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3xdfyn | why have homework if they could just keep you into school for longer? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3xdfyn/eli5_why_have_homework_if_they_could_just_keep/ | {
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"Homework has the benefit of forcing you to perform practice questions on your own, without coaching from teachers (parents, this means you stay out, even if you are a qualified teacher thing person). Otherwise, you'd just get lectured more, and there are both diminishing returns and limitations on the efficacy of additional lecturing.\n\nELIashully5: you learn better on your own",
"Teacher here- \n\nThe basic framework of teaching a skill is this: Teacher led, group practice, then individual practice. This means you're gradually getting less and less support as you master the skill. Homework is the \"individual practice\" part- it's our way of letting you practice a skill or concept to reinforce it. "
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6q487n | are oilfields huge dinosaur graveyards? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6q487n/eli5_are_oilfields_huge_dinosaur_graveyards/ | {
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"Contrary to popular belief, most oil isn't actually from dinosaurs. The vast majority of oil was created from plankton and algae. There might be a few molecules of dinosaur but not much.",
"No, the majority of petroleum is made from the fossilised remains of plankton and algae, altered by immense heat and pressure along with an anoxic environment.",
"No. Oil is purely formed from sediments deposited in (generally quite deep) marine environments, largely from plankton (microscopic plants and animals that float in the oceans). A lot of oilfields were formed around the time that dinosaurs existed, but they themselves wouldn't make up any significant proportion of the organic material whatsoever. \n\nCoal is the only fossil fuel that forms in terrestrial (land) settings. Coal is primarily made from plant matter but it is conceivable that a very small proportion could be made from terrestrial animal remains. "
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1rldxy | what is the difference between psychopathy and aspd? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1rldxy/what_is_the_difference_between_psychopathy_and/ | {
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"Psychopathy is a term that the American psychiatrist Hervey Cleckley coined in 1976 that actually predates the DSM antisocial personality disorder. Hervey Cleckley's criteria for psychopathology, unlike the DSM diagnostic criteria for APD, refer more to the person's thoughts and feelings. Unlike APD, the criteria for psychopathy do not require onset of symptoms before the age of 15 like the DSM requires."
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74bsez | why is it that we put ice on some injuries (e.g. black eyes) but want heat on others (e.g. sprains)? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/74bsez/eli5_why_is_it_that_we_put_ice_on_some_injuries/ | {
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"Because ice is used to reduce swelling while heat is used to bring more blood to the area. Bone injuries and muscle injuries also benefit from the different applications.",
"Yeah for sprains you're still going to want to use ice. For muscle strains heat can be used, but mostly you can't go wrong using ice on an injury."
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nvphq | what's the appeal of blonde hair? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/nvphq/eli5_whats_the_appeal_of_blonde_hair/ | {
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"My guess is that its rarer than other colors so people tend to value it. Just like with precious metals and things like that. ",
"Because it's \"different\".\n\nI'm a blonde dude and when i went to China I got a ton of stares.",
"Not really like you're five but:\n\n > The genetic mutation that's linked to blond hair only popped up about 11,000 years ago, spreading from modern-day Lithuania out across Scandinavia and the rest of northern Europe rapidly.\n\n > There are a couple of competing theories about why this happened. Some scientists believe that lighter hair, like lighter skin, allows for more effective vitamin D manufacturing, which was extremely important for maintaining health in the chilly, dark northern Europe of the last Ice Age.\n\n > The other school of thought holds that blondes evolved simply because the color was novel and interesting, so in a time when there were very few men compared to women, men were more likely to select blond mates, leading blond women to reproduce much more often.\n\nfrom [The History of Blond Hair](_URL_0_)",
"Boys will, without knowing, look for signs of health in girls (if they aren't yet afraid of cooties).\n\nHealthy hair is a really big indicator of a girl's age and boys have used this to quickly tell a girl's age for many years, as boys typically prefer girls in their 20s rather than their 60s. It's easy to tell if a girl has a lot of grey hair but bright blonde hair is a good sign of more youth than dulled brownish blonde hair. (Actually, most of the appeal from guys for blonde hair is for bright vibrant healthy looking blonde hair, not dulled blonde hair.)\n\nThe same actually applies for shiny well kept hair and messy dry looking 'dead' hair.\n\nOf course, all of this stuff is easy to fake in the modern days, but that's what boys have had to work with for many many years. Also, personal preferences always beat out general preferences. Some boys will just like girls with one type of hair due to experience or culture or such. Some boys will also like dull blonde hair. People are awesome like that, with their different tastes.",
"My guess is that its rarer than other colors so people tend to value it. Just like with precious metals and things like that. ",
"Because it's \"different\".\n\nI'm a blonde dude and when i went to China I got a ton of stares.",
"Not really like you're five but:\n\n > The genetic mutation that's linked to blond hair only popped up about 11,000 years ago, spreading from modern-day Lithuania out across Scandinavia and the rest of northern Europe rapidly.\n\n > There are a couple of competing theories about why this happened. Some scientists believe that lighter hair, like lighter skin, allows for more effective vitamin D manufacturing, which was extremely important for maintaining health in the chilly, dark northern Europe of the last Ice Age.\n\n > The other school of thought holds that blondes evolved simply because the color was novel and interesting, so in a time when there were very few men compared to women, men were more likely to select blond mates, leading blond women to reproduce much more often.\n\nfrom [The History of Blond Hair](_URL_0_)",
"Boys will, without knowing, look for signs of health in girls (if they aren't yet afraid of cooties).\n\nHealthy hair is a really big indicator of a girl's age and boys have used this to quickly tell a girl's age for many years, as boys typically prefer girls in their 20s rather than their 60s. It's easy to tell if a girl has a lot of grey hair but bright blonde hair is a good sign of more youth than dulled brownish blonde hair. (Actually, most of the appeal from guys for blonde hair is for bright vibrant healthy looking blonde hair, not dulled blonde hair.)\n\nThe same actually applies for shiny well kept hair and messy dry looking 'dead' hair.\n\nOf course, all of this stuff is easy to fake in the modern days, but that's what boys have had to work with for many many years. Also, personal preferences always beat out general preferences. Some boys will just like girls with one type of hair due to experience or culture or such. Some boys will also like dull blonde hair. People are awesome like that, with their different tastes."
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47odm5 | why are some movies on torrent sites before they actually release the dvd/bluray? | No, I'm not talking about going with a camera and filming the movie. I'm talking about actual DVD releases, movies like "The Revenant", "The Big Short" and I think that "The Hateful Eight" is also on torrents but i'm not quite sure about that. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/47odm5/eli5_why_are_some_movies_on_torrent_sites_before/ | {
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"They were leaked copies. They were probably obtained by hackers, or someone who works for the company somehow released it on accident. ",
"I know that one of the biggest music pirates in history worked at the plant that burned and distributed CDs. Since CDs sometimes have to be shipped to retailers weeks before their release date, he would take a copy home and upload it on the Internet well before release. \n\nI assume movies get uploaded in the same manner. ",
"Leaked copies, screeners intended for the judges of awards shows, and more recently, more movies are being released digitally slightly ahead of physical dvd or blurays, so illegal copies of those hit right away."
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873sf9 | if moon is visible during daytime, why does it affect tides during night? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/873sf9/eli5_if_moon_is_visible_during_daytime_why_does/ | {
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"The moon's gravity is what causes tides (so, its position), regardless of when we can see it.\n\nThe moon takes about 28 days to go around its orbit-- its position in its orbit dictates how visible it is to us. If it's closer to the sun, we can only see it as a shadow. If it's away from the sun, it's a full moon. Meanwhile, the Earth will rotate 28 times. The sides of the earth that faces the moon (or on the opposite side of the earth from the moon) are the places that get high tide.\n\nThe oceans that are close to the moon get pulled towards the moon. This kind of pinches the water that is neither close nor far from the moon, and to balance it out, the oceans on the opposite side from the moon then also get high tide."
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36cuvn | what are the primary limiting factors on the size of submarines? | It seem's like whilst most submarines throughout history have been fairly small, that there have been some exceptions that break the rules (_URL_0_). So I was wondering, are submarines like this simply not built any more because it's not worth it? Or is it because of other problems caused by their size? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/36cuvn/eli5_what_are_the_primary_limiting_factors_on_the/ | {
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"A larger submarine creates a larger surface area that makes it more vulnerable to pressure, as well as increasing the time it takes to fully submerge / surface. Since submarines are rarely for commercial usage there really is no incentive to go a lot bigger.",
"1. Size does not scale well with the strength of the construction.\n2.Bigger subs require bigger engines. Bigger engines = more noise. You do not want to be detected if you are on a sub.\n3. There is a trade off between size and its detectability. The bigger it is, the more chance that it gets detected. Nuclear submarines are designed to deliver nukes as close to the enemy as possible. A small amount of nukes is enough to fuck your enemy up, so a smaller sub can do the job. You can of course make it huge and make it carry a shitload of nukes, but what is the point if you get detected and blown up.\n4. Maneuvrability is a large factor. The bigger you are the slower you are. The point of a sub is to descreetly deliver a nuke and get the hell out of there. If it takes you a day to make a U-turn, you just aren't gonna make it.",
"Larger things more expensive, harder to build and maintain, easier to detect\n\nWhen you already carry a hundred mirv warheads that can destroy any country, do you really need to go even bigger?"
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1u5sts | would it be legal for someone to build a spaceship in their backyard and fly to the moon? | Assuming they didn't break any laws obtaining illegal materials. What would happen if someone tried this? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1u5sts/eli5_would_it_be_legal_for_someone_to_build_a/ | {
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"I think they would need to notify air traffic so they don't interfere with other airborne objects while traveling because that could be dangerous. ",
"Yes, it would be perfectly legal. The necessary permissions would need to be obtained from air traffic control, but really not that difficult to get permission to do it.",
"You would never be able to get the building permits from your town (assuming your town demands these stupid things) Plus if you had neighbors close you are now a fire hazard. Good luck though!",
"Nope. Because at some point you'd need to get the fuel. It'd be impossible to get the explosive permits for your backyard",
"There was a [TV series back in 1979](_URL_0_) about a guy who does this.... it was called \"Salvage-1\". The scientific advisor was none other than Isaac Asimov.",
"It may well be illegal, but once you're on your way I really don't see how they'd be able to stop you.",
"In the United States, the FAA has sole regulatory authority over suborbital spacecraft. IIRC, you need to request a permit, probably do a shitload of paperwork, then when your ready they will issue you a temporary flight restriction (TFR) over your launch site so no air traffic can transit the area for an allotted amount of time.\n\n_URL_0_",
"This has been done. Not necessarily in their backyard but on land they owned. There is an obvious risk of launching a rocket next to houses and such. There are several things to be considered though. \n\nAssume you don't need any permits to build this rather massive craft. One issue that comes up is the fuel. When others have tried this, the FBI was rather unhappy with the person obtaining the fuel then trying to create it themselves. Assuming you can get the proper permits to create the fuel then the permit to use it. Hurdle 2 is going to be getting the FAA off your back about getting a flight plan and return plan approved. Something they aren't likely to do without a lot of convincing. You will also need to likely convince local and state police of your intentions along with the state department and DoD that you aren't building a missile. \n\nIt's not impossible but it's improbable that you would get it done in the US. ",
"In addition to the explosive materials permit, and the FAA waiver; you'd need to get the proper radio licensing. The other problem is that one person couldn't possibly do this entire endeavor on their own. Even if you were able to launch and never come back to earth, the people that helped you would be held accountable. (ie...fined, jail time)\n\nThe closest thing you could do is build a rocket then take it into international waters to launch. Which is basically what the folks at Copenhagen Suborbitals is doing.",
"In their backyard, no. Too many explosive materials. However, if launched at an appropriate site, it could be approved, but it would take a lot of paperwork. [These guys](_URL_0_) are attempting to put a man in space and are based in Denmark. ",
"The quantities of jet fuel alone would put you on some watchlists.",
"It would be a violation of the Outer Space Treaty (_URL_0_)\n\nThe Treaty limits activities beyond Earth's atmosphere exclusively to states, not individuals. Article VI says: \"The activities of non-governmental entities in outer space, including the moon and other celestial bodies, shall require authorization and continuing supervision by the appropriate State Party to the Treaty.\"",
"Fueling it will be your biggest problem. \n\nIf you're going to use fuel like the space shuttle does, you're going to need some really nasty stuff (ammonium perchlorate, hydrazine, etc) which will require far more regulatory hurdles than actually flying.\n\nUnless you manage to invent a new rocket that uses unregulated components.",
"Astronaut Farmer\n\n_URL_1_\n\nbut then this would happen\n_URL_2_\n\nand finally this\n\n_URL_0_\n",
"Even if you did you would kill anything living nearby.",
"of course not. you think those mother fuckers are gonna let you blast off into space? ",
"As long as you remember to take your passport"
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1q06v5 | how are close elections called so definitively with such a low % of precincts reporting? | I come across this every election to some degree (and it probably comes up in ELI5, but I couldn't find it in search): I'm currently watching the news, where one of my local races is pitting two candidates against each other.
As of now, Candidate A currently leads over Candidate B, 51%-49%, with only 67% percent of precincts having reported in... but the race is already being called for Candidate A. It's a local race, both candidates are from the same party, and as far as I've been following, polls have showed them being pretty even.
What's going on here? I understand that networks want to be first to call something; but how can a race that is so close -- and so variable -- be called with so early, and with so little information? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1q06v5/eli5_how_are_close_elections_called_so/ | {
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"Having asked this before myself, it's the [Law of Large Numbers](_URL_0_).",
"Because we have statistical tools that are pretty reliable predictors of such things.\n\nIn your example, in order to win a 51%-49% election with 67% counted, the remainder would have to go 52%-48% in the other direction. They can take the delta from the latest polls and the actual results with the counted precincts, and use that delta with the last poll results in the uncounted districts to get a pretty accurate projection.",
"Political science and the numbers associated with it are studied VERY carefully. And they know a lot more about the returns than just the percentages that have reported that is all factored into the decision to call an election. \n\nOne big issue is which precincts have reported. On a state wide basis, you are likely to have certain areas that have heavy support for one candidate or the other. Certain precincts may also have far more votes than others. So even if the race seems tight in the 67% percent that have reported their results, if they can look at the remaining areas and know that one area is likely to return a large amount of support for candidate A, and the areas with the strongest support for candidate B have already reported, they can assume that candidate A will get most of what is still coming in to claim the victory.\n\nEven without final results, you can get a good sense of the results of an election with exit polling. And if you can take your exit polling for the 67% that have finalized the results and confirm that your polling was accurate, you can then have that much more confidence in the exit polling you have done in the remaining 33% of precincts. \n\nTL;DR version: the simplified numbers you see look close. The people who are actually \"calling\" the race are looking at mountains of carefully researched numbers to make that prediction."
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47c5tk | why are there no laws against drinking and smoking while pregnant? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/47c5tk/eli5_why_are_there_no_laws_against_drinking_and/ | {
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"There's multiple problems. For one, many people would find that an unacceptable intrusion of the government into your life--adults must generally be assumed to make competent decisions for themselves. This means you must occasionally let them stray into poor decisions. \n\nA law of this nature would also deal in absolutes, with little consideration for reality--drinking a glass of champagne on New Year's Eve is mostly (though not totally) harmless, so why should we file that woman under the same category as an alcoholic or chain smoker? There are few good legal tools for distinguishing the two.\n\nThird, consider how hard it would be to enforce. Most drinking or smoking is done inside the home--you might prevent a woman from purchasing liquor or tobacco, but that surely won't prevent her from obtaining it through other means. Or are we to interrogate male purchasers whether they are not secretly purchasing for their pregnant wives, sisters and mothers? Prohibiting the consumption of any drug in the home setting is rarely very effective, which is why in some states, it is even legal for parents to provide alcohol to their minor children.\n\nIt also helps that we already have broader, more considerate laws in place. It is generally accepted that sometimes the state must intervene in cases where parents neglect or abuse their child. Alcohol or tobacco abuse, including during pregnancy, could be a factor in a judge's decision when an allegedly unfit parent comes before the court. That is a much better setting for evaluating the actual impact on a child.",
" Laws designed to protect a fetus come into conflict with the principle that a woman owns her own body. Obviously there is a conflict between these goals, and the law must settle the conflict. If you assume the fetus has rights, then there is no perfect answer. ",
"Drinking is actually not harmful to the fetus in moderate amounts. It becomes an issue with alcoholism and massive intake. We've convinced women that there kid will be screwed if they have a single drink. ",
"[Here is a good article on such laws](_URL_0_).\n\n1) Research on the ill-affects of a pregnant woman's actions are not as conclusive as one might expect.\n\n2) It would be a huge invasion of privacy. Would the police troll the bars looking for fertile women? \n\n3) The only place where pregnant would conceivably be \"caught\" admitting to unhealthy behavior is in the doctor's office. And we want to ENCOURAGE pregnant women to be visiting the doctor, not discouraging their honesty about their health.",
"Laws against this would conflict with Roe v. Wade. \n\nThink about it this way: how could you outlaw pregnant drinking (which is terrible for a fetus) when it would be illegal to kill/vaccum out that same fetus? "
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1xadfh | after years of persecution and prosecution, why is marijuana suddenly ok now? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1xadfh/eli5after_years_of_persecution_and_prosecution/ | {
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"It's actually still illegal at the federal level and 48 of the 50 states (medical not included).\n\nThis sounds like a really loaded question. If you want an answer to the legitimate parts of your question, re-ask them to the search bar."
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5g9vng | the first computers were mechanical, bulky and relatively simple. how do you jump from that to operating systems, light-up screens, programs and cursors? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5g9vng/eli5the_first_computers_were_mechanical_bulky_and/ | {
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"You don't \"jump\" from one to the other. You do it in tiny steps.\n\nAfter mechanical computers, you move to electrical computers. They're still bulky. They take their input in the form of punched cards. They may have a handful of lights on the front for output, or they may produce punched cards as output.\n\nThen, you increase the number of lights that you use for output. And once you've got enough lights, you can arrange those lights into a pattern that allows the computer to truly display a few letters or even a few words.\n\nNext, you move on to having a screen for the output, although it can still only display text. But from there, it's not a massive leap to have computers that can display graphics.\n\nAnd by the time graphical computers are common, computers are already powerful enough that they can handle windows, icons, menus, pointers, etc, quite easily. Moving to a world where every computer comes with a mouse to drive that pointer is more of a marketing challenge than a computing one.",
"It really depends on how you define a computer, but by most definition they were never \"mechanical\". That's a bit of the point of an electronic computer. \n\nAnd they didn't change overnight. We're talking decades here. You start with a device where you flip switches and lights come on in response. Then you add more sophisticated switches and lights. Then you go \"Hey, we already have TVs, that's just a sophisticated light, really\" and you make a system that outputs a signal that a TV can display. \n\nAnd then you make a keyboard (which is just a bunch of switches).\n\nAnd then you go \"Hey, these vacuum tubes are huge and bulky and get really hot, let's get something better\" and someone invents a transistor. And then someone makes it *smaller*. And then someone puts a whole bunch of them in a single package, and continues to make it smaller. \n\nAnd someone makes that signal that goes out to the TV be able to produce different colours (because someone invented a colour television so why not). \n\nAt this point people are noticing that computers are kind of useful, and some big companies are making them, and there's an incentive to innovate and improve, and a whole bunch of really smart engineers are working on this, and a whole bunch of them build upon what the others are working on. \n\nAgain, we've had 70+ years of progress in this industry. ",
"The single biggest leap was the move from vacuum tubes to transistors. Both can be thought of as electric switches. Their purpose is to act as switches that not only control the flow of electricity, but are themselves switched on and off with electricity.\n\nA vacuum tube is often roughly the size of your thumb. The transistor came about when people discovered they can accomplish the same effect by layering substances with different electrical properties right on top of each other. This took the size of the switches from the size of a finger to the size of a fingernail. As they developed better manufacturing techniques, they were able to make these transistors smaller and smaller.\n\nThen came the integrated circuit, the single most influential technological innovation of the 20th century. Instead of connecting transistors with copper wires, now they can build tiny circuits by layering silicon with various impurities mixed in to alter its electrical properties.\n\nSource: recent electrical engineering graduate."
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fbquc8 | drug tests seem backward. | Why are breathalyzers used to test something you drink and a urinalysis used to test something you inhale? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fbquc8/eli5_drug_tests_seem_backward/ | {
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"Alcohol goes into the blood. The blood goes into the lungs. The alcohol “evaporates” into the air in the lungs that you then breath out. We can measure this and using a ratio we can determine how drunk you are. \n\nTHC is inhaled into the lungs. From the lungs it goes to your blood. The metabolites (left overs) of THC are stored in your fat, seep into your blood over time and comes out through your urine as your body “cleans” your blood. We can detect these THC leftovers in your urine. \n\nThis is as ELI5 as one can get without going into technicalities.",
"1. In terms of drug class, Alcohol could be referred to as a *volatile solvent*. This group would include Propane, Butane, Diethyl Ether, gasoline and numerous other huffing drugs.\n\nThese all evaporate fairly quickly if left in open air, which means that particles of them will evaporate from the inside of your lungs into the exhaled air.\n\nSince Alcohol is drunk (in high quantities) and is naturally a liquid (as opposed to Ether) it can be detected for fairly long times in exhaled air.\n\n2. As another poster said, Alcohol is much less potent (requiring larger amounts per amount of drug effect) than other drugs. Examples follow;\n\n- One cup of Coffee contains 80mg of Caffeine\n\n- One Adderall contains between 5 and 30mg of Amphetamine\n\n- One rather strong THC edible contains 10mg THC\n\n- One OxyContin contains between 5 and 30mg of Oxycodone\n\n- One standard drink of Alcohol contains 11000mg of Alcohol\n\n3. Alcohol is a natural decay product of sugars - some apple juice left out in the sun will quickly ferment and taste of alcohol. Because of these trace amounts of alcohol being present almost everywhere (some sources suggest our intestines form some alcohol too while digesting food) our body is very effective at breaking it down.\n\nThis means that Alcohol is eliminated very fast compared to other drugs - 1 dose Alcohol in 1 hour vs 1 dose THC in ~12. This again makes urine testing unreliable.\n\nIt's also that Alcohol is fairly natural, and as such will be hard to detect with enough accuracy. This is also why you can't urine test for Psilocybin, since DMT and closely related drugs are produced in the body naturally.",
"It's not like it would be allowed to use a urine test on the side of the road. Although I would certainly love to see such a process."
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1xx86h | why did birds evolve the attributes needed for flying (hollow bones, feathers, etc) before the ability to fly? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1xx86h/eli5_why_did_birds_evolve_the_attributes_needed/ | {
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"A gliding animal like a flying squirrel or flying snake could benefit from many of the same adaptations.",
"Hollow bones allow for lighter body weight, and therefore higher speed. Birds evolved from small dinosaurs who relied on speed and teamwork to hunt prey. Can't speak for feathers though, hopefully someone else can answer that.",
"Prior to powered flight they likely adapted either as tree based gliders (probably how bats started flying), or as ground based jump and glide (likely how birds started flying), both of which are very good for short quick bursts of travel in the air, which is useful for avoiding predators. After that even partially powered flight (think domestic chickens, which can't fly long distances, but do flap their wings while making short jumps), is beneficial as it extends the distance of travel. This allows for slow and steady progress towards full powered flight.\n\nFurthermore, feathers appear to predate flight. It's suggested that they were useful for insulation prior to being adapted to flight. Also, neither feathers nor hollow bones are present in bats (their bones are adapted for flight, but they aren't hollow), so they clearly aren't a prerequisite for flight."
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ddui1y | how do websites like honey make money by finding discounts? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ddui1y/eli5_how_do_websites_like_honey_make_money_by/ | {
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"They make deals with companies to get special discounts that they can offer to their users. Then they can give part of the discount to the user so they'll use the service, and keep a referral fee from the company. Its worth it for companies to work with them like that because it helps them drive traffic and make sales. I don't think all their coupons are like that though, I think they also make money through ads and I would guess they would be able to get some useful valuable information about what people are buying, but I'm not totally sure on the last thing"
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2q3284 | what's the whole bill cosby scandal and does it seem like he's guilty? | I've been in France for two months, and the first thing I hear upon my return to JFK is about Bill Cosby and his possible assaults or rapes or whatever. Can some one run me through it? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2q3284/eli5whats_the_whole_bill_cosby_scandal_and_does/ | {
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"Cosby had been accused of drugging and raping women several times, and in 2006 he paid a settlement to prevent a civil suit about it from going to trial. \n\nThis was reported in the media at the time, but not widely reported, and it did not receive much attention until earlier this year. Comedian Hannibal Buress mentioned the rape allegations on stage, and for whatever reason, it caught fire. I personally had never heard about the allegations until this happened, and I think I am in the majority with this.\n\nSince then, several women (27 at last count) have come forward saying that Cosby drugged and raped them. The stories are very similar. They were trying to break into acting. Cosby said he would help them. Then he offered them a drink and the next thing they knew they were naked in his bed. These stories go back as far as the 60s.\n\nMy personal opinion, he is guilty. I just can't imagine 27 women all making up the same story, and taking all the risks that come with publicly accusing a famous person of rape. I am not a juror, though, so take my opinion for what it is worth.",
"I believe he is guilty and has gotten away with drugging and raping many women. He is a disgrace and I hope justice is somehow served....Karma. "
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1o74ip | why do some people say that diamonds aren't actually rare at all, but just that some company has a strangle hold on diamonds? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1o74ip/why_do_some_people_say_that_diamonds_arent/ | {
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"[Article covering the topic, including the \"overhang\"](_URL_0_)",
"Because it's true. The De Beers company had a long history of having pretty much a monopoly on the world's diamond supply. With this control they decided that since the value of something is tied to supply vs demand they lowered supply by controlling how many diamonds they sold and drove up demand through advertising campaigns, such as the one that convinced people that the tradition of buying a diamond engagement ring doesn't actually just go back to the 1940s. They then made it so resold diamonds lose pretty much all their value as it was only the original act that gave them value.\n\nThe other reason is because scientifically diamonds are the most common of all the precious stones. ",
"thank you for being so quick to answer this",
"Diamonds became valuable exclusively thru advertising. The practice of giving a diamond ring for marriage didn't become a \"tradition\" until the 1940's. De Beers controls most of the supply of diamonds, and actively discourages people from selling their diamonds. "
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1td34y | i'm thinking of something right before i fall asleep. i roll over and suddenly i can't remember what i was thinking about milliseconds before. why? | Only happens when I'm very close to sleep, particularly if I'm thinking in narrative (telling myself a story in my head). | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1td34y/eli5_im_thinking_of_something_right_before_i_fall/ | {
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"I would really like to know the answer to this..."
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8tpqj8 | so when looking at a substance like water that is clear, are we looking at the atoms themselves or are we looking at the space between the atoms? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8tpqj8/eli5_so_when_looking_at_a_substance_like_water/ | {
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"When you look AT the water, you see the photons that interact with the water molecules and are sent back to your eyes, so you're looking \"at the atoms.\" But keep in mind that the way the photons of light interact with the molecules of water may not carry actual information ABOUT the molecules of water; there are plenty other liquids that are transparent that will look just like water but have completely different molecules.\n\nAnyway, when you look THROUGH the water, you're just looking at the bottom or the object behind the water; similarly to looking at the moon, the space between the atoms in the atmosphere may affect the image you're seeing, but your eyes are focused on the moon, not on the atmosphere / space between air molecules.",
"Here is a cool [Kurzgesagt video](_URL_0_) that explains how our eyes interact with light, and the reason water is transparent.",
"Thinking about it in terms of the space \"between\" atoms leads to a wrong second step - \"clear materials have more space between atoms than other materials.\"\n\nStrictly speaking for you to see through something requires a photon to pass through the space between atoms and strike your eye. However the question of why it passes through one material and not another has nothing to do with this space and everything to do with the chemical properties of the atoms and their bonds to other atoms.\n\nThink of it more like the turnstiles at a subway station. Those will stop an adult from passing through, but they won't stop a rat, dog, or small child. Different materials have different types of turnstiles and for example water, which is transparent to visible light (more or less), is not transparent to most kinds of radiation.\n\nOther things, like steel, which is not transparent to light, is transparent to x-rays. ",
"I feel like all of these explanations are so confusing and I'm not even sure they're right. Basically the light that we see is the light that is REFLECTED by the atoms aka it isn't absorbed by electron in atoms. So an object that we see as red (opaque) has in fact absorbed the other wavelengths of light in the visible spectrum *except* for red.\n\nWhat do i mean by absorbed? Wave particle duality means that light is in the form of a wavelength and a particle. The particle aspect of light is referred to as a photon. Each photon caries a specific amount of energy that correlates to a specific frequency of light which is interpreted by our eyes as different colors. These photons are \"absorbed\" by electrons when they have enough energy to \"bump\" the electrons up to a higher energy level (think about electrons as having specific areas where they can be found and to change the area/orbital they need more energy (this isn't 100% correct but I'm trying to keep it eli5)). When the electron jumps back down from its \"excited state\" it releases the photon. The released photons give off light that is interpreted as a color.\n\nWhy is this relevant to transparency? Transparent objects have chemical characteristics that require a really high amount of energy to excite electrons. This is referred to as the energy gap (think of it as a threshold). Because the threshold is so high, most photons that pass through the material are not absorbed because they don't have enough energy to excite the electrons (it's all or nothing). Therefore the photons pass through and we perceive what is behind the object. This is also how glass works. It has nothing to do with how closely packed together the molecules are (the density).\n\nTo prove this: density of water is 1.0 g/cm3 and normal glass has a density of 2.4-.6 g/cm3 but graphite which is completely opaque has a density of around 2.1/2.2 g/cm3.\n\nSo it just has to do with the chemical character of the object and how high the energy gap is for the electrons. The energy gap is affected by various things such as the elements, bond strength/angle, etc. Also why some compounds have the same formula but some may be transparent while others are not (like diamonds and graphite are both carbon compounds).\n\nTldr as someone said its how the compound *interacts* with the light "
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2pruld | please explain the joke in this webcomic | I am not a native american/english speaker and I feel like ([his webcomic](_URL_0_) is a culture related joke..
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2pruld/eli5please_explain_the_joke_in_this_webcomic/ | {
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"Middle elf has Santa's face so clearly Santa has been having some fun with the lady elves. I don't think this is cultural. ",
"Who's your daddy? Santa!",
"The facial features (nose shape, skin color) of the middle elf match Santa. This implies he is Santa's son."
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2ihpti | why do airlines and/or banks sped so much money marketing credit cards? what's the relationship between credit cards and the airlines? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ihpti/eli5_why_do_airlines_andor_banks_sped_so_much/ | {
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"Airlines love it because it puts passengers in seats, and there's nothing worse than flying a plane with empty seats. They get to place all sorts of restrictions on usage, and you typically pay extras like baggage handling charges on top of everything else even with a \"free\" ticket that air points purchased for you. So they usually only fill up a few seats that might otherwise have been empty (depending on the type of plan), so they're very cool with it.\n\nCredit card companies freqently partner with specific banks, and both love these types of cards because people spend like crazy to build up airline points, often forgetting to pay their balance off every month and thus paying a hefty interest fee. Most of them have interest rates of 20% or so, and as a result if you keep a balance on your card they're gonna make a lot of money. Further, merchants pay a small fee on top of any interest or credit card annual fee that you pay, so they make money off of every transaction even if you pay your credit card balance the very next day. So anything that drives people to spend more on the card is good for them.\n\nIn the middle is the corporation (such as \"Air Miles\") that track points or miles earned. They have arrangements to purchase tickets to either a number of airlines or a specific airline, depending on the company. There's lots of flavours, but they generally act as intermediaries between the credit card owner and the airlines that supply the seat. It's their core business model, so promotion and a partnership with a big credit card company is highly interesting to them too!\n\nSo it keeps four big businesses (banks, credit card companies, air point companies, and airlines) happy, and is very appealing to a lot of customers, and that motivates those companies to spend a lot of money on marketing and advertisements."
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kiz2c | why does shaving with hot water work better than shaving with cold water? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/kiz2c/eli5_why_does_shaving_with_hot_water_work_better/ | {
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"Consider, my five year old, this single piece of dry spaghetti. You can cut it with a knife, but it is hard work, right?\n\nNow, if I soak it in water, it becomes softer and easier to cut. If I leave the spaghetti in a bowl of cold water, eventually it will become soft. However, if the water is warm, it will go into the piece of spaghetti much quicker. In fact, that is what 'being warm' means: everything around us is made of very little bits called molecules. That what we call 'warmth' or 'temperature' is basically a measurement of hoe fast these little bits move.",
"Hot water causes the pores of your skin to open, meaning the blade of your razor can cut closer to the root of the hair. It also softens the beard hair like in the pasta-beard example above.",
"Consider, my five year old, this single piece of dry spaghetti. You can cut it with a knife, but it is hard work, right?\n\nNow, if I soak it in water, it becomes softer and easier to cut. If I leave the spaghetti in a bowl of cold water, eventually it will become soft. However, if the water is warm, it will go into the piece of spaghetti much quicker. In fact, that is what 'being warm' means: everything around us is made of very little bits called molecules. That what we call 'warmth' or 'temperature' is basically a measurement of hoe fast these little bits move.",
"Hot water causes the pores of your skin to open, meaning the blade of your razor can cut closer to the root of the hair. It also softens the beard hair like in the pasta-beard example above."
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4i71fr | on what bases are scores awarded in gymnastics? why was nadia comaneci the first to get a perfect 10? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4i71fr/eli5_on_what_bases_are_scores_awarded_in/ | {
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"In general, most routines/exercises start with a \"base score\" of 10. Judges then deduct fractions of points from the score for various mistakes during the routine. The more severe the mistake, the larger the deduction. A score of \"10\" means the judges identified no mistakes in the execution of the routine. The difficulty of a particular routine/element also matters, as judges are more forgiving of mistakes in difficult elements, and harsher on mistakes during easy elements.\n\nNow, as to why Nadia Comaneci was the first to do it, that's a rather subjective question. Mostly, it was a reflection of how much better she was than everyone else at the Olympics that year. She actually earned seven \"10\"s during that Olympics over the course of the games, 4 times on uneven bars, and 3 times on balance beam.",
"The rules for scoring gymnastics get pretty complicated and seem to change every few years but routines are graded for difficulty and points are removed for even the tiniest mistakes. \n\nThe gymnast or his/her coach submits a copy of the routine to the judges who calculate the difficulty score and then points are deducted from another score, the execution score, during the routine based on mistakes. The two scores are added together for the final score. Certain skills are mandatory in a routine but doing harder versions of those skills lead to a higher score as long as the gymnast can actually perform them.\n\nA gymnast performing a difficult routine with a few small mistakes will get a higher score than someone performing an easier routine perfectly. It's not a perfect system but grading anything artistic comes with some problems. Just look at figure skating."
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3m381e | martin shkreli: enough blind hatred, break down his points. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3m381e/eli5_martin_shkreli_enough_blind_hatred_break/ | {
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" > Comparable drugs are priced similarly.\n\nThe key here is his definition of \"comparable\" drugs. He's not comparing it to other 60-year-old drugs that cost almost nothing to produce. He's comparing it to other drugs that you'll die if you don't get, which are usually very new and for which the R & D has not yet been recouped. \n\n > Drugs are free to those who can't afford it.\n\nMost drug companies have programs to offer drugs to poor customers. The truth is that these programs are there solely for PR purposes; they aren't useful to more than a handful of people because they involve lots of red tape and bureaucratic mismanagement. \n\n > This will ultimately stimulate:\n > a. A better drug.\n > b. Spending on other drug R & D.\n\nThis one is hard to disagree with. If he's charging $750 a pill, other companies have a strong incentive to look for an alternative treatment. Even if it's not as good, they can undercut the current price. \n\n > Other companies hike drug prices without investing into R & D.\n\nThat may be true, but they don't (a) do it by this much, and (b) they don't go out of their way to make a big stink in public about it. ",
"Sure. I'll try. \n\n > Comparable drugs are priced similarly.\n\nThis refers to drugs that are called \"Orphan\" drugs. The drug in particular that he is selling, Daraprim, is not comparable to most drugs. Although it is an antimalaria, it's not a first line or second line drug for curing malaria. The same holds true with Toxoplasmosis. It works to treat the problem, but Clyndamicin does a better job at it. This drug is considered an \"Orphan\" because it used to treat a rare condition that no other drugs that work on the diseases it treats can work on. This Daraprim works really well on HIV-Positive patients, that that's really it. Given how small of a group it works for, there are significantly fewer patients that need it compared to other drugs. \n\nWhen Shkreli is discussing \"Comparable Drugs\", he is specifically comparing it to other \"Orphan Drugs\", for which there are so few people who need them in a given population, the cost of making these pills is significantly less attractive of an option versus other pills that have a much wider reach. Because of the small user-base, it can be argued that prices will go up in order actually break even and/or make a profit from it. \n\n > Drugs are free to those who can't afford it.\n\nYes and no. It depends on whose buying the drug. Medicaid is effectively a free drug program. Medicare and Health Insurance pay out costs for the purchase of drugs. What Shkreli was talking about was the fact that Turing was willing to directly subsidize patients who purchased the drug directly through Turing. \n\n > Ultimately Stimulate a Better Drug and R & D\n\nIt's self explanatory. If you want a better drug that does this, find a new way to make it that works just as well. \n\n > Other companies hike drug prices without investing in R & D\n\nThere are a number of companies who own what is referred to the Manufacturing Rights to produce certain drugs. They are able to rise the prices because they are the sole manufacturer of a drug even though it's not their patent. "
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1sh7ws | how do parapalegics drive? | I have a neighbor paralyzed from the waist down, how do they operate the pedals and such? Thanks!
Edit: He lives alone and drives himself to work. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1sh7ws/eli5_how_do_parapalegics_drive/ | {
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"They have specially customized cars with speed controls on the steering wheels."
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2d3vr1 | how do baseball pitchers throw those really dynamic breaking balls (curve, slider, cutter, etc)? | As a baseball lover, I have always had a question about how exactly pitchers throw breaking balls? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2d3vr1/eli5_how_do_baseball_pitchers_throw_those_really/ | {
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"I'm not a pitcher, but my brother was. Most of it has to do with the position of your fingers on the ball. ",
"Former college pitcher here. The ball has 200+ seams. A pitcher tries to make the seams spin downward really fast, so fast that the spinning (and seams moving air) creates lower pressure under the ball, making it move in the direction of the lower pressure. \n\nHow fast the pitcher spins the seams, how hard he throws the ball, and the weight of the ball determine how unbalanced the force is (how much it curves). The same goes for sliders and cutters, except that the pitcher delivers the seams at a different angle + spin rate. A knuckleball has very little spin, so it dances. I'm no physicist but I think think it has to do with Newton's Second Law of Motion. "
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111hku | why is my gf cold when my body temp. is just right? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/111hku/eli5_why_is_my_gf_cold_when_my_body_temp_is_just/ | {
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"I've noticed that males' hands are generally warmer than those of females.",
"Metabolism=(catabolic and anabolic actions)\n\nCatabolic actions=breakdown of molecules to form a product\n\nAnabolic actions=formation of complex products from simple ones (ex:protein creation form simple molecules called amino acids)\n\n**Edit** Read milliamphour's responses below. My explanation is likely flawed.\n\n\nMales tend to have more of a volume to surface area ratio. Your chest cavity is thicker, your arms and legs have more muscle and fat, and you tend to incinerate more calories on a day to day basis. \n\n\nWhen both you and your girlfriend are jogging, you might feel equally hot. Both of you are burning calories at this point and metabolism (the breaking apart and building of molecules in your body) are in overdrive. When you lay down to go to sleep, however, your larger volume, muscles, and fat stores start to give off more heat to support your metabolism (again, the breakdown and construction of molecules in your body). \n\n\nAfter the jog, your girlfriend might be more efficient at giving off heat because of her smaller volume, and lower metabolism, thus, she will cool down faster. The problem is, she will also be more efficient at giving off heat when she is laying down to sleep, so even if her body feels warm, she is colder than you internally because she is losing heat. You are holding on to your heat better, so you actually can feel cold to the touch without feeling cold on the inside. \n\nAs soon as either of you begin to feel cold on the inside, you start a process of thermeogenesis (heat creation) in most of the cells of your body. Your mitochondria (using O2 and sugar) go into overdrive to heat you back up (catabolic reaction) by breaking down sugars into heat, energy, and CO2. Your body can catch most of this heat because of your larger volume and can kind of recycle it in your bloodstream. As your body warms, the bloodstream carries that heat around and maintains that heat throughout the body. The warmest parts of your body tend to be arteries (fell under your armpits and around your crotch). Your girlfriend is not as efficient at recycling this heat because of her smaller volume, so more heat is lost. In other words, her bloodstream is not as effective at recycling this heat. Keep in mind water also has a high heat capacity (it takes alot of energy to change the temperature) so as your cells heat the water around and inside them (your body is mostly water) the water takes a long time to cool down. As the water in your blood circulates around, you can start to lose heat in your hands, feet, ears, etc. because they are the least thick parts of your body. Sometimes when you feel cold, you bring your hands, feet, and other peripheral body parts (ones far away from the core) towards you. You fold up in a ball to conserve heat. In this case, you are simply increasing your volume to surface area ratio. \n\n\nI hope this helped!",
"A lot of it can have to do with blood flow to periphery limbs, this is also related to metabolism and digestion. If you are experiencing periphery vasoconstriction, they will get less blood and feel colder. Several things can cause this too."
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22il2l | foucault's theories on sexuality | A broad explanation would be good - I don't know where to start. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/22il2l/eli5_foucaults_theories_on_sexuality/ | {
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"Foucault was mostly interested in the discourse of sex - rater than studying the actual history of sexuality, he looked at the way people talked about sexuality during history. So, in victorian times, the prevailing discussion was that sexuality was repressed and foucault looked at why people were saying that. In reality, sex was everywhere and openly discussed so things were obviously a bit more complex than the repressive hypothesis. \n\nI love Foucault and just got told I have to stay at work for four extra hours when I'm not even supposed to be here today so if you want me to get deeper, I'm on it. \n\nThere's also a sparknotes version of his 'The History of Sexuality'. \n\n",
"Let me preface by saying that I am by no means an expert, but I did spend a little bit of time with volume one of his History of Sexuality. There's definitely a lot there, but in my opinion the crux of it lies in his critique of the idea that power, as a concept, is a solely limiting force that is enacted upon a group of people rather than through them and by them. This is what he calls the \"Juridico-discursive\" understanding of power. Foucault understands power as something that enables and produces just as much as it limits. To illustrate this idea and it's relationship to sexuality, he offers that at one point sex acts had nothing to do with any sort of sexual identity or sexuality. He believed the idea of a personal sexual identity, like hetero or homosexuality, was a recent development. Foucault believed that the study of sex and specific sex acts, coupled with the influence of social powerhouses like the church, led to the creation of a social hierarchy around said acts. This then caused some of them to become ostracized. Only once this ostracization took place, were personal identities formed around specific sex acts. So even though power seemed to be acting as a limiting force in this senerio, it actually led to the creation of sexuality and the cultures within it. All that being said, hopefully someone with a more in depth understanding will come along and give you more of the the details that I don't feel quite qualified enough to relay.\n\nEdit: Typo."
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2ysc3f | why is it referred to as the "self proclaimed" islamic state? why not just islamic state? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ysc3f/eli5_why_is_it_referred_to_as_the_self_proclaimed/ | {
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"Because there is no international consensus on the matter.\n\nIt's like someone saying \"I'm President!\" when nobody voted for them.",
"They are also trying to avoid confusion, the Islamic State sounds as if it is the whole of the Islamic world. ",
"Oh! I sort of know this one!\n\nIn international law, there are generally four criteria for being a state:\n\n1. Exerting control\n2. Over a territory\n3. With a population\n4. And the ability to conduct relations with other states.\n\nNobody with any sense is disagreeing that ISIS meets the first three. Sure, their borders are fuzzy, but if you're in north-western Iraq, you are in ISIS territory, and they are the de facto ruling body.\n\nThe question is the fourth one. Now, notice it isn't whether the potential state *has* been conducting international relations, but whether it *can*. North Korea has very limited international relationships, but almost everyone (except South Korea and Japan) recognizes it as a state. ISIS, as far as I know, doesn't have any analogue of a State Department or Foreign Ministry or whatnot. There are no ISIS ambassadors anywhere, nor has ISIS accepted ambassadors from anywhere else. They haven't applied to the UN to become a member. These are the kind of things that you'd need to see for ISIS to be truly considered a state.\n\nThere's also the question of recognition. Not every state is recognized by every other one. For example, Israel and North Korea and Taiwan are recognized as states by almost the whole world, but there are a few holdouts for each. But the fact that Japan says \"North Korea isn't a state\" doesn't make it so. If you had major international players, like America, Russia, France, Germany, the UK, or even Egypt or Saudi Arabia, recognize ISIS as a state and start dealing with it like a state - by negotiating treaties and whatnot - that would be strong evidence to consider that it has met the fourth criterion, and is a state, by international law.\n\nSource: International Law course in law school",
"Why not Da'ash?\n\nSmart kids know that we play interesting semantic games with the names of our enemies. The IS problem is unusual in that no consensus was reached by the persons setting the narrative in the west, and so we ended up with several competing names.\n\nISIS is nice because it links them to a pagan goddess. But it is not accurate, because they have spread from Syria.\n\nISIL contains the word 'Levant' and the Levant contains Israel and the connotations get overheated really fast. So we backed off of that.\n\nIS seems to grant them legitimacy, as though their mock-caliphate was the real deal and all Islam would soon fall in line. This is horseshit. Nevertheless, that's the one that stuck.\n\nIt will not have escaped your notice that these are not english speakers we are dealing with here, primarily. This means that any name for them that expands out into english are either chosen by us to characterize our enemy, or chosen by their frightfully savvy propoganda operation and parrotted uncritically by our media.\n\nThis controversy actually worries me a lot. It seems to signal that we are deeply disunified in our response to this problem."
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87bvaj | i jump feet first into a pool of lava. how long before my body is totally gone? what would be the last parts to melt? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/87bvaj/eli5_i_jump_feet_first_into_a_pool_of_lava_how/ | {
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"Never, actually, boring as that sounds.\n\nFirst, you can't really jump into a pool of lava. It's LIQUID ROCK, and almost as dense as regular rock. You don't really sink into it, unless you're actually jumping into an actively erupting volcano or a strong flow that takes you along and sweeps you into a lava tube or something.\n\nSo as you stand there on your pool, your feet will cook and you'll fall over, and then your whole body will blacken and char and cook\n\n...except your bones. They're made of calcium and don't really melt, just fragment and turn to ash as your fat burns and your liquid boils away. \n\nSo you'll be a skiff of fragile bits of powder lying on top of the pool.\n\n(Yup, Smeagol and the ringie thingie was a lie.)\n"
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jfz3y | what is fairtax? why is it bad? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/jfz3y/eli5_what_is_fairtax_why_is_it_bad/ | {
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"Fair tax is a tax policy that would get rid of the income tax on people and corporations and move the tax entirely to a consumer tax on retail sales.\n\nPeople consider this kind of tax back because it tends to cause Rich people to get Taxed less and Poor people to get taxed. It also gives people a incentive to hoard money which is bad for the economy.",
"Just to make sure we're both on the same page here: Under the FairTax system, people only pay taxes when they buy something (called a \"consumption tax\"). In addition, depending on the number of people in a household, each household receives a certain amount of money each month as a form of up-front tax rebate (called a \"prebate\").\n\nPoor people tend to spend all of the money they earned that year, so all of their earnings get taxed. Rich people, earning enough money in a year that they never have to spend as much of their earnings, will have more money to save. Because the money they save isn't taxed until it's spent, the rich would see less of an immediate effect on the total amount they have to contribute compared to a less wealthy household.\n\nAlso, like grimlock123 said, because people will only have to pay taxes when they spend, they will be more likely to instead save up money which means less money going around in the economy.",
"I've got a yard that I need mowed and I pay two people to each mow half. I'm going to pay each person $10 and afterwards I'll have lemonade and cookies for sale for $1 each. It's really hot out and I have a big yard so because the work is hard I'm going to let the two mowers have water, use the bathroom, and take breaks in the shade. In exchange for this though I'm going to have to place a tax on the mowers. I tax the income of one and tax the consumption of the other mower. This means that I tax how much money the one mower makes up front, in this case I'll tax 20%. The other mower I will only tax based on however much he buys in lemonade and cookies, in this case at a rate of 30% of each dollar spent. So the first mower is done and I pay him $10, however I took out 20% of that so now he has $8, so the most he can buy is $8 dollars worth of stuff. The second mower is now done and I pay him $10. I also pay him an additional $2 as a prebate because that's what I deem the minimum wage to be. He now has $12 and the most he can spend on cookies and lemonade without going over is $9 because the tax on $9 would be $2.70 bringing his total to $11.70.\n\nIt's good to get taxed up front because then you only have to spend one dollar on cookies and lemonade and even though you have less money initially, you can still buy a similar amount of goods if you want.\n\nThe advantage to the fair tax method is that if you choose not to buy any cookies or lemonade you have more money to save for other things. The negative to this is that it encourages you to go buy things somewhere else, where you're money won't be taxed at all once spent.\n\n* as a side not I'd like to comment about what the others have been saying about the Fair Tax encouraging hoarding. There is another name for not spending money besides hoarding and that name is saving. A tax on consumption encourages saving and wise decision making when it comes to purchasing. People don't just hoard money away and never ever spend it. They, try to, save it and make purchases that really count such as a family vacation, a new car, or college tuition versus going out to eat every night or buying a jet-ski. The Fair tax encourages frugality and smarter consumption not hoarding which is burying money in a remote location or something. That's what pirates and bank robbers do, not your average consumer.",
"Fair tax is a tax policy that would get rid of the income tax on people and corporations and move the tax entirely to a consumer tax on retail sales.\n\nPeople consider this kind of tax back because it tends to cause Rich people to get Taxed less and Poor people to get taxed. It also gives people a incentive to hoard money which is bad for the economy.",
"Just to make sure we're both on the same page here: Under the FairTax system, people only pay taxes when they buy something (called a \"consumption tax\"). In addition, depending on the number of people in a household, each household receives a certain amount of money each month as a form of up-front tax rebate (called a \"prebate\").\n\nPoor people tend to spend all of the money they earned that year, so all of their earnings get taxed. Rich people, earning enough money in a year that they never have to spend as much of their earnings, will have more money to save. Because the money they save isn't taxed until it's spent, the rich would see less of an immediate effect on the total amount they have to contribute compared to a less wealthy household.\n\nAlso, like grimlock123 said, because people will only have to pay taxes when they spend, they will be more likely to instead save up money which means less money going around in the economy.",
"I've got a yard that I need mowed and I pay two people to each mow half. I'm going to pay each person $10 and afterwards I'll have lemonade and cookies for sale for $1 each. It's really hot out and I have a big yard so because the work is hard I'm going to let the two mowers have water, use the bathroom, and take breaks in the shade. In exchange for this though I'm going to have to place a tax on the mowers. I tax the income of one and tax the consumption of the other mower. This means that I tax how much money the one mower makes up front, in this case I'll tax 20%. The other mower I will only tax based on however much he buys in lemonade and cookies, in this case at a rate of 30% of each dollar spent. So the first mower is done and I pay him $10, however I took out 20% of that so now he has $8, so the most he can buy is $8 dollars worth of stuff. The second mower is now done and I pay him $10. I also pay him an additional $2 as a prebate because that's what I deem the minimum wage to be. He now has $12 and the most he can spend on cookies and lemonade without going over is $9 because the tax on $9 would be $2.70 bringing his total to $11.70.\n\nIt's good to get taxed up front because then you only have to spend one dollar on cookies and lemonade and even though you have less money initially, you can still buy a similar amount of goods if you want.\n\nThe advantage to the fair tax method is that if you choose not to buy any cookies or lemonade you have more money to save for other things. The negative to this is that it encourages you to go buy things somewhere else, where you're money won't be taxed at all once spent.\n\n* as a side not I'd like to comment about what the others have been saying about the Fair Tax encouraging hoarding. There is another name for not spending money besides hoarding and that name is saving. A tax on consumption encourages saving and wise decision making when it comes to purchasing. People don't just hoard money away and never ever spend it. They, try to, save it and make purchases that really count such as a family vacation, a new car, or college tuition versus going out to eat every night or buying a jet-ski. The Fair tax encourages frugality and smarter consumption not hoarding which is burying money in a remote location or something. That's what pirates and bank robbers do, not your average consumer."
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5emjxt | drumlines | What specific instruments playing what specific parts add up to make that really full sound? Is there a "standard" rhythm that all drum lines know? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5emjxt/eli5_drumlines/ | {
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"A standard drum line is made up of base and snare drums. Generally the snare drums play in unison while doing \"street beat\" (that's the music you hear when the band marches) each individual in the base line will generally play a certain number of beats that differs from the others. When played together, you'll get a really quick, tight sound as if one person were playing everything. \n\nA good drum line will sound like one person playing. ",
"A standard american drumline will have :\n\nSeveral snare drums. \n\n5-7 Base drums each set to a different pitch. \n\nTenor drums, which are either a 4 drum rig, 5 drum rig, 6 drum rig, or 7 drum rig. (5 is probably the most common). \n\nAnd Cymbals either as a permanent part or specific part. \n\nThe warm-ups that they use are generally standard rhythms and routines that help them hone and keep up their skill, but the specific cadences (what the band with march or dance to) is generally fairly unique to each band. Though it should be noted that bands will steal and or modify cadences from one another. ",
"The other two answers so far are good answers.\n\nI was in the hornline, so I don't know too much. But. The snares all play the same part (which is why its so competitive to get in the snareline). The more in unison they are, the better they sound. They sound like one person playing very loud. \n\nThe bass drums however are basically five-ish people playing one instrument. Each bass drummer basically gets one key on the piano, and presses that key at the exact moment they need to to complete the phrase. Counting time in drumline is incredibly important, more so than in the rest of the band. \n\n\n[\nHere's a cool video of BD warming up in 2015.](_URL_0_) Shout out to Naomi on Bass 4!!"
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7e0xw6 | why does being outside in the cold cause a runny nose/other cold like symptoms? i was under the impression that cold weather causing a cold was a myth. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7e0xw6/eli5_why_does_being_outside_in_the_cold_cause_a/ | {
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"A runny nose due to the cold is not the same as having a cold... The purpose of your nose is to warm and humidify and warm I coming air before it gets to your lungs. When it's cold, your nose ramps up mucus production because cold air is dry and it needs more to achieve that goal."
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3ehk6m | what is the origin of cracking your knuckles before a fight? | this is shown a lot in films, shows, and other media: right before someone gets into a fight or threatens someone, they crack their knuckles, usually with the palm of their other hand. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3ehk6m/eli5_what_is_the_origin_of_cracking_your_knuckles/ | {
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"I'm guessing this has an origin in movies. Possibly one scene in one particular movie, or it may have evolved naturally as a movie trope.\n\nA very similar trope is the cocking of a gun. It's almost as if people in movie/TV-land can't aim a gun at someone without it making a \"chk-chk\" sound. That sound is there to add punctuation to the threat - especially if the camera isn't focused on the person bringing the gun to bear at the time.\n\nIt could be that the knuckle-cracking is to tell the audience \"This person didn't just stand up and strike a pose to look intimidating. He is ready to throw down if need be.\"\n\nOr it might be a superstition among pugilists that pre-dates film.\n\nI'd be interested to know the answer. Research away if you don't get a satisfactory response, and let me know."
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93e4vw | how does electricity "know" when to start flowing? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/93e4vw/eli5_how_does_electricity_know_when_to_start/ | {
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"imagine you have a water pump, connect an empty pipe with a tap on the end and it will fill up the pipe with water. (ignore the air that's in the pipe)\n\nthe same thing happens with a wire. if you connect a wire to the positive of a battery the wire also becomes positive.\n"
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fr9ydb | why do goat eyes change shape? | My grandparents’ goats eyes were round in daylight and rectangular/horizontal when dark
Why do their eyes change shape?
I couldn’t find anything about it online.
Maybe I was just looking at two different goats but I don’t think so. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fr9ydb/eli5_why_do_goat_eyes_change_shape/ | {
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"Their pupils are horizontal and will always stay in landscape orientation regardless of how they move their head, like a kind of image stabiliser. This ensures that they can always have maximum visibility to look out for predators. I haven't yet seen a round goats pupil.",
"The darker it gets where the goat is, the more the pupils will expand. This is to let more light into the eye so the goat can see. In sunlight the pupil will contract to avoid blinding the eye. The contracted pupil is rectangular.\n\n\nThe constriction is usually very fast, but it might take longer to have the pupil fully open. This may you might see rectangular pupils even in the shade if the goat just went in from the sun.\n\n\nBoth eyes should change simultaneously , so if one pupil is round and the other rectangular there's usually a neurological problem involved. The same goes for pupils that do not change according to surrounding light."
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kyqj3 | how do land surveyors work? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/kyqj3/eli5_how_do_land_surveyors_work/ | {
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"I know a little about this so I will share what I can.\n\nYou start out with a point of known elevation. This is your Bench Mark. You set up your eyepiece thing on top of the bench mark and then have someone with the measuring stick walk a measured distance away. \n\nAfter looking through the eyepiece you can find the stick-man's elevation with simple math. You continue to do this as many times as you like. \n\nYou can keep your eye piece in one spot and have the stick move around, or you can 'leapfrog' down a slope to find out its changes in elevation. In one of my classes last week we had to cross campus to find the end elevation of a defined point. I can go into more depth if needed, but that is the basic gist. ",
"Like you are five? I will give it a try.\n\nEver see those people in the middle of a street dressed like construction workers looking through weird looking cameras? Those are land surveyors.\n\nWhen you buy a house, and you want to figure out how much land you own and where the boundaries are, you call a land surveyor to tell you EXACTLY where your property lines are.\n\nLand surveyors are people who draw maps of the boundaries of everything from your city to your house in order to determine ownership of land. They draw these maps by using places of reference called landmarks. \n\nIn America in our present time, if you go down the street (look both ways before doing so!) and every so often see these mini-manhole-looking plates, then you are seeing landmarks that have been placed by the government as reference points to draw property lines. In older times, explorers used natural landmarks like the tops of distinguishable mountains (think Half Dome in Yosemite National Park) as reference points.\n\nWhat do land surveyors do with those landmarks? Usually there are two surveyors. One surveyor, let's call her Nancy, sets up her special camera, called a theodolite, on a tripod (surveyors use electronic ones called \"Total stations\" now), and calibrates the camera to be perfectly on top of the landmark. \n\nThe other surveyor, let's call her Lisa, uses a very tall stick with a mirror on the top of it, and goes off into the distance to predetermined points. In the meantime, Nancy uses her camera to point to Lisa's ruler in order to measure the changes in elevation, distance (using the total station's laser), and vertical and horizontal angles of changes. \n\nUsing this method, surveyors have been able to draw everything on the Earth from elevations, terrain changes, dips and valleys, and even your house's property line, to an extremely high accuracy.\n\nSource: I used to work for the City Surveyor in the Bay Area. ",
"I know a little about this so I will share what I can.\n\nYou start out with a point of known elevation. This is your Bench Mark. You set up your eyepiece thing on top of the bench mark and then have someone with the measuring stick walk a measured distance away. \n\nAfter looking through the eyepiece you can find the stick-man's elevation with simple math. You continue to do this as many times as you like. \n\nYou can keep your eye piece in one spot and have the stick move around, or you can 'leapfrog' down a slope to find out its changes in elevation. In one of my classes last week we had to cross campus to find the end elevation of a defined point. I can go into more depth if needed, but that is the basic gist. ",
"Like you are five? I will give it a try.\n\nEver see those people in the middle of a street dressed like construction workers looking through weird looking cameras? Those are land surveyors.\n\nWhen you buy a house, and you want to figure out how much land you own and where the boundaries are, you call a land surveyor to tell you EXACTLY where your property lines are.\n\nLand surveyors are people who draw maps of the boundaries of everything from your city to your house in order to determine ownership of land. They draw these maps by using places of reference called landmarks. \n\nIn America in our present time, if you go down the street (look both ways before doing so!) and every so often see these mini-manhole-looking plates, then you are seeing landmarks that have been placed by the government as reference points to draw property lines. In older times, explorers used natural landmarks like the tops of distinguishable mountains (think Half Dome in Yosemite National Park) as reference points.\n\nWhat do land surveyors do with those landmarks? Usually there are two surveyors. One surveyor, let's call her Nancy, sets up her special camera, called a theodolite, on a tripod (surveyors use electronic ones called \"Total stations\" now), and calibrates the camera to be perfectly on top of the landmark. \n\nThe other surveyor, let's call her Lisa, uses a very tall stick with a mirror on the top of it, and goes off into the distance to predetermined points. In the meantime, Nancy uses her camera to point to Lisa's ruler in order to measure the changes in elevation, distance (using the total station's laser), and vertical and horizontal angles of changes. \n\nUsing this method, surveyors have been able to draw everything on the Earth from elevations, terrain changes, dips and valleys, and even your house's property line, to an extremely high accuracy.\n\nSource: I used to work for the City Surveyor in the Bay Area. "
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5kl9at | why hasn't snapchat sued facebook? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5kl9at/eli5_why_hasnt_snapchat_sued_facebook/ | {
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"Facebook was around eight years before Snapchat. It's been evolving ever since that day, and no one is going to sue a company for having similar features unless code and designs are literally stolen. \n\nThere's no patent on social media features. ",
"Snapchat would need to have invented something unique enough to patent (probably not), patented it (probably not), and then be willing to sue Facebook, a ridiculously rich company with a fabulous legal team who would love the excuse to crush snapchat into the ground.",
"Lots of apps have similar features. If one company is able to independently arrive at a similar feature without any proof of actual infringement on the patent, then there is no case."
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27o42a | why we aren't all just freaking the hell out that we are all going to die and we have no understanding as to why we even exist and no clue what happens after we die? | Seriously.
PS. I kind of have been a lot, lately, after my father died.
Edit: please no religion stuff. I have a faith, and I don't need the sale. The thing about faith is, that's is faith. It means believing without knowing. I'm asking about why we aren't freaking out that we don't KNOW. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/27o42a/eli5_why_we_arent_all_just_freaking_the_hell_out/ | {
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"I think about this constantly. What is all this? How and why are we conscious right now? What is reality? Why does anyone care about Kim and Kanyes wedding when the the amazing wonder of life is way more important? What the hell is happening?!??!!",
"Because it is too late to get scared now.",
"Many people don't know why their toilet's water level doesn't change no matter how much they pee in it. Some don't understand why you cannot pick yourself up and fly away, or recharge an electric car with its own engine output. Most people don't understand why money has or varies in worth, or how a computer works even in general.\n\nSimply put, most people are staggeringly ignorant of the most basic of things around them unless it directly impact their lives. To serve this interest many people have religion; it serves as a standardized method of giving purpose to existence and an ongoing narrative after death, while not actually explaining or proving anything. It may be distressing that it is enough for most people to accept, but I can't help you there.",
"If you where given the opertunity to play a brand new xbox game. Where anything at all was possible. What ever style of game you like it would be. But you could only play it once. Would you spend the entire time your playing thinking about the fact your turn will end soon and you will never play it again. Or would you enjoy the game and make the most out of the experience?",
"If there's an afterlife, that's great- but if not, then it won't matter anyways, I won't be around to be disappointed.",
"I think the reasons people aren’t freaking out for the most part are different for everyone...some use religion, some use distraction, some use denial. I can only speak for myself here though.\n\nI suspect that death will be like before we were born. Nothingness. I wish that there was a Care-A-Lot type of scenario waiting for me after death with angel wings and harps and most of all my beloved grandma (who I would give anything to see again), but I personally just don't think that's going to happen. \n\nI think the reason I don’t freak out constantly about this impending nothingness is two-fold. One, I push it to the back of my mind so I don’t think about it as much (possible denial?) and two, I intellectualize the fear by realizing there is absolutely nothing I can do to change the inevitable and freaking out about it will only cause more stress which could bring about the end faster. \n\nPerhaps there are better ways to go about it though? Maybe it would be better if everyone was more open about the fact that you and everyone you’ve ever known and loved will die...maybe we would cherish life a bit more and not waste it staring at a crappy website for hours a day...but then again..."
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4p4q3s | why is the steering inverted on motorcycles at high speeds? | E.g., when I turn my handlebars left and I'm going 40+ mph, the bike tilts and turns to the right. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4p4q3s/eli5_why_is_the_steering_inverted_on_motorcycles/ | {
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"You are turning the front wheel to the left, the wheel goes left slightly, and the entire bike (and you) keeps going straight. The bike goes from looking like \n\nthis: l \n\nto looking like this: / \n\nSee how the bottom of the bike moves to the left? you have turned the front wheel slightly left, moving the bottom of the bike to the left, and now you and the top of the bike are leaning right. In order to keep from falling over, you bring the handlebars to the right and make the turn to the right.\n\nThis happens the same at any speed, but feels more drastic at higher speeds. Most people don't think about this motion when you turn, but it happens in motorcycles and bicycles. This is just how they turn.",
"Pretty much, to change the the way the bike is turning you have to provide constant force in a direction different than the direction you are travelling in. Turning the handle bars provides a little blip of force that actually does give you a small direction change in the bottom half of the bike. The center of mass tries to stay in line with the direction it was originally moving but the wheels move to the left due to the input at the handlebars to go left. This leaves the bike in a tilt since the wheels have moved out from under the center of mass and you are now in the tilt that results in a right turn. Pretty much the lack of reaction force when the bike is neutrality balanced is why the bike tilts instead of turns when using the handle bars. ",
"It's not. Push right go right, push left go left. A bike doesn't turn the same way as a car, it stays up by means of the centrifugal force of the spinning tires, when you are \"turning\" the forks you are changing the balance of the bike and causing it to lean, which is how you are turning. In a car there are totally different forces at play. This is called counter steering.",
"A bike (motorcycle, bicycle, kick scooter, anything similar) has a very narrow base of support. If you turn the handlebars, say, to the right, you push the wheels supporting you to the right and you fall over to the left. Even if the handlebars are straight at this point, the bike will keep falling because your center of mass is to the left of the wheels. To compensate, you turn left to push the wheels toward your center of gravity and counter the fall, so that you maintain a constant lean angle. You are now in a stable left turn. To exit the turn, turn left some more until the wheels are directly underneath, then straighten out again.\n\nIn short, a bike has higher-order steering. It's the lean angle that determines how you can turn without falling over one way or the other. And to influence the lean angle, you turn the other way. To maintain a turn, you actually turn the 'right' way. It's only the _change_ of turning that's reversed.\n\nMuch of this happens at a subconscious level, and bikes are made so that they stabilize themselves somewhat. You probably don't have to do some of the things I mentioned manually. At 30+ km/h my bicycle goes dead straight unless I make a real effort to turn, for instance; its own turning impulses are very well adjusted to that speed. But this is the physics of it.\n\nI should also mention that this goes at any speed. Again, it's the change of turning that's reversed, not the sustained turn. At low speeds the latter is more pronounced so that's why it may seem different.",
"you should read/watch the movie [Twist of the wrist: Cornering bible](_URL_0_) its a really great video with tonnes of info in it, the cut scenes between the actors are pretty cringe-worthy but the actual info is prime. \n\nYou got a bunch of good responses already, so i wont go into too much detail but it mostly has to do with conservation of momentum, and the angle on the front strutts. they are never set up in a fully perpendicular(90 deg) fashion. and this causes the forces on the bike's two tires, and the momentum of the bike itself to be applied in a way thats not readily apparent. They explain it really well in the video along with a couple other things that are great to learn about riding a bike",
"I'm assuming you're talking about counter-steering.\n\nSo imagine you're in a sweeping left turn, you should be pushing the left handlebar away from you, which turns the actual wheel towards the right. By doing so you're causing the bike to essentially \"fall\" into the left turn to counteract the centrifugal effect of your angular momentum (the tendency to continue going straight, away from center, and consequently in our scenario, fly off the road).",
"All of the top voted comments seems (at the time of writing this comment) to be leaving out the most important factor. \n \nThe wheels on a motorbike or regular bike are not making a flat contact with the road surface like a car tyre does. Think of a car tyre in cross section. It looks like this |__| however a motorbike tyre cross section looks like this U \n\nWhen the handlebar is turned on a bike , as so many here have correctly stated , the whole bike from the forks back leans the other way. Once the bike is leaning if you straighten the handlebars both wheels are now taking the weight of the bike on one side \"of a curved surface\". \n \nIf you took a bike wheel on its own not connected to anything and leaned it to the left and pushed straight ahead the wheel would naturally curve to the left in an arc. \n \nA car wheel doesn't do this because it is making a flat contact with the ground not a curved one. *If bikes had a car tyre style wheel you couldn't steer them this way if at all.* \n \nBy turning the handlebars the opposite way you are leaning the bike in the direction that you want that natural arc the wheel will make to be in the actual direction that you want. "
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fbtgcx | how do animals get the flu in the wild and where does the bacteria originate? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fbtgcx/eli5_how_do_animals_get_the_flu_in_the_wild_and/ | {
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"The virus is just another life form that happens to live in that population of animals. There are plenty.\n\nThe problem with diseases that originate in other animals is that when a different type of host takes it, they're out of equilibrium. It's not actually in the viruses best interest to kill the host, because then it dies too.",
"I think it’s important to note that bacteria are different from viruses. It’s like the difference between honey bees and wasps. Bacteria are just out to live their life and have mainly symbiotic relationships. Viruses just wanna fuck, fuck you up, and be dead inside."
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64fq40 | when did the idea of featuring other artists in songs become the new norm? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/64fq40/eli5_when_did_the_idea_of_featuring_other_artists/ | {
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"I would say it has become more and more frequent in the last 10-15 years, but it's hard to say exactly when. I think a big part of it is that newer artists can showcase their talents with people who are already established, while big names can draw up more interest by grouping up with other famous artists."
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5vafo9 | did people sound like they do in black and white movies in real-life or was it an affected accent? if it was, why did they do it in the movies? | Flair: other | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5vafo9/eli5_did_people_sound_like_they_do_in_black_and/ | {
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"Some people did actually talk like that. Specifically the very rich of New England. It’s called the transatlantic or mid-Atlantic accent. It was specifically taught to kids in boarding schools. Not naturally occurring accent, but one developed to sound kind of British and kind of American.",
"A little bit of both. accents have changed a lot in almost hundred years. You can even notice a difference in just a few decades. In addition there were a notion that there was a standard or better way to talk. So when actors were on stage they cleaned up their accents and used more posh accents. Another major difference is that the movie studios were originally based in New York and used Broadway actors and crew. However as the industry became more focused on movies and not theater they could move their studios west to Los Angles where the weather were better and there were a lot more room for sets.",
"This applies very much so to the Australian accent. If you compare videos from the 1950's to modern accents you'll be amazed. The typical Australian accent these days is very strong, harsh and almost lazy. But you see videos of Australia in the mid 1900's and they all speak very proper and posh. Not sure if this was the way the TV/Radio presenters were trained to speak or if this was normal. Would love a reply to this for an ELI5",
"IT's both. The accent was 'real', but unlike most accents, it was a cultivated one. The one you are talking about would be either [received pronunciation](_URL_0_) from the UK or more likely, the [transatlantic](_URL_0_) from the US (heavily influenced by the UK version). Basically, some (mainly very wealthy) people trained themselves to speak a particular way that was seen as 'correct'. These accents are also heavily associated with theatre and film of that era. "
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cf1xxp | do memories occupy a physical space in the brain? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cf1xxp/eli5_do_memories_occupy_a_physical_space_in_the/ | {
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"Memories are pretty much connections between nerve cells, the more numerous \n(edit: and stronger) the connections the better you can remember something. \n\nSince this is a physical connection, theoretically there is a limit to how much we can remember. However we dont know how much of our brain is available to store memories so we really cant determine what that limit is.",
"They’re frequently called memory traces as they’re more patterns of brain activity. Though the simplest form of a ‘memory’ would be the connection between two neurons, as with repeated firing between them, the connection gets stronger. This is the basis for what most people believe constitutes memory and active learning.",
"Yes.\n\nAll memory is technically physical evenwith computers. I mean an electron isn't any less physical than the atom it comes from.\n\nIt's not as simple as loctating a sector in your harddrive and locating a file. But memories are thought to be sets of physical neurons formed and reformed over time for a specific stimuli.",
"Yes. Your brain, the physical container for the mind, is by definition a physical space; with it's blend of electrical signals and nerve networks, it's incredible growth once language and the frontal cortex exploded - all of those somehow are the physical holders of \"memories\" and their triggers, including smell, music, and more. Somehow molecules in salty water and membranes and constant lightning create it",
"Technically, no.\n\n & #x200B;\n\nThe neurons that are able to form the memory absolutely occupy a physical space.\n\n & #x200B;\n\nBut each neuron only stores a part of each memory. How they connect and fire determine what memory is recalled. This process does not have any physical space. It is solely a combination of neurons, which occupy a physical a complete space, but also have multiple jobs.\n\n & #x200B;\n\nThus, each full memory you recall is a combination of neurons, each acting together to form the memory. The memory itself only exists because these neurons fired and linked in a certain pattern.",
"As you ride your bike down the grass hill in the same way every day, the path will first start to be obvious by the grass all laying down in the same direction after a day or two. After you keep riding down the same path on the hill, the grass will eventually carve further into the ground and make a wider path and begin the carve into the ground. Your familiar feeling with things are attributed to your memory of the things. In the same way that your bike will create a dirt path in the grass over time as you ride it again and again, the memory becomes stronger and more established the more you experience the room or event or experience.\n\nJust as the dirt path your bike makes doesn’t occupy more space, but does hold the information of the path - your memory “paths” in your brain do not occupy more space in your brain.",
"I forget where I saw this explained, but memories do not actually *exist* so much as *happen*. They're not like data on a hard drive; they are more like a radio signal getting picked up by an antenna.\n\nA memory occurs when nerve cells in a certain part of your brain repeat a pattern of electro-chemical signals that is similar to the pattern that occurred at the moment of the event you are remembering. If something prevented you from establishing the initial pattern, you won't be able to remember a thing later, no matter how hard you try. This is why things we once knew, and forgot, we might someday remember, but you never get back the events of last night when you were too drunk to remember your own name.",
"So, neurons are connected to each other. The neurons themselves aren't really responsible for storing information. The information we know it's encoded in the connections between them. Or rather, the pattern between them that gets activated (meaning that they respond strong enough to some input to \"turn on\") given some input.\n\n\nImagine a spider web. Let's say that web represents the concept of a bicycle. If you add a small stand, but the web otherwise stays the same, that probably represents something really similar, but different, than a bicycle. Maybe a unicycle or skateboard or handlebars. Add and remove strands and each \"pattern\" represents something different in this way. These webs are different for everyone, though there are commonalities. So, the web the activation \"web\" that means bicycle for me might not have much of anything to do with the one that name bicycle for you.\n\nSo, when your eyes, ears, nervous system etc send signals into the brain it sort of \"falls through\" the chain of neurons activating different paths that have been conditioned to respond to that type of signal (which is why odd things sometimes remind us of seemingly unrelated stuff, because part of one web was similar to another. So, smelling eggs might remind you that forgot to hang up your car keys , as an example).\n\n\nThis explanation is kind of contrived, but at a high level, it gives an idea of how \"information\" gets kept in our brains.",
"The truth is that we aren’t fully positive on how and where memories are stored, but there is a strong theory that I support.\n\nImagine you walk into a library. You want to find a specific book, so you go and look on the computer and you find the location of where that book is. Now instead of having one location for the book, each page is stored in a different place, but you have the locations of every page.\nSo you go and hunt down each page, and now you have the full book!\nTo add another layer to this, imagine you just have a pretty solid idea of which pages are in this book and in what order they go in. Each time you find the pages and make the book, you have to later take the book apart and put the pages back.\nDo this enough, and things can get a bit messed up, and the book isn’t really the same as it was the first time.\n\nSource: I am a neuroscientist",
"“Memory” means “something remembered from the past; a recollection.” So by definition it can’t possibly exist physically. It’s a logical state of certain arrangements of your physical brain (which exists prior to the recall.). So technically “memory” doesn’t occupy addition physical space, but the fact that you can recall requires a physical brain.\n\nPut simply a memory is a function of the brain, like intelligence. Intelligence doesn’t have a physical property, it can’t have. Just like any adjective aren’t nouns.",
"They initially were searching for these engrams, or specific places in the brain where learning could be observed. \n\nLater the neural pathways and the strengthening of these were more widely accepted. Where the principle of \"use it or lose it works\" - they could spontaneously come back. And if you're interested in this process you could read up on \"hebbian learning\". Very interesting stuff! \n\n & #x200B;\n\nInterestingly the study of taxi-drivers in London have shown larger areas of the hippocampus than in normal individuals. Same with musicians with highly specific skills. So this could be some evidence for specific enlarged areas due do learning. But the chicken or the egg problem comes up here. We're the taxi-drivers more prone to learn because of a larger hippocampal area or did it grow due to learning?",
"One fascinating fact that may have been mentioned is that some memories are stored elsewhere in the body, not just the brain! They discovered this with transplant patients.\n\nHere’s one example:\n_URL_0_\n\nOr another one:\n_URL_1_",
"I hold the unpopular view among people in my field (philosophy of mind) that the answer is \"no.\" Obviously, any number of physical events occur in the brain when we remember something. However, none of these things have the inherent nature of memory itself. Memories have content. They are about something, and the thing that they are about is represented to the mind when memories occur. The representation has certain features such as a meaning, an intellectual acceptance of the meaning, a mode of presentation that differentiates it from other types of mental states about the same thing, and, in the case of experiential memory, any number of qualitative features of experience like what things looked like. None of these seem to be anything like anything that is happening in the brain. Patterns of synaptic activity and chemical production bear no resemblance whatsoever to a mental image of eating breakfast last Tuesday. The imagistic qualities aren't there, the \"about-last-Tuesday-ness\" isn't there. \n\nPeople in philosophy of mind have tried to explain how the features of a memory could be nothing more than the brain activity that was present when the memory occurred. No answer has received wide acceptance and all of them face serious problems. Most people in the field are sure their view must be true, so they keep trying. Some of us think this is a waste of time. You can't explain how one thing is the other because they are two different things. Mental states aren't part of the physical world because minds are a distinct, non-physical part of us. Dualism about human nature has actually been the default view of human beings throughout history. You mind or soul or spirit is a part of you that us distinct from your body. It is the thing religions tell us goes to heaven or gets a new body when we die. Currently, academics look down on this view. But the view seems built into how people conceive of themselves, and the idea that thoughts have electrical wattage, memories have a certain number of proteins, or wishes take place in squishy gray stuff still sounds confused and ridiculous to the un-indoctrinated (they would say \"uninformed\") ear. So, I stand with the unwashed masses in saying the correct answer to your question is \"no.\""
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266f82 | what is cybernetics? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/266f82/eli5what_is_cybernetics/ | {
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"AFAIK it is a cross-branch study of how everything depends on everything. Something like how the entire internet is one big spiderweb of different and seemingly unrelated issues that have a common line between them, cybernetics aims at studying how the different types of systems in the environment around us interact such as the dependence of biological organisms, mechanical systems, the science behind the explanation for that link based in chemistry or physics, etc. I believe it even includes bits of psychology such as social behavior and so on. The ground principle assumes that the entire link between them all works on a system of feedback that passes information along the line.\n\nAs an example, the food chain starts from photosynthesis in plants from the absorbed sunlight that goes into stored nutrients. This is consumed by other animals. When they die, their body hydrocarbons decompose to the nutrients in the soil. But, starting to probe deeper. How does the sunlight have that energy and how does it get to the earth so far away? What is the nature of the plants that allows photosynthesis? What is the chemical constituents that aid this? How does the animal know which bits are good for consumption? How does the animal interact with others of its species to either protect its food or share with the others? Is there any way to influence this cycle or alter the behavior that can change the effects? Are there any other cycles that interact at a common stage? Questions like this can go on forever and requires the understanding and collaboration from experts of all fields of research and study.\n\n_URL_0_\n\nHope the wiki page helps\n\nTLDR: Study of how everything relates to everything else\n\nEdit: Some format issues"
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wnofg | how do you speak louder? | What can I do to naturally turn up the volume of my voice? When I'm out in public, people crane their heads toward me or they ask me to repeat myself several times. This is after I'm at a level just short of shouting. Any suggestions? Exercises? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/wnofg/eli5_how_do_you_speak_louder/ | {
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"Put your hand on your belly. Now practice inhaling and exhaling in such a way that your belly expands and contracts, moving your hand outward and inward. Once you've got that down, practice talking loudly while making your hand move inward. ",
"it's more than just loud. what watabit is getting at is using your [diaphragm](_URL_0_) to project your voice more. if you have ever seen some public speakers or actors they are able to get you to hear them from across the room while maintaining a tone that isn't shouting. \n\n\nhonestly i don't have any good tips for achieving this, some find it easier than others. try googling around on \"projecting your voice\" ",
"WHAT'S THAT? I CAN'T HEAR YOU, YOU'LL NEED TO SPEAK UP"
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atl249 | automatic windshield wipers | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/atl249/eli5_automatic_windshield_wipers/ | {
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"Some cars have water sensors somewhere on them. When they get wet, their electrical conductivity changes. The car's computer detects this and turns the windshield on. Advanced ones can even detect the rate at which water is coming, meaning they can adjust the speed as well."
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2g9xb1 | i switch my tv off at the wall, but the little red standby light stays on for nearly a minute afterwards. how? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2g9xb1/eli5_i_switch_my_tv_off_at_the_wall_but_the/ | {
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"[Capacitors](_URL_0_) store electricity. This is why many electric appliances have warnings that you shouldn't poke around in them, even if unplugged. Some hold enough charge to stop your heart if you short it.",
"Capacitors in tv still have residual charge once power is cut, hence the delay between power light as the current drains."
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60zcu7 | why we can't be friends with russia now that leadership has changed since the cold war, and how its justifiable to be friends with cuba even though they were the biggest concern in the cold war. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/60zcu7/eli5_why_we_cant_be_friends_with_russia_now_that/ | {
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"Russia has absolutely no interest in being \"friends\" with the US or the West. They want their status as a superpower back, and that would certainly come at the cost of lowering the west's power, influence, and ideals. Russia has zero interest in being a \"good\" partner, they want back what they lost and being \"friends\" is not going to get them there.\n\nTo an older generation, this seems quite normal. To a younger generation, who grew up or were born after the cold war, they never see (or saw) Russia as formidable and intense foe. They see them as a nation that is struggling, had fallen apart, that isn't strong, that isn't a threat, and nominally been allies, they weren't the enemy that they were even just a few years before, they are seen as weak. An older generation, and all of Russia do not see that. Russia fell, hard, but Russia sees it as a temporary setback before they get back to their roots and are a formidable foe again, and a world power to be reckoned with by all.",
"1. Cuba was absolutely NOT the biggest concern in the cold war. \n\n2. You can't be friends with a country ruled by a corrupt, expansionist dictator. Especially not one who has meddled in our country's election. ",
"Just having diplomatic relations doesn't at all mean that two countries are \"friends.\" It merely means they are *friendly enough to at least talk to one another.* There are relatively few countries in the world that the US doesn't have formal diplomatic relations with (Iran, North Korea, etc.)\n\nRussia is virtually guaranteed to be a rival of the US- in one form or another- for as long as it exists as a country. This is because Russia is a semi-superpower of sorts, yet has very, very different perspectives on what an ideal world order looks like. This difference in perspectives is largely rooted in Russia's history and geography, which differs considerably from the United States. For example, Russia suffered three devastating invasions with a 150 year period. This has made Russia paranoid about its neighbors, and so it consistently attempts to aggressively carve out a barrier around itself (keeping Georgia in line, keeping Ukraine destabilized, etc.) \n\nThe Cuba situation is much different. One could make a case that the longstanding embargo and freeze in diplomatic relations was more a reflection of US pettiness than anything else. "
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1nxx8w | how does insurance fraud even work? | With the recent dashcam fail vids, how does insurance fraud even work? The "victim" would probably be injured enough or even killed so that they can't see or track the car that "hit" them if the driver drives away. Also how are the "victims" even able to prove that this person hit them? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1nxx8w/eli5how_does_insurance_fraud_even_work/ | {
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"Get insurance on something, break it on purpose, tell the insurance company it was an accident, get money."
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vk7lz | how do capacitors work and what do they do on a motherboard? also why do they leak? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/vk7lz/eli5_how_do_capacitors_work_and_what_do_they_do/ | {
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"Think about capacitors as a water holder with large hole to fill but it has a small hole that leaks the water anyway. It takes short time to fill it up but longer time to empty, it's used in electronics to save the electric charge for sometime.\n"
]
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[]
] |
||
40qp6q | what would happen if the us adopted a compulsory voting policy? (i.e. fine/community service for people who don't vote) | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/40qp6q/eli5_what_would_happen_if_the_us_adopted_a/ | {
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"In other countries where mandatory voting is implemented, such as Egypt and Peru, citizens indicate in exit polls (by majority) that they couldn't explain why they voted for the person they did. In short, compulsory voting would not make voters more educated and informed about the people running for office, and thus makes it more likely for an unqualified person to win an election, because people are voting on a whim.\n\nWhat we can do is make voting easier for interested citizens. Not allowing these Voter ID laws that certain parties are pushing would be a good start. Same-day voting and online registration have also helped voting numbers in the past.",
"Wikipedia says research shows it has a significant effect: _URL_0_\n\nPoor people have more barriers (have to work, don't have a car, cultural importance of, etc) to voting than others. Also looking at the voter turnout for college kids is depressingly low - they tend to have some education on the issues and candidates but can't seem, on average, to organize themselves into actually voting (busy or lazy?).\n\nI'm pretty sure both parties want this to happen in the US about as much as they want a hole in the head. So what would happen is you'd see pigs flying and hell freezing over."
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2bp2it | if your heart has roughly 1 billion beats before natural failure, why is cardio exersize good for you? | Is it the same principle behind other muscles? Working them out makes them stronger? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2bp2it/eli5_if_your_heart_has_roughly_1_billion_beats/ | {
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"Two reasons.\n\n- Cardio doesn't just exercise your heart. It exercises your lungs and your muscles associated with endurance. This helps your body a LOT, doing things like assisting your metabolism to keep your weight down, adding to your bone density from the impacts, lowering your blood pressure, and increasing your stability so you won't fall and break a hip. \n\n- And your heart has *roughly* a billion beats, there's no ticking countdown clock. Some people get way more, some people get way less. It's more of a rough general observation than any sort of limiting estimate or warranty period.\n\nP.S. fit people have lower beats per minute than unfit people, offsetting the extra heartbeats that occur when they exercise anyway.\n\n*LATE EDIT: A lot of people have already pointed out that the average lifespan of a human means closer to 3 billion beats. Just pushing that up to the top for accuracy.*",
"The 'one billion beats' concept comes from an observation that short-lived animals tend to have higher resting heart rates than longer lived ones.\n\nThe typical human's resting heart rate is 60-100 beats per minute, and many live to about 70ish. Assuming an average of 80 beats per minute (times 60 minutes, times 24 hours, times 365 days, times 70 years) the typical person lives closer to 3 billion beats.\n\nCardio is good for you because the idea that you live one billion beats is super wrong.",
" > Is it the same principle behind other muscles?\n\nSort of. Your heart is a muscle that can atrophy and hypertrophy like other muscles. By strengthening your heart muscle, you make it more resilient and it will beat stronger. By the same token, working out also helps increase your circulation by increasing your cardiac output. Basically, you keep the blood flowing stronger through your blood vessels. Healthier blood vessels means your heart doesn't have to work as hard to pump the blood which means it works less. \n\n > \"If your heart has roughly 1 billion beats before natural failure [...]\n\nI'm kind of confused as to where you're getting this number OP. The average, healthy heart beat is 60-100 bpm which is just for an adult. A neonate is actually more like 100-160 (or something like that, can't precisely remember); children are higher too, something like 80-120. Anyhow, Even insofar as if we just focus on a normal adult heart beat with a normal adult cardiac rhythm, you would have:\n\n* 80bpm X 60 min = 4800 beats per hour (bph)\n\n* 4800 bph X 24 hr = 115, 200 beats per day (bpd)\n\n* 115, 200bpd X 365 d = 42,048,000 beats per year\n\n* 1,000,000,000 / 42,048,000 = 23.7 years\n\nAssuming you live to be 80 years old, factoring in some rough averages of HRs for babies/children etc, your # of beats, lifetime, would be somewhat closer to 3.49 Billion. This doesn't even include such things *as* periods of cardiovascular excercise, stress or illness. Nor does it take into account periods of sleep where your heart rate will decrease. However, overall that 1 billion sounds suspiciously low. \n",
"I'll make some assumptions in this post, but I'll try to be liberal with my estimates. Pardon the formatting and typos, I'm on my phone. \n\nLet's assume our fictional person is 30 years old.\nAverage resting heart rate is 60-100 bpm, so we will assume 80 bpm. \nMaximum heart rate is estimated as 220 - age. So we have a maximum heart rate of 190 bpm. \nTarget heart rate is typically 60-80% of the maximum heart rate. Let's assume the highest, this gives us 162 bpm. \n\nThis person, with no exercise routine in place has an average resting heart rate of 80 bpm. \n115,200 beats per day = 80 bpm * 1440 minutes per day\n\nNow, what if this person exercised for one hour per day and hit their highest target heart rate. \nTotal beats per day = 23 hours at 80 bpm and 1 hour at 162 bpm. \n120,120 = 1380 * 80 + 60 * 162\n\nThis is a difference of only 4,920 beats per day. \n\nSomeone that exercises regularly has a lower resting heart rate than someone that doesn't exercise. In a highly trained athlete this can be as low as 40 bpm, but obviously that isn't possible with only one hour per day. Let's figure out how much lower the resting bpm needs to be for that 4,920 to be \"negated.\" \nDifference in bpm = total difference / non-exercise minutes per day\n~3.57 bpm = 4,920 / 1380\n\nIf that hour of running per day lowers this person's resting bpm by just 3.57 bpm, they will \"run out\" of heart beats at the same time. It is very likely that their resting heart rate will be significantly lower, 15-20 bpm lower, giving them more time. "
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1ek072 | the large increase in the cost college today compared to the '80s and it's relation to the rise of student loan debt | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ek072/eli5_the_large_increase_in_the_cost_college_today/ | {
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"I wrote this about six months ago, just my opinion. I hope I broke it down well enough, I'd be glad to answer any questions you have! \n\n_URL_0_"
]
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[
"http://keepwhatsyours.blogspot.com/2012/09/rising-cost-of-education.html?m=1"
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||
3chkou | why doesn't water go into your various holes when you take a bath? (possibly nsfw) | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3chkou/eli5_why_doesnt_water_go_into_your_various_holes/ | {
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"apparently, a BOT flagged my comment, so ill say it again:\nthe body is made up of various muscles that cling to prevent the release of fecal matter and bodily fluids. \nthe body also has internal pressure than prevents entry of liquids to certain parts\nscrew you ellen pao "
]
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[]
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||
3hv8we | why are chinese people in the uk buying so much baby milk powder? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3hv8we/eli5_why_are_chinese_people_in_the_uk_buying_so/ | {
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"They don't trust the shit they can buy in China. It wasn't too long ago that people were caught [intentionally poisoning milk products to increase profits](_URL_0_).",
"No one trusts the baby formula/milk poweder in China, so there's a huge gray market for the imported stuff. ",
"Some years ago some Chinese milk powder products were found to contain melamine which caused 6 kids to die. This lead the Chinese to distrust their own milk powder and they'll easily lay down 60 euro's for 'our' product (it is a problem in the Netherlands as well).\n\nThat is only half the story. The solution would be pretty obvious; why don't we export/sell more milk powder to china? The answer to that is that, in order to legally import, you need to have your list of ingredients and other texts in Chinese. So even if you have two identical cans of powder, one with Chinese writing and one in Dutch, the Chinese will buy the one with the Dutch writing because they believe it is better. They think we export the low quality to china and keep the good stuff ourselves, or that during the transport the government adds some melamine to the mix.",
"They do the same thing here in NL. In the supermarket where my brother works they bought up all the baby food; now you can only buy one jar per person. Our theory is that they send it back home and/or distribute it among friends and family for a discount."
]
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57hhew | how can you poll a small population (1-2 thousand) and use it as an estimate for how hundreds of thousands will vote? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/57hhew/eli5_how_can_you_poll_a_small_population_12/ | {
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"Because that's how it works. A poll's goal should be to exactly reflect the way the actual voting public will vote. You can't really measure this until after the fact.\n\nAfter the vote is taken, if your polling methodology yielded results similar to the actual voting public, you have been successful, but you still refine it. For example, you only poll people who state they are likely voters (as opposed to people who are just registered voters). No amount of refinement will get you to the way the public actually votes, so a poll will come with a margin of error. This margin shrinks as you add more people to the poll.\n\nIf you look at [Nate Silver's site](_URL_0_) He aggregates polls, assigns a weight to them (based on their past accuracy) and then adjusts them (some polls always skew predictably to one direction away from actual voting, but if the skew is consistent, it can be adjusted).",
"It's called the Law of Large Numbers.\n\nSay we were polling a class of 40 students for favorite ice cream flavor, and there were two options (vanilla, chocolate). Suppose that, across the whole population of 40, 15 students liked vanilla and 25 liked chocolate. So 37.5% of the class likes vanilla, and 62.5% of the class likes chocolate.\n\nYou ask one student. He says he likes vanilla! Well, with a sample size of 1, you could say that 100% of the class likes vanilla! That's not very accurate, is it? Then you ask a second student. She says chocolate. Now it's a 50-50 split. As your sample size increases, you will very quickly get close to the 15-25 split of the full population.\n\nThe important thing in polling is to ensure that your sample group is random and representative of the full population. If you only ask boys which ice cream flavor they prefer, you might skew the result. In a presidential election poll, you have to make sure your sample includes people from a representative spread of economic status, race, location, and age (and probably some others I'm forgetting). You can't just call a thousand people and get a thousand answers. Polls that are done properly are very strong indicators of the opinion of a population. Polls that are done poorly are not."
]
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9t2z6d | why is corn so different from other grains? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9t2z6d/eli5_why_is_corn_so_different_from_other_grains/ | {
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"Several millenia of selectively breeding for more and larger grains. Ancient corn looked much closer to other grains. ",
"Corn were domesticated in America while all the other grains were domesticated in Asia. There is still a wild variant of corn which is very similar to other grains in both size and looks. Your description of wheat is a bit off though. The individual grains of wheat grows close together, even touching, forming an ear which is very similar to a corn cob although much smaller. The only distinguishing thing about corn is its size. And the size is a result of selective breading in a different direction then the Asian grains were. It is probably possible to start breading wheat in the same way and end up with wheat ears that is similar to corn cobs if you spend a few thousand years on it."
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a0zd1f | why are wood baseball bats in mlb milled to have a concave bore at the tip? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a0zd1f/eli5_why_are_wood_baseball_bats_in_mlb_milled_to/ | {
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"There are several reasons, the biggest of which are removing weight to increase swing speed, and improving the overall balance of the bat.\n\nSource: Catcher from 2nd place 1992 Little League team. "
]
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||
1494h4 | if i can hold my breath underwater for let's say, 5 minutes...why doesn't it take someone 5 minutes to choke me to death? | Let's imagine a scenario where I'm being choked by the neck and I am remaining completely calm...just focusing on holding my breath. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1494h4/if_i_can_hold_my_breath_underwater_for_lets_say_5/ | {
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"well inside your neck there are little tubes called arteries and veins. when someone squeezes your neck it cuts off the blood flow to your brain. if you just hold your breath then your blood flow is not cut off. so its lack of blood flow to your brain that kills you. it is possible to choke someone unconconcious within 3-5 secomds",
"Wait, what? You can hold your breath for 5 mins?\n\nI last about 60 secs. You dolphin.",
"Choking restricts both the flow of air to the lungs and the flow of oxygen to the brain. If you were choking someone in such a way you were only blocking air flow, they would last for a few minutes."
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1r96au | why can we not/do we not store and reuse as much expended energy in cars as possible? | So I have the image in my head of a vehicle. When it turns, something in the car tilts because of that turn. That turn creates a charge, and that charge is stored in a battery tank housed in the floor of the trunk. The driver accelerates, and the rear wheels of this FWD car store more of a charge in the battery tank as the car's speed increases. The stereo turns on, and vibrations in the car are felt through a sensor in the dash, which is stored in the battery tank too.
I know hybrids work by switching over to battery power when they stop, and I know energy is expended in so many varying ways that we use cars. I just don't understand what limits us from doing something like this to all our cars. I figured that maybe this stuff wouldn't add up much, but over time it would. It's like leaving some change in a bucket after every purchase: You may end up with a ton of money before you know it. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1r96au/eli5_why_can_we_notdo_we_not_store_and_reuse_as/ | {
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"You don't get energy for free. Any thing you hook a generator up to produces drag (friction), making it harder to create the motion in the first place. You'd just wind up burning more gas.\n\nHybrids and electric cars *do* regenerate when stopping. They take advantage of the increased friction needed to pull some energy back into the battery.",
"First two ideas that spring to mind:\n\n1 - added financial expense to the vehicle makes it less likely to sell compared with competition.\n\n2 - added weight from all the didgeridoos mentioned, resulting in increased fuel consumption and therefore lower efficiency at best equal to the energy regained but probably not.",
"Turbocharging is one way to increase thermo-efficiency. It does normally wasted exhaust gases into a mechanical means to increase compression in the combustion chamber, therefore increasing efficiency. A lot of the heat energy in a naturally aspirated internal combustion engine is wasted. "
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12sscn | what makes a circular paper airplane fly so well? | Like this one: _URL_0_ | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/12sscn/what_makes_a_circular_paper_airplane_fly_so_well/ | {
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"Sorry no answer, but [better vid, with actual flight.](_URL_0_)",
"Stability.\n\n1. Circles are very hard to deform compared to other shapes. This means the \"wing\" will not flutter or collapse, which is the main problem when working with paper.\n\n2. Having all of that weight at the bottom means it won't flip over, and won't roll over. It also looks like it is placed so that the more it begins to nosedive, the further forward the center of lift moves, keeping it level.\n\n3. Straight wings make lots of whirling, messy air from their tips (like when you push your hand through a bath of water). These both slow the plane down because it has to pull the big balls of air along with it, and shake it about (point no. 1). In some passenger planes you can see little vertical \"winglets\" on the wing tips, which help reduce this. \"Circular\" wings have no tips, so they don't have this problem at all!"
]
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"http://www.youtube.com/watch?v=k8Yehe2dbyQ"
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7diuax | how do countries handle the vast discrepancies between international postage costs? | I've got a rough handle on the [Universal Postal Union](_URL_0_) but I'm still not entirely sure how they handle the nuances of balancing the books when it comes to international postal charges.
Let's say I buy something off eBay from China, and have it mailed to me in Australia. The seller in China pays China Post all of $1 or whatever low price they charge to ship it, and the item makes it all way the to Australia, where it gets handed over to Australia post - who have to invest considerably more than $1 worth of resources and effort to get that item to me. In fact, if I was to mail the same item across the city here, it would cost me about $8 or so.
Since the number of people in Australia buying stuff online from China vastly outweighs the number of people in China buying stuff from Australian online retailers - how, exactly, do Australia Post and China Post reconcile the books to take into account the fact $1 isn't even close to covering the cost of getting something delivered in Australia from their end?
It makes more sense with sending from places like the US or UK, where the postage charges more or less seem to even out and the parcel traffic between the two countries is probably relatively similar.
Are there minor diplomatic incidents over these things? Is the Postmaster General of China telling the Postmaster General of Canada that it's too bad everyone in Canada wants mail from China but there's only so much maple syrup people in China want mailed to them? Or is it one of those situations were everyone agrees it's all out of whack but the international postal service is important enough that they just let it slide? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7diuax/eli5how_do_countries_handle_the_vast/ | {
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"There is an organization called the Universal Postal Union that helps sort things out. Established in 1874, it is perhaps the oldest international governance organization in the world. It is now part of the UN.\n\nThey have a system to balance the books when there is a mail imbalance between countries, where in your example China would have to compensate Australia. In addition, some countries, like the US and China, have a bilateral agreement on how to handle postage imbalances.\n\n",
"The receiving country is supposed to charge the sending country a certain amount for delivering mail that was paid using stamps of the sending country. The same is true the other way, so countries just work it out between themselves.\n\nIf China Post is losing money on mail sent to Australia then they will eventually increase the prices (or not, they may be happy to take a loss on certain destinations, the government may want to keep the price down, etc)"
]
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6npfnz | if it's the other harmful chemicals in cigarettes that give cancer etc rather than the nicotine itself, why can't we mix nicotine with other non-harmful chemicals since people only smoke cigarettes for the nicotine? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6npfnz/eli5_if_its_the_other_harmful_chemicals_in/ | {
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"text": [
"Isn't that what a vape is?",
"You can, that's the idea behind the patches, nicorette gum, and vaping.\n\nNicotine itself isn't completely harmless though, stimulant addictions bring their own issues.",
"Nicotine isn't harmless. It was used as an insecticide in WWII but dropped because there were cheaper alternatives that were *less* harmful to mammals.\n\n[\"Nicotine is well known to have serious systemic side effects in addition to being highly addictive. It adversely affects the heart, reproductive system, lung, kidney etc. Many studies have consistently demonstrated its carcinogenic potential.\"](_URL_0_)\n",
"Well you can, and that's why people vape. There's different strengths of nicotine involved with vape juice. People who smoke 1-2 packs a day will take a higher nicotine content juice. But I'm not exactly sure why people do just switch over. After all vape juice has 4 core ingredients (natural flavoring, propelyne glycol, vegetable glycerin, and nicotine). Some say there is a harmful chemical in vape juice that causes \"popcorn lung\". However that was in the old days of vape juice when there wasn't a whole lot of science involved (and probably the vape juice that you can buy behind the register at a gas station or Walgreens, stay away from that stuff). But all in all vaping satisfies the nicotine the person needs with the inhaling of the vapor that mimics the sensation of smoke. "
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3m4dha | why are houses by the sea often more colorful than houses elsewhere? | At least here in the U.S., many homes near the coast seem to be painted with more vivid and varied colors than houses elsewhere. Is this just a matter of style, or is there some other reason for this? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3m4dha/eli5_why_are_houses_by_the_sea_often_more/ | {
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"Good question and I am no expert but i think the bright colors contribute to the whole \"island vibe\"",
"Saltwater is corrosive and the weather on the coast tends to be windy which combined with sand creates a sandblasting effect. So, houses on the coast need to be repainted more often. \n\nI suppose these people get tired of painting their houses the same color every time and if they paint a color they don't like it won't be long before they can try a new one. ",
" There is an old tradition of painting houses brightly enough that they can be identified from a boat. This way, a sailor coming back to town can see his home from a distance. "
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6jiooe | polynesian people look very different from east asian people, yet are hypothesized to have expanded out of east asia only a few thousand years ago. how have the come to look so strikingly different, so quickly? | People from Hawaii look extremely different from people from Taiwan, for example. Yet from what I read, Polynesian people were East Asian sea travelers who made land on the various Pacific islands. Why do they look so different from East Asians? How did they develop such different physical characteristics so quickly? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6jiooe/eli5_polynesian_people_look_very_different_from/ | {
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"Polynesians are thought to be descended from Taiwanese aborigines or Formosan people of Taiwan, which are a different ethnic group from the Han Chinese which mostly populate Taiwan today. ",
"Imagine you have an island with 5 brown haired people and 5 blond haired people. They decide to go voyaging to find a new island to colonize. 4 blond haired people and 1 brown haired leave and find a new island 500 miles away. Their island is now mostly blond haired people. The island that is left behind also now has shifted to mostly brown haired people. Even though the original population was a mix of the two.\n\nThis is called the founder effect. Polynesian people settled islands over great distances in canoes, so most islands had a relatively low starting population. This is how despite the fact that these people were all part of the austronesian expansion, you have some very distinct populations in the Pacific."
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amo0df | how come most (all?) mammals have separate liquid and solid waste disposal systems? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/amo0df/eli5_how_come_most_all_mammals_have_separate/ | {
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"One is for blood cleaning (kidneys make piss from it)\n\nThe other is food waste we dont take on.",
"Because the point of urine is only partially to get rid of urea. Mostly the point of it is to balance fluids and electrolytes. The kidneys have very finely tuned control over the amount of water lost. If they dumped into the bowels, the bowels would reabsorb a lot of the water, erasing the work of the kidneys. Additionally, it would make the kidneys more prone to infection, as your guts are teeming with bacteria. Lastly, diarrhea is no fun, and if you had integrated waste disposal systems, you'd constantly have diarrhea, increasing the amount of potentially harmful bacteria spread around the environment. \n\nLizards and birds don't have to worry about a lot of those issues, because they excrete solid uric acid, so they have an integrated waste disposal system. ",
"To the (all?)... Echidnas and other monotremes are mammals have a single opening called a cloaca, which they use to urinate, release their faeces and to mate. "
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1k9ktl | how iv fluid goes into our veins and ends up as pee | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1k9ktl/eli5_how_iv_fluid_goes_into_our_veins_and_ends_up/ | {
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"All of the organs in your body are connected by your blood. It's how the food that you eat can be sent to your muscles for fuel, how hormones released by your brain can cause your heart to race when you are scared, and how waste from your bodily processes ends up in your bladder. Waste products are released into your blood stream by most of the cells in your body and one of the main organs which filter these out are your kidneys. All of your blood will routinely pass through your kidneys and the specialized cells in your kidneys are able to differentiate toxins and waste products from helpful things like glucose and hormones. The helpful molecules remain in your blood while unwanted things are removed and sent to your bladder to be urinated.\n\nWhen you introduce fluids into your blood, like with an IV, these fluids will also go through your kidneys and will also be subject to filtration.",
"-First thing to understand: Drinking liquid goes into the same place as food. Into the digestive tract. Liquid is absorbed **into the bloodstream** through the side of the bowel...as is food.\n\n-Once liquid is in the bloodstream (IV fluid goes directly into the bloodstream) it is then filtered by the kidneys. What makes it through that filter goes from the kidney to the bladder, then comes out as pee.",
"All pee comes from your blood. Your [kidneys](_URL_0_) sit there filtering waste and water from your blood and pump that into your bladder.\n\nAlso all water you drink goes into your blood first before coming out as pee."
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38yl92 | why doesn't wind cause the air pollution in china to disperse? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/38yl92/eli5_why_doesnt_wind_cause_the_air_pollution_in/ | {
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"Because the sources of that air pollution are pumping it out faster than the wind can carry it away. There may also be some temperature inversions inhibiting sir movement, depending on the season and specific location."
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65cuf7 | why are some drugs absorbed through the gut, and some through intestine? | I have always wondered why, is there an explanation or the researchers just test it empirically to prove it is the way it is for some drugs?
If not, is it possible to predict which drugs will be absorbed in specific places (of course with some small deviation)?
Does it depend on the molecular structure of the drug or other things? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/65cuf7/eli5why_are_some_drugs_absorbed_through_the_gut/ | {
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"The location in the body at which a drug is absorbed is indeed dependent on its molecular structure. Some drugs can pass right through your cells and into the bloodstream, while others must pass through specialized proteins channels that allow them to make it through the cell to the bloodstream. You ask why certain drugs are absorbed in certain parts of the gastrointestinal tract. This is because each part of your G.I. tract has different types of cells, and these different types of cells have different types of receptors and channels on their surface through which drugs can act or pass. Therefore, what's happening in your stomach is going to be very different from what's happening in your terminal ileum.\n\nIt is also determined by how the drug is administered. For example, if a drug is given intravenously, then there is no absorption because it is directly administered to the bloodstream and has access to all of your cells. Other routes of drug in ministration include gastrointestinal, inhalation, and transdermal. Certain drugs will only be effective when given via certain routes.\n\nAbsorption can also be affected by how the drug is manufactured. For example, some pills have what's called an enteric coating. This prevents them from being absorbed in the stomach. They will therefore be broken down and absorbed later in the gastrointestinal tract."
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6zpu1s | why will the sun burn something through a magnifying glass but if the sun hits eye glasses it wont burn your eyes? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6zpu1s/eli5_why_will_the_sun_burn_something_through_a/ | {
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"Because glasses don't so much magnify as distort the light going through them to focus it where the eye needs it. You can create a heat spot with some lenses but you have to aim them directly at the sun and angle them just right so generally it's not an issue.",
"Actually, you can burn your eyes if you look at the sun for too long, whether or not you wear glasses. But you're probably asking a slightly different question, which is why don't glasses focus sunlight into a hot pinpoint the way a magnifying glass can? Mainly it's because your eyeglasses are designed to correct any distortion in your own eye's lens, which means they won't be focusing light into a tiny pinpoint; instead they will be changing it in whatever way compensates for the distortion in your eye."
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ctxsot | how do different shipping companies interact to ship goods worldwide? | Example : I order something from China EMS, they ship it to Canada Post which takes care of it. Who makes money here? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ctxsot/eli5_how_do_different_shipping_companies_interact/ | {
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"Your question is a huge one. The shipping industry is one of the most complex things in the world so I can only answer in part: about railways. \n\nDifferent rail companies in America have come together to track EVERYTHING in a common, central command. They gather all their telemetry and data streams into one place to have a consistent command and control over the entire continent's worth of railways. This is like a NASA mission control level of sophistication. \n\nIt's not that they make money by cooperating, it's that they avoid losing money by cooperating. Since they all invest in the information technology and they all get benefits from it, they can better avoid things like having important lines blocked (which costs millions or tens of millions of dollars per hour of downtime). \n\nI can only imagine that seagoing vessels and air freight companies do the same things for the same reasons. \n\nSource: I've interviewed/toured one of the railway control centers... Twice",
"Yes for the most part the railroads pay rent when on another's rails and in case of ocean lines will pay other companies for space on their ships if they don't have a ship going in the timeframes the person sending the stuff wants it done."
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3kaunz | how does the placebo effect work? if the body is capable of defeating a pathogen, why does it only do that when it is 'tricked'? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3kaunz/eli5_how_does_the_placebo_effect_work_if_the_body/ | {
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"its not that id only does that when your sick, its your brain that doesnt want to recognize youre getting better\n\nThe human brain is capable of many weird things, like making an amputaded arm hurt like hell even tho its not there\n\nPlacebos make you believe youre getting better, removing such obstacles\n\nIts a pretty deep and complex psychological response and summarizing a response here is hard"
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2siul8 | how movie committees choose which films make the nominations for oscars/bafta's and seem to ignore some of the big films of the year? | I was looking at the Oscar nomination lists and it seems that a few films such as The Grand Budapest Hotel, The Imitation Game, The Theory of Everything seem to be in many categories including best picture whereas big films such as Guardians of the Galaxy or Interstellar which have been praised are only nominated for things like Hair and Makeup or Visual Effects
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2siul8/eli5_how_movie_committees_choose_which_films_make/ | {
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"_URL_0_\n\n > The Sci-Fi Ghetto reflects a long-lasting stigma which has been applied towards the science fiction genre, which frequently leads creators and marketers to shun \"Sci-Fi\", \"Science Fiction\" or \"Fantasy\" labels as much as possible, even on shows that have clear science fiction or fantastical elements. It also reflects the tendency for critics, academics and other creators to near-automatically dismiss or disdain works which cannot escape this label being applied, regardless of relative quality or merit. Conversely, if these critics, creators and academics do feel that the work possesses merit by their standards, expect them to strenuously insist that the work is not science fiction or fantasy (How could it be? It's good), regardless of how many tortuous hoops they might have to jump through in order to do so.\n",
"It's largely political. Up until this past year, the nomination process for the Oscars was always done according to branch -- actors only nominated other actors, directors only nominated other directors, and so on. So, a writer would receive a ballot asking to nominate relevant categories, like, Best Screenplay, Best Picture, and Best Adapted Screenplay, for example. A writer couldn't vote for Best Actress or some unrelated category. The idea was that your peers should be your best judges -- how can a writer vote for best actor when they know nothing about being one? And they didn't want a director to only vote for actors in his/her movies and situations like that.\n\nHowever, this leads to voter abuse. As someone working in the film industry, you're much more inclined to vote for your good friend, partner, or peer as opposed to someone you personally dislike for whatever reason, even if they deserve to win. The nominating and voting process ends up being a popularity contest where friends vote for friends rather than a true critical, unbiased vote for the best of the best.\n\nThis year, they allowed all Academy members to vote on all categories (so, actors can vote for directors, writers, best picture, etc.) but only if they've actually seen all movies in the given category. Obviously there is still voting abuse, but overall I think it's a step in the right direction."
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6sr79n | why aren't "season tickets" to your favorite bands a thing? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6sr79n/eli5_why_arent_season_tickets_to_your_favorite/ | {
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"I can't speak for everywhere, but the bands I would subscribe too aren't in my area more than once a year, and when they are - it's part of a bigger concert.\n\nI would much prefer to just buy tickets on the fly, for flexibility and the economics of it."
]
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44ygua | if before the universe there was nothing, then the universe was created, shouldn't there be a field of nothing at the possible edge of the universe? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/44ygua/eli5_if_before_the_universe_there_was_nothing/ | {
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"There is no evidence that before the universe there was nothing. Everything we have ever observed or studied is part of the universe. There is no reason to believe that the universe *was* created, or that there even was a *before*, considering that time itself is a property *of the universe*.",
"The most widely accepted models of the universe do not have an edge. The universe is thought to be infinite in extent. The idea that it is \"material\" expanding into \"nothingness\" is a common misconception, fueled in part by the image 'big bang' calls to mind (an explosion). Rather, the evolution of the universe is thought to be one of an infinity, gradually declining in density.\n\n\"Before the universe\" is not known to be a coherent concept. Time is part of the universe, so it may make no sense at all to define a 'before' and even if we do, we don't know what form that \"Before\" took. It could have been raging panda parties for all we know.",
" Absolutely!\n\n What's important here is that we understand the usage of the word \"nothing\" in this context. We commonly use \"nothing\" as an explanation when we don't observe or don't know what a space contains. \n\nFor example, If we look into a closet and don't observe anything in it then we can claim there's nothing there. However, there's light in the closet and there's air in the closet, which is something that we just failed to observe when we made the initial observation and statement of \"nothing\" being in there. \n\nSo yeah, there's \"nothing\" at the boundary of the universe because we can't observe outside it and don't know what might be there.. \n\nSo nothing can be, and normally is something.. We just don't know what that nothing, or something, is until we observe it. \n",
"There is no edge of the universe.\n\nUniverse is infinite. Visible universe is finite which is different.\n\nLet me do an example.\n\nYou are blind and with other infinite blind people you are on a infinite line, one of you every 800 m.\n\nThen simultaneously all of you shout \"big bang\"!\n\nYou are blind, you can't see the others, but you can hear them.\n\nAnd every second you'll hear 2 people (one left and one right).\n\nAt first second the ones 800 m from you, at 2nd the ones 1600 m from you and so on.\n\nSo: there are people behind your udible horizon, just you can't hear them yet.\n\nNote that everyone on the line will feel the same effect, thinking he is the center of the line (universe), but he is not.\n\n",
"A common misconception about the expansion of the universe is to imagine it's expanding in all directions in three dimensions. You envision a balloon that we're inside. The balloon is getting bigger, and you say 'there must be an actual balloon around this space'.\n\nIn reality, the universe as we know it *is* the surface of that balloon. The balloon is expanding into the fourth dimension. Like two dots on an inflating balloon, any two objects in the universe that aren't locked together are getting farther and farther apart. The speed of this separation is always proportional to the distance between the dots, with more distant dots moving away faster. Space is essentially being created everywhere at once, from our perspective.\n\nBecause of these observations, we know that the universe is expanding in the 4th dimension. But we have no idea what that looks like beyond that. Maybe, somewhere, not up, not forward, not left or right, but some fourth direction perpendicular to all of these there is a great wall of the universe. But we can't see it.\n\nIn the three dimensions we perceive and move in, the universe is boundless, like the surface of a ball."
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78dy99 | how schools choose their curriculum? | I was always curious as to how certain classes got picked but others were not.
Why do we learn the poems of a guy who died 400 years ago, over financial and tax systems. Why do we learn trigonometry over statistics. That sort of stuff.
Edit:
High schools and lower preferred. But higher education as well. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/78dy99/eli5_how_schools_choose_their_curriculum/ | {
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"In some countries, it is dictated by law what subjects must be touched upon. These laws are created under the advisement of a national school board, consulting experts, etc.\n\nEach school is then free to choose their own classes and class content within the confines of these national laws/guidelines. Certain hours must be put into certain subjects, and certain knowledge of those subjects must be taught.\n\nInspectors may investigate schools were the results are not as good as expected, and they may issue an order for the school to adjust its curriculum to better adhere to the law."
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2igkkd | the supreme court chose not to take up the cases on gay marriage. if the 6th circuit court upholds bans in ky, oh, tn and fl, what happens now? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2igkkd/eli5_the_supreme_court_chose_not_to_take_up_the/ | {
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"They may reconsider taking up the issue next term. There are no current splits so the Supreme Court prefers to let it play out in the lower courts until that becomes a bigger issue. They do not want to take the flack for cowardly politicians, who are trying to pass the issue to them."
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3b7y16 | when a plane turns in the air why don't things slide? | I've been wondering.. I can see the plane turning and doing a diagonal motion but the water on my tray or the food stays in position.. It doest start to slide.. What is the logic begins this? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3b7y16/eli5_when_a_plane_turns_in_the_air_why_dont/ | {
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"This is called a coordinated turn. The pilot (or autopilot) controls the angle of the wings to balance the plane through the turn, like you would do while riding a bike. It makes for a more pleasant ride. The net force of gravity plus the turn is straight out the bottom of the plane, just not towards the center of the Earth."
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4zk6r5 | if there's only so much gold available in the world, why does goldschlager and edible gold flakes for baked goods exist. aren't we depleting our supply? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4zk6r5/eli5_if_theres_only_so_much_gold_available_in_the/ | {
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"Are you asking why aren't there laws that make it illegal for private use/ownership of gold?\n\nI'd point out, there's only so much of *anything* in the world. Land, iron, food, water, anything.",
"You can't digest gold so when you eat gold, you'll poop it out and it eventually returns to our supply.",
"Gold is a finite resource on the Earth, but since not all gold resources are equally recoverable, we can think of the supply as infinite on a practical level since the price will just increase based on the diminishing recoverable supply.\n\nFossil fuels also work on this principle.",
"The amount of gold in edible uses is so miniscule as to not matter. One of gold's properties is that it can be pounded out super thin so things like use in Goldschlager or even when gold leaf is applied to a dome it's only molecules thick. An entire capitol dome covered in real gold leaf may only use like 2 lbs of gold.",
"Gold is super malleable, so that gold leaf is amazingly thin. 7000 sheets of gold leaf are the thickness of a dime.\n\nHere's a site with gold fun facts:\n_URL_0_\n\nAs others have said, it's expensive more because we use it as currency than because it's rare.",
"I'm surprised that no one has really mentioned the fact that gold in and of itself has little pratical purpose in our current world.\n\nIt is a good conductor but is generally too soft for widespread usage as a conductor. Although as gold is resistant to many acids and other environmental impacts, when anti-corrision and conductivity is called for it can find a use. Only about 10% of gold mined now is used for this purpose.\n\nMost gold is used almost exclusively for jewlery, both for it's natural brilliance and it's acid resistance.\n\nThe other major use for gold is, frankly making gold bars for the purpose of investing.\n\nThe amount being used in edible products is a tiny amount compared to what we are otherwise using, so for every gold leaf covered cake we mine well more than that in a day.",
"There is only so much *everything* in the world, including the glass that Goldschlager is made of. The flakes of gold in Goldschlager are paper thin and worth like 13 cents. You can't digest it so you poop it out and it will be caught in a sewer filter someday. It's not like eating it makes it disappear from existence. Even if it did, all the Goldschlager combined is a minute amount of gold.",
"We're also using up our limited supply of helium in balloons. Nobody's getting rid of those either.",
"What goes in, goes out. Is will be send down the toilet into the sewers where it is filtered out and sold.",
"Oh good an economics question! This question has levels though.\n\nLEVEL 1\n\nThe reason why this happens is do to supply and demand. If it costs X dollars to consume Y, and someone is willing to pay more than X to consume Y, then eventually eventually someone in the market will provide that person with Y. And the more they are willing to pay for Y, the faster someone will pop up to provide Y.\n\nIt is very clear that there are people more than willing to pay more money to eat some gold than the cost of buying the gold and putting it some food.\n\nNow every time someone eats some gold and flushes the poop down the toliet, there is a little less gold available. And as a consequence the cost will go up. So every bottle of Goldschlager consumed makes the next one a little more expensive to make. But as the cost of gold goes up, that is means that there is someone out there willing to pay more for gold and that means someone will be willing go dig up some more.\n\nGiven how little gold is actually eaten and how much new gold is being brought into circulation because of improving mining technology, the actual consumption of gold has little effect on its price. But in theory, you are correct that the gold will eventually run out in a free market.\n\n------------\n\nLEVEL 2\n\nHere we kind of leave economics and go a little into psychology.\n\nAt level 1 we just acknowledged that some humans want to eat gold and they are willing to pay more for this than the cost of providing them some gold to eat.\n\nThe reason people are want to eat gold boils down to two reasons:\n\n1) Status: \n\nWhat you consume signals to others your status. If you see someone eating cheap ramen noodles, it signals to you that they are probably poor. When you drink beer it signals that you blue collar. When you own a hybrid it signals that are an environmentalist. When you own an antique it signals you are knowledgeable of history. When you eat gold it signals to others that you are wealthy and important. \n\nAnd when people assign a certain status to you, it can make desirable interactions more possible. If I collect rare antiquities, I may find it easier to join historical reenactment club. I eat Goldschlager I may find it easier to seduce that slut on the other side of the club.\n\n2) Identity:\n\nIdentity is very important to people. We all like to imagine who want to be and then behave in way that fits within that role we wish to adopt. \n\nIf I want to be rich, pretentious asshole, then eating some gold helps me to feel like am what I think I am. And eating some 50 cent ramen is going to have opposite effect.\n\n\n",
"Your average wedding band contains about 500 Goldschlager bottles' worth of gold. The *real* waste of gold in society comes when people are buried with their jewelry.\n\nAnd the US mines approx. 17,692,307,692 bottes' worth of gold every year. It's spit on a river.",
"It's gold leaf. AFAIK, gold is the most malleable metal known to man so it can be pressed extremely thin- to the point of translucency even. So a small amount of gold can be thinned out to produce a huge amount of gold leaf.",
"Don't see it mentioned, but the amount of gold used in the products you mentioned is an insanely small amount and will absolutely never meaningfully affect the global reserve. You might have heard a thumbnail sized piece of gold can be flattened to cover the area of a tennis court? Think of the infinitesimal amount used in a gold Schlager bottle, and why no one is taking bottles of it to cash 4 gold.",
"Because our gold supply is not limited. There is more in the ground left to be mined than we have ever extracted. There is a gold mine near me that produces over 7 tons of gold per year.\n\n_URL_0_",
"I've wondered the same thing, but not just for food. I wonder why we use rare, precious metals like that for *anything* other than something practical, preferably a scientific endeavor (gold foil for radiation shielding on satellites, for example). But, that's humans for ya. We are apparently poor at resource management if that resource can make some stupid consumer product more shiny.",
"Yes it is, but that is how capitalism works. Goldschlager paid for the gold, so they can do whatever they want with it. "
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65inca | why can men keep producing children in old age but women have the menopause? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/65inca/eli5_why_can_men_keep_producing_children_in_old/ | {
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"As women get older it becomes increasingly likely that there will be complications prior to and during child birth. In evolutionary terms it's better for the species to only allow child birth during a short window. For a male it doesnt matter as they aren't carrying the child so it doesn't really matter. ",
"We actually don't know. We don't know why human woman experience menopause. It's a somewhat rare phenomenon in the animal kingdom too. While there are a couple of other species that also experience menopause (non-human primates, elephants, whales) it is not a common thing.\n\nOf course we got a couple of hypothesises, but nothing has been satisfactorily proven.\n\nOn the non-adaptive front, there is the hypothesis that menopause is not something specifically selected for but rather just a side effect. Biologically, pregnancy requires a lot of high cost investment from females (more than from males) and it is simply harder to keep that up in late age.\n\nOn the adaptive front, there are several hypotheses that menopause was something specifically selected for evolutionary. \n\nOne of which is the mother hypothesis, which pretty much argues that because of the high cost of pregnancy at later age, and the higher chance of those children having defects, mothers improve the chances of their existing offspring (and thereby their genes being passed on) by being able to focus on them rather than focus on producing more kids.\n\nAnother one is the grandmother hypothesis, which is similar in some ways to the mother hypothesis, but argues that menopause in women was selected for because older women can improve the chances of not just their children, but their grandchildren as well, again improving the chances of their genes being carried on. The reason why this results in female infertility (but not male infertility) is because biologically a woman will always know who her child / grandchildren are, while males could not have this certainty. So for males it would continue to be beneficial to try and conceive more children, also at late ages. ",
"Something many people don't realize is that even though men keep producing new sperm into their old age, that doesn't mean that they're fine. The organs that produce the sperm have aged and this effects the sperm in negative ways genetically, as in chromosomal damage. So, at least women STOP making humans when their reproductive organs have aged beyond a certain point and genetic damage may occur. It's also known now that many birth defects can originate with the male through their sperm.\n_URL_0_"
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7lzsmw | why do parents work so hard to manage the sleep of young children (and is there an alternative)? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7lzsmw/eli5_why_do_parents_work_so_hard_to_manage_the/ | {
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"These parents are often exhausted and would really, really like to get more rest. That's why they are so keen on having their child sleep.",
"Yes, the child will eventually run out of batteries and collapse from sheer exhaustion. The trouble is that they’re often downright *demonic* while you wait for that to happen. They don’t just hang around politely waiting to drop off. Overtired children who need to sleep (but aren’t quite there yet) will scream, and cry, and fight you on everything. An hour of inconsolable screeching is not your idea of a good time, right?\n\nPlus, there’s the small matter that if they go to sleep at weird times, they can then *wake up* at weird times. You want a visitor at four in the morning?\n\nLittle kids don’t initially know that night time is for sleeping. This is something they have to be taught. For a lot of families, the easiest way to teach “this time is for sleep” is to set a consistent, predictable routine - when your show is over, you go and put your PJs on, and you do your teeth, and Daddy comes to read you a story and that’s it. Once all of those things are done, you’re finished for the night. You’re quiet, you’re in your own bed...even if you’re not actually asleep, that’s night-night time.\n\nIf there’s a disruption to that routine, that makes the lesson about “when to sleep” more difficult than it has to be."
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a0wwr4 | i found this mentioned on /r/science, can someone explain what "'twisted' light" is? | Thanks if you can! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a0wwr4/eli5_i_found_this_mentioned_on_rscience_can/ | {
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"I haven't seen the post but from what I can guess from the name they are using circular polarised light. And the way this is interesting is that you can encode more information.\n\nLets say that you see a photon, this is the equivalent of 1 in binary. The lack of a photon is 0. But now with circular polarised light you can have a photon with right and left hand polarisation. We can assign this two new values. (say 3 and 4). So effectively we have encoded more information into a single photon.\n\n",
"First you have to understand polarization, which unfortunately is pretty hefty for a five year old.\n\nLight has wave-like properties when it travels, and one of those properties is which direction the wave oscillates in.\n\nLike a wave on the water, there's a real physical \"peak\" and \"valley\" to the wave. As it moves forward, the wave is moving up and down, or side to side, or some combination of the two.\n\nUsually, the up and down and side to side move together, creating a flat plane of a wave. This has important ramifications, since the wave can't \"fit\" through narrow gaps if it's not aligned correctly. Polarized sunglasses use a screen that's badly misaligned with reflection from the ground to block sun glare. They're moving side to side and your screen is up and down, the wave can't fit.\n\nBut what if the up-down and side-side motion of the wave *isn't* in sync? Rather than knifing through space, now you're moving up, then to the side, then down, then back across. It's effectively a circle.\n\nThis is called \"circular polarization,\" and arises when the X and Y axis motion is out of phase. The wave is tracing a spiral through space as it moves instead of a randomly oriented plane."
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5c0baw | when animals are fighting, why do they sometimes pause in the middle of the fight and stare into empty space? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5c0baw/eli5_when_animals_are_fighting_why_do_they/ | {
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"They're trying not to get hurt. Animals fight for their lives and any injury could essentially be a death sentence.\n\nMore than likely they're considering escaping the situation but don't want to make themselves vulnerable.\n\nThat or they're dazed/tired and need a second to get their bearings.\n\nEdit: that flip kick to the head at about 1:15 was wicked though.\n\nAlso, I could word that better as animals don't ONLY fight for their lives.\n\nAny time an animal engages in a fight, they are essentially fighting for their life as any minor injury could result in an infection and death.",
"They're not staring into empty space. They're using their peripheral vision.\n\nTheir, and your, peripheral vision is more effective at seeing movement. \n",
"It's going to be hard to get an objective answer to this question since none of us can ask an animal but most fights are prefaced with a lot of posturing and displays of strength. When opponents are unevenly matched a fight is more likely to be avoided which benefits both animals since they risk injury if they actually fought. \n\nIf they are more evenly matched then it might result in a fight or if one of them feels cornered or defensive a fight is more likely but once the fight begins, both animals are seeking to win and any chance to end the fight without risk of further injury is a benefit. So after trading a few blows it's not uncommon for a pause while they re-evaluate each other and if their opponent is more capable than they thought they might break off the fight. \n\n",
"The same reason two knights would stop in the middle of a swordfight, or when two boxers suddenly pause in between heavy exchanges. To recuperate, while studying the opponent's position, movement, pattern, etc.",
"They may be considering whether or not the fight has come to a conclusion... essentially taking stock of their foe and their own situation. Remember, most non-predatory fights among animals are not intended to kill outright, just dominate. In essence, it could be a sort of, \"Are you fucking done yet?!\" moment. "
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30wlmm | why do i need to press ctrl alt delete before i can use my school's computer? | It doesn't really seem like a security feature, since if a hacker could enter a username and password, they wouldn't have problems with a button combination. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/30wlmm/eli5_why_do_i_need_to_press_ctrl_alt_delete/ | {
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"It's a security feature to make sure that you're typing your password into the real login screen, and the last person to use the machine didn't leave it running a fake login screen to collect people's passwords.\n\nFor historical reasons, the Ctrl-Alt-Del combination can only be read by Windows, it will never pass that keypress to any other program (in the days of DOS, it was used to reboot the computer). Therefore, if you press Ctrl-Alt-Del and something happens, you know you're dealing with the real Windows screen.\n\nActually it's not quite a guarantee now, since it's possible to give Windows some custom code to handle the login process so that things like fingerprint authentication can work. Installing a malicious version of that code to steal passwords would be much harder than just faking the whole login screen, though."
]
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|
1z4gyh | pain threshold. is it a real thing? what exactly is it? | What exactly is a persons pain threshold? Is it an actual physical thing or is it just in our heads? Can it be measured? Can it be increased? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1z4gyh/eli5_pain_threshold_is_it_a_real_thing_what/ | {
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"A pain threshold is the point at which pain is felt. As an example I grab your arm and start squeezing. At first you feel pressure and that increases. At some point you will begin to feel pain. That is the threshold of pain. \n\nIt can be increased. Swear. For men have a female present. Medication. "
]
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[]
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|
blqg45 | what's the difference between a samsung "fast charging" plug and a standard iphone one? is there any science to it or is samsung just trying to shoehorn my money into their pockets by limiting the amount of power its consuming? | Title says it, I have to lug around this bulky plug anywhere I want to have my phone charge faster than 22 hours for a full charge, while my girlfriend can plug her iPhone into pretty much any usb. Is there science behind it? Because it seems like the power source is the same. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/blqg45/eli5_whats_the_difference_between_a_samsung_fast/ | {
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"The power sources are not necessarily the same. Yes, they'll all provide 5V over the USB connection, but phone chargers are often limited to 1 Amp of current \"draw\" and tablet chargers/\"fast\" chargers will allow current and voltatges above the USB specification. The most common is 5V @ 2.1Amps, but the Samsung ones can take it up to 15V @ 2.1Amps. Look around, you should be able to find a reasonably sized charging plug (wall power - > USB) that will output 2.1 Amps. That should functionally be identical to a Samsung Fast Charger.",
"USB power standards used to limit the output to 5V and .5 amps, which gets you 2.5 watts. Newer standards allow for 2.1 amps/5V, or 10.5 watts, but your device needed to short the data lines for the power supply to allow that current draw.\n\nFor a few years, all of my Samsung chargers can supply 9V/1.65 amps, for fifteen watts. That would charge any supporting phone very quickly.\n\nApple chargers have a similar extra power mode.\n\nUSB standards are changing to include more power. USB-C cables plugged into compatible ports, can support 20V/5A supplies.",
"iPhone chargers put out 5W of power. But you can buy a power brick sold separately that puts out 18W of power so it charges faster.\n\nSamsung's power brick puts out 15W of power.\n\nRegular USB ports only give out 5W of power, so to the iPhone, that's normal power but to your Samsung, its regular charging and not fast charging",
"the S10+ battery is 4.1Ah. the XS is 2.6Ah. if you want them to charge in the same time the S10 will need a better charger"
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3k7k6q | how do so many average or even bad video games and movies consistently get so many high star ratings to display in their trailers and advertisements? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3k7k6q/eli5_how_do_so_many_average_or_even_bad_video/ | {
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"Any examples? In my experience, that doesn't really happen...",
"If enough people review you, you're almost bound to find *some*one who likes you enough to give a good enough review to use. Or you grab specific words from a review (\"The graphics are great\") and leave out others (\"but the gameplay is boring and uninspired\"). Sometimes reviews are based on incomplete information or even assumptions. Or you go to astroturfing or paid reviews or fake it some other way. \n\nIt's pretty rare to find something that has absolutely every single aspect of itself panned by everyone, so they just have to keep looking till they find something that's useful. "
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1c9gzm | why has the western world "forgiven" germany for wwii, but the eastern/asian world still hates japan? | What I mean by "forgiven" is that you **generally** don't see Western countries and its citizens holding contempt for and openly berating Germany for its WWII war crimes.
However, you still hear in the news about tensions between China and Japan that root back to WWII, and many Asians today still harbor deep hatred towards Japan.
Sincere or not, Japan has been issuing apology statements to various countries [since the 1950s](_URL_0_). Why can't the Asians just get along? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1c9gzm/eli5_why_has_the_western_world_forgiven_germany/ | {
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"Japan conquered Korea and parts of China *before* World War II. So even if they forgave everything during World War II, there would still be a lot of issues.",
"This is just my theory, but I think European countries are used to war in a different way than China for instance. I'm Dutch and we moved on after war with Spain, we moved on after war with Germany, we moved on after war with France, we moved on after war with England and we moved on after war with Belgium. We also fought together in wars with France, Germany and England only decades later. Would it not be easier for us to move on after war with Germany, compared to China and Japan who do not have this history? This is of course not the sole reason, but I do think it has influenced our judgement on past enemies or allies. ",
"You dont see angela merkel visiting a place where generals who did war crims are still honored. And thats not the only example, what is the point in apologing if the next week you say that comfort women never existed ? \n",
"Official apologies notwithstanding, Japanese public school curricula have a tendency to [whitewash Japan's role in World War II](_URL_0_) in a way the Germans haven't. High-ranking German public figures wouldn't be caught dead at a shrine for Nazi war criminals; [Junichiro Koizumi paid his respects at the Yasukuni shrine every year of his PMship](_URL_1_).\n\nThere's also the fact that various Japanese officials have had an on-again, off-again denialism about the scope of Japanese atrocities; PM Shinzo Abe, as late as 2007, [denied that the Japanese government had ever kept sex slaves](_URL_2_). It caused a fuss, and the government scrambled to apologize, etc., but you just don't hear that kind of equivocation from Germans about Nazi war crimes.\n\nAlso, racial tensions between the combatants in the Pacific theater were different--the Germans didn't view the French and English as \"inferior\" in the same way that the Japanese viewed the Chinese and Koreans, so they treated conquered populations differently. The most despicable of Nazi atrocities were committed, from the Allied perspective, against a sort of \"third party\" to the conflict (Jews, gypsies, dissidents, etc.); and it's always easier to forgive on behalf of someone else.\n\nThe Chinese and Koreans were the direct targets of Japanese atrocities, including war rape, medical experimentation, slavery, and genocide. Someone gets drunk and beats his wife, it's disgusting; but someone gets drunk and beats *your* wife, that's a whole different story. Their bitterness toward the Japanese isn't all that different from Israeli attitudes toward the Nazis.\n\n**TL;DR Japanese officials' attitude toward their history has been rather more ambivalent than their neighbors would like, and the racial component of the conflict was very different.**",
"There are many factors that would cause that tension to still exist. \n\n1. Historically, China and Japan always hated each other. In the 19th century (and even later), they would constantly compete for economic dominance. The Sino-Japanese Wars also didnt help.\n\n2. The Rape of Nanjing. To many Chinese, this event is still identified as exemplifying the Japanese's cruelty and ruthlessness. And although there may have been some apology statements, many public officials in Japan continue to deny the event. They believe that a huge and bloody massacre--which took 250,000 to 300,000--is just made up. Some of these in denial include the Tokyo governor Shintaro Ishihara and Takashi Kawamura, mayor of Nagoya.\n\n3. The conflict over the Diaoyu/Senkaku Islands has recently reignited some pre-existing tensions and they hate each other with a passion again.",
"I think the main jist of it is how POWs were treated. Captured Chinese soldiers and civilians were often tortured and/or executed. The Koreans were living under Japanese rule for many years beforehand.\n\nThe Germans did not do nearly the same things to US, UK, and French POWs they captured. However, they **did** horrifically mistreat the Soviet POWs, who did the same right back. As a result, Russia has a similar attitude towards the Germans as the Koreans and Chinese have towards the Japanese."
]
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"http://en.wikipedia.org/wiki/Comfort_women#Apologies_and_compensation"
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aa45le | what allows modern thermometers (for measuring body temperature) to get a reading so much quicker than the older mercury in-mouth thermometers? | For example, nowadays in-ear thermometers and no-touch forehead thermometers are pretty common, can be bought for like $25, and give a (more or less) accurate reading in seconds whereas old in-mouth under-tongue thermometers used to take minutes.
I guess, specifically, what's the technology that allows this? Is it infrared? And was this technology simply too expensive to produce for wide retail distribution ten, twenty years ago? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/aa45le/eli5_what_allows_modern_thermometers_for/ | {
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"It is infrared imaging technology, and there are a number of elements that have come down in price to make this technology meet the consumer price point. But it's really the push to eliminate the danger of glass thermometers that had lead to the change.\n\nBasically, these thermometers focus IR radiation from your ear onto a photodiode, measure the diode current, and convert it to a digital readout.\n\nThe electronics and display have been cheap as long as calculators have been cheap. Lenses these days can be computer designed and stamped out of plastic, so they're cheap as dirt. Photodiodes have come down in price thanks to fiber communications networks.\n\nAll the elements have been around for a long time, and relatively cheap IR thermometers could have been made 10 or 20 years ago. Today it's cheaper than ever because of the ongoing electronics revolution, but that's not the driver. \n\nIt's that mercury used in some glass thermometers is a toxic heavy metal. And even the glass alcohol thermometers present the risk that the glass might break. Since fever thermometers are used mainly on children, the risk of having a broken shard of glass in a child's mouth is one we all want to eliminate.\n\n & #x200B;"
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6zr06v | how is lossless compression so good? (detailed) | To start off, yes, I know how it works, I know how specialized algorithms can do amazing things with ratios of 25% sometimes when time is not a concern.
What I am asking is how it can get below 100% ratio in every situation that you would use it for.
The reason why this is confusing for me is because I was thinking and I came up with a formula for testing how likely your file is going to be compressible.
Example: Say you wanted to compress a set of 8 bits to 7 bits. 8 bits can represent 256 DIFFERENT values, while 7 bits can only represent 128 values. So that means that half of the files are IMPOSSIBLE to compress, even with 1GB files.
So the formula that I made to see how likely your file is to compress is: **1/2^How-Many-Bits-You-Want-To-Compress **
**Now the question: ** How can 7-zip and other apps compress by multiples of mega-bytes when the chances of it being able to are astronomically high?
*(This is a shower thought, let me know if I'm forgetting something.)* | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6zr06v/eli5_how_is_lossless_compression_so_good_detailed/ | {
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" > Example: Say you wanted to compress a set of 8 bits to 7 bits. 8 bits can represent 256 DIFFERENT values, while 7 bits can only represent 128 values. So that means that half of the files are IMPOSSIBLE to compress, even with 1GB files.\n\nThe thing to remember is that the vast majority of \"all possible files\" are just garbage data that don't mean anything. Not every single possible arrangement of 1 gigabyte of data has any meaning. And files that actually mean things tend to have a lot of repetitive data that make them prone to compression.\n\nThat said, you *are* right in realizing that not all files can be compressed. This generally crops up when someone tries to compress an already-compressed file. They will actually make the file *bigger*.",
" > Say you wanted to compress a set of 8 bits to 7 bits. 8 bits can represent 256 DIFFERENT values, while 7 bits can only represent 128 values. So that means that half of the files are IMPOSSIBLE to compress, even with 1GB files.\n\nYou are absolutely correct, and this is the basic proof that not all files can be compressed by a given algorithm. Be proud you understand it, the professor who taught my data compression class did not. \n\nAnd it is even worse than that. Of the half that can be compressed, half can only be compressed by one bit. Have of what remain can only be compressed two bits, etc., etc. Only the tiniest fraction can be compressed to any significant degree.\n\nHow can we compress anything? Because even a tinier fraction is going to be anything we would ever want to compress. \n\nThere are about [36,000](_URL_0_) ten letter words in English, from aardwolves to zymometers. But there are 141 million billion possible combinations, meaning 99.99999997% of them are gibberish. And thats just 10 letters, the longer you get, the lower the sense/nonsense ratio gets.\n\nKeeping that in mind, the chances of finding compressible data isn't nearly as astronomical as you might think.\n\n\n\n"
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e1w2td | internet cookies and what happens if i don’t enable them? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/e1w2td/eli5_internet_cookies_and_what_happens_if_i_dont/ | {
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"A cookie is a piece of data that a website can ask your browser to store. Whenever you visit any page in the website, your browser will automatically send this data back to the site.\n\nCookies are used for storing information about you. For example the first time you enter a website it often generates a random cookie value known as a \"session id\" which can then be used by the website to remember who you are.\n\nOn the other hand, cookies are also used for tracking purposes - if a website contains an ad, then the ad might inject a cookie that can be used to track you across multiple websites, so they know what sites you visited.\n\nDisabling cookies will hurt your experience in heavily used websites - they won't be able to store any info about you, so they won't be able to remember who you are and what your settings are. However if you're just visiting a website that one time, or you just use it for reading content statically, then cookies aren't that important.",
"Cookies are simply small text files that your computer stores on behalf of a website so that the website can store data between your visits or know who you are. Things like your configurations in an online solitaire, your login credentials, your user ID so that Amazon can show you the correct shopping cart, e.t.c. \n\nIf you do not enable them what happens depends entirely on the website. Most websites will have a hard time proving you their service: you can't log in anywhere because your browser can't prove that it just logged in anymore. Any saved data or configurations vanish the next time you change the page. Websites will no longer be able to recognize you, and so on and so forth."
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7uw4a3 | compared to talking in person, why can two people talk normally on the phone but video chatting is so awkward and interrupting each other? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7uw4a3/eli5_compared_to_talking_in_person_why_can_two/ | {
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"Body language might be a factor. When you are sitting face to face with a person, subtle clues about how they are feeling, or what they are intending to do may be more visible. For example, you may see and hear someone take a big inhale when they prepare to begin speaking, but on a webcam you may miss this detail. ",
"With video chatting I’ve noticed a very slight delay/lag sometimes. It’s easier to accidentally interrupt the other person if you thought you were speaking into silence... but they had actually already started talking, it just didn’t make it through the lag fast enough."
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7lo4r5 | how is concrete poured/set underwater when making bridges? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7lo4r5/eli5_how_is_concrete_pouredset_underwater_when/ | {
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"When they can or are required to, they remove the water from the area by putting down something around the intended concrete volume to keep the water out, essentially like a \"moat of air\" that's either open on top or fully sealed. [It's called a cofferdam if open](_URL_0_). \n\nWhen they can't or it's not cost-effective to do that, they can use underwater concrete, which is usually poured via pipe into prebuilt forms. The heavier concrete displaces the water as it fills the form. \n\nIn many bridges, particularly ones that cross deep water, they manufacture the posts and stands for the bridge elsewhere and move them to their locations. Requires some pretty damn big transports to do this though. [Here's how the parts look for the \"Confederation Bridge\" which connects Prince Edward Island across 12 kilometers of the Atlantic Ocean to New Brunswick in Canada.](_URL_1_) I saw some of this in action and it was pretty impressive engineering.\n\nWhen the conditions are right, for some really big projects like dams, for example, they divert rivers to other areas until the structure is ready."
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2yjnty | if the half-life of the fuel is so long, why do nuclear power plants need to be refuelled? | Surely the fuel will keep releasing energy? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2yjnty/eli5_if_the_halflife_of_the_fuel_is_so_long_why/ | {
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"Nuclear engineer here. You are confusing radiation with fission. They are two different things. \n\nWhen we split the atom, we take a fissile fuel material like uranium-235, and we split the atom. Once it is split, it becomes smaller atoms which are not capable of a nuclear chain reaction(in fact, the waste products actually disrupt the nuclear reaction). \n\nThere are three reasons we need to replace the fuel rods. First, we do actually use most of the fuel in them. When we take fuel out, roughly 85-90% of the uranium 235 is gone (this is the actual fuel, and when we split it and it became something different). \n\nSecond, the waste products that build up in the fuel actually inhibit the nuclear reaction in the core and will prevent it from staying at full power, so we want to pull the oldest fuel out and replace it with fresh fuel. \n\nThe third is that the longer the fuel rods are in the reactor, the weaker the rod cladding becomes. After 3-4 years in the reactor, a fuel rod can only safely produce about 30% of its original heat output without breaking. \n\n"
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5vt2n7 | if hipothetically around the world, we all lower 10% of the cost of everything, will we effectively lower 10% of global inflation? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5vt2n7/eli5_if_hipothetically_around_the_world_we_all/ | {
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"text": [
"If you're changing salaries and savings too then you're effectively re-scaling the currency, which isn't the same as inflation. It's highly frowned upon because the logistics are nightmarish, but countries have done it occasionally when bouts of severe inflation left the old currency nearly useless. It doesn't actually address inflation because nothing has changed relative value.\n\nInflation changes future costs, but more importantly it *doesn't* change the dollar value of debt and savings. This devalues savings and debt since they're now comparatively lower in value.",
"Someone who studies economics might be able to tell you better. \n\nAs far as I know, the closes you can get to what you're suggesting is a currency conversion. \n\nA government could change currency and say, all US dollars are going to be replaced by U coins at a rate of $1 = 0.90 Ucoins. Then, tell everyone they have to trade their old dollar bills in for 0.90 Ucoins by X date. That wouldn't, in theory result in inflation since everything still costs the same proportional to everything else, you're just putting a different magic number on it. There might be some physiological adjustment that results in inflation or deflation, but that wouldn't exist in an economics experiment. \n\nOn the other hand, if the government simply printed 10% more money. They asked everyone to say how much money they have in their bank account, and then give them a check for 10%, but making more dollars. Then you would get inflation. I'm not sure if it would be 10%. There are a lot of variables. After all, the government has been printing tons of money as part of the QE program, and the inflation predicted never came about. That might have to do with how the money was injected into the system or maybe external global factors. "
]
} | [] | [] | [
[],
[]
] |
||
2r7cuy | why don't u.s.-based websites have a two letter code like the rest of the countries?(like .it for italia, .br for brazil, etc) | Explained | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2r7cuy/eli5_why_dont_usbased_websites_have_a_two_letter/ | {
"a_id": [
"cnd4902",
"cnd4kbl",
"cnd7r9x"
],
"score": [
3,
3,
2
],
"text": [
"com does not mean its US based website. if you are asking why some are .com and others are .it .br etc.",
"It used to be a reserved domain until \"recently,\" so companies turned to .com making it the unofficial domain of America. .us is available now and can be used (has been available for over a decade) but it's too late. .com already became the unofficial American domain.",
"There is a .us. Its just not used much other than by some gov organizations\n\n_URL_0_\n\n_URL_2_\n\n_URL_1_"
]
} | [] | [] | [
[],
[],
[
"http://www.revenue.state.il.us",
"Http://dnr.state.il.us",
"Http://ides.state.il.us"
]
] |
|
1e2ial | github. | Can someone explain to me what the purpose of github is, what it does, how to use it etc. Never done enough digging to truly understand and what I do find seems to be written for developers.
Thanks!
edit: spelling | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1e2ial/eli5_github/ | {
"a_id": [
"c9w5d86"
],
"score": [
5
],
"text": [
"Github is just a place to host git repositories. You could make your own such server, or even just keep a p2p version of git. Github gives a few advantages, but nothing you couldn't get from dropbox or just any other form of good backup. \n\nBut of course, maybe you don't know what a git repositories is. In which case this wouldn't be a good explanation. So I'll try to explain git to. \n\nGit is a version control software. And you really need that. Git allows you to look back through the history of your program to see what's been done (and who did what). If something breaks, you can go back and fine the the change that did it. If you really fuck up, you can just go back a version. You can create branches (which is a parallel program, so you can try out new experimental changes without being afraid of messing up something). It makes merging easier (you and I both work on the same program for a day. Then we need some way to put the two versions together, that's merging). \n\nSo in short it's 50% back ups and 50% \"fuck up\" avoidance. "
]
} | [] | [] | [
[]
] |
|
1ypxf3 | why do organic eggs have a lighter yolk than free run/barn eggs? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ypxf3/eli5_why_do_organic_eggs_have_a_lighter_yolk_than/ | {
"a_id": [
"cfmox98"
],
"score": [
3
],
"text": [
"Egg yolk color is controlled by the chicken's diet. Most of the orange/yellows come from carotenoids (like b-carotene) and xanthophylls. Not all of these have any nutritional value, but some (b-carotene) do. Intensively farmed chickens tend to have pretty rigorously controlled feeds with vitamin supplements designed to make those yolks a deep color (not that this means they are more nutritious, it depends on what they add to get that color). Organic eggs tend to come from chickens fed a less rigorous and supplemented diet, and as such vary a lot more in color, but don't usually attain the deep orange/yellow you get from chickens on a supplemented diet. "
]
} | [] | [] | [
[]
] |
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