonkers. ",
"They'd taste colours.",
"_URL_0_\n\nIf a damaged visual cortex weren't the cause of their blindness, some hallucinogens could possibly allow them to see sounds, tastes, smells, or touch :)",
"If a person is blind from anything other than brain damage the visual cortex is still perfectly able perceive light and color.",
"Scary as fuck.",
"My phones almost dead but hallucinogens activate your pineal gland in your brain, which is known as the third eye, you see closed eye visuals, its kaleidoscopic and bright in your brain as you trip. Similar to a dream ",
"Reading through these comments, I kept thinking, \"I wanna hear from a blind guy. Where are all the blind redditors' comments?\"\n\nMaybe I *am* actually 5.\n\n"
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4c9zyg | how are newer lights produced to generate more light and less heat? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4c9zyg/eli5_how_are_newer_lights_produced_to_generate/ | {
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"The basic mechanism behind incandescent bulbs is \"get the filament hot enough to glow white\". Getting hot is necessary for them to function.\n\nModern bulbs are typically fluorescent or LEDs which function by a different mechanism. This means getting hot isn't necessary (and is generally undesirable), so it's possible to engineer them to be more efficient and produce less heat.",
"First you need to understand what light and heat radiation is. They are both part of the electromagnetic spectrum. Visible light is the part of the spectrum we can see, infrared radiation is just outside of what we can see and is heat.\n\nFor example, if we could see infrared your body would be glowing, as you are radiating heat. But if you heat something up enough, it also starts glowing in the visible spectrum. Like heating up iron enough it start to glow red (as red it closest to infrared), and heating it up even more it glows orange (even further in to the visible) and then it glows white (all of the visible spectrum).\n\nThis is pretty much how an old fashion light bulb works, it sends electricity though a small piece metal, heating it up to glowing white. But most of the energy will not be visible light, it will be infrared light, which is kind of useless as we can't see it.\n\nModern light bulbs, especially LED, are much better at only producing visible light. So rather than wasting energy producing infrared heat radiation, it only makes light in the visible spectrum. Which obviously uses much less energy."
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6g93k6 | the usa military ranking system. | I just finished watching band of brothers and I'm curious what ranks there are and how long it would take to reach them. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6g93k6/eli5_the_usa_military_ranking_system/ | {
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"in the US (i'm in Canada) it's pretty much a linear curve, but I think this article does a much better job ELI5 than I could _URL_0_",
"There is a huge difference between rank progression in wartime, vs promotions in peacetime.\n\nFor instance, a \"bird colonel\" in the Army during peacetime, might have 25 to 30 years service and probably be in his 50's. \n\nDuring WW2 there were \"bird colonels\" who were in their late 20's and had less than 6-8 years of service. \n\nThe war caused a tremendous expansion in the military, in 1939 the army had 139k soldiers, in 1945, 8.2 million. That's 43 times larger in war than in peace. \n\nSo there was no way to really let officers advance through normal channels, you really had to just promote and hope for the best.\n\nEnlisted ranks were similar. ",
"It's important to start out with the point that there are 3 separate categories of military rank:\n\nEnlisted (E1 thru E9)\n\nWarrant (CWO1 thru CWO5)\n\nCommissioned (O1 thru O10)\n\nEnlisted is the \"grunt\" category of the people sent to directly do things.\n\nEnlisted can be broken into 9 pay grades. These pay grades categorized into into 3 sub-Categories. \n\nSimple seamen, soldiers, and marines are pay grades E1 thru E3.\n\nStarting at E4, the ranks become Non-commisioned officers (with some oddness with the army making some E4s \"specialists\", which get the pay w/o the non-com status). These are Corporals and Sergents in the Army/Marines, and Petty Officers in the Navy. These ranks are given limited authority over a few soliders/marines/sailors in order to assist and organize them in carrying out their orders. In the context of Band of Brothers, these ranks would be in charge of leading a fireteam (3-4 soldiers) or squad (two fireteams).\n\nStarting at E7, these ranks are considered \"Senior Non-commisioned Officers\". They are going to be incharge of coordinating and training the non-coms under their authority and advising the officers. These are Sergents First Class, First/Master Sergents, and Sergent Majors in the army, and Chief Petty Officers (including Senior Chief and Master Cheif) in the Navy.\n\nI'm going to skip CWOs because i really never had much exposure to them, and they are a special case that doesn't usually fit into the typical command structure.\n\nCommissioned officers are a bit complicated because there are to types that are independent of rank: Line and Staff. Line officers are the command officers, so i'll focus on them. Commisioned officers are the administrative and tactical leaders of their units, and junior officers (ensigns [navy only] and leutenants) generally have authority over a Platoon (2 or more squads), along with a senior NCO as an advisor. Higher ranking Officers typically have authority over larger units. The ranking nomenclature between the services is pottentially confusing at this point (Army Captain = O3, Navy Captian = ~~O5~~ O6 **OR** commanding officer of a ship), so I suggest simply looking up the officer's pay-grades for that.\n\nEdit: Also, an additional, important point is the distinction between Rank and Authority. Authority trumps Rank, which means a junior enlisted that is given authority to control access to a location can safely block an O10 that is not authorized to access that location, with force if necessary. ",
"for the enlisted ranks part of your question was how long does it take to advance in rank.\nE1-e3 = right out of boot camp a guy will usually be e1or e2\nThey advance 1 pay grade usually every 9-12 month until e3.\n\nAfter e3 - for each subsequent advancement they compete with their peers.....through a combination of a board or a written test and review of the points achieved from awards and periodic evaluations.\nE4 = 2-4 years in military\nE5 = 3-9 years in the military\nE6 = 7-16 years in the military\nE7 = 8-19 years in the military\nE8 = 15-23 years in the military\nE9 = 18-25 years in the military\n\nThese are all rough estimates because it really depends on the persons performance and how their peer group is manned. So for example if the guy comes in as a medic and we have lots of medics - it may take him a while to get advanced because he is competing with alot of guys for the same spots.\nOn the other hand if he comes in and goes to nuclear power school - he is highly likely to get advanced first or second time he is eligible for every advancement because nuclear techs are in high demand and the military rewards them with quick advancement to try to keep them in the military instead of taking those skills to the civilian world where they can make more money.\n\nFor officers its much harder to describe a time period....but they get near automatic advancement from O1 to O2 and then to O3.....and after that they compete with their peers for advancement each year. They must be selected for advancement within a certain time period or they will be released and not allowed to stay in the military anymore. ",
"So Band of Brothers was set in WW2, where the ranks for the military were a bit different than today (where they have been standardized).\n\nPromotions back then, due to the massive expansion of the military, happened a lot quicker: it was possible for people to reach Colonel (O-6) in their late 20's, simply because there was space in front of them/they needed one/the guy in front of him got killed.\n\nAn example in Band of Brothers is Major Winters: he went from 2nd Lieutenant in 1942 after commissioning from OCS, was a 1st Lieutenant on D-Day, got promoted to Captain on July 1st, 1944, then was a Major.\n\nIn today's military, you have two years as a 2nd Lieutenant, followed by 2 years as a 1st Lieutenant, followed by 4-6 years as a Captain. Those ranks are mostly automatic - starting with Major, however, you face a promotion board, and if you are passed over for promotion twice from here on out, you essentially are out (you can't be promoted essentially - if you make O-4 though, you are eligible for retirement and can stay in to hit 20 years).\n\nAs far as the ranks go:\n\n**Enlisted**\n\nPay Grade | Army | Marine Corps | Air Force | Navy/Coast Guard\n-- | -- | -- | -- | --\nE-1 | Private | Private | Recruit | Seaman Recruit\nE-2 | Private | Private First Class | Airman | Seaman Apprentice\nE-3 | Private First Class | Lance Corporal | Airman First Class | Seaman\nE-4 | Corporal/Specialist | Corporal | Senior Airman | Petty Officer, 3rd Class\nE-5 | Sergeant | Sergeant | Staff Sergeant | Petty Officer, 2nd Class\nE-6| Staff Sergeant | Staff Sergeant | Technical Sergeant | Petty Officer, 1st Class\nE-7 | Sergeant First Class | Gunnery Sergeant | Master Sergeant | Chief Petty Officer\nE-8 | First Sergeant / Master Sergeant | First Sergeant / Master Sergeant | Senior Master Sergeant | Senior Chief Petty Officer\nE-9 | Sergeant Major | Sergeant Major / Master Gunnery Sergeant | Chief Master Sergeant | Master Chief Petty Officer\n\nAs you can see, the Navy/Coast Guard are identical, the Army/Marines are pretty similar, and the Air Force... who knows why the Air Force feels the need to be different but you do you I guess\n\n**Warrant Officers**\n\nPay Grade | Rank\n-- | --\nW-1 | Warrant Officer (Army/Marines only)\nW-2 | Chief Warrant Officer 2\nW-3 | Chief Warrant Officer 3\nW-4 | Chief Warrant Officer 4\nW-5 | Chief Warrant Officer 5\n\nNote that the Air Force has NO warrant officers, while the Navy/Coast Guard do not have a W-1 rank.\n\n**Officers**\n\nOfficers are easy:\n\nPay Grade | Army/Marines/Air Force | Navy/Coast Guard\n-- | -- | --\nO-1 | Second Lieutenant | Ensign\nO-2 | First Lieutenant | Lieutenant Junior Grade\nO-3 | Captain | Lieutenant\nO-4 | Major | Lieutenant Commander\nO-5 | Lieutenant Colonel | Commander\nO-6 | Colonel | Captain\nO-7 | Brigadier General | Rear Admiral (Lower Half)\nO-8 | Major General | Rear Admiral (Upper Half)\nO-9 | Lieutenant General | Vice Admiral\nO-10 | General | Admiral\n\nThere is an O-11 rank (5-star), for General of the Army or General of the Air Force or Fleet Admiral, but those have only ever been issued for wartime commanders during WW2, and are not in use at this time\n\nedit: fixed formatting"
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bmobed | what is the purpose of fainting? what are the benefits of this mechanism? in extreme situations (e.g. being under attack) humans and animals sometimes faint but i see this as counterproductive and it would probability be better to become more alert in these situations, right? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bmobed/eli5_what_is_the_purpose_of_fainting_what_are_the/ | {
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"Our brains need a *lot* of blood to stay alive. Normally, our bodies work just fine pumping blood against gravity and up to our noggins, but sometimes things go wrong. If for any reason there's a drop in blood pressure or heart rate or reduced level of oxygen to your brain, your brain is going to make you faint. Why? Because it will make you horizontal very quickly, and that will help restore blood flow to your brain since your body is no longer working against gravity. So fainting (technically called syncope) is about preserving bloodflow to the brain, which will prevent brain damage. Preserving your brain is the paramount consideration. If your brain thinks it's not getting enough oxygen, it doesn't care about anything else in that moment. Anything that causes a sudden drop in blood pressure, or heart rate, or blood oxygenation can trigger fainting. Some of these things are physical, and some are psychological.",
"When I was younger, I would always faint when I got hurt. I came to realize that I would either hold my breath or hyperventilate when I was hurting, making myself pass out. So fainting wasn't the response to the situation itself, but to me not handling the situation well."
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5z1lzg | if wifi is an electromagnetic wave travelling at the speed of light, and it's digital, why does it slow down at distances from the router? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5z1lzg/eli5_if_wifi_is_an_electromagnetic_wave/ | {
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"It doesn't. The radio waves are getting to you at the same speed they always are. However, they might not *all* be reaching you because there are obstacles in the way. Furthermore, the *protocol* that is transmitted over those radio waves is limited by many factors, including computation speed of the devices dealing with it. "
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57cl5r | how is the environment affected if we draw enough energy from the sun through solar power for the entire planet? | I assume, the law of conservation of energy dictates that this energy is being taken from somewhere, therefore does this mean we would be effectively cooling the planet by not allowing energy to reflect back into the atmosphere? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/57cl5r/eli5_how_is_the_environment_affected_if_we_draw/ | {
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"Energy used by humans is so much smaller than the total energy hitting the Earth that it's completely negligible",
"Assuming that panels are 100% efficient, yes! But that isn't the case, panels does reflect light and get hot from the sun rays",
"Probably positive. The amount of energy absorbed and converted for human use will be only a tiny fraction of the total power that the earth receives.\n\nThe biggest impact is in far lower CO2, NO, O3, and micro dust emissions, thus limitting the greenhouse effect and the smog that occurs on too many places (e.g. LA & Beijing). The global warming will continue for a while because of the momentum builded up, but much shorter than if we continue as with fossile fuel and much safer than nuclear.",
"So we draw some small percentage of the light hitting a solar panel and turn it into electricity. \n\nThat electricity is then converted back into light, heat, or sound when it's used by appliances, electronics, A/C systems, etc...\n\nThe net effect is essentially zero because it all winds up as energy in the atmosphere when we use it.",
"You'd need to literally cover the Earth with perfectly efficient solar panels, as opposed to a tiny fraction of the Earth's surface (the vast majority of which is ocean remember...).",
"All the energy that gets absorbed by the solar panels and turned into electricity eventually becomes heat (much of it within a second or two), so it wouldn't meaningfully change the heating effect of the sun.",
"Actually no, because all the energy that gets turned into electricity eventually is converted back into heat as we run our lights and machines. Energy is conserved: what goes into human society must eventually come back out.\n\nThe net effect is probably a slight warming, because solar panels are darker in color than most land surfaces. So adding panels darkens the Earth: they'll absorb sunlight that otherwise would have been reflected away from the planet.\n\nHowever, this effect would be unmeasurably small, and far *far* less than the greenhouse effect caused by fossil fuels."
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6px3og | if windows 10 is the final version of the os with updates being free, doesn't that mean microsoft would lose a lot of money? | There will be people who haven't bought a PC yet and need to get a new computer and OS - fair enough. But how about millions like me who already have Windows 10? We likely won't be upgrading for a long time. Isn't Microsoft just losing a lot of money here? But they're a massive company and are much smarter than that so is there some way they're still able to make money with this free upgrade scheme? (aside from things like Xbox of course that isn't related to Windows)
Edit: Thanks for all the answers! :) | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6px3og/eli5_if_windows_10_is_the_final_version_of_the_os/ | {
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"People will always buy new PCs, and hence new Windows licenses. Sure they lose out on money from people upgrading their existing PCs to new versions of Windows, but in the grand scheme of things, how many people do that? Looking back, PC hardware has gone out of date much faster than versions of Windows.\n\nAlso Microsoft make money from providing services. Services that they can push via Windows 10. As well as other advertising pushed out to users. There's also the Windows store where they get a cut of all sales.",
"Most PC's are throwaway technology. When you get a new one, you have purchased another Windows license.\n\nYes, you can transfer licenses, and you'd do that if you are building your own PC to replace an old one, but that's the minority.\n\nAnyone who is buying a built PC (or if you get a new motherboard... Windows requires a re-buy on a new motherboard) is going to get a new copy of windows that MS gets paid for.",
"Microsoft (unofficially) welcomes you to pirate their OS if it would mean that you're running Windows instead of other Open Sources or Mac. \n\nWith the majority of users being tied to Windows, they have a monopoly over the PC market and therefore generate income from businesses, schools and other establishments by selling licence and subscriptions to programs such as Office, Excel and the likes. \n\n\n\n",
"They make more money on usage and data mining - the OS mandates the use of Bing and Edge and Cortana, all which track your habits which Microsoft uses to sell to advertises. The OS also serves ads directly. It is more beneficial for them to give it out for free so that more people are using it.",
"Adding on to what everyone else said, Microsoft is moving to a software as a service model. The most profitable games in the App Store are \"free\" to play, but come with microtransactions. \n\nThe latest version of Windows is littered with ads and software that used to be free, such as Solitaire, now costs a monthly fee.",
"You assume just \"buying\" the OS is the way to make money. Look at the Windows Store and other things involved. The real money in software now is subscriptions and \"__ as a service\". More and more software now can't be outright bought for X amount of money. A lot of software is now highly tied to cloud services too. Installing the OS (buying the initial part/piece/service) is just the foot in the door. ",
"Profits from desktop sales aren't really a priority for MS, the real cash comes from long term corporate and government contracts - software, custom updates, tech support, etc, etc. "
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66xw8t | how do people with metal body parts go through metal detectors at airports? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/66xw8t/eli5_how_do_people_with_metal_body_parts_go/ | {
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"They don't. \n\nThese days they are directed through the millimeter wave detectors. Or they can opt for a hand screening. ",
"My father has 2 fake knees. He carries a note saying that. He also gets screened and gets a pat down.",
"Depends on the material, how thick it is, how deep it's in your body. I have a stainless steel rod in my ankle about 8 inches long, and that's never set off any metal detectors in airports or anything.\n\nHowever, my dad has a titanium hip replacement that sets off pretty much every metal detector ever. \n\nWe both have a little card in our wallets that have the type of implant, where it is, and the doctors contact information if anything should pop up. ",
"A Turkish-American friend of mine looks very Middle-Eastern, speaks with a heavy accent, and has a metal pin in her leg. She goes through airport security *very* slowly, with pat-downs, handheld detector wands, and lots of questions. She has learned to show up early to allow time for the extra scrutiny she always draws."
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71g914 | why is jewelry and antiques placed on velvet and not other fabrics? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/71g914/eli5_why_is_jewelry_and_antiques_placed_on_velvet/ | {
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"Velvet photographs better when trying to capture something that sparkles. Most other fabrics will seem faded when you use a flash. Velvet stays as black as you see it with the naked eye. On or off film it makes things pop more.\n\nVelvet is actually really bad to have around antiques that can scratch."
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6kx54n | if a magnet is 'hovering' by being repelled by another magnet, is it's weight placed on the bottom magnet? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6kx54n/eli5_if_a_magnet_is_hovering_by_being_repelled_by/ | {
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"Yup. They will follow Newton's Third Law, for equal and opposite forces.\n\nAlthough I'd be careful about saying \"weight placed\"- the force applied is via the magnetic force interacting between the two, it just happens to be equal to the weight in this particular set up.",
"Think about a truck full of these magnets as you described. If that truck drove through a weigh station the weight of the magnets would certainly add up on the scale. ",
"Consider the atomic level: nothing is actually \"touching\" there either. Particles get close but are not in actual contact due to repulsive forces, similar to the magnet situation.\n\nIn both situations, the \"weight\" force is considered the sum of weights of all components.",
"Gravity is pulling both magnets down towards the center of the earth. The electromagnetic force is then pushing as well - each magnet pushes on the other. The force is strong enough at close distances (as they follow the inverse square law) to push stronger than gravity. But just as the bottom magnet pushes up, the top, hovering magnet is pushing down with the magnetic force. \n\nSo the bottom magnet has both gravity pulling it into the ground and the magnetic force pushing it into the ground. ",
"Yes and no:\n\nYes, there would be more force pushing the bottom magnet down.\n\nNo, the extra force is not called weight. Weight is a special name for the force caused by gravity on an object.",
"The question has already been answered but I'd like to try a simpler explanation\n\nLet's list down the forces involved \n\nThe **top magnet** is affected by gravity so it has a force going **down**. But it's also affected by the magnetic force of the bottom magnet so that's a force going **up**. Together they cancel each other out so the top magnet floats.\n\nThe **bottom magnet** is affected by gravity so it has a force going **down**. *And* it's also affected by the magnetic force from the top magnet, so that's another force going **down**. Together it totals the weight of both magnets!\n\n\nI tried my best to explain it without difficult words or needing prerequisite knowledge but I couldn't find a simpler word for force. Any suggestions are welcome",
"When in doubt, draw a free body diagram. In case you are unfamiliar, this where you draw arrows for all the known forces on \"body\" or object. We do this because of Newton's Law, and use it to help us better understand motions or stress on objects. We also take advantage of the fact that F(orce)=M(ass) x A(cceleration)\n\nOn the hovering magnet, it is motionless, so we know A = 0. Same for the magnet resting on the surface. On both magnets, we have multiple forces acting, but they all must cancel out, because no objects are accelerating. Since the directions exactly oppose each other the forces exactly cancel out, and there is no acceleration. \n\nFor the hovering magnet, we know the force of gravity is equal to the mass of the magnet times the acceleration of gravity. Since it is stationary, the magnetic force is exactly canceling out the force due to gravity.\n\nFor the magnet resting on a surface, we know the force of gravity is also the mass of the second magnet times the acceleration of gravity. We also know, since every action has an equal and opposite reaction (think of it as the hovering magnet pushing back on the resting magnet), that this magnetic force is equal to the gravitational force in the hovering magnet. But, since the stationary magnet is also not moving, we know there is a force opposite in direction that exactly matches the sum of the gravitational force and the magnet force on the resting magnet. The \"normal force\" of the surface pushing back against the magnet is equal to the sum of the force of gravity on the resting magnet, plus the force of gravity on the hovering magnet. Normal force is the \"effective weight\", as that is what you would see read out on a scale. But, normal force is not the weight. \n\nThought experiment: imagine both magnets lose their magnetism, and now are just resting on top of each other. What are the forces acting on each body now? What is different and the same between this scenario and the scenario you bring up?\n\nEdit: So to explicitly answer your question, the resting magnet does not \"gain weight\" by repelling a hovering magnet. If you put it on a scale, this would appear to be the case, but in fact, but that is because scales actually measure the normal force they exert, not the weight of the object on them. The term \"weight\" is reserved for the force of gravity on an object due to *its own mass*. Consider when you measure yourself on a scale, and a friend pushes down on your shoulders. Do you weigh more because a friend is pushing you harder into the scale? Do you weigh less if your friend is slightly lifting you upwards? The answer is no, the scale is simply reading out the normal force it is exerting, which is simply your weight plus any outside forces it must counteract to stop your acceleration.\n\nEdit 2: Link to diagram\n\n_URL_0_"
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5lwfev | why do all old movie trailers have narration in them? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5lwfev/eli5_why_do_all_old_movie_trailers_have_narration/ | {
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"Because people generally want to know what a movie is about before they go see it and in the ~2 minutes a trailer lasts voiceover narration is the best way to communicate to the viewers what the movie is about."
]
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[]
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||
70dip2 | why is the internet polluted with political extremism? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/70dip2/eli5why_is_the_internet_polluted_with_political/ | {
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"It is because of anonymity and abstraction. People say things on the internet that they would never say to each other in person. The first reason is because their comments are anonymous. They perceive that there will be no repercussions for what they say, so they can say whatever they want and no one will find out that it comes from them. The second is because of abstraction, which means that the people that they are attacking are not really people, they are just an abstract entity on the internet whom they will never meet and to them are not a real person.\n\nI believe the internet is the reason behind the rise of the Tea Party and now the white supremacists. Online they could talk all of the shit they wanted and they got each other all revved up. But if you look at the Charlottesville protests, you could see how quickly they tried to backtrack their stances once they realized that their identities were now known and being publicized. That's why the KKK wears hoods. The internet has been their modern hoods and they made the mistake to take them off and March in person in the daylight."
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4uhslp | when coming to a stop in a car, why do the brakes suddenly grab at the end? | Specifically speaking, if one was to hold the brakes at a constant pressure during deceleration, when the car comes to a rest, why do the brakes suddenly grab and make the car lurch at the final moment rather than easing to a stop? (Making people have to lift pressure at the end of a stop) | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4uhslp/eli5_when_coming_to_a_stop_in_a_car_why_do_the/ | {
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"Basically, when applying the brakes at a constant pressure, you apply constant torque to the wheels which will give you constant deceleration of your car i.e. you lose X amount of speed for every second. \n\nAll of that applies as long as your car moves, so you feel a deceleration until the car stops and suddenly you don't feel it anymore - that's the jerk you feel when the car gets to a sudden stop. \n\nTo prevent that, when your speed is really low your ease down on the breaking to bring the car to that halt more slowly than with a constant breaking applied. ",
"Coulumbs law of friction states that the kinetic friction is independent of velocity. I don't think it is an increase in friction during the end of retardation. Rather a negative acceleration you feel when the suspension, rubber in the tires and your body goes back to a relaxed state just after the car comes to a halt."
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cbqssa | we do we sometimes not crave specific foods, but at other times we crave that same food? | Like if right now I want some Taco Bell, but on a different day Taco Bell’s sounds disgusting. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cbqssa/eli5_we_do_we_sometimes_not_crave_specific_foods/ | {
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"It all comes down to what nutrients your body needs. Take an orange, for instance (not the best stand-in for a taco, but it'll work.) Oranges are high in Vitamin C, so if your body starts running low on Vitamin C, that orange you pass in the grocery store is suddenly going to look *really* good. If your body really needs fat and salt, you're going to be rushing for whatever's the closest source of fat and salt, even if you don't feel that hungry. The same goes for protein, sugars, any vitamin or mineral, antioxidants, folate, or anything else your body needs. It's even true with water; if you're slightly dehydrated but you don't feel thirsty (like an astonishing number of people in the US today,) and someone sets down a glass of water and you take even one sip, that water will be gone before you have any idea what just happened, because your body knows that it needs it.\n\nThat's also why pregnant women have such bizarre cravings; they're building a human, and as soon as they need some different building blocks to work with, their bodies start screaming for something that has that thing in it (like pickles and milk duds, which is one that I heard that might be apocryphal.)\n\nThat's the normal way that cravings work, and it's the way yours likely works assuming that Taco Bell doesn't put anything in their food to increase the addictive appeal of it. But, nah, all fast-food places are upstanding and honest, right? No one puts crave-inducing agents in anything they're trying to sell a lot of.... Nope, not ever."
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93mdy9 | how are vines for seedless grapes planted if there are no seeds to plant them from? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/93mdy9/eli5_how_are_vines_for_seedless_grapes_planted_if/ | {
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"Most likely grafting and cloning. Taking a green cutting from a plant, you can root it and grow another identical plant. That's how a lot of commercially grown fruits are made. Apples come to mind."
]
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||
6q38m7 | why are macs always used in adverts, instead of anything else? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6q38m7/eli5_why_are_macs_always_used_in_adverts_instead/ | {
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"Apple probably pays them to use Macs as it a form of advertisement for them. So when they are getting paid for it , the and companies are only too happy to use Macs on their ads. Also it might be because a Mac is widely used in the country where the ad is airing and if it is a software ad they need to show that their software is compatible with a Mac. Hope this helps",
"I always assumed it was the large role the Mac has traditionally played in advertising and design. For the people who came up with the ad, it's probably the only computer they really are familiar with.\n\nAnd in cases of print ads or the like, the designer can literally design the \"on screen view\" using their actual computer or perhaps their own laptop in a photo shoot. When I worked in advertising, we would occasionally get calls asking if we had a spare Mac in inventory that could be borrowed as a prop for a shoot.\n\nAt some point demographics may play into it, and they want their ad to subtly appeal to people who either own Macs or see Macs as an aspirational product and they want to associate their product with an Apple product. Wintel PCs were occasionally used as well, but usually deliberately when they wanted to create a \"boring\" business environment.\n\nSource: I worked in advertising for 13 years."
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87wmyg | why do children like stories that rhyme? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/87wmyg/eli5_why_do_children_like_stories_that_rhyme/ | {
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"Why do children like stories that rhyme?\n\nI'll tell you about it, I've got lots of time.\n\nPatterns are recognized even in utero.\n\nSlant rhyme counts too, until your funeral.\n\nGames and stories are tools for the mind.\n\nA way to advance and not fall behind. \n\nAll life is in patterns,the stars and the seasons.\n\nTrolls will be trolls, \n\ntriggering internet vegans.\n\nThe greedy will hoard the poor kids will suffer.\n\nSomeones out there is banging OPs mother.\n\n\n\n\n\n\n\n",
"People like all sorts of patterns. \n\nPoetry used to be the dominant form of literary art in Western cultures for hundreds of years, and back then poetry had all kinds of other structural constraints that defined its quality in addition to rhyming.\n\nBefore the French (simplification) took over English culture, English poetry was mostly alliterative, and rhyming of the first syllables in words.\n\nPatterns are what define visual aesthetic too, even if that aesthetic is culturally defined. \n\nEven art that betrays those patterns works because people have a sense of patterns in the first place. \n\nStructure of any kind is just interesting to us. It’s true of primarily functional design too, from drywall to software.\n\nIt is part of why we’re such a successful animal in the first place. "
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7v0hgp | why does chocolate milk last longer than regular milk? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7v0hgp/eli5_why_does_chocolate_milk_last_longer_than/ | {
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"If you take a look at the ingredient label on chocolate milk, you'll not that it's nit just \"Milk\" and \"Cocoa\". There's a whole bunch of other things in there. This changes the environment in which bacteria could develop, which is what makes milk go bad. \n\nThere's also so much sugar in there that, frankly, you might not *notice* if it goes bad. "
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838pbl | how do soda machines at fastfood restaurants keep soda from going flat? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/838pbl/eli5_how_do_soda_machines_at_fastfood_restaurants/ | {
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"Restaurants don't serve pre-mixed soda like you buy at the store unless it's in a can or bottle. Due to quantity they go through it's cheaper to order it in concentrated syrup form.\n\nA keg/box of concentrated Coke syrup represents hundreds of servings.\n\nSoda fountains mix soda water + syrup on demand at the tap.\n\nEDIT: Soda machines have a keg of pressurized soda water feeding them so the CO2 can't escape.",
"In most commercial operations, the soda is actually stored in two parts - the flavoring syrup and the carbonated water. When it is dispensed from the fountain, the two are mixed together in the right proportions to make your drink.\n\nThe carbonated water is stored in pressurized tanks, so it doesn't go flat while it is being stored - the CO2 can't escape from the liquid until it is dispensed at the fountain.",
"This is close, but a little off. I work in large scale sports stadiums doing food and beverage. There are actually three parts. The soda syrup or BIB (bag-in-box—industry lingo) a water line (un-carbonated) and a line of C02 gas. The CO2 mixes with the tap water first and then is transferred to the fountain unit where the soda actually dispenses. There an “ionizer” (its a little cap on the nozzle) spreads the now carbonated water and syrup evenly for dispensing. I’ve never come across a unit that has a carbonated water keg and a syrup dispenser. I’ve only ever bought the syrup and the CO2 gas in a cylinder. "
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l84rh | linux/unix | I have used Windows all my life and have no idea what Linux/Unix is and what it's good for or how it's different.... | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/l84rh/eli5_linuxunix/ | {
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"[Here is a great introduction.](_URL_0_)",
"Unix is an operating system for computers that started it's life back in 1969 at Bell Labs. It was designed to allow multiple users to share a computer at the same time. \n\nIn about 1991 a guy named Linus Torvalds took a version of the Unix operating system and modified it so that it could be used for commercial purposes too (It was called Minix and was for research only). Thus began Linux.\n\nLinux is great for many things, and also has some disadvantages. For the average user, a Linux experience using a distribution like Ubuntu wouldn't be too different to using Windows or OSX. \n\nA great strength of Linux is that if you have the skill and desire to change something, you can. Some people place a very high value on this ability.\n\nAnother strength is that there is a lot of free software available on Linux (although much of it is also available on Windows). Certain setups that could be quite costly to run on a Windows machine can be run for free on a Linux machine.\n\nOne of the major disadvantages is compatibility. You standard Windows programs won't run. You may encounter trouble if you use unusual hardware. Drivers for Linux that allow the computer to make full use of things like video cards sometimes lag behind their Windows counter parts. Although you can often work around these issues to get said piece of hardware working, the solution is often quite technical. ",
"[Here is a great introduction.](_URL_0_)",
"Unix is an operating system for computers that started it's life back in 1969 at Bell Labs. It was designed to allow multiple users to share a computer at the same time. \n\nIn about 1991 a guy named Linus Torvalds took a version of the Unix operating system and modified it so that it could be used for commercial purposes too (It was called Minix and was for research only). Thus began Linux.\n\nLinux is great for many things, and also has some disadvantages. For the average user, a Linux experience using a distribution like Ubuntu wouldn't be too different to using Windows or OSX. \n\nA great strength of Linux is that if you have the skill and desire to change something, you can. Some people place a very high value on this ability.\n\nAnother strength is that there is a lot of free software available on Linux (although much of it is also available on Windows). Certain setups that could be quite costly to run on a Windows machine can be run for free on a Linux machine.\n\nOne of the major disadvantages is compatibility. You standard Windows programs won't run. You may encounter trouble if you use unusual hardware. Drivers for Linux that allow the computer to make full use of things like video cards sometimes lag behind their Windows counter parts. Although you can often work around these issues to get said piece of hardware working, the solution is often quite technical. "
]
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7wax6l | when did big dicks become “a thing”. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7wax6l/eli5_when_did_big_dicks_become_a_thing/ | {
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"I'm pretty sure small dicks meant you were smart and stuff in older times. That's why a lot of nude paintings and statues depict famous men with small penises. ",
"Don’t know when it became a thing, but I know that the Greeks didn’t consider it a desired trait. Hence, the reason for the more modest packages of various statues and works of art. "
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5u0wa4 | what exactly are we smelling when we breathe in a nice or unpleasant fragrance? is it the actual bacteria that comes when someone passes gas, or just air particles filled with chemicals that pass through our nostrils? | Sorry if this is worded weirdly. Someone farted on the train today and I wanted to know what foul part of them was forcing its way up my nostrils, particularly since we can't "unsmell" things once we detect them. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5u0wa4/eli5_what_exactly_are_we_smelling_when_we_breathe/ | {
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"Your nose in an incredible machine. Smells come in a variety of chemicals, but the most common are ethers (usually nice smells) and carboxylic acids (nasty smells). Sometimes bacteria will make your nose itch and you'll sneeze, but for the most part you are smelling the chemical excrement of bacteria or dead bacteria, not so much the bacteria itself. Your nose will pick these chemicals up with receptors called the 'olfactory system' and, in physiology (for the most part), once a receptor has been activated you're brain will 'filter out the noise' the receptor is making which basically means your brain knows the smell is there and it slowly deactivates the receptor because your nose does not have the ability to break down these chemicals/bacteria, only catch them in the mucus and boogers your nose makes.",
"Smelling and tasting are more or less chemical senses - in the sense that they react in a chemical way to a chemical compound.\n\nYou don't usually smell or taste bacteria, but the toxins or other waste they produce.\n\nFarts can have a lot of different things in them that smell bad. Smell could be caused by bacteria or fermentation. In farts we usually smell the sulphur compounds which are likely caused by fermentation in the gut or later in digestive system.\n",
"One thing that needs to be added. Just because you are smelling the by products of the bacteria and not the bacteria itself doesn't mean that the bacteria isn't there. You could still have that in the mix, your just not detecting it directly. You can argue that part of the reason why the smell is unpleasant is because it suggests the presence of bacteria and therefore the risk of getting sick. We developed the defense mechanisms of smelling the bad smell and being repulsed by it to protect us against bacterial overload. \nSo you could still be getting some of that butt bacteria in your nostrils. The bad smell that your nose is reporting is your body telling you: \"Stop breathing, high risk of bacteria\"\nLuckily for you there were some clever fellows with petri dishes and they tested this exact thing. Turns out that clothing filters out the bacteria from your farts and what you are smelling is in fact only chemical in nature. Whew!\n\n_URL_0_\n\n\n"
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dsjncr | why are we evolving technologies at such a fast pace now a days, when contrasted to the thousands and thousands of years it took humans to move on from stone tools? | Is it just like a big domino effect? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dsjncr/eli5_why_are_we_evolving_technologies_at_such_a/ | {
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"It's basically an exponential process. That is, earlier gains make future gains easier.\n\nFiguring out how to do more things make it easier to gather enough food for folks, makes it easier for them to communicate, etc.\n\nThis frees up more time for people to come up with new ideas and makes it easier for them to collaborate, etc.",
"Technology is exponential. The more new technologies that are invented, the more tools you have to create never ones. \n\nEverything we have now relies on several inventions, cultural changes and scientific discoveries, but you can't start at the wrong end. You have more avenues to explore, more options, more ideas that can be made reality when you have industrial society than when you had barely figured out metalworking.",
"1.\tDomino effect as you say - some inventions are needed to enable others\n2.\tEducation and social attitudes - far more people can read/write, there's a huge amount of knowledge available, superstitions and attitudes like \"you'll work the field like your elders did or you'll get the cane\" are dying\n3.\tWealth and demand - I know that if I build that cool product there will be millions of people willing and able to buy it. 1000 years ago I could only reach the next village and people could only pay me in turnips - there's no way to accept turnips on Shopify",
"It's worth noting that there are many more people alive and inventing now than at any point in the past.",
"A lot of answers missing the point here. Technological advancement isn't magic, where the more that has been invented, the more will be invented. The driving force is the availability and spread of information. Thousands and thousands of years ago, hardly anyone could read and even fewer people could devote their time to writing, and if you were a professional scribe, the only people willing to pay you to write were merchants needing receipts, clergy needing holy texts, and nobility who needed to send messages. \n\nWith the introduction of printing technologies and recently things like the internet, along with the explosion in literacy rates over the past couple centuries, the flow of information has allowed so many more people to learn, experiment, and innovate than was even imaginable ten generations ago.",
"Technology is slowing down in many regards. What many people view as \"technology\" is actually just globalisation. For example, in the 1960s we landed on the moon. Everyone thought we'd have flying cars by the year 2000. Instead, we have Twitter. Computers arent new technology, they're just getting smaller, faster, and more powerful. But it's just improvement...not new.\n\nI know this is a contrarian view, but I find it to be worth noting."
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3c5t2p | how did factory workers in the 19th century work 12 hour shifts 6 days a week. | For me and I'm sure for most people even just 40 hours 5 days a week is very tiring and 72 hours would be almost impossible especially considering how much more manual the labor was back then. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3c5t2p/eli5how_did_factory_workers_in_the_19th_century/ | {
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"In order to keep their jobs and not starve they did it. Often they got very ill or died from exhaustion. ",
"It was very tiring for them too. but if they wanted to take a break someone else was always waiting in line to take their job around so they basically just had to do it till they couldn't anymore then hope their family didn't starve to death too too fast. \n\nAt the same time LOTs of people in the US do it right now, they just work 2 or 3 jobs instead of working one job for 12 hours. ",
"Your body adapts. People still do work those kinds of hours and even more. At one point a couple years ago I was working 12-15 hour days (and the rare 24 hour day) for several weeks at a time without a day off. "
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4hhcca | how does light pollution prevent us from seeing stars? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4hhcca/eli5how_does_light_pollution_prevent_us_from/ | {
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"The light from the stars is very faint. The light from cities, streetlamps, and so on, washes it out. While you may not be looking directly at the light source, it is scattered in the atmosphere. This means that, similar to the blue sky during the day time, wherever you look light is coming at your eyes and fainter stars are hidden.",
"A simple analogy: when you are in a car in the night with the lights on and someone is approaching you directly with a flashlight in their hands you See their light but it's very dimmed. \nNow if you switch on highbeam you won't See the light at all. Because your local light source from the car is more powerful than their tiny flashlight. \nWith out the lights off on your car you get a can See the flashlight perfectly. \nWith light pollution the area around you has a stronger lightsource than the Star, which is a few million lightyears away, causing the local light source to overpower the more distant one. This is also the reason why more recent telescopes are built around areas where there is not so much Population. ",
"Air is full of things like dust and water droplets.\n\nLight from terrestrial sources illuminate those things floating in the air, give the sky its own brightness that washes out faint objects like stars."
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6j4rw7 | if photons are much smaller than electrons, why can we see better small things with electrons than with photons? [physics] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6j4rw7/eli5_if_photons_are_much_smaller_than_electrons/ | {
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"Photons and electrons are both elementary particles, so they don't really have a size. They couple to other particles as if they were single points.\n\nTo determine what you can \"see\" with a given particle as a probe, the relevant length scale is the de Broglie wavelength of the particle. This is not intrinsic to the particular type of particle, it depends on the momentum of the particle.\n\nThe de Broglie wavelength of any particle is given by h/p, where h is Planck's constant and p is the momentum of the particle.\n\nSo an electron and a photon with the same momentum have the same wavelength.\n\nIf you replace the momentum with the energy of the particle, for a photon the de Broglie wavelength becomes hc/E. For a nonrelativistic electron, it becomes h/sqrt(2mE).\n\nThe ratio of these quantities for a photon and electron at a given energy is c\\*sqrt(2m/E).\n\nAt low energies, this quantity is large. That means that the de Broglie wavelength of a photon is larger than that of an electron with the same energy. A smaller wavelength means a better probe, so electrons tend to have smaller de Broglie wavelengths than photons at reasonable energies.\n\nSo electrons of these energies make better probes than photons if you want to see very small things."
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3eq31n | why do people write graffiti on other people's property instead of their own property? | Answer: it's "fun".
[No wonder I don't understand it. Get off my lawn!] | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3eq31n/eli5_why_do_people_write_graffiti_on_other/ | {
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"Because this\n\n_URL_0_\n\nis more fun to tag than this\n\n_URL_1_\n\nEdit: Graffiti is a sort of counter culture. It goes against this corporate white washed world we all find ourselves sitting pretty in. But truth be told, it's any number of reasons from desire to create, peer pressure, boredom etc. At the end of the day, other people's stuff is usually bigger, and easier to colour than your own.",
"Heh? Because people are c*nts. Why do people do anything? ",
"Most graffiti \"artists\" do not own any property. They tend to be young males with little money (although there are, of course, exceptions). \n \nSo if they want to make graffiti, they must do it on other people's property. \n \nAnd if they did own the property, it wouldn't be graffiti. It would be \"art\". ",
"To be seen by other taggers. They appreciate other work by taggers as well. They call it \"getting up\". The better the placement of the tag, the more they can get \"fame\". Some are in some very dangerous places like billboards or highway bridges. "
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aqwskl | why is crying physically exhausting? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/aqwskl/eli5_why_is_crying_physically_exhausting/ | {
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"I’d say it’s not physically exhausting but instead it is mentally exhausting.\n\nYour brain secrets a lot of chemicals when you are very emotional. When you are upset and crying you brain runs low and needs to replenish. You brain makes you feel tired so it can rest."
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a1lu23 | what's the pourpose of kilowatt-hours and ampere-hours measurement units? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a1lu23/eli5_whats_the_pourpose_of_kilowatthours_and/ | {
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"Regurgitating [a comment I made in /r/electricians a while ago](_URL_0_):\n\nKilowatt-hour (kWh) is a unit of energy. The SI unit of energy is indeed a joule (J); 1 kWh = 3,600,000 J (or 3.6 MJ). kWh is used especially by electrical utility companies for billing purposes because at that scale and as a unit of energy related to hours it's much easier to relate to home electrical consumption. If you leave a 60 W lightbulb on for eight hours overnight it's 1,728,000 J of energy being consumed (60 W x 8 h x 60 min/h x 60 s/min); that's far more cumbersome math than 0.060 kW x 8 h = 0.48 kWh. As such, for the sizes of electrical loads one deals with in a home, it's much easier to relate how much a monthly energy bill of (e.g.) 300 kWh is, rather than 1,080,000,000 J (1.08 GJ).\n\nAmpère-hour (Ah) is a unit of *charge*; the proper SI unit for this is actually coulombs (C; 1 A = 1 C/s; 1 Ah = 3,600 C). Battery charge capacities are often expressed in Ah or mAh because a unit expressed relative to hours rather than seconds is more useful when one is using a device for hours. Even so it's often just to make it easier to market too; a cordless drill with a 5 Ah battery is much easier to express to a consumer than 18,000 coulombs, because a consumer has likely never even heard of the unit 'coulomb', or might confuse \"18,000 C\" for \"18,000 **°C**\"."
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7u4svx | why is it impossible to increase the volume as far as the speakers allow it on youtube, smartphones etc? | As in, why do volume adjusting bars have a maximum even though different files will still not be equally loud at it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7u4svx/eli5_why_is_it_impossible_to_increase_the_volume/ | {
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"Because the volume slider goes up to a maximum decibel level, but the videos themselves have different recorded volume levels that the youtube player isn't going to adjust. It's the same principle as if you had someone sit at a table with a microphone recording at the table, and then a person standing at the opposite end of the room speaking towards the microphone at the same volume. When you play it back, regardless of the device, the person standing at the opposite end of the room is going to be quieter.",
"The volume of the sound at each point in a digital audio track is a number in a fixed range (0 to 65,535 for 16bit audio) with the middle value being “silence” since a sound wave swings in both positive and negative direction.\n\nMany audio tracks are not properly “normalized”, meaning that their loudest points are not at the extreme ends of that range, making the entire track less loud than it could be. Many videos you’ll see these days, especially amateur recordings, did not go through audio normalization.\n\nEdit; sometimes, not normalizing audio can also be a deliberate choice. You wouldn’t want the quiet intro of an album to be at max volume relative to the other songs for example."
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8a3c1f | the logic of beer calories | So I've been counting calories for a while now, and the one thing that continues to baffle me is how inconsistent and confusing the calorie count of beer can be.
Normally I assume if a beer is heavy, full\-bodied, and sweet \(the kind I typically like\) that it will be much higher in calories than something more crisp and mild. Yet time and again I'm left completely confused when I realize that sweet bourbon barrel ale \(with 190 calories per 12 oz\) has far fewer calories than a basic blue moon \(171 calories per 12 oz\).
And that's just a mild example. There's a beer I tend to drink called Golden Monkey. It's a bit on the sweet side, but far less so than the bourbon barrel I listed above. It's also much lighter on the palette. So imagine my surprise when I find out it has 274 calories per 12 oz bottle.
So what's the logic behind this? What sort of weird chemistry goes into the nutritional value of beer? How can I get a rough idea of how many calories I'm taking in at the bar? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8a3c1f/eli5_the_logic_of_beer_calories/ | {
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"Alcohol itself has calories, so higher ABV beers will almost always have more calories than lower ABV beers. Golden Monkey, at 9.5%abv, has a lot of calories.\n\nBourbon barrel stouts, being both fuller-bodied and higher abv than most beers, generally have 300+ calories per 12oz. I don't know which brand of stout you're looking at specifically, but it's possible that either your calorie information on it is wrong, or that it's some sort of light stout.",
"Alcohol contains a lot of calories, so the biggest indicator of how many calories will be in a beer is the alcohol by volume (ABV). 3.2% beer is going to have much fewer calories than some 10% bottle.\n\nBesides the alcohol content, various carbohydrates contribute calories. This is much more complex - the original grain used, the brewing process, and whether anything is added or removed. Lite beers have had many of the carbs removed, which reduces caloric content while maintaining ABV.\n\nChemicals which make a beer dark or rich-tasting generally contribute a negligable amount of calories, so how dark or \"heavy\" a beer is isn't really correlated to calories. Sweetness is (usually) derived from sugar content, which is of course calorific... but less-sweet beers may have simply had their sugar converted into alcohol, which has more calories.\n\ntl;dr: Check ABV first, but beyond that it's impossible to tell because the chemistry is too weird. Do research on your phone prior to ordering if calories are a concern!"
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19a0e9 | what is understeer and oversteer? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/19a0e9/eli5_what_is_understeer_and_oversteer/ | {
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"Understeer is when your car isn't turning enough, relative to how far your steering wheel is turned. This happens when your front wheels slip.\n\nOversteer is when your car turns too much, compared to how far your steering wheel is turned. This happens when your back wheels slip. ",
"* Understeer is where your car doesn't turn as much as you would expect by looking at the angle of the wheels. You have insufficient grip *at the front wheels* so you essentially skid forwards a little bit, instead of simply turning.\n* Oversteer is where the back end of your car slips out a little when you turn. You have insufficient grip *at the back wheels* so the back carries on going forward while the front of the car turns properly.",
"**Understeer:** You are driving down the road, turn the wheel but the car goes straight on, off the road, crashes into a tree and you die\n\n**Oversteer:** You are driving down the road, turn the wheel but the back of the car spins round, you go off the road backwards, crash into a tree and you die.\n\nOversteer is obviously best because you don't see the tree that kills you. *Source: TopGear*",
"While turning:\n\n- oversteer: your car rotates more than you tell it.\n- understeer: your car rotates less than you tell it.",
"_URL_0_\n\nmost helpful ",
"Best way I heard it:\nUndersteer is where you hit the tree with the front of the car, oversteer is when you hit the tree with the back of the car, horsepower is how hard you hit the tree and torque is how far you drag it. "
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1kcg47 | how can people without insurance who are taken to the er after having a heart, stroke, car accident etc be required to pay their hospital bill when they're unable to consent to any of the services being performed? | I recall going to the ER in college and signeing a form consenting to paying my bill for any services performed. How can people who are unconscious be forced to pay for something they never agreed to. Can't they just say after the fact that they never agreed to anything and would have been happy to have been left dying on the side of the road.
Edit: A lot of answers seem focused on the obligations of doctors and hospitals. What I'm asking about is what are the obligations of the patient. If emergency rooms have to take everyone regardless of ability to pay, why would anyone ever pay for treatment they never consented to? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1kcg47/eli5how_can_people_without_insurance_who_are/ | {
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"Because in the absence of contrary information (a medic alert bracelet saying \"let me die\"), society (and the law) has decided that basic, minimum care to preserve life is the default standard. So you are therefore liable to pay for the service.\nThe opposite would to be require consent at all times from injured before doing anything. Considering that the more serious the injury, the higher the likelihood of not being coherent or awake, a ton of people who would otherwise be save would instead, die.",
"Five year old, I am not a lawyer. \n\nA federal law called the Emergency Medical Treatment and Active Labor Act (aka EMTALA) created in 1986 and revised in 2003 basically requires a hospital to treat you once you've arrived, and restricts the hospital's ability to discuss payment before services are rendered. Most state or local laws govern the practice of Emergency Medical Services, and legally require the ambulance people to treat and then transport you to a hospital if you're injured and unconscious. \n\nSo, let's say you've been hit by a car and you're lying unconscious by the side of the road, and someone dials 9-1-1 and the fire department arrives on scene. One law probably mandates that the EMS crews transport you to a hospital. Another law requires that the hospital treat you once you're 250 yards from the building. And that same law makes it illegal for the hospital to delay your treatment while determining if you consent to pay. Several court cases have decided that hospitals (e.g. for-profit) must treat you and not dump you off at another hospital (e.g. charity) that might be less concerned about your ability to pay. \n\nAlso, if you have a pre-determined legal \"Do Not Resuscitate\" order -- different hospitals might have different policies about how they honor that. To avoid lawsuits and comply with state or federal law, hospitals might have to treat you against your pre-decided consent until a family or friend brings a copy of that document. \n\nThe laws mandate that the treatment providers treat you without your consent regardless of your ability to pay. The laws also let them, later, seek payment for those services rendered regardless of your ability to pay.\n\nTL;DR: Because, it's the law. \n\n",
" > Can't they just say after the fact that they never agreed to anything and would have been happy to have been left dying on the side of the road.\n\nAnd, say, one of your loved ones was unconscious because of anaphylaxis, and every single medical personnel next to her just stood around and did nothing because no one was there to give consent for her - even though all one needs to pay for is an epi-pen and the time of the emergency worker (which you can easily afford).\n\nIs that system better?",
"Among some of the other comments that mention the laws that apply here. I believe that the Hippocratic oath taken by Dr's obliges them to save a persons life. Medical aid cost's money, so someone has to pay for it. And, Unless one has a DNR (Do Not Resuscitate) I'd think one would be rather grateful that their life was saved regardless of the cost. ",
"I work ems and its legally called \"implied consent\". Basically we are allowed to provide any treatments that a completely rational adult would want. Same goes for treating a minor when there parent isnt present. Its Implied Consent.",
"I need you to clarify what country you're asking about, because if I were a Canadian I'd be sitting here thinking \"this question makes no sense.\"\n\nSadly, I'm from the US, and I know exactly what you're asking. Yes, they would have to pay. Basic care will be provided without consent.",
"Here's a tangential question: What happens if you just don't pay?",
"This is especially difficult for mental patients, who can be \"required\" to pay tens of thousands of dollars for involuntary hospital stays.",
"Because if I'm a doctor and you come into the hospital in cardiac arrest and I say \"I'm not touching him until I see insurance paperwork, or get consent from a living relative\", and you die....then I look like a shitty person.",
"The question itself is a philosophical failing and trick. It's very premise is absurd: that one would not want life saving treatments in order to save some amount of money. \n\nThink about what you're really asking for a second, to be left to die so that you don't have to pay for a bag of blood, a thread and needle, an electric jolt or some chest staples. \n\nThe reason you consent to the treatment is because we all consent to it, as a society, as a culture we've decided that we would rather be rescued and pay the appropriate associated bill rather than die at every life threatening injury or trauma. ",
"This is most definitely a loaded question and no amount of answers will justify your 'query'. It can be answered simply enough, **you have to pay for the services rendered.** \n \n But then your rebuttal contains, \"well they could have left me for dead, I didn't want to be rescued anyway\" BULLSHIT! Ask me that question again when you or your loved one is the one dying! That sounds like what someone would say to avoid payment! Whoever that unconscious person is, that's someone's father, mother, wife, husband, or child. The ethical thing to do is to cure them, regardless of the situation. ",
"Why not just do a quick credit check on everyone rushed to the emergency room and if they don't pass then put em back where you found em.",
"The theory is that a person in that situation would want their life saved so the law presumes that you consent to the treatment.",
"A lot of soapbox stuff here....the legal answer in the US is called \"implied consent\". It's the law that states any reasonable person would consent to life saving treatment if they are not alert and oriented and able to communicate their need. It's the law that allowed EMS/ERs to treat these types of situations. It's also covers treatment for minors when a guardian isn't around to agree to treatment. \n\nIn the US a law was passed in 1986 that requires ERs to treat all life threatening conditions and active labor regardless of ability to pay\n\n_URL_0_\n",
"In an emergency situation, consent is implied and is not required by law. That's why when someone is choking at a restaurant and they don't consent to you doing abdominal thrusts on them you should wait for them to pass out and then proceed to do CPR.\nSource: I'm a nurse."
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6zpj7z | why do washing machines have concave glass doors instead of flat glass doors? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6zpj7z/eli5_why_do_washing_machines_have_concave_glass/ | {
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"Two reasons, assuming a front loading washing machine:\n\nFirst, the concave glass window pushes inwards on the rubber water seal. This makes it so that clothes that hit it push the seal further into the glass rather than have the possibility with a flat window that the clothes peel the seal from the flat surface of the glass (causing a water leak).\n\nSecondly, the concave glass helps push the clothes in the washer around as it's spinning to help agitate the clothes (clothes will bounce off it and be pushed further back). With a flat window, there's a possibility the clothes end up stuck spinning next to the window, never moving away from it. Because the clothes are not moving, they do not get a good wash!"
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4406td | did people of all nations involved in the cold war call it "the cold war"? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4406td/eli5_did_people_of_all_nations_involved_in_the/ | {
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"The USSR and it's satellites most definitely viewed themselves as a bloc of nations opposed to a US led bloc and in a state of subdued conflict with one another. People in non-aligned countries definitely felt pressure to pick a side and became the most frequent places where the cold war opened into actual conflict. I don't know whether or not the term \"cold war\" was used elsewhere, but the conflict was viewed as a conflict and in much the same way.\n\n > Also, I do have one more question, are we really that close to a Second Cold War and if so, do you think that will be its name?\n\nRussia isn't the USSR+Warsaw Pact+pre-1969 China. Also, relations with Russia are bad, but not that bad compared to where they were during the cold war. Russia doesn't promulgate an ideology that views itself in conflict with Western Democracy and Capitalism. \n\nThe above also applies to China except that relations with China are better and China has a greater interest in good relations with the US and the rest of the world than Russia, so it makes even less sense as a \"cold war opponent.\"",
"If you go to the Wikipedia article on the Cold War, it links you to the Cold War article in other languages. Just browsing through, I see the Germans call it \"Kalter Krieg\" (Kalter = Cold Wind, Krieg = War), in Spanish it's \"Guerra Fría\" (Cold War), Italian is \"Guerra Fredda\" (Cold War). And according to online translation, the Russian \"Холодная война\" translates as Cold (Холодная) War (война). \n\nWhether or not these names were contemporaneous with the Cold War itself, I cannot tell you. ",
" > Did people of all nations involved in the Cold War call it \"The Cold War\"?\n\nYes, in Russian it's also called Холодная война, which means exactly the same.\n\n > did people actually know it was a Cold War and call it that? Or did it receive it's name after the fact? \n\nThe term \"Cold War\" appeared as early as 1945, and became widely spread in the next several years.\n\n > are we really that close to a Second Cold War \n\nNot really. There's not so much tension between countries and they don't have rival ideologies."
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4d0hdf | how is the power of an irrational number calculated? | I was always taught that if a exponent is a fraction, then it becomes a square root (for example: 2 to the power of 3/7 equals the seventh root of 2 to the power of 3). So what about decimal numbers that cannot be made to fractions? For example, how is a number to the power of pi calculated? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4d0hdf/eli5_how_is_the_power_of_an_irrational_number/ | {
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"With a Taylor series. There's a method using calculus where, for most functions, including, say, f(x) = 2^x , you can find an infinite series, like\n\na_0 + a_1 x + a_2 x^2 + a_3 x^3 + ...\n\nthat's equivalent to the original function. And that series is (for our familiar kinds of functions, like exponentiations) easy enough to compute.\n\nWell, it's not always easy to do the arithmetic and work out the answer to twelve decimal places, but you get enough mathematical information that you can, at least in principle, nail it down to a specific number.",
"Here is an idea: \n\nAny irrational number can be arbitrarily well approximated by a rational number. \n\nSo to calculate 2^pi you take a sequence of rational approximation to pi and calculate the successive value of 2^rational number for all of them. \n\n\n\n*continuity * guarantees this will converge to 2^pi. \n\nThe implementation strategy is clear except for the fact different sequences will be useful for different degrees of precision...."
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2y7z9n | why do we still not have a cure for headaches and migraines? | Headaches and migraines are suffered by (likely) billions of people with varying frequency. Obviously we have pain killers, but I mean that we still have trouble explaining exactly what causes (triggers) headaches and migraines. We can only give people vague advice like "drink less coffee and you'll likely get fewer of them". | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2y7z9n/eli5_why_do_we_still_not_have_a_cure_for/ | {
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"From my understanding the large majority of headaches are stress related so I guess the cure for those could be Prozac or something similar. Other types of headaches have a long list of causes so if you wanted a cure it would be like curing the common cold",
"One reason is that we are finding it very hard to create safe and effective analgesics (pain killers) . Most of the stuff you get without a prescription sucks and still has side effects. The good stuff however is basically a close relative of heroin(they are opiates) , and are very very addictive. The holy grail of pain meds is a non addictive, effective and low side effect drug. It is very hard to do because if the brain chemistry involved, where the brains natural form of pain reduction is to flood itself with feel good drugs. This is why effective pain killers are so addictive, they mimic this process. \n\nAs to headaches specifically, they are caused by so many different things that effectively treating them is difficult. Is it dehydration? Stress? Depression? Tight muscles in the neck and back? Brain swelling? Withdrawal from drugs? Cancer? Reaction to a substance? Heat stroke? A migraine? Being a very common symptom means there cannot be a simple treatment, and anything pretending to be one is only addressing the symptoms. "
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3ly08u | is there any benefit to trying to go back to sleep when you wake up 15 minutes before your alarm is going to go off? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3ly08u/eli5_is_there_any_benefit_to_trying_to_go_back_to/ | {
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"Most people will be better off just getting out of bed if they naturally wake shortly before their alarm goes off. Going back to sleep may start another sleep cycle, which when interrupted would leave you feeling more tired. The time between falling asleep and starting a sleep cycle varies by person, so this isn't the same for everyone."
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20dqzi | how do nuts raise my hdl cholesterol when the package says it has 0mg of cholesterol? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/20dqzi/eli5_how_do_nuts_raise_my_hdl_cholesterol_when/ | {
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"2/3 of the cholesterol floating in your blood is made by your liver. The nuts stimulates your liver to make more HDL and less LDL."
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cthkfc | how does steam not condense on the inside of our lungs in a place like a sauna? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cthkfc/eli5_how_does_steam_not_condense_on_the_inside_of/ | {
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"For steam to condense you need the right temperature and pressure. \n\nNeither are right inside your lungs or sauna",
"The dew point of sauna air is still below 98.6F - you need to be colder than lung temperature to generate significant condensation.\n\nIt is possible for a dew point to exceed lung temp so that the air is so hot and so saturated that it would theoretically condense on you. This means that your sweat also cannot evaporate, and you'd rapidly overheat in this 100+F saturated air.\n\nYou probably *could* design a sauna to get that oppressively humid, but it would be extremely unpleasant and very dangerous."
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4687tb | my left palm has a straight line instead of two lines. i have not come across any one with this so far. why it is like this? | I have it only on my [left palm](_URL_0_) | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4687tb/eli5my_left_palm_has_a_straight_line_instead_of/ | {
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"I have it that way too. Haven't ever met anyone other than me who does, although another post says it occurs in 10% of the population."
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ap4bwz | what drug do doctors use for anesthesia during surgery? and why do people act like high after the surgery | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ap4bwz/eli5_what_drug_do_doctors_use_for_anesthesia/ | {
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"General anesthesia is a medically induced coma by using anesthetic agents.\n\nMost of the time, coma is induced by a short term anesthetic -like Propofol- but since its action is quite short the coma is maintained with other drugs so you dont wake up screaming in the middle of the surgery.\n\nOnce surgery is over, the « emergence » state begins and drug effects disappear. You are put in post-operative care were you might be administered other drugs to recover wich could lead to dizziness and feeling like shit overall. This is made worse depending on the anesthetic agents used during surgery. \n\nFor local anesthesia there can be some consequences depending on people but it is generally not as bad as far as I know.\n\n"
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29qo9q | how a ant queen can reproduce other ant queens if they normally makes only ant workers | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/29qo9q/eli5how_a_ant_queen_can_reproduce_other_ant/ | {
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"Ant queens produce both male and female ants. A queen ant is just a female ant that leaves its nest, reproduces with a male and begins its own colony - becoming the queen of that colony.",
"Many (but not all ) ant reproduce like honey bees. Queens lay 2 types of eggs fertilized and unfertilized. The unfertilized are all male. The fertilized are female and develop differently depending on how they are fed as a larva. If fed very well it develops fully into a potential queen, if only fed adequately it develops into a worker. Generally workers can not lay eggs only queens can (this does vary in some species). A lot of the development that occurs with better feeding is the development of the reproductive organs.\n\nAfter pupation ant potential queens leave the nest mate and found a new colony. ",
"The type of ant (queen or worker) is determined by how much food the ant larva consumes before developing into an adult ant. In times of low food, only workers are produced. When food is plentiful, some larva get more food than others so that they can develop into queens. This is similar to bees where bee larva are fed a special excretion called royal jelly which makes them develop into queen bees instead of workers.\n\nFemale ants come from fertilized eggs with a full amount of chromosomes (diploid) while male ants come from unfertilized eggs with half the amount of chromosomes (haploid)."
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27tbt9 | how medicare/medicade is not the same a socialized or government funded healthcare? (i am not american) | I frequent the different subreddits sites here a lot and someone asked how low income people can have so many children if the cost of delivery and hospital stays were so expensive and many people said that if you are low-income it;s all covered by the government.
A poster in personal finance wrote about how his parents both had cancer and had tremendous bills and the most popular suggestions were to get the parents onto Medicade, as it would cover all their costs.
I understand for the wealthy they need to cover their own bills, but is it true that if you are low-income your medical stuff is covered by the government? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/27tbt9/eli5_how_medicaremedicade_is_not_the_same_a/ | {
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"Yes, to a degree. Medicare is for the elderly, Medicaid is for the poor. Both are essentially government-funded single-payer systems. "
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4ccddh | do elderly women lose height when they grow older and if so, why? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4ccddh/eli5_do_elderly_women_lose_height_when_they_grow/ | {
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"Not just women. The last time I looked it was reckoned both sexes start to lose about 12mm per year after the age of 40.\n\nChanges in muscles, joints and posture account for it.\n\nThere is a particular problem in elderly women with osteoporosis which is a weakening of the bones due, IIRC, to decalcification. The best way to prevent it seems to be ensuring you have plenty of bone density to spare before it starts.\n\nEDIT - **per decade!**",
"Not only women, men too. Most of the height loss is due to wear on the intervertebral discs. In some cases of old people the discs aren't even present anymore. The discs are mostly made of cartilage which heals very slowly. When you get older the healing process itself becomes slower and at a certain point the discs will decrease in size due to wear. ",
"Everyone looses height as we age due to the compression of the disks in our backs, and the arching of our back. \n\n.\n\nYou are actually shorter at the end of the day, than when you woke, due to gravity compressing your spine. (It is why astronauts are taller after missions)\n\n.\n\nThis is exemplary in aging women because of a greater risk of osteoporosis (a loss of calcium in the bones) increasing both compression and arching. \n\nHave a great day! :-) ",
"I'm 55 years old, and I was 6'0\" for most of my adult life. In 2014, they measured me before surgery, and I was 5'10\".\n\nGo figure. "
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1u3u5f | if ginger hair started as a mutation, couldn't we purposefully 'mutate' genes to give 'natural' blue hair? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1u3u5f/eli5_if_ginger_hair_started_as_a_mutation_couldnt/ | {
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"Probably not. Reds and browns are already produced by our body, mostly in the form of melanin (the same pigment that colors skin). So far as I know, humans don't have any blue pigments.",
"The mutations that led to red and blond hair had to do with production of different types of melanin, which are very similar to the melanin that determines skin colour. [From wikipedia](_URL_0_):\n\n > There are three basic types of melanin: eumelanin, pheomelanin, and neuromelanin. The most common type is eumelanin, and is produced in 'black' and 'brown' subtypes. Pheomelanin is a cysteine-containing red-brown polymer of benzothiazine units largely responsible for red hair and freckles. Neuromelanin is found in the brain, though its function remains obscure.\n\nSo unless you can engineer a genetic alteration that causes a fundamental change in the structure of the melanin molecule, or somehow get the body to produce a completely different substance, then you're never going to be able to introduce new 'natural' hair colours. You're only going to be able to change the relative proportions of black, brown, and red pigments.",
"It might be possible. There are lots of animals with blue pigments in their skin and feathers so that suggests that there's some genes out there that could turn hair blue. We could try splicing one of those genes from an animal that carries it into a human and see what happens! It might just work or it might be incompatible with our other genes. Genes are so complexly interrelated that trying it out is the only way to be sure.\n\nMutating our genes step-by-step to produce blue might be more difficult. It depends on whether there's a sequence of mutations that lead from our brownish pigments to blue without passing through mutations that are bad in some way and cause the cells to die, for example. Think of it like one of those puzzles where you're given the start word and the end word and you have to change one letter at a time to get from start to end but each intermediate step has to be a word too. There might be a path or there might not."
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1nfu9k | why don't armored transport companies such as g4s and brinks use unmarked vehicles? | Just seems to me like they would get robbed less frequently. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1nfu9k/eli5_why_dont_armored_transport_companies_such_as/ | {
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"An armoured car is an armoured car, they don't pull them out for nothing so it's already obvious you're doing some valuable cargo anyway... or maybe just moving it to pick up some valuable cargo.\n\nSo you're already advertizing it, may as well advertize your company while you're at it. It's not like they're robbed much anyway. ",
"How frequently are they robbed? Even if there is an epidemic of armored truck heists they're not really crimes of opportunity (meaning that no one robs an armored truck just because they happen to easily identify one parked on the side of the road). There's at least a little bit of planning that probably goes into robbing an armored truck so I doubt adding an \"identify an armored truck\" item to the to-do list isn't going to add a while lot of work for the robbers since the trucks stand out so much anyway.\n\nI highly doubt removing the logo would make any difference to the rates that they're robbed.",
"I think the question is why not just grab it in your Sedan instead of an armored truck. And the answer is because it would be easy to figure out which car is carrying the money. Scope out the bank for a bit and when you see the guy obviously transporting millions you just shoot up his car and take the money."
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akxkgl | what is it called when you want something you cannot get, but if you end up having it, you no longer want it? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/akxkgl/eli5_what_is_it_called_when_you_want_something/ | {
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"Be careful what you wish for\n\n(or to address the other post, the grass is always greener on the other side \\[of the fence\\])",
"I don't believe there is a term, if anything it's just a part of life moreso than a specific feeling. But psychologically it's based on our brain's tendency to use rewards. When we accomplish something we get a rush of neurotransmitters such as serotonin to tell us we've done a good job. Similarly when you buy the new phone you've been saving up for, you feel a rush of joy but eventually the phone will become mundane and the joy will have gone. ",
"The word \"surfeit\" comes to mind but is not exactly it. \n\nFrom Merriam-Webster: _URL_0_\n\nEdit to add: Verb\n\nSatiate, sate, surfeit, cloy, pall, glut, gorge mean to fill to repletion. Satiate and sate may sometimes imply only complete satisfaction but more often suggest repletion that has destroyed interest or desire: \"Years of globe-trotting had satiated their interest in travel; readers were sated with sensationalistic stories.\" Surfeit implies a nauseating repletion:\"Surfeited themselves with junk food.\" Cloy stresses the disgust or boredom resulting from such surfeiting. \"Sentimental pictures that cloy after a while.\" Pall emphasizes the loss of ability to stimulate interest or appetite: \"A life of leisure eventually begins to pall.\" Glut implies excess in feeding or supplying: \"A market glutted with diet books.\" Gorge suggests glutting to the point of bursting or choking: \"Gorged themselves with chocolate\"."
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7ry92i | in music what is the overtone series, how does it work, and why is it important. | I'm a percussionist that had to learn a few brass instruments for a class and they talked about the overtone series and I had no idea what they were talking about. Please ELI5. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7ry92i/eli5_in_music_what_is_the_overtone_series_how/ | {
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"The overtone series, or harmonic series is the series of tones that resonate with the base tone. They do that when their frequency is a whole multiple of the base tone’s frequency because then every time the base tone’s wave swing in one direction all the harmonic tones do so too.\n\nNot all instruments generate all harmonics, though. A sine wave contains no harmonics while a synthesizer’s sawtooth wave contains all of them. A square wave only has the even ones. Other physical instruments only have certain harmonics which gives them their characteristic sound.\n\nEdit: this is only true for a single oscillator, like one string on a violin, a single flute, or one electronic oscillator. Instruments with multiple oscillators can produce multiple base tones that shape their sounds further, even if just one „note“ is played. E.g. a Piano has Multiple Strings per key and some of them may be slightly detuned on purpose to give it a certain character without only relying on harmonics.",
"There are some examples on the physics theory of this phnomenon, I'll expand on the musical side.\n\nThe interval ('distance' ) between every 2 notes can be defined in several different ways:\n\n1. Tonal: tones and semitones define step sizes between notes, with tones as whole steps, and semitones as half steps. Each interval of notes (in western music) has a unique definition in these terms. \n\n2. By number and quality: unison, second, etc, all the way to octave. Unison means the 2 notes are the same note, a (major) second means there is one whole step between the 2 (like do and re, or fa and sol). Quality includes qualifiers such as minor, major, augmented, diminished and perfect. The difference between them boils down to additions or removals of a semitone or a tone. These \n\n3. Frequency ratio: as a result of the way musical instruments are built, intervals are defined as a ratio between frequency, with the main notes in each scale (the white keys on a piano, for example) being in relatively simpler fractions (with smaller numerators and denominators). So octaves are doubled in frequency, fifths (perfect) are 3/2, thirds (major) are 5/4,and so on. \n\nCombine this with the physical understanding of overtones, where strings, for example, vibrate at whole multiples of their natural frequency (all of them, at the same time) when strummed, and you get a whole lot of notes every time you play one, all at the same time. \n\nThe notes are, according to the whole multiples of the base frequency:\n2 - one octave above the original note. \n\n3 - one octave and perfect fifth (multiple by 2 and then by 3/2). \n\n4 - 2 octaves (multiple by 2 twice). \n\n5 - 2 octaves and a third (multiple by 2 twice, then by 5/4).\n\nAnd so on (these are the main ones you can actually hear, if barely by the last one). \n\n(source - I took music theory lessons in high school, and I might gave forgot a bit) ",
"So all of the previous answers have a lot of good information but in terms of building one, we'll start with our handy French horn. The standard double horn starts on Bb and F (depending on the side that is triggered by the thumb) and it goes in the same pattern as mentioned before Bb1, Bb2, F2, Bb3, F3, Bb4, D4 (slightly out of tune), F4, etc. This is important because then it's just using valves like on a horn, trumpet, etc or adding more tubing like a trombone to tune the pitch. It's also important as a scale, if you take all the notes you get what's referred to as Flat Lydian which contains a b7 and a #4. Bartok liked it and used it in his piece 'Contrasts' for piano trio. Building on the example of bb, the scale is Bb C D En F G Ab Bb. It's a fun scale and is used in jazz often due to it working beautifully over a Bb#11 (implied dominant seven with a sharp four). \nSo we have established that it's important for brass instruments and its composition but it also affects your voice, and your percussion instruments. \n\nThe sounds of each instrument (timbre) is different because it brings out certain parts of the harmonic series called overtones. That's why singers are so focused on resonance where they try to highlight the overtones in their voices. Some instruments have super simple sounds (like a clarinet which is fairly close to a sine wave) or some are really complex (like a violin, which is super fucky). This gets a little more technical but if you're synthesizing sounds using Max/MSP or Supercollider or any electro-acoustic piece, you want to help the two overtones blend—not clash. This becomes really hard with instruments like saxophones or double reeds. It's a super useful tool and helps explain a lot of orchestration technique. \n\nSource: composer in university, focuses on jazz and electronics "
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2fsffs | why do some tv remotes work when you point it in any direction, yet others only work when you're pointing it directly at the tv? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2fsffs/eli5_why_do_some_tv_remotes_work_when_you_point/ | {
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"Radio frequencies (RF) versus infrared signals (IR). IR requires line of sight (LOS), whereas RF just needs to be within a certain distance in order for the signal to be passed."
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bvhboj | how do landmines work and how much damage can they do? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bvhboj/eli5_how_do_landmines_work_and_how_much_damage/ | {
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"Bury a bomb and put the detonator button on top. Boom!\n\nDamage depends on bomb design and the size of the bomb. Fragmentation and high explosive are common.",
"They're basically bombs that you plant in the ground. They can either be triggered remotely, through a trip wire connected to the mine, or with a pressure sensor directly on the top of the mine.\n\nDamage? Depends on the mine type. Anything from blow your legs off to blow up a truck and everyone in it.",
"On top of the mine is a easily breakable cork that holds a \"detonator\", a small metal tube that falls down inside the mine if the cork is broken. When the tube hits the bottom it releases a spark which triggers which then triggers the explosion. The cork is usually carried separately from the mine and placed in place only when the mine is half buried in the ground. \nWell at least this is how anti vehicle landmines work."
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5p4ii2 | where do they get the vitamins and minerals to make multivitamins? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5p4ii2/eli5_where_do_they_get_the_vitamins_and_minerals/ | {
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"The cheapest way possible. They are capitalists. Every few years a new important nutrient is discovered. Guess What? It was not in the packaging of the multivitamin. It might not make it for years.\n\nBut if you eat a variety of fruits and vegetables you will survive as our ancestors did for millions of years before vitamin pills were invented.\n\nJust because a vitamin pill has something in it does not mean you absorb it.\n\nTo get to your question, Each one of these vitamins or minerals can be found in some highly concentrated form. They can be extracted from natural sources or synthesized. I could lead you down the path of chirality but let me make a simple point. Just because a complex molecule such as a vitamin exists, is synthesized to have exactly the same elements attached in the same order, does not mean that the synthetic version has the same shape as what we have been absorbing. It may not work in your body even if absorbed.\n\nOnce all this has been located, extracted, synthesized, and concentrated it must be put in close proximity with the others. Chemicals react. The manufacturer is looking for nonreactive versions. In your body you want them to react. That is why you took the vitamin pill.\n\nVitamin pills are a good alternative if you are gong to be in a very restricted environment with no source of fruits and vegetables. The vegetables do not even have to be fresh. They can be canned or frozen.",
"The vitamins are organic chemicals and are synthesized in laboratories. \n\nMinerals are mined from the earth's crust . "
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eg9bww | what causes that mental notification we get when someone calls our name? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/eg9bww/eli5_what_causes_that_mental_notification_we_get/ | {
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"That feeling comes from the medial prefrontal cortex— a section of your brain that often runs on a sort of dormant autopilot until stimulated by things that you associate with yourself.\n\nThe same part of your brain lights up when you use pronouns to refer to yourself, when you call yourself by your own name, and when you see your reflection."
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1keiqg | if it's bad for the battery for a computer to be plugged in while at 100% charge, why can't the charger detect a full charge and disconnect the power? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1keiqg/eli5_if_its_bad_for_the_battery_for_a_computer_to/ | {
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"It can and does.\n\n(Speaking for Lithium-Ion batteries)\n\nIf it didn't, the battery would overcharge, which would result in the battery failing (possibly catastrophically, read: explosively).\n\nWhat's bad for the battery is remaining at 100% battery for extended periods of time. It can result in the chemicals in the battery becoming crystalized, and unable to discharge. \n\nImagine if you had a bottle of water and ice formed if you left it filled for too long, and that ice never melted. The total drinkable capacity of the water bottle would be reduced by the ice. ",
"My Asus does. I noticed about a week after I bought it that it would sometimes stop charging at 98% and say it's full. I Googled it, and found out it's a safety measure.",
"That's exactly what they do!! \nLong before lithium-ion batteries, when lead-acid storage batteries were not just limited to the transportation industry, as they pretty much arer today, chargers were designed to stop charging at a certain level of electrical resistance. Problem was that the safe level for that was not the same for ALL batteries. ",
"I have a laptop that's usually just plugged in and almost always on 100%. \nSometimes I'll take it into the garden or the forest when I decide to work outside, usually lasts me 2 hours at least. \nSo I'd think there's a safety feature built in to save the battery. \n\nEdit: Utterly confused about why I'm getting downvoted here. Did I break some rule?",
"Newer computers do this, but start to charge the battery again after it falls below some (configurable) value. My guess would be that setting that threshold as low as possible would give the best lifetime to your battery.\n\nWhat I don't understand is, shouldn't there be a setting to disconnect *the battery* and only use the AC power to save the battery cycles, running the computer off AC. This would be the same as running the computer with the battery out and the AC connected. I guess that would suck if you bump the cord or something.",
" A < - B < - > C - > D\n\nSlightly simplified, a battery consists of some stuff in state B. When you charge it you transform it to state C. Discharging will transform state C stuff back to state B. Applying an overvoltage while it's in state C will slowly convert it to state D, which is pretty much unusable stuff. Draining the battery while in state B will convert it to state A, which is also unusable stuff. These two reactions happen least when the battery is halfway between state B and C (ie, halfway-ish charged) because C is easier to discharge than B and B is easier to charge than C, so the \"happy\" reactions are most likely to happen. \n\nThe stuff in state A and D is just taking up space and was usable as capacity. These two cannot be converted back. You don't see much of this at all in the charge; at most as a tiny bit of resistance.\n\nFor the rest, the battery doesn't really have a \"100%\" value for itself. The 0% to 100% scale is a simplified version of the charging graph that gives more usable information for users. Actually, it's a graph that starts at around 2.5V or so, rises really quickly to around 3.3V, goes up at a fair pace to 3.7V, then sloooooowly rises to 4.1V and then shoots up to 4.4V. Below 2.5V everything goes to state A really quickly, above 4.4V everything goes to D really quickly - either reaction will destroy your battery functionally. Overcharging it will also induce an electrical charge that can ignite the D state stuff, making it blow up. To prevent this, most devices only tell you about the 3.3V to 4.1V part of the range and call that 0% to 100%. Your battery can be at (or actually below) 0% for a while after you've left it out in the open drained for a while, after you connected a charger. It's actually below the 0% level so the device says 0% to not confuse you.\n\nNow, when your battery is at 100% the C- > D conversion happens most easily. To prevent destructive overcharging your charger will disable charging until it's discharged to 95% (about) and then charge up again (to 100% ish). The reasoning is that since you put a charger on it, you want it to be at 100% when it's disconnected so you get a long battery life out of this charge. \n\nAlternatively, your battery could be charged to 70% ish (or 3.9V) and then only discharged to 30% ish (3.5V). This would save your battery much more (as you get much less of the C- > D and B- > A conversions) but also eats 60% of your battery charge time. In longer usage-life products this is probably a good tradeoff, but in 2-year (or 1-year) replacement cycle products it's a bad idea as your device won't be sold. \n\n***TL;DR: Your device already does. It doesn't fix that problem. Less charging does, but reduces your battery life by a ton. Your choice.***",
"o GEEZ I really didn't know this.... I ALWAYS keep my laptop battery plugged in. 0.0 that thing never gets below 100% lol..... Been a good 3 years though havn't had to replace it yet.",
"Your laptop DOES detect when the battery is full and it stops charging, in other words you can leave it plugged in all the time no problem"
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5m7agk | why didn't we make seconds slightly slower so that we could have seconds, minutes, and hours in base 10? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5m7agk/eli5_why_didnt_we_make_seconds_slightly_slower_so/ | {
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"\nThe French tried this but it didn't catch on. They tried to use \"decimal time\" (dividing the day into 10 hours with 100 minutes in each hour and 100 seconds in each minute) a couple years before their revolution occurred and people didn't like it. The rest of the metric system stayed and was implemented shortly after the French Revolution. You can still see some influence from metric time, though, in units like milliseconds and nanoseconds. However, the metric system doesn't include standard minutes or hours.\n\nPutting 24 hours in a day came from the ancient Egyptians who split things up into 12, so they made a 12 hour day and 12 hour night. They likely picked 12 because it factors easily (you can divide it evenly by 2, 3, 4, and 6). The 60 minutes in an hour and 60 seconds in a minute comes from the ancient Babylonians who liked to split things in base 60. They had a thing for the number 360 because they thought that's how many days there were in year. They also like 60 because, like 12, it can easily be divided into several other whole numbers. People have been keeping time in these increments since ancient history and it's stuck around since then."
]
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[]
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|
1syajk | how do dog food makers know if their food tastes good or not? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1syajk/eli5_how_do_dog_food_makers_know_if_their_food/ | {
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"text": [
"Actually, there are people that do taste dog food. I've seen an episode of dirty jobs. [Here's a women that does it for a living](_URL_0_)",
"They get a dog to taste it. The dog who works for pedigree barks once for good and twice for bad. Three barks means it needs more salt."
]
} | [] | [] | [
[
"http://www.nydailynews.com/life-style/eats/meet-woman-eats-dog-food-living-article-1.1445406"
],
[]
] |
||
6ac8eo | why is the integral sign on violins? | What is the shared history that makes the integral sign appear on musical instruments and in mathematics? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6ac8eo/eli5why_is_the_integral_sign_on_violins/ | {
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"It's a [sound hole](_URL_0_), specifically one shaped like the letter f. It's meant to help the instrument project its sound.\n\nThe integral symbol comes from the [long S](_URL_1_) which is similar to the letter f, but unrelated. The s here stands for \"sum\", since the integral is a form of summation.",
"Actually, no relationship. I'm sorry.\n\nThe sound hole in the violin, called an [F-hole](_URL_0_) is f shaped, but sometimes they don't carve the -. And the integral sign is the old form of a long s character, frequently used in the time of Leibniz (the guy that invented that notation, he chose s for integral because it's a sum).",
"The \"f\" hole isn't a cultural artifact. It's an amplifier.\n\nThe sound we hear is air that is compressed. A vibrating violin string compresses the air around it in a pattern our ears interpret as a musical tone.\n\nBut that string, by itself, doesn't vibrate a LOT of air. It's pretty skinny. And it doesn't give much ENERGY to the air it compresses, either. So the sound won't travel far. If you bowed a violin string alone (or plucked a bare guitar string), nobody in a packed theater would hear your performance.\n\nAdd a wooden board just behind the string, however, and it will also vibrate with the sound. Depending on how big the board is, it will push more air harder, making a louder sound that carries farther.\n\nMake that wooden board an open box, and now there's a lot more volume of air that gets pushed. The sound is even easier to hear.\n\nA rectangular box isn't great, though. Some tones will sound fine, but higher and lower ones will be too thin or quiet. That's because the box is a simple shape that resonates (vibrates along with) a narrow band of frequencies. Give that box a more complex shape, so bits of it can resonate with the high notes as well as the low notes, and you've got a pretty good instrument. Centuries of trial and error led to the violin shape we all recognize as being fantastic for this. (And they found that different woods resonate better, different densities, different internal structures, etc.)\n\nWhy an open box, though? Why not cover it up, and have even MORE resonance and amplification? Like shouting \"echo!\" in a tunnel.\n\nThe problem is, the air INSIDE the box has to get out, to send the sound to the listener.\n\nDifferently-shaped holes are better or worse at doing the job. If the hole is too big, you might as well get rid of the top of the box entirely. If it is too small, you're muffling your sound.\n\nIf you start with a simple circular hole, like a guitar, that's not bad. But over the centuries people figured out that you can get an even better result if you close up the center of the circle. If you just cut out the perimeter of the circle, you preserve more of the echo energy, and still get that air pumping out to the audience.\n\nIf you split the circle into two \"C\" shapes, you can put one on either side of the strings, so the input isn't interfering with the output.\n\nRemember how we reshaped the box to resonate better with different tones? How about we fiddle (ha) with that C. Instead of a constant curve, let's have part be tight and part be long, to maximize the wavelengths we can project.\n\nAnd that's how you get an \"f\" curve.\n\nAnd now even the people in the cheap seats far far away can hear the music of that tiny thin string vibrating next to a tiny wooden box.\n\nThe fact that math came up with a similar-looking long \"S\" symbol for the integral \"sum\" is pure coincidence."
]
} | [] | [] | [
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"https://en.wikipedia.org/wiki/Sound_hole",
"https://en.wikipedia.org/wiki/Long_s"
],
[
"https://de.wikipedia.org/wiki/Schallloch#/media/File:F-hole.jpg"
],
[]
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|
3nrg3o | why are most (if not all) shootings performed by guys? | Like, are us guys really THAT much more violent that girls? Why is that? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3nrg3o/eli5_why_are_most_if_not_all_shootings_performed/ | {
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"Not going to attempt to answer the question - sorry about that - but there has been at least one instance of a female shooter...[Brenda Ann Spencer](_URL_1_) who famously [didn't like Mondays](_URL_0_).",
"You may want to cross post this to /r/asksocialscience and/or /r/askscience with a tag for psychology to get a more indepth professional type answer instead of the more likely arm chair psychiatrist answer from here."
]
} | [] | [] | [
[
"https://en.wikipedia.org/wiki/I_Don't_Like_Mondays",
"https://en.wikipedia.org/wiki/Cleveland_Elementary_School_shooting_%28San_Diego%29"
],
[]
] |
|
5t5byy | the decline of the heavyweight boxer. | Ali. Frazier. Lewis. The heavyweight class was the pinnacle of boxing for a long stretch of the 20th century. What happened? Is there any truth to the idea that this weight class was a peer (in terms of popularity) of the MLB? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5t5byy/eli5_the_decline_of_the_heavyweight_boxer/ | {
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"Certain sports were much more popular in the no mass media and then radio era - horse racing and boxing are perhaps the two most prominent. But there is just a lot more options - NBA, NHL, NFL - the big team sports that more people play are more popular. \n\nWe don't ride horses as much. And we don't box a lot now. Plus there is the cruelty / harm aspects of it. Also, boxing got taken over by certain promoters and developed a very seedy reputation on corrupt arrangements of fights and wiffs of mafia influence, and then the big matches moved to pay-per-view, which, although profitable, limits them. ",
"In the early 20th century, America's Big 4 was MLB, Boxing, horse racing, and College Football. While horse racing declined, and other leagues like the NFL, NBA, and NHL gained prominence, boxing was still able to hold on for a long time. Boxing's ultimate issue was complete dysfunction in its organizational structure. There is no central governing body. There's a bunch of different federations that assign \"world title\" belts who's primary interest is getting a cut from the fight proceeds. You have an increasing inability to get the best fighters in the ring together if their promoters don't have a working relationship. Finally, the knock out punch so to speak was the move to pay-per-view. In the short term, it was a great movement for the individual fighters, as it increased their revenue. In the long term ignore killed the growth of the sport. An Ali-Frazier fight would be on a broadcast network network, get ratings on par with a World Series or NBA Finals, and expose millions of younger people to boxing creating life long fans. A Mayweather fight today can't do that, because pay-per view keeps the audience in the 7 figure range.",
"It is true that in the US, boxing used to be as popular as the NFL or MLB.\n\nThe problem with boxing is that people liked the sport, but they didn't like the process. Baseball has a very set process of determining the championship. Every team follows the same process and has the same shot to win it all. Win a pennant, win the divisional, win the World Series, and your are the champs.\n\nWith boxing, fighters, not a league, choose who they fight. A lot of it comes down to promoters manipulating who fights whom. You take a promising newcomer, line him up against a bunch of tomato cans, then tout his impressive 14-0 records to line him up for a title bout. At the same time, you have champions ducking serious fights an doing the absolute minimum they can get away with and still keep their titles. It is never clear who is the best fighter, and who gamed the system."
]
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9ni0fy | how do companies that seem to have a monopoly in their space (google, collegeboard, just to name a few) circumvent anti-trust laws? | Does the government just let it slide? Are the companies doing something shady? Does a company being "non-profit" change anything?
EDIT: TIL what antitrust laws really are! Thanks, guys! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9ni0fy/eli5_how_do_companies_that_seem_to_have_a/ | {
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"Well, first of all, governments don't let it slide forever. For example: _URL_0_\n\nBut more importantly, just being a monopoly is not inherently illegal. What's illegal is using your position as a monopoly to stop others from competing with you, or making conditions unreasonably bad for customers. For example, in the big anti-trust case against Microsoft back in the day, they weren't prosecuted because Windows didn't have any reasonable competition. They were prosecuted because they forced all Windows users to use Internet Explorer by default (making it hard to switch), so nobody could compete with Internet Explorer.\n\nSo for anti-trust laws to really apply, the government has to prove the company was abusing its monopoly position."
]
} | [] | [] | [
[
"https://www.theverge.com/2018/7/18/17580694/google-android-eu-fine-antitrust"
]
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|
3iygra | commercial intelligence vs industrial espionage | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3iygra/eli5_commercial_intelligence_vs_industrial/ | {
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"Commercial intelligence is a process whereby you purchase competitors goods, carefully examine any of their publicly available materials (marketing info, patent applications, sales trends and the like) to try to figure out what your competition is up to. So you can stay one step ahead, or at least not fall behind.\n\nIndustrial espionage is when you get that information illegally. Basically you get confidential information that you should not have access to and use that for a competitive advantage. "
]
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[]
] |
||
3g7oxk | why don't white americans rise up against police brutality like black communities do? | It seems like black communities seem to be able to respond in massive ways to police brutality. And while the majority of black murders at the hand of police go unnoticed, it seems like almost no white murders are noticed. I know the media has a role but the media usually comes up AFTER black folks have taken some sort of action. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3g7oxk/eli5_why_dont_white_americans_rise_up_against/ | {
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"In my community there's been police brutality on every race ever since I can remember. Honestly it seems like it happens so sporadically that we get angry but \"rising up\" doesn't really seem like it has ever solved anything. And in most cases it's their word verses the victim. This isn't an explanation, it is only how it seems to me.",
"It's hard to rise up against when it is so rare. There are perhaps a few dozen incidents per year and 350M people in the US. The chance of knowing the police departments involved is pretty low.",
"My town has not experienced police brutality. We did experience some corruption where the police were skimming from tickets and taking fees to not arrest meth makers. We fired the entire police force and then hired new ones. ",
"I think it's partly because we know that there isn't an onslaught of brutality that the media propagates. To really understand why officers act the way they do you have to understand what they see day in and day out. Recently on coontown a female corrections officer was explaining why she quit, in her post she told of how everyday the black community would masterbate in their cells as she walked past saying what they would do to her ect, she said she understood that the worst of all races were the ones in jail, but the nonblack inmates would never act in such a degradation way. So they have drawn the conclusion you have to be extra cautious around them. And statistically speaking blacks commit crimes more frequently than asians, indians, native Americans, whites, Arabs ect, and being a police officer you have the chance of being killed daily. They know how certain communitit's tend to act and are more cautious and alert, and possibly on edge when they think their life is in danger. To get back on track, the white community doesn't have this stigma, there are about 260,000,000 whites and of that population I think it's about 20% are arrested for violent crimes while blacks are the 12% of almost 400,000,000 and are convicted in somewhere around 52% of the violent crimes. So you are more likely to run into a violent black person than a white black person. Bottom line the black community is feeling the force of the law a drastically higher rates because they tend to have more negative confrontations with authority. White culture tends to look down on criminals and shunned them and feel \"that's what they get\" mentality for breaking the law. Not being black I can't honestly say how they view criminals, but based off the music and culture they propagate for everyone else to view it seems they aren't as harsh on law breakers within their own community. \n\nNot trying to trigger anyone, I understand their are possible billions of different opinions because we are all different, this is just one guys belief",
"It doesn't fit the current narrative of the national media. Popular news subjects are like fads, the news stations cover the current \"fad\" and when something new is trending, they move to cover those stories. Remember when Caylee Anthony was missing, missing children were covered nationally on a daily basis. The narrative is currently white cops/security vs. blacks and that will be covered until there is a new story that gets as much attention as Trayvon Martin's got.",
"Strong majorities of black people distrust the police and consider them to be more like oppressors and less like public servants.\n\nA narrow majority of white people support the police in this country and think they generally do a good job. Sizable portions of whites (not sure if it's a majority or minority) also think racism has been pretty much solved and don't think the police are racist at all. ",
"Simply, lots of tension between blacks and whites in America dating back 300+ years, and appropriately, blacks acknowledge that shit (um, it's a huge part of history and peoples' ancestry) while whites tend to think, \"Oh, it's 2015, there's no more racism because I'm not racist.\" This mentality only adds fuel to the burning fire.",
"They do, you just don't hear about it on the news because it doesn't fit their agenda. I've been to numerous police brutality protests where the majority of the crowd was white. ",
"Because, for the most part, it isn't a huge threat to the majority of the white population? They'd go to civil war if they were the majority targets."
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42pcjo | why do some people find it easier to study and remember things very late at night? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/42pcjo/eli5_why_do_some_people_find_it_easier_to_study/ | {
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"It's mainly to do with stress. The feeling that you've got to work with no time to spare for the next day really drives some people",
"Remembering, no. People find it easier to study because there are fewer distractions and also the deadline they are studying for is getting closer.",
"I am going to explain this as best I can, and someone else can correct me on the specifics if needed.\n\nBasically: Throughout out the day, you take in a huge amount of information. You hear stuff, you read stuff, you see stuff. Some of it you dismiss immediately. The things you want to remember go into short-term memory. Throughout the day you can call upon things that have been put in short-term memory. However, if you \"put something into\" short-term memory on Monday, and take a test on Friday, you can't pull upon the info. It has gone away. It was only stored \"short-term\". You can only remember what has been stored in \"long-term\" memory (and that day's short-term memory).\n\nStuff is put in long term memory during sleep. That's how it works. When you sleep, your brain says, \"Ok, that calculus formula seems important, I'll put that in this area labeled: long-term memory. Hmmm... I don't need to remember what color shirt my teacher was wearing today, that info goes in the trash.\" Next day, you remember the calculus formula, not the color of your teacher's shirt.\n\nNow, at night the brain sorts through the short-term memory and puts what is important in long-term. But it CAN NOT move things around that aren't there. Something put in short-term memory at the beginning of the day might have already left your brain before you go to sleep (because it was in low grade, faulty, temporary, short-term memory). Short-term memory carries info to long-term memory. So the later you take in info, the less time it has to escape before being locked in.\n\nTL:DR Late at night = closer to sleep. Sleep = long-term memory. \n \n\n\n"
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||
7k5pjk | how are few companies able to own majority of the brands i use? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7k5pjk/eli5_how_are_few_companies_able_to_own_majority/ | {
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"this is end game capitalism. lets say you have 100 companies all in one area. some do well, some don't. the ones that do well might buy out the smaller ones or the smaller ones go out of business. eventually once they become big enough, they start buying other smaller companies that retain their brand, since customers have brand loyalty. eventually after a while, you'll get what you described. "
]
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||
52frb2 | how was the numerical order decided? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/52frb2/eli5_how_was_the_numerical_order_decided/ | {
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"text": [
"Numbers have always existed, even before are species was aware of it. Once humans discovered what 1 of something was, they needed a name for all these numbers. "
]
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||
l7d8j | near field communication (nfc) | Ok, make this "Explain me like I'm a 9 year old geek that loves to build robots with legos and can dissasemble a clock and hopefully reassemble it back".
So every new android has it, iPhone 4S doesn't and it's supposedly a big thing. NFC or "Near field communication" and supposedly allows you to pay stuff with your phone, like a virtual wallet.
Why is this new and why does it require new hardware? Why can't you do the same with stuff in any smartphone, like wifi, bluetooth, the camera but new software? What's special about this radio chip that can't be done with the many other ways that computers communicate with each other? Bitcoin, paypal or credit cards are used to pay online without any new chip needed. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/l7d8j/eli5_near_field_communication_nfc/ | {
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"You know what infrared is? Well basically infrared is just a light which we can't see blinking on and off. There are two real types of modern NFC one which involves radio waves and another which involves magnets. They both work in a similar way. You know what a sine wave is? [The curvy one](_URL_0_). Well, the height of the sine wave is *AMPLITUDE*. Information can also be sent in sine waves and by a process of *MODULATION* you get a new sine wave. Modulation is basically adding one sine wave to another like [this](_URL_1_). This is known as *AMPLUITUDE MODULATION* or *AM* and is how some radios work. \nNow, another way NFC can work (magnetic only) is by simply turning on and off like infrared and is sort of like Morse code. \n \nSimple enough?\n\nReference: Former Electronics Engineering Student.",
"It's a very weak radio signal. So it only works when you are near (hey!) to it.\n\nAnd you need new hardware just in the same way that you need different hardware to hear things (your ears) and see things (your eyes).\n\nYour old phone doesn't have the right eyes to 'see' the NFC information. Just like a bicycle does not have any way to hear what you say. \n\nBitcoin, paypal, the reddit website, etc are more abstract concepts. \nThey are not about communication (like radio, wifi, bluetooth, your voice), but about handling information (like addition and making decisions).\n\nSo in short: NFC is a method of communication, not a computer program.",
"You know what infrared is? Well basically infrared is just a light which we can't see blinking on and off. There are two real types of modern NFC one which involves radio waves and another which involves magnets. They both work in a similar way. You know what a sine wave is? [The curvy one](_URL_0_). Well, the height of the sine wave is *AMPLITUDE*. Information can also be sent in sine waves and by a process of *MODULATION* you get a new sine wave. Modulation is basically adding one sine wave to another like [this](_URL_1_). This is known as *AMPLUITUDE MODULATION* or *AM* and is how some radios work. \nNow, another way NFC can work (magnetic only) is by simply turning on and off like infrared and is sort of like Morse code. \n \nSimple enough?\n\nReference: Former Electronics Engineering Student.",
"It's a very weak radio signal. So it only works when you are near (hey!) to it.\n\nAnd you need new hardware just in the same way that you need different hardware to hear things (your ears) and see things (your eyes).\n\nYour old phone doesn't have the right eyes to 'see' the NFC information. Just like a bicycle does not have any way to hear what you say. \n\nBitcoin, paypal, the reddit website, etc are more abstract concepts. \nThey are not about communication (like radio, wifi, bluetooth, your voice), but about handling information (like addition and making decisions).\n\nSo in short: NFC is a method of communication, not a computer program."
]
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f2xtx2 | they say my phone has more computing power than the computers that got apollo 11 to the moon. does that mean, theoretically, my iphone could orchestrate a moon landing from take off to touchdown? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/f2xtx2/eli5_they_say_my_phone_has_more_computing_power/ | {
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"Yes. You have more number calculating power than there's was on board at the time. They didn't need or able to have that much computer power. They weren't going to a random place that needed real-time calculations. Those were done months ahead of time on Earth and needed to be loaded in and the burn sequences executed by the computer. \n\nYour cell phone has 1000x capabilities of your high school TI-85 calculator. Which is already a complex computer.",
"With the right software that is true. In fact people have made simulators of the actual Apollo Guidance Computer which will allow your iPhone to not only orchestrate a moon landing but doing so by simulating the original computer. The statement is a bit outdated now. The updated statement is that your phone charger have more computing power then the computers that got Apollo 11 to the moon.",
"The computers that were used for the Apollo program had one task and one task only to land on the moon, the Iphone is running lots of things just to keep the phone operating and linked to the network, however given the right programming yes your phone could handle the processing of the information for a moon landing.",
"Yes and No.\n\nYes, your phone has plenty of arithmetic speed. You could definitely do all the multiplies, and then some.\n\nNo, your phone is full of gigantic blobs of code that keep it from performing like an AGC does. For the full story read Don Eyles memoir [Sunburst and Luminary](_URL_0_ ). Each instruction in those AGC programs was individually written by a smart engineer, and many hours were spent making them more compact and efficient. A custom interpreter was used when code didn't have to be perfectly fast. There is no practical way to run your own machine code on a smartphone, all the operating system software is built to prevent the kind of high performance computing done in early computers. Manufacturers care a lot more about enforcing license clauses than getting the right answer in the minimum number of instructions.",
"Yes, computing power of such device would only require few from few hundreds responsible for that landing at that time. Indian and polish universities did things like that (forgive me other countries but did not follow a topic for a while). Basically they connected with sources sending an ancual rocket to space and then separating and completening the landing of stuff like andruino board etc.",
"Theoretically your phone, or possibly [even just its charger](_URL_0_), would in theory be able to land something on the moon - your phone would be able to do it without even noticing the effort.\n\nHOWEVER, there are important differences and caveats;\n\nThe Apollo computers were specialised hardware with real-time operating systems - that means they were designed, built, and programmed in such a way that if you need to fire a rocket for EXACTLY 152 milliseconds, the computer can do that absolutely bang on every time even though it's a million times slower than your iPhone.\n\nYour iPhone, as it is out of the box with its non-realtime operating system, can TRY to do that, but because the OS doesn't guarantee that sort of real-time performance, you might fire the rocket for 152ms or, if at that exact moment an app decides to pop up and use a load of processing power, the rocket might stay on for a whole second... or if the app crashed the phone while the rocket was lit it might stay lit for 5 minutes while a little coloured whirly thing went round and you smashed into the moon at a thousand miles per hour.\n\nThis is the difference between operating systems like you find in your phone or laptop, and embedded systems that have to control real-world things that might hurt people or burn your toast.\n\nNow, *theoretically*, it's possible to create an OS like that for any system, but Apple like to lock their shit down so good luck with that one.\n\nThe various other *smaller* computers inside your phone (most of which are also capable of landing on the moon) which control things like the various sensors, the cellular radio, wifi, bluetooth, battery charging, etc. etc. etc. are more realtime and might be a reasonable prospect but are often somewhat single-purpose, so don't have enough IO (inputs and outputs) to do the job - in short, not enough legs on the chip to wire all the things to.",
"Yes your phone could. Just use google moon map and put in your location and then input where you want to land on the moon. You will be given directions to the moon. Then as you travel you can have your phone play Dark Side Of The Moon by\n Pink Floyd. You can have your phone order \nmoon pies through Amazon. You can google how to make moonshine and make your own moonshine.",
"I don't think there's anything compute heavy about sending something to space, orbit, or even another planet. Once the scientists figure out the maths it doesn't take a lot of computing power to actually solve the math problems and keep yourself going in the right direction. I'm not a rocket scientist but that seems like the simplest part of the equation by a long shot.",
"A modern smartphone can do 10 billion mathematical operations per second. The Apollo guidance computer did something like 32 mathematical operations per second.",
"Not only could your phone guide a rocket to the moon, it could also [simulate the rocket, the moon, and the Earth and draw a real-time 3D view of them](_URL_1_).\n\nIn fact, the math for orbital mechanics is surprisingly simple. Spacecraft basically fly in ovals around planets, and you can use [high-school geometry to chart a pretty accurate course](_URL_0_) that's good enough for most space missions. Space travel takes so long you could probably even do the math by hand.",
"A calculator from the 1980's is more powerful. Your iPhone is orders of magnitude more powerful than anything even conceivable in 1969. Yes, it could handle the moon landing.",
"That depends if it will be going in to space. A consumer device isn’t hardened for EM and other events that it isn’t exposed to at significant levels on earth but would be major risks in space. \n\nPart of the reason why on board computers from that era seem low powered was precisely so they could be hardened. This makes them far less prone to error or failure. Which is critical.",
"Even those electronic birthday cards that play a song when you open them have more processing power than the Apollo 11 ship... so yes",
"Not really. That statement means that in terms of pure computational power - literally how much maths can be done in a certain time, your iPhone can do more and do it faster. But keep in mind that you're asking one computer to do all the work by itself (well, usually 2 to 8, because it actually had multiple computers (processors) running at the same time.\n\nNASA used many many computers simultaneously to do different jobs, and each had its own processor that it didn't have to share. The computers each had a specific function to perform, and didn't have to wait to process the data.\n\nThere's no question your iPhone is more powerful than all those individual computers and even all of them combined. But there is the question is it able to process the data correctly. If your iPhone has a 4 processorvCPU and you need to execute 5 pieces of data simultaneously, you're out of luck. And maybe on your way to Mercury.\n\nThink of it this way: A Bugatti Chiron automobile generates 1,479 horsepower. This is more than 7 school buses combined. Does that mean it can get 400 kids to school every day?",
"Why doesn't every cell phone include [this](_URL_0_) then?",
"13 Minutes to the Moon is worth a listen. Apart from the typical computer stuff I was intrigued by things like how they learned to listen to several voices at once in their headphones.",
"Short answer: Yes. Your iPhone could do all the necessary calculations and could probably do them in a few seconds.\n\nLong answer: Probably not, no. Because this \"amazing fact\" usually relates to the actual Apollo Guidance Computer. You *could* replace the far bigger and faster computers on the ground that did all the mission calculations. Because that's just unspecific maths. As long as you get some numbers out, you're good. \nBut despite it being fairly \"modest\" even for its time, you *couldn't* replace the AGC. Because it's a **guidance** computer. It was built, from the ground up, specifically to control the CM and the LM. It did only that but it did it very, very well and very reliably. \nSo you'd have to find a way to get your phone to talk to all your space ship systems and do it reliably and quickly. I'm no computer engineer but I think the problem would actually be this interface. The necessary calculations would take almost no time at all, but \"translating\" all that input into something the iPhone could work with would either require software or a complex hardware adapter, in both cases, communications would take unacceptable amounts of time and be unreliable. \n\nBtw, a very extensive book about the AGC is available for download. I'm not entirely clear about the legality of the source (even though it's ESA), so I won't share it. But just google for \"apollo guidance computer architecture and operation\".",
"First of all you cannot judge the Apollo computers on a like to like basis. They were not entirely digital. On the Saturn V, there was a digital computer and an electronic [analog computer](_URL_2_) of about the same size. The analog computer did the differential equation calculations for flight control. The digital computer calculated times and values to feed the analog computer. Even Von Bruan's [V2(A4) was controlled](_URL_0_) by an electronic analog computer. (be sure to click on the top link on that page and scroll down to see diagrams of integrators and differentiators.)\n\nSecond, none of those computers has \"pretty pictures\". Meaning no graphical interface. They just input data, did a calculation, and output to a port for use. Graphical interfaces meant to look pretty to humans is the overwhelming calculation task of all modern computers. The GPU's are often far more complex than CPU's.\n\n[Here is a very good Youtube](_URL_1_) on the flight computer of the Saturn V launch vehicle. It is well worth watching all the way through.",
"not exactly, or at least, not precisely.\n\nConsumer grade cpu are not quite like the processors in a rocket. There's so much extra stuff to cheapen the system and speed up consumer applications that there's error in both the results and the timing.\n\nThis is not ideal for the computations done in a rocket, so more reliable systems are used.\n\nBut yes, your phone can technically have more \"computation power\" by the way of doing more things faster.",
"Yes and no. It has the computing power for sure, but it certainly lacks hardware requirements. Some of those are obvious (such as it's missing the Saturn V around it to fly there) while others might not be as obvious, such as having independent systems performing the same task to ensure redundancy. One thing to note about the computers running the Apolo program: They were not the most advanced, fastest or best computers available at the time. They were quite far behind on current tech, but they were known to be reliable, had actually been tested during space flight and were simple enough to be understood completely by a ground crew in case of an emergency, which saved both Apolo 12 and 13. The requirements were not \"get us the most computing power per kilogram\", they were more like \"Get us the most reliable stuff you can find for a voyage into the unknown\".",
"Definitely. Someone would need to wire up the inputs and outputs and either rewrite the Apollo 11 software or program an emulator. The Apollo capsule wasn't built with usb ports and the software wasn't written for iOS. :)\n\nThere could also be an issue with reliability. In space, cosmic rays can occasionally flip bits from '1' to '0' or vice versa. While I'm not sure if the Apollo missions used it, some computers used in space will take extra measures to guard against it that you wouldn't find in a smartphone. Smartphones are seldom subjected to intense radiation and it's unlikely that a glitch will result in a very expensive machine slamming into a planet.\n\nBut yeah, the U.S. and S.U. both would have killed for a smartphone.",
"It’s often forgotten that although computers weren’t as powerful as today, NASA didn’t want the most complex computers/systems aboard their rockets. More complicated computers just increases the risk of system failures, which obviously is not acceptable in a mission like landing humans on the moon.",
"Most of it could be done by hand with the right information and training. An iPhone is way more than capable of running the software as far as raw compute power goes. In fact you may be very well able to run the software in browser in an iPhone. You can do so on a PC.",
"Not just your iPhone.\n\nTo oversimplify things rather severely - to run any computer program successfully one needs a processor, (some) memory and (some) longer-term storage. This makes up the physical computer.\n\nRunning on those one needs an interpreter that tells the external hardware (The rocket itself) what to do with the commands it receives from the computer - for instance to stop the thrusters if the command [CUT ENGINE POWER] is received.\n\nThe 8088 which formed the basis for the IBM PC, released in 1981, just a decade after Apollo 11’s trip to the Moon, had eight times more memory than Apollo’s Guidance Computer (16k, vs the Apollo’s 2k). The IBM PC XT ran at a dizzying clock speed of 4.077MHz. That’s 0.004077 GHz. The Apollo’s Guidance Computer was a snail-like 1.024 MHz in comparison, and it’s external signaling was half that. \n\nTo the best of my knowledge, the guidance computers of the Apollo 11 carried two Kilobytes of RAM (That is half a MILLIONTH of a Gigabyte) and about 32 kilobytes of long-term storage - compare to a hard drive. You can fit that in a Gigabyte, thirty-one thousand, two-hundred and fifty times. \n\nSo - yes. Your iPhone is equipped with so much more processing power, so much more memory and so much more longer-term storage that the perspective is completely lost. \n\n[This watch, which can be bought as cheap as five dollars](_URL_0_) very probably has more raw _processing_ power than the onboard computers of the Apollo 11 mission had. It certainly has the processor speed to pull it off.\n\nThat statement is in itself not _quite_ true, however, in that you couldn't just swap out the mission computers for a modern cheap watch and watch the whole thing go off without a hitch. The watch is not setup by default to handle the 145 thousand lines of code that constituted the _programming_ for the Apollo 11 mission. \n\nIf you could get the watch to run the interpreter and talk to the memory and longer-term storage, _then_ you could probably wire it into the Apollo-11 rocket to replace the mission computers.\n\nYour average modern iPhone probably uses more computational power to display the on-screen clock than would have been required to run the Apollo-11 mission.",
"Lol - your iPhone would probably have enough charge to get to 500ft if my phone is anything to go by.",
"Technically yes, but what is missing from a lot of the responses I've seen on here, is that an iPhone wouldn't be a great choice for spacecraft. Long answer below.\n\n\nPeople underrate the Apollo Guidance Computer(AGC) simply because of raw processing power, it still does things that modern consumer computers do not.\n\nThe AGC was a specialised real-time, priority based computer. This basically means it had a multitude of small, very specific programs it could run, requested sequentially. As these programs could never do more than intended in tightly controlled and practiced scenarios, there was a degree of objective importance in the running of these programs. The AGC could defer less important tasks and most importantly, it could do it quickly and without contention. For it’s task, it was all that was needed and very efficient and incredibly reliable. Reliability is the most important factor in applications like this.\n\nModern Space hardware still use relatively modest computers. Curiosity, which is currently wandering around being brilliant on Mars, has two identical computers with, what most would consider, pretty crappy specs. It’s processors only run at couple of hundred MHz and it was launched in 2011. The processors is question are radiation hardened and there’s two of them to make the system less error-prone. Curiosity also uses a modern descendent (Kinda)of the AGC, a lightweight real-time OS called vxWorks. The specs aren't confirmed, but it’s likely that Mars 2020 won’t be magnitudes more powerful either.\n\nWe now have more computing power than we could ever possibly need for completing basic computing. This means we use computers to do far more nowadays, a side effect of that is inefficiency and more wasteful languages that allow is to achieve complex things quickly. Consumer computers crash, they fail. Not often catastrophically, but subtly far too often for critical applications. There's layers upon layers of processes for myriad things in the system.\n\nBy comparison, the AGC had no operating system. No central processor in the way we understand them, no RAM, no filesystem. It was a very different beast to a modern computer, but for it's application, it was great.\n\nThese systems above all, need to be reliable. Lower level languages that make better use of processing power and operating systems that favour quick decision making will always be preferable to an iPhone that can crunch (relatively) wasteful and imprecisely determined numbers faster. \n\nAll that being said, three iPhones would be great at getting us to the moon. Triply redundant systems can mitigate a lot of error prone nature of modern computing and mess ups caused by cosmic rays.",
"This analogy might help. The comparison that is made is regarding the power of the phone to the Apollo flight computer.\n\nThis is like saying could my Ford Focus car engine really power a Model T?\nSure it could. Could you just put a focus' engine in a model T with no other changes to the engine or model T. No."
]
} | [] | [] | [
[],
[],
[],
[
"https://smile.amazon.com/Sunburst-Luminary-Apollo-Don-Eyles-ebook/dp/B07L9YQ9WV"
],
[],
[
"https://www.extremetech.com/extreme/306119-your-phone-charger-is-probably-smarter-than-the-apollo-guidance-computer"
],
[],
[],
[],
[
"https://en.wikipedia.org/wiki/Patched_conic_approximation",
"https://www.youtube.com/watch?v=JYjsSLrY4U4"
],
[],
[],
[],
[],
[
"http://moonlander.seb.ly/"
],
[],
[],
[
"https://www.cdvandt.org/v2__computer.htm",
"https://www.youtube.com/watch?v=6mMK6iSZsAs",
"https://en.wikipedia.org/wiki/Analog_computer"
],
[],
[],
[],
[],
[],
[
"https://en.wikipedia.org/wiki/Casio_F-91W"
],
[],
[],
[]
] |
||
3oc32k | if isil/isis income is from conquered oil fields - why don't nato just bomb the oil terminals? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3oc32k/eli5_if_isilisis_income_is_from_conquered_oil/ | {
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"Not Just that but tankers heading to borders should be pretty obvious and relatively easy targets for drones to both see and eliminate ",
"That probably has to do with the fact that it is not generally acceptable to intentionally kill civilians. The UN would be very unhappy.",
"The petroleum industry isn't a local or regional entity and bombing oil fields will likely cause more geopolitical backlash from others. Plus, I'm sure it's possible to ruin reservoirs and trap hundreds of thousands of barrels of oil in the subsurface and/or cause some kind of environmental issue. Wasting/destroying a valuable natural resource like hydrocarbons isn't a wise decision, regardless of your stance on fossil fuel consumption. ",
"2 reasons:\n\n1) Some of the oil is being sold to big countries with big militaries, and they wouldn't be happy if it stopped. We're already trying to avoid this turning into a proxy war (where big players with deep pockets dump weapons into the region on opposite sides), so that wouldn't help.\n\n2) Part of the money is used for social services. ISIS is a crazy organization, but they win the people over by providing services that the local government doesn't. _URL_0_\n",
"First of all, [the US has been destroying oil fields and refineries to a large extent.](_URL_1_) Simply destroying everything would [harm recovery in a post-ISIS world though.](_URL_2_)\n\nAlso, oil isn't ISIS' only source of income, as they regularly [loot banks in captured areas.](_URL_0_)",
"The foreign policy of countries dealing with ISIS is treating it more like a child having a tantrum, rather than a formidable enemy playing to win. Think of how WW2 was fought versus wars of today. Cities were leveled. Why? Because we were just that close to losing. That we had to win and that means destroying anything the enemy could use.\n\nWe have very pragmatic altruistic foreign policy where we're more concerned with international feelings and our image than actually winning. ISIS could be eliminated in under a week, if we really want to end this. Destroying their means of financing, the electricity they use, the way they fuel their vehicles, the buildings they sleep in (we can just level towns). \n\nThe problem that you notice is that there is no sense of urgency or means to just win (ISIS is playing to win). It's more about measured responses and just slowing ISIS down."
]
} | [] | [] | [
[],
[],
[],
[
"http://www.theatlantic.com/international/archive/2014/06/the-isis-guide-to-building-an-islamic-state/372769/"
],
[
"http://www.ibtimes.co.uk/mosul-seized-jihadis-loot-429m-citys-central-bank-make-isis-worlds-richest-terror-force-1452190",
"http://www.bloomberg.com/bw/articles/2014-10-14/u-dot-s-dot-air-strikes-cut-isis-oil-production-by-70-percent",
"http://edition.cnn.com/2015/07/10/politics/donald-trump-fact-check-bomb-oil-fields-iraq/"
],
[]
] |
||
6p247l | how can animals eat other animals and not destroy their insides from the bone shards / teeth? | When I accidentally eat a salmon bone I feel it poking me and spit it out while it is still in my mouth!
I just saw a video of a killer whale eating a great white shark. I've touched a great white shark tooth before and it was incredibly sharp. How does the killer whale eat the shark without those teeth cutting its throat or stomach?
| explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6p247l/eli5_how_can_animals_eat_other_animals_and_not/ | {
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"dkm9cih"
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"text": [
"Some animals have specific enzymes that can break down bones, nails, and such hard materials. I think I remember reading somewhere that crocodiles can actually digest steel"
]
} | [] | [] | [
[]
] |
|
4b2l1n | why can the usa interfere with military actions outside of their territory? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4b2l1n/eli5_why_can_the_usa_interfere_with_military/ | {
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"We are a superpower. One of the aspects of being a superpower is that the entire planet is our territory so far as military actions are concerned. ",
"They have the \"right\" to do it. Good reason for using military force and permission from UN etc. \n\nThey can't \"invade\" another country, that has a sway in the UN. Usually eastern countries are not stable and can't say anything about it. You don't see US invading western countries like Russia did with Crimea (Which is kinda eastern too). One reason why Russia was able to do so, Ukraine is not in NATO. All EU and UN can about it is to economically sanction Russia.\n\nAll of this is what I have learned from news and such. Feel free to correct me if Im wrong"
]
} | [] | [] | [
[],
[]
] |
||
8i8gru | how does white reflect light and black absorb light? whats the process behind this? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8i8gru/eli5_how_does_white_reflect_light_and_black/ | {
"a_id": [
"dypq5b5"
],
"score": [
2
],
"text": [
"Our eyes interpret light with frequencies covering all visible colors as white and the absence of light as black. When you shine white light on a white object, it'll reflect all of it, and our eyes will interpret it as such. If you shine light on black object, none of it reflect back to our eyes, so our eyes interpret that absence as black.\n\nIf you are asking why some things reflect light and some things absorb it, it comes down to how the atoms of the material interact with light. When an atom is hit with a photon, depending on the frequency of that photon, the atom will absorb it (transparent materials will not absorb it, allowing it to pass through). This may give the atom enough energy such that it re-emits a photon of its own. Or it doesn't, and the photon is absorbed with no light shining back."
]
} | [] | [] | [
[]
] |
||
dumlzw | why can we not feel temperature differences of beverages consume navigating to stomach | Why when we consume a beverage that is extremely cold (e.g. ice water) or extremely hot (e.g. herbal tea) we cannot feel it going down our esophaguous and whilst navigating through our body though it is extremely cold in the mouth and on teeth, or if that liquid was poured on our skin we could feel the extreme cold / hot. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dumlzw/eli5_why_can_we_not_feel_temperature_differences/ | {
"a_id": [
"f774jqc",
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"text": [
"Because first of all that would be a stupid feature to have in the body because what purpose would it serve, and second of all, receptors for those things don't exist in the digestive system because, like I said, why would we have it",
"This post is confusing to me, because I definitely feel the temp if I drink something very cold or very hot!"
]
} | [] | [] | [
[],
[]
] |
|
24c5l3 | why is it easier to fall asleep "unintentionally" then when i'm trying? | I fall pretty easily a sleep when I'm laying down on the couch watching a movie, or just "chilling out" on the couch/bed, but when I actually go to sleep at night, I often take half an hour or more to fall asleep? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/24c5l3/eli5_why_is_it_easier_to_fall_asleep/ | {
"a_id": [
"ch5oht2"
],
"score": [
2
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"text": [
"When you naturally fall asleep, your brain and your body is probably tired enough to do so.\n\nWhen you're consciously trying to fall asleep, you focus your attention on the act of falling asleep, which makes you more aware that you are awake along with other thoughts that might pop up and get in the way. So you're really just thinking a whole lot. This is why the whole \"counting sheep\" technique exists - you're exerting very little brain power to think about something mundane and boring enough to have you drift off."
]
} | [] | [] | [
[]
] |
|
21ustb | how does a mental or personality disorder affect someone's ability to control their behavior? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/21ustb/eli5_how_does_a_mental_or_personality_disorder/ | {
"a_id": [
"cggrnoj"
],
"score": [
2
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"text": [
"This is a very broad question with different answers depending on the specific disorder being discussed, but broadly-speaking there are two different answers to your question. Certain disorders can cause certain types of hallucinations which convince sufferers to undertake certain actions or to refrain from certain actions, ultimately because they are under the impression that it is not reasonable to do otherwise. This is called, appropriately enough, a [hallucination](_URL_0_). And certain disorders can cause sufferers to be unaware of how their conditions is affecting them or influencing their behaviour, leading them to embrace reasoning which casts their behaviour/condition in a righteous point-of-view and reject notions of adopting a different behaviour. This is called a lack of [insight](_URL_1_)."
]
} | [] | [] | [
[
"http://en.wikipedia.org/wiki/Hallucination",
"http://en.wikipedia.org/wiki/Insight#Psychology"
]
] |
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