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9f2v7g | how does glass work to help plants grow? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9f2v7g/eli5_how_does_glass_work_to_help_plants_grow/ | {
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"What do you mean?\n\nLike greenhouses? They let in light and trap heat, allowing plants to grow in colder climates than they could otherwise.",
"Greenhouse design and construction is a fairly detailed science on its own. It varies based on your altitude, your agroclimatic conditions etc.\n\nGlass is almost exclusively used in temperate countries which get frost or snow during winter which is harmful to plants that are not tolerant of such conditions (flowers, fruits etc).\n\nIn warmer climates, plastic is used instead of glass, with features like side screens and top vents designed to maximise air flow and reduce ambient temperature.\n\nThe objectives of using glass (or any other material) in protected cultivation are:\n\n1) provide more suitable growing temperature, humidity to the plants\n\n2) absorb UV radiation from the atmosphere and filter the light entering the greenhouse\n\n3) prevent entry of pests and airborne pathogens into the plants"
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22qlvb | why do red and blonde hair tend to run in the same families if there both recessive genes? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/22qlvb/eli5_why_do_red_and_blonde_hair_tend_to_run_in/ | {
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"I'm not entirely sure of the allele frequencies of red/blonde hair but I'll continue regardless. By allele frequency I mean the number of people in the population who carry the particular gene variant/allele e.g. blonde/red hair\n\nThey must be at sufficiently high frequency that homozygotes (people with two copies of the blonde/red allele who therefore have blonde/red hair) and heterozygotes (Individuals who have the recessive allele for red/blonde hair and another dominant allele for e.g. brown hair) interbreed. \n\nFrom this homozygote heterozygote pairing 50% of their children will be blonde/red head.\n\nThere is another factor which comes into play called Penetrance. This is kind of a difficult concept to grasp. We're used to thinking of a trait (e.g. hair colour) being coded for a single gene, of which there are multiple alleles (brown, red, blonde etc.). However, in reality most traits are encoded for by multiple genes which work together to produce the trait. Therefore genes which encode for specific traits (e.g. hair colour) can be highly penetrant i.e. if you have gene X you will get trait X, or have low penetrance i.e. if you have gene X, there is a lower chance you will exhibit train X due to the influence of multiple genes.\n\nSorry if this is a sucky, explanation, I'm tired. What i'm trying to say is that blonde/red hair alleles must be in the population in a sufficient frequency for people carrying these genes to mate often, and it must be highly penetrant.\n"
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1nkyiq | how does turning on a lightbulb use more electricity than keeping it running? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1nkyiq/eli5how_does_turning_on_a_lightbulb_use_more/ | {
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"There must be an initial surge of energy to get the filament to the proper temperature to produce the light. ",
"It all depends on how long you would be leaving it on for as opposed to possibly simply walking out and walking back in. MythBusters took this on!\n\n\n_URL_0_"
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bwz9km | how did columbus communicated with the aztecs if they didn’t speak their language and vise versa? | Edit* I meant Hernan Cortes not Columbus. I have failed my history teachers! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bwz9km/eli5_how_did_columbus_communicated_with_the/ | {
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"Columbus didn't communicate with the Aztecs. He never met them. \n\nHernan Cortes was the man responsible for destroying the Aztec empire. \n\nWhen Cortes first landed in the Yucatan he met Geronimo de Aguilar, a Spanish Franciscan priest who had survived a shipwreck followed by a period in captivity with the Maya. This priest had learned the Mayan language. \n\nLater, Cortes fought and beat the Tabasco natives. They gave him 20 women. One of which was called La Malinche and would become Cortes' mistress. She knew the Aztec language and the Mayan language, so Cortes was then able to communicate to Montezuma of the Aztecs through these translators."
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b9x26m | how integrals can calculate areas? | im new here so im sorry if this doesnt belong here, but this question is driving me crazy all the explanations i could find are pretty complex, im suppoused to imagine an infinite amount of squares or something like that? but than, how could it ever be accurate?
| explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b9x26m/eli5_how_integrals_can_calculate_areas/ | {
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"There is a 2d area underneath the curve of a function, or in between functions. There are also 3D volumes under and between curves, the x, y, and imaginary z axis. \n\nNow, when you want to find these curves you have to use a tool, which is the integral function. \n\nIntegrals can approximate area and volume, among other things. \n\nThe way that works is by creating infinite shapes of the same area, and including those under the curve in the final calculation and discarding the others using the FTC. \n\n\nAnd I can’t give you a better explanation because this is all I truly understand. ",
"How could anything less than ~~infinity~~ the limit as infinity is approached be accurate?\n\nOr, rather, to find the area under line f(x)=1 between 0 and 1, you could use as few subdivisions as you wanted and still find the accurate answer. But the magic of going to that limit is that it always becomes accurate unless it's a bullshit function without a describable area at all. Consider f(x)=x and your left-handed Riemann sums will always underestimate, and your right-hand sums always overestimate, unless you proceed to that limit and it becomes the accurate answer either way.\n\nIt sounds like you're still on the early chapters of integration, though. Just like with derivatives, you will first learn the ugly-if-truthful way the integration rules are found, after which you will simply memorize the already-ugly-derived rules which are much easier to make use of! So don't worry even if you kinda flunk this section, the next ones will be easier.\n\nThe integral of f(x)=x is\n\nThe integral of f(x) = x^(1) which is a power, so use the power rule: int(x^(n)) =(1/ (n+1))×x^(n+1) + *c*\n\nIt is F(x)=(1/2) × x^(2) + *c*",
" > how could it ever be accurate?\n\nAs you add more rectangles the closer you get to the true answer (because each rectangle will better approximate the curve). The more rectangles you add the closer the \"error\" is to zero. \n\nOnce you have an infinite number of them the error *is* zero. If you know what limits are it's quite literally the same thing. If every step has you get closer to reality, and you take an infinite number of steps, you'll get infinitely close to reality, which means you've arrived at the correct answer. "
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3u9lci | how does the same model of device get software updates at different times during a rollout? | When a company releases a software update, sometimes they "roll it out" over the course of a few days. How does it become available to one device on Day One and an identical device not until Day 3? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3u9lci/eli5how_does_the_same_model_of_device_get/ | {
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"Every device had a unique serial number. The device sends its serial number to the update server which uses it to decide whether the device gets an update. "
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3oc4ms | do "not for individual sale" warnings on products have any legal binding? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3oc4ms/eli5_do_not_for_individual_sale_warnings_on/ | {
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"The point of the label is that required legal statements (like nutrition and ingredients) aren't on the individually wrapped servings but rather on the box they came in. These warnings protect the manufacturer from charges that they made items without the required labeling.",
"If you look on each individual item they're usually missing a sell by date too therefore making them illegal to sell (that's how it works in France at least) ",
"Usually this means \"*not labelled* for individual sale,\" for example if nutrition facts are not disclosed. Private resale is usually still legal, because most laws about food sales only apply to commercial operations of a certain size.",
"I used to go to a little greasy spoon cafe for lunch, all of their drinks cans and crisps were multipack \"not for individual resale\". Noone cared, though they were closed down as they encroached on the business park canteen catchment area.\n\nI thought it was more to do with cost, a 50 pack box of crisps is £12 at a wholesaler, yet you can often get 6 packs for £1 at the supermarket, 8x6 is 48 packs for £8. Yes they're smaller (and 2 packs short), but its 50% difference."
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449bxo | why couldn't martin shkreli call the committee of congressmen imbeciles right at the hearing ? can he invoke his 5th amendment and still them to go take a hike? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/449bxo/eli5_why_couldnt_martin_shkreli_call_the/ | {
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"Just like contempt of court, you can be fined or jailed for contempt of congress.\n\nYou have to respect the proceedings even if you do not respect the people."
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4su7xl | why does a knife need to be moved to be sharp? if you touch a knife it's ok, but if you drag your finger down the edge it hurts. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4su7xl/eli5_why_does_a_knife_need_to_be_moved_to_be/ | {
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"Knives are still sharp straight-on and can cut that way. However, at a microscopic level, even straight-edged knives have tiny teeth. So when you move the edge against the item to be cut, you are actually running a tiny ultra-sharp saw across it.\n\n[Micro photo of a razor's edge can be seen here.](_URL_0_)",
"On the microscopic level, the edge of the blade is jagged. Same with your skin or just about any other surface. So when you pull on the blade, all those molecules rub up against each other, causing the hard metal molecules of the knife tear at the softer surface.",
"I have a follow-up question to tag along with this:\n\nLet's assume I have a blade that we've been able to sharpen away all the jagged edges all the way down to the atomic level. Will this knife cut the same way? ",
"Assuming you have a properly sharpened knife, the ability to cut anything is based on pressure - the same reason you can drag a utility knife through cardboard and it will cut instead of having to use a sawing motion. The ease of cutting depends on edge sharpness (defined by molecular structure and sharpening methods) and blade geometry - but that is for another day.\n\nOn a properly sharpened knife, you can cut quite a bit with relatively little to no pressure - you can drop a human a hair on the edge and the weight of the hair is enough for it to be severed in two. So technically, touching a knife (depending on how much pressure you put and how sharp the edge is), could cut you. In reality, most cuts from truly sharp knives are realized after the fact - they cut cleanly and blood doesn't appear for a split second or two.\n\nTL;DR Dull knives need sawing motions to cut things; properly sharpened knives can push cut.\n",
"A lot of wrong or incomplete answers here. Let me clear this up by explaining normal and shear stresses. \n\nA knife is sharp regardless, the issue is the way the stress (force per area) is applied. When you push down on a knife you are only putting normal stresses (that is to say, a force perpendicular to the surface of your skin over the cross sectional area of the knife edge) on your finger. When you drag the knife, in addition to these normal stresses you are also putting your skin under shear stress. Shear stress is the force per unit area that is parallel to the surface of your skin. \n\nWhen I say force per unit area, I mean something conventional like psi (pounds per square inch). However, you can imagine that at the very tip of the blade the surface area is extremely small. When the surface area is very small you exceed the strength per unit area (think of this as the force that can be applied over a region before it breaks) of your skin and you get cut. This is why a bullet can kill someone but something about 10x the size with the same energy might knock you out - the force per unit area is reduced even though the force is the same. \n\nNow you can visualize a needle, which has a very small surface area parallel to the surface of your skin - it looks like a tiny circle. It can poke you but you probably cant cut anyone like a knife with it because the cross sectional area (the view you would see if you were looking at the needle in 2D) perpendicular to the surface of your skin is much larger and rectangular. The normal stresses are very high but the shear stresses are not very large.\n\nIn short:\nA knife when slid across your skin applies forces both parallel and perpendicular to your skin AND the cross sectional area of the knife tip parallel to the surface of your skin is very small, increasing the shear stresses and cutting you.\n\nEDIT:\nhere is a picture of various cross sectional areas so you know what I mean. Without taking pictures or access to a cad program I cant make a good one. \n_URL_1_\n\n_URL_0_\n\nThe second picture is the cross sectional area you would see in shear.\nThe top picture is what you would see in normal stresses.",
"For the record if you have a sharp enough knife you can cut yourself on it by touching it, ie. without a sawing motion.\n\nHigh end carbon steel chef's knives do that pretty often. I'd assume things like obsidian scalpels would as well.",
"It depends on the knife. A very sharp knife can actually cut a handkerchief dropped on it. \n\nThe reason that slicing with a knife cuts better is because of the very small teeth of metal along it's very edge. Because of the structure of the metal, and the way it's sharpened, it doesn't create a smooth edge. There are tiny little burs and teeth that stick out from the edge unevenly and these are what do the cutting.\n\nWhen a knife starts to get dull and you see somebody use a chef's steel or a leather strop, it's not sharpening the knife by removing any material, instead it's taking the bent teeth on the very edge and standing them back up in the same direction. Then as you use the knife they will start to get bent again, dulling it. Eventually many will snap off, or become so bent they can't be bent back with stropping and this is when you need to actually sharpen the knife by removing material like with a stone or tool. \n\nNow the rougher and larger these little teeth or whiskers of metal on the edge are, the harder it is to begin the cutting motion. If you use a coarse stone you get coarse teeth. If you use a very smooth stone, and then you strop the blade with some rubbing compound, it creates a very smooth, polished edge with very small teeth that are more uniform in size and it makes it easier to cut. This is what puts a razor edge on a knife allowing it to shave hair off easily. \n\nThe very smoothest edges are so sharp that you do not need to slice or saw; simply touching the blade to something will begin to cut. \n\nThere are also different shapes of knife edges that give them different properties. A katana for instance has a rounded shape kind of like the pope's hat. This shape causes it to spread something as it cuts into it, reducing resistance and allowing the cutting edge to cut with less friction. This allows a katana to cut through very tough or thick material without slowing down much in a swing. \n\nContrast this with the edge of a scalpel which looks more like a V and allows for very fine cuts and a lot of control for very precise work like surgery. \n\n\n\n",
"As my mum explained to me when I was a kid, slicing is all about speed. \n\n\n\n\nRun fast enough, and you can get sliced by blades of grass. ",
"An expert knife maker can make a knife so sharp that it will cut you at the slightest touch."
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eo7a0t | as alcohol sterilizes stuff, when we drink booze it kills the good bacteria inside us? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/eo7a0t/eli5_as_alcohol_sterilizes_stuff_when_we_drink/ | {
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"Alcohol is absorbed in your small intestines and subsequently processed and broken down enzymatically by your liver long before it reaches your colon. The colon aka large intestines is where your gut bacteria live predominantly",
"Rubbing alcohol is like 60-80% in order to be effective. Drinking alcohol of 10% or less will have virtually no effect. Any amount you drink would be immediately diluted to no effect.",
"No, but it does prevent the drink from getting most bacteria, thats why on times when the waters could get dirty or poisoned often it was 'healthier' to drink wine.",
"Alcohol we drink is not concentrated enough to have a significant effect on mouth, gut, or blood bacteria. Even if you drink really strong spirits, by the time it gets through your stomach it has mixed with a lot of other fluid (and solid food) which heavily dilutes it. The only exception is mouthwash, which works on your mouth and throat, but that's not suitable for drinking."
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2x9dnc | how is it possible for something moving the speed of light to experience no time. | I was recently listening to star talk and Neil deGrasse Tyson noted that light is simultaneously at its starting point and its destination because something moving the speed of light experiences no time. I can't really get my head around this. We can measure the fact that it takes light 8 minutes to get from the Sun to the Earth. How can that 8 minutes be different from the perspective of the light? I would assume (wrongly I suppose) that increasing speed only changes the distance you travel in an amount of time and shouldn't change how much time you feel like that takes. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2x9dnc/eli5_how_is_it_possible_for_something_moving_the/ | {
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"The concept at play here is called Special Relativity; it's one of Einstein's greatest achievements.\n\nThe ELI5 is that time slows down for *all* moving objects. You don't notice this on a day to day basis because you're moving *really* slowly; you need to be moving at a nontrivial fraction of the speed of light for the effects to become noticeable.\n\nBut, for example, if you were to get in a spaceship and go at .99 times the speed of light and take a 1 lightyear trip that ended up back at Earth, we on Earth would have to wait a year for you to return, but it would only seem like about two months to you on the ship.",
"Yep, it's wrong. We like to think of velocity as being a simple thing. If you are going to a place X miles away, and you go x miles per hour, you get there in an hour. if you go x2, you get there in half an hour and so on.\n\nAt every day speeds, this works, because the difference is so small, you'd never notice it, even adding it up through an entire lifetime.\n\nBut at relativistic speeds, when you are moving a sizable fraction of the speed of light, this is no longer true.\n\n\n > shouldn't change how much time you feel like that takes.\n\nMore confusingly, it doesn't change how much time you *feel* it takes. To you, time is always 1 second, per 1 second. It *literally changes how fast your time moves* in comparison to that of some other frame of reference. \n\nTo you, one second per second will have passed for the entire trip. But to someone moving at a vastly different velocity, you will see their time as moving more slowly than your own. They, in return, will see your time as having moved more slowly than their own. \n\nA way I have tried in the past to visualize this:\n\nWe can observe that the speed of light in a vacuum is a constant, it moves at c for all observers. For simplicity, let's say c is 10 miles per hour.\n\nIf you shine a flash light beam so that one photon shoots out, you'll see it travel away from you at 10 miles per hour.\n\nIf bob is driving by in his car at 5 miles per hour, he also sees the photon traveling away from him at 10 miles per hour.\n\nSo after an hour, both you and bob see the photon as 10 miles ahead. but bob was moving past you at 5 miles per hour, so he's 5 miles ahead of you. So his photon, 10 miles ahead of him, is 15 miles ahead of you. \n\nHow can one photon be in two places at once? It can't.\n\nWhen your wristwatch says an hour has passed, you can see Bob's dashboard clock has only registered half an hour, so to you the photon is 10 miles down the road, and to him that makes sense, because it hasn't had enough time to get to 15 miles down the road, because an hour hasn't passed for him.\n\n If you are watching the clock on bob's dashboard, it is running slow. When his clock shows an hour has passed, from your perspective it has taken 1.5 hours. So you'd expect to see the photon be 15 miles down the road, and again that matches up with Bob, since he has experienced 1 hour and it is 10 miles ahead of him, 5 miles down the road. \n",
"The best way I've heard it explained is to imagine a flat, 2d spacetime with 1 space & 1 time dimension each.\n\nIt's a flat field where \"time\" is north, and \"space\" is east. Your speed in each direction adds up to c, which is the speed limit. N+E=c\n\nSo when you are not moving through space, your speed is N+0=c.\n\nAs your speed through space increases, your speed through time must decrease. Just as when you turn towards the east while driving north through a field. Your speed in the north direction is reduced from the pov of an outside observer, even if you feel like you're always going the same speed.\n\nWe just have three more spacelike dimensions. To a photon, since its speed in the space dimension is always c, it's internal time dimension is 0. ",
"The newest Vsause video has a pretty good ELI5 description.\n\n _URL_0_",
"Watch this, Vsauce explains it really well ! - _URL_0_"
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3sv8u1 | the metal thing they press on fighters faces between rounds. | Between rounds, there's always a guy that presses a metal plate thing on the fighters face. What and why? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3sv8u1/eli5_the_metal_thing_they_press_on_fighters_faces/ | {
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"I believe it's cold like ice to decrease the swelling. Probably made of steel so it can be sterilized between fights.",
"It's an eye iron. It's a piece of steel that can be super-cooled to reduce swelling on a fighter's face, so they can continue to see throughout the match.",
"Hits to bony areas usually cause large swelling very quickly. There is no fat/muscle to blunt the force. \n\nThe piece you see is actually an \"eye iron.\" It is simply a cold piece of metal. That piece is applied and pressed into the swelling to minimize/reduce it. \n\nIt literally \"pushes\" the swelling down. \n\nThe cold helps, but the force is what really does the trick. \n\nYes, it hurts like hell. \n\nSide note: the method of pushing in swelling isn't just for fighters. A doctor once did it for my niece, in the ER, after she fell and hit her head on the corner of a table. We rushed her to the ER because it swelled up to the size of a softball in under 5 minutes. It was intense to watch. \n\n\n\n\n"
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6yjzd1 | what's the deal with all those scammy looking "we buy houses" signs i see at so many intersections? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6yjzd1/eli5_whats_the_deal_with_all_those_scammy_looking/ | {
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"They buy houses. Why do you think them scammy?",
"Opportunists. Lowball offers. If seller is motivated they get an easy and profitable flip.",
"They are looking for people in danger of foreclosure. It costs $5 for the sign. If they get one deal out of it, it was worth it. "
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3vbo9y | why do skilled nfl athletes still commit penalties? | I'm thinking in particular of something like grabbing a face mask. Is there some benefit to it that outweighs the penalty? Does it just happen too fast? I don't think that a player could grab one without knowing it, but I guess so? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3vbo9y/eli5_why_do_skilled_nfl_athletes_still_commit/ | {
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"Sometimes it is on accident and sometimes it is not. If I go to grab someone and they move at the last second, I may not grab them where I was trying to. Everything is happening so fast, and other times they just want to grab the face mask. ",
"Facemasks normally are inadvertent. Holding happens almost every play. I would have gone so much further if I learned how to hold and not get caught. \n\nNow though, there are so many new rules it makes the game flag football...\nSometimes the penalties are intentional if tempers are flaring.",
"For a penalty on the body like a facemask it can just be trying to grab their shoulder and missing. So in that instance it is just a case of things happening too fast. Remember, you may be one of the top linebackers in the sport but you're also playing against the best running backs and receivers in the sport. \n\nFor something like holding you can see players trying to get away with it sometimes and it can depend on what the ref is letting them get away with. \n\nFor timing penalties (i.e. false start) there are a lot of mind games that happen when both sides line up. Quarter backs will use fake counts to try to get defenders to move early and defenders will fidget to try and get the offensive line to move early. ",
"It's tough to speak to each individual occurrence. But for every penalty that does get noticed, there's many more that go unnoticed.\n\nFace masking isn't the best example of this, more often than not, if you're going to face mask someone, you're going to get caught.\n\nHolding, however, is a much easier point to prove. The risk of getting caught holding is quite low, and the reward is quite high. If every hold got called in football, there would probably be a penalty on every play. It doesn't however, so players are generally willing to risk it.",
"You've gotten some good answers but I'll add a twist to them. If you're an offensive lineman and you get blitzed. You can see the middle linebacker coming at you at full speed while you're engaged with a defensive lineman. You try and block him but he's also strong and skilled - and he has speed on his side.\n\nYour choices are:\n\n1) Put up a token resistance you know he'll blow through where he will likely sack the ever loving fuck out of your QB.\n\n2) Throw your arm out and grab what you can.\n\nIn the first scenario you are risking a turnover and injury to your QB. As we've seen with Dallas this year, injuries to QB's are a bad thing.\n\nIn the second scenario there is a small chance the hold won't get seen. The refs are good but there is a lot going on so sometimes shit goes unnoticed. Assuming you are flagged though you have at least protected the QB and the ball. Coaches in general will take a 10 yard penalty over risking injury to the most important player.",
"* stopping someone with a penalty is often better than not stopping them at all\n* not all penalties are caught, and athletes often try to get away with as much as they can\n* intimidating an opponent might make them second guess the next play\n* keeping your balance, avoiding blockers, and tackling someone trying to escape, there is a lot going on there, and sometimes you are not aware of everything you are doing until it is too late"
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3a810t | how bulletproof are dinosaurs? | I just saw Jurassic World, and in the movie, (very mild spoiler alert) the Indominus Rex seems pretty impervious to normal rifles, a helicopter-mounted minigun, and she even shrugs off a pretty much direct hit from a rocket launcher thing. I know that, within the movie's logic, she was made to be the strongest, largest, toughest, etc. dinosaur, but I was just wondering how various real dinosaurs would fare against firearms. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3a810t/eli5_how_bulletproof_are_dinosaurs/ | {
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"Dinosaurs don't have magic anti-bullet properties, and bullets aren't magical things that do abstract \"damage\" like in movies and video games. Bullets punch holes in things. That's it. Large animals have more blood to lose, more muscle to draw on in emergencies, and more flesh to pierce before irreversible damage is caused. Thus, to take down a large animal, you need to punch a *lot* of holes, or one very big hole. There are special guns and ammunition necessary to take down elephants. [Here is one side-by-side with an AR-15/M4/M16 combat rifle cartrige](_URL_0_). Thrice the width, and probably 30 or 40 times the charge. ",
"Well, how does a bullet kill a person? It either damages an organ so badly that it can't work anymore, or it hits a big enough blood vessel that the person bleeds out.\n\nSo when you look at the I-Rex, it's basically a huge, scaly mass of muscle. Most bullets probably can't get through all of that dense muscle to actually hit a major organ. Its blood vessels are probably large and there are probably lots of them; a bullet hitting some of the smaller, outer ones isn't going to get him to bleed to death. And it's not like a bullet can hit his aorta or anything, because that's in the center of a heavily muscled, bony, scaled body.\n\nSo it's sort of like shooting toothpicks at a human. Sure, they'll hurt, and if you get hit with enough of them in the leg, it might be tougher to move your leg. But they aren't going through and causing major damage that could really hurt the I-Rex.",
"Scroll over for TLDR. To see how this answer comes about, I would advise skipping over the spoiler: [Spoiler](/s \"We can't say for sure, but if we scale up based on an elephant, the minigun on the A-10 Warthog is enough to take it down with one bullet. It would likely stand up to a few rounds of something like a helicopter based minigun though.\")\n\nThis is actually a fairly complex question when you get down to it. While we can't be sure exactly all of the properties of dinosaurs, we can make some comparisons to modern animals. For example, many animals have very tough skin to deter predators, skin which can repel small arms fire. \n\nWhile bullet placement is the most important factor in bringing something down, the energy conveyed by a bullet is a good way to see if your gun is adequate to certain game. Squirrels and the like are fine with around 300 ft-lb of energy. Meanwhile, deer need around 1000 ft-lb of energy. Once you start getting to thicker skinned, more dangerous prey, you want at least 4000 ft-lb for something like a buffalo, and 5,000+ for an elephant. \n\nSo, if we apply this to the dinosaur in the movie (judging by the information of the J-park wiki), it looks to be about 50% larger than a t-rex. A principle known as the [square cubed law](_URL_1_). Means that this would put it about about 3.4 times the mass of the t-rex (7.5 short tons (I can't be bothered to convert units)). Scaling up the bullet energy puts a comfortable range of over 140,000 ft-lb of energy! Coincidentally, this is almost exactly the energy of a bullet from the A-10 Warthog, which has the power to punch through an inch+ of steel. And does [this](_URL_0_).\n\n"
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4u32z6 | rules about reasonable suspicion vs. probable cause/just cause | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4u32z6/eli5_rules_about_reasonable_suspicion_vs_probable/ | {
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"Cop here:\n\nReasonable Suspicion:\n\nAn officer reasonably belives a crime *may have* occurred.\n\nFor example: An officer is patrolling an area where car break-ins have been a problem. He sees a man in a hoodie (even though it's warm outside) looking into a car window.\n\nHe has reasonable suspicion a crime may be occurring. He can legally stop that man and hold him long enough to determine if a crime occurred or not.\n\nProbable Cause:\n\nA higher standard; an officer has reason to belive a crime probably occurred.\n\nSame example as before, but the officer finds several cars with broken windows, the man has broken glass on his jacket, and a wallet from one of the cars.\n\nReasonable Suspicion is the standard required for a stop or detainment. \n\nProbable cause is the standard for am arrest.\n\nThere is no \"just cause\" in the US legal system. \"Beyond a Reasonable Doubt\" is the standard needed to *convict* a person of a crime.\n\nAs for vehicle searches:\n\nAn officer needs probable cause to search a vehicle without your consent. The exception to this is what's called a \"Terry Frisk\" in which an officer may *frisk* (or pat down- not search) a person or the lungeable (easily-reachable) areas of a car for a weapon if the officer has reason to belive a person may be armed.\n\nThe smell of marijuana is probable cause. It seems to be a common belief that cops will fake smelling marijuana in order search a car. I've personally never seen this happen and I would doubt that it happens often at all.\n\nYou have the right to refuse a search if the search is consensual only.\n\n*Edit: fixed autocorrect error.",
"I'd like to hear about the rules and regulations governing searching someone's cell phone history if you know anything about that too. "
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2eh8cc | what role does a director actually play in creating a movie and what are the signs of a poorly directed movie? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2eh8cc/eli5what_role_does_a_director_actually_play_in/ | {
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"The director is the head honcho of the movie set. What ever you see on the screen is because of what the direct wants you to see.\n\nThe director has the power the take the saddest script and redirect it to be the happiest thing you've seen.\n\n\nThe director is the conductor on the emotional train we call cinema.\n\nWithout the direct there is no vision and with no vision there is no movie. \n\n",
"The Director of a film (or a play, or a television show episode) is the person responsible for the creative vision of the piece. They create a concept from the script (which may or may not be something concretely found in the script, it may be metaphorical or tangential) and from the concept lead the design and production team towards a collaborative vision. Once rehearsals/filming have begin, the director blocks the piece (i.e. tells actors where to move), provides objective and subtextual support to the actors (i.e. tells them why they are saying the things the writer wrote) and ensures that the visual style and setting are within the original vision or concept parameters.\n\nIn film, they also work closely with the DP, first story-boarding the script, and then, once on set, making sure that each shoot is framed, blocked and shot per their vision. Including ALL design aspects, from the color of the walls to the type of purse a character might wear.\n\nIn essence they are the Captain of the ship. A lot of my notes below can also be laid at the feet of bad writing, but in film (less so TV and theatre) directors have a great deal of oversight on the writing, so they are typically held accountable if the writing is terrible.\n\nA film which has been directed badly will usually (but not always, the problem with a collaborative art form, which is what film is, is that there are many, many chefs in the kitchen. However, since the director tends to get the credit when everything works, they also tend to get the blame when it doesn't)--usually show the following flaws:\n\n1. Incoherent story telling. You don't know what is happening. Or why it is happening. Or who it is happening to. Sometimes things are just blatantly implausible.\n\n2. Cliche or trope ridden dialogue/shots/events. You feel like you've seen all of these things before. All the characters are stereotypes, all the plot points unfailingly predictable. Note: cliches, tropes and stereotypes can all be used well. But bad directors tend not to.\n\n3. Bad dialogue. Dialogue that is forced and unnatural. Dialogue that is too on-the-nose. People telling other people things instead of doing things. People explaining how they feel ad nauseam. Dialogue spoken only to allow for the plot to push forward, leading us to:\n\n4. Coincidental plotting, or plots hole you could drive a freight train through (not the small inconsistencies that almost every movie has, but HUGE giant massive oh-my-god-this-movie-is-broken plot holes). Coincidental plotting is when everything that has to happen for the plot to move forward does, without any effort on the part of the hero (or the bad guy).\n\n5. Bad acting. Directors are responsible for getting a performance out of their actors, so even if the actor can't act (one reason why casting is important) the director is still the one people are going to hold responsible for any painful moments on screen (this is less true in TV and theatre). \n\n6. Over or under designed. Over designed is when the concept/vision of the piece becomes more important then any other element. Think 300: Rise of an Empire or Sin City: A Dame to Kill For (not-at-all-oddly, both Frank Miller graphic novel adaptations, where the look was where the design team started with). Tim Burton is also a well-known director who can go to far with his vision/design to the point of over balancing the movie. Under designing is when there is a lack of design and the production feels (usually) cheap or not-thought-through. Good design elevates the narrative, supports the characters and provides visual clues to the audience about what is happening--excellent design can comment on and complement the action, enhancing the entire experience.\n\n7. Movies/TV only: bad editing. Either because there were technical difficulties during filming and the needed shots weren't gotten (or a director wasn't prepared and didn't get the shots they needed), and therefore the editor is attempting to make up for missing and/or bad shots; or because the editing itself is just bad. Odd cuts, odd shots going back to back, odd audio issues. Various other things. While most early directors at a studio on a movie won't have any say over the final cut, most editing issues are from a lack of footage (which is the director's issue), not bad editing. OR a director who does have final cut approval and shouldn't, which is where you got a three-hour movie that should have been 2 hours and 10 minutes max.\n\n8. Poor production value. An overall feel that the movie wasn't cared for (this isn't about money, this is about time and support). Usually shows in bad lighting, bad audio, bad set dressing, bad costumes--just an overall sense that these things weren't considered important or there wasn't time to pay attention to them.\n\nA film, tv show or theatrical play is an immense, multi-part beast, and the Director is the one that tries to tame it. To varying degrees of success. Every director probably has one (or many) bad movies to their name, as its how we all learn. The more telling test is not if they directed a bad movie, but if people wanted to work with them again. And, sometimes, the love of the thing they are creating can shine through the worst movie and make it, somehow, good (think Sam Raimi's original Evil Dead).\n\nHope that helped!",
"The actors portray characters in the story. The costumers and set decorators are illustrators to the story. The director is the storyteller.\n\nA character has a motivation or goal, the director advises the actor how to show the goal as part of the story.\n\nEvery good story relies on drama. Drama comes from conflict. Conflict in a traditional sense is \"the hero wants to do something and the villain wants to stop him\". Better conflict makes better drama, the best way is to make the villain stronger than the hero. So, the hero is trying to win something, but the villain is stronger than the hero and is trying to stop the hero. \n\nA really good storyteller is good with \"power inversion\", turning the power structure upside-down. How does the hero change himself, so he can overcome the more powerful villain?\n\n",
"The director also sets the tone on set -- the entire cast and crew follow his/her lead. The really great directors I've worked with [14 years in film/tv] came in prepared (knowing what they need to get) confident (by trusting the individual department heads but unafraid to kick a little ass if specific departments need the prodding) and decisive (each department hangs on the director's answers so the best directors have answers quickly and definitively).\n\nThe director should have the entire finished product in his/her head so the rest of the crew doesn't have to wait on his/her process.\n\n",
"/u/daijobu16 provided a very good answer, but I think I can simplify it a bit.\n\nOf the people involved in the creation of a movie, you have two job titles that can be said to be \"in charge\". First, the producers. A \"producer\" is often the money-man, and the person running the whole thing, including hiring the director, marketing the movie, getting it into theaters, etc.\n\nHowever, the role of a \"producer\" can be a little vague. People can get \"producer\" credits for all kinds of things related to the creation of the movie. For example, if it's a small movie, and you allow them to shoot some scenes in your house, they may give you a \"co-producer\" credit as a form of payment.\n\nSo speaking vaguely, the producer is the business-man in charge, but the director is the creative person in charge. He actually makes the movie. He oversees script re-writing, casts the movie, oversees shooting, oversees editing.\n\nWhat he does exactly can vary from movie to movie, and different directors have different preferences. Some directors exercise more control over every individual shot, while others give their cinematographer and camera man more leeway. Some directors tell the actors exactly what they want the actor to do, while others make it more of a collaborative process. Some directors edit their own movies, while others will work with editors and allow those editors some freedom. However, it's the director's job to oversee the whole process.\n\nSo the role isn't set in stone, and each director finds what fits for them, but most of the time, directors will cast all the major roles, tell actors what kind of performance they want, choose a lot of the shots and decide how things should be lit, and provide a lot of guidance to the editors.\n\nSo if anything in the movie sucks, it's the director's fault to some degree. The script might be lacking. The actors might have sucked. The editor might have butchered the edit. The camera man might have shot something with poor focus. But the director was supposed to be overseeing it all, so the director is still at fault, at least to some degree. The only thing that's kind of outside of his control is meddling from the producer (or studio or whatever)."
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3y4ilm | why do so many great mma fighters have multiple losses on their record compared to boxers? | It seems to me that the truly great MMA fighters tend to have multiple/more losses on their records when compared to boxers, where the truly great ones tend to have none or one or two defeats only. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3y4ilm/eli5why_do_so_many_great_mma_fighters_have/ | {
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"There's more ways to lose in mma. Boxing is more technical and skill makes a bigger difference than blind luck. Also, politics. Most boxers with only a few losses compared to wins have some very questionable decisions in their favor",
"Part of it is the infrastructure of the sport. UFC is now head and shoulders above any other MMA promoter, so they got most of the best fighters and make them fight each other. In boxing, there are 4 organizations giving out belts, and each fighter has his own promoter. Boxing matchups become business decisions instead of \"what's best for the sport\" decisions, because so many people want a piece of the pie. The UFC has control over it's own pie because the fighters need to come to them to compete against the best",
"A couple of reasons:\n\n1) MMA is more physically tolling on the body. Even in training, you get hit, get slammed and get submissions put on you. More parts of the body are involved so there are more places to get injured. You are pretty much safe below the belt in boxing and don't have to worry about falling unless you get knocked out. You have to worry about both of these things in MMA.\n\n2) It depends on who you consider \"a great\" and when you consider them one. Anderson Silva didn't lose between 2007-2012. Fedor didn't truly lose from 2000-2009. GSP only lost twice from 2002-2013. Fedor's now lost multiple times, but it doesn't make his original run any less.\n\n3) With UFC being the only real show in town right now and MMA matchups being booked by a company, and not individual promoters, it's hard to duck and dodge the best competition like boxers do. Boxers don't really have to face anyone they don't want as it's more on individual drawing power, while UFC is a full company. UFC will be around if say Rhonda Rousey leaves. Random boxing promoter may not be if his man leaves.\n\n4) UFC and MMA have a lot less weight classes than boxing. There are 17 boxing weight classes right now. UFC has 8. That means the better talent is less spread out and you have a lesser chance of getting by on favorable matchups than skill.",
"Adding to other answers, MMA is also a relatively new sport and is constantly evolving. It is difficult to stay at the top for a long time when new fighters come along with different skills, and training built on the experience of others.",
"Short and indirect answer: There are far more boxers, historically but also today, than MMA fighters. \n\nDetailed answer: More competitors means more chances to pile up easy wins. Almost every famous boxer has not just a good record, but a lopsided record. *Ring* magazine's [top 10 pound-for-pound boxers](_URL_1_) are a combined 333-9-7. \n\nThat's because they all spent their early years fighting grossly outclassed boxers who probably ended up quitting shortly thereafter. \n\nTake the top boxer in the world, 44-0 [Roman Gonzalez.](_URL_0_) Here are the career records of the first few guys he faced, in chronological order: \n\n* 0-6-1\n* 1-7\n* 0-3\n* 14-12-2\n* 3-13\n* 9-17\n* 5-23-3\n* 5-23-3 (same guy)\n\nYou get the idea. If there were fewer boxers - i.e., if the bottom level of boxers didn't exist - the great ones' records wouldn't be so lopsided.",
"Can't duck talented fighters when you're the champ. Also there's many ways to win a fight and no one fighter is the best at wrestling, judo, jiu jutsu, kickboxing, boxing, sambo etc etc. Anyone can get caught by a superman punch or armbar, no one stays on top forever. It's understood that you don't have to be undefeated to be an excellent fighter. \n\nAlso no high level MMA organization gets away with putting tomato cans against top fighters. Top ranked fighters generally fight top ranked fighters, it's rare to see top 10 fighters against loosing record nobodies. A popular up & coming fighter may rack up several easy wins on the amatuer or C list shows but A list organizations have little reason to prop up a fighter. The best fights are battles, not one fighter outclassing another all fight. "
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1q3khx | why, as an adult, i take the same amount of cough syrup or other medicines as a 12 year old when i am heavier and more physically mature? | I was just wondering this, does it have to do with decreasing returns? I just found it funny that a 12 year old who weighs around 45 kilos takes the same amount of cough syrup or panadol as an adult male who usually weighs upwards of 65 kilos, and physically has completed growing and developing (this may or may not have anything to do with it). | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1q3khx/eli5_why_as_an_adult_i_take_the_same_amount_of/ | {
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"The dosage is just what they know is safe but still effective generally. If you feel like the recommended dosage is insufficient you can go above. Of course if something goes wrong you can't sue the company because you went against recommendations, and you didn't hear it from me that it should be safe, but for the very reason of lawsuits the recommended dosage is already a bit conservative. ",
"Coating-action aside, some medication dosage is tied to metabolic activity rather than body weight. When a kid's body is mature enough to fully metabolize medication, they're ready for the adult dose. In between age 12 or so and geriatric age, and barring some factor like liver disease, one's ability to metabolize meds doesn't change much even though your weight might. Caveat & disclaimer: I'm not a health professional-- this is just paraphrasing what my kid's pediatrician told us. ",
"As an adult you could always, you know, just take more than instructed. "
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4g0vkh | if gravity is actually the earth accelerating upwards and the earth is spherical, how can it accelerate upwards in all its surface? | As explained here _URL_0_ | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4g0vkh/eli5_if_gravity_is_actually_the_earth/ | {
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"Did you get the bit where it mentioned frames of reference? Because that's what this is all about.\n\nNow, ignore the planet. Ignore all the big stuff around here. Ignore me, ignore you. We're going to talk about two tennis balls in deep space. They're just there, in space - they're not sitting on a table, they're not sitting on the ground. They're just there.\n\nNow, they're getting closer to each other. So, is it correct to say that:\n\n1. Ball A is moving towards B? \n1. Ball B is moving towards A? \n1. Both balls are moving towards each other?\n\nWell, it could be any of them. It depends on what you define as your frame of reference.\n\nIf you **decide** that B is stationary, then case 1 applies. If you decide that A is stationary, case 2 applies. If you decide that an invisible point in the middle of the two is stationary, 3 applies.\n\nThe thing is, we tend to think of the Earth as the be-all and end-all. It's big, it's kinda constant for most of us - it just sits there under our feet, not seeming to move.\n\nBut... what about the tennis ball example? We can decide which thing moves. If I hold a tennis ball above the Earth and let go, the same thing applies. I can **decide** whether the ball moves, the Earth moves, or both."
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dwmt46 | what the hell did people think sports concussions were before? | Over the last 15-20 years we’ve seen professional sports crack down on concussion safety, mainly the NFL, but it’s also been a issue with pro-wrestling, and boxing.
I understand that CTE has been discovered and can only be officially diagnosed after an autopsy.
HOWEVER, what the hell did people think concussions were before? I cannot understand how any brain injury could be seen as anything less than critical.
We’ve had the term “brain damage” forever. I just don’t see how people are just now understanding that a brain injury is always serious. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dwmt46/eli5_what_the_hell_did_people_think_sports/ | {
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"Well the expression for a concussion was usually something like \"he got his bell rung\" to explain the immediate symptoms of concussion. CTE is different that a concussion though. It is caused by many concussions over time, slowly building, as we understand it now, but is often seen later in life.\n\nSo a normal guy racks up a few concussions and recovers. Then 20 years later he has real mental health problems. There was no way for them to link it to the bell ringings he got in high school football. \n\nBasically they didnt realize these impacts and symptoms which would subside fairly quickly were having permenant impact on the brain.",
"It was hard to see the long term effects at first. You get \"your bell rung\" or concussion and you're fine a few days later and everything seems to have healed and you get back to it. It's only decades later that people start getting more aggressive and impulsive as a result of CTE. Might've been hard to connect the dots at first. I'm sure the NFL did their part to not release any information they had about the dangers of repeated concussions as well"
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afayf9 | the brain is very important, and very complex and exists in a confined space; given that why is it that tumors in the brain are able to get so large before being noticed? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/afayf9/eli5_the_brain_is_very_important_and_very_complex/ | {
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"The common symptoms of brain tumors are just that, common. Headaches, nausea, dizziness, and so on can be caused by a lot of other things and the symptoms themselves can come and go. It's usually once more serious symptoms appear or a pattern of symptoms is recognized that a patient undergo MRI."
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11oyyv | openoffice vs. libreoffice (vs. microsoft office) | OpenOffice vs. LibreOffice: What's the Difference, why did they split, etc..
.
(OpenOffice or LibreOffice) vs. Microsoft Office: Is one better then the other; What are the limitations of each, or is it just personal preference.
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/11oyyv/eli5_openoffice_vs_libreoffice_vs_microsoft_office/ | {
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"I haven't used OpenOffice since the split, nor MS Office since before then, so I can't comment on the differences between them today. But I can give a little background on the split itself. \n \nOpenOffice used to be run by Sun. [In 2009 Oracle bought Sun](_URL_0_) and maintenance of OpenOffice became less of a priority - basically Oracle put it on the back burner. LibreOffice was created by the community in response to that, and a number of old OpenOffice contributors now work on LibreOffice instead, and many of the financial backers of the project also followed. \n \nOracle later donated OpenOffice to Apache, so now both software suites exist, and the short version is that LibreOffice is the spiritual successor to OpenOffice, and the new OpenOffice is essentially a completely new entity.",
"OO vs LO:\n\nOO was made by Sun with a huge community to develop it. When Oracle bought Sun in 2009, a large segment of the sevelopers weren't fana of Oracles plans for OO. So they \"forked\" the project (copied the code, changed the name, and ran it as a seperate project; this is very common in the realm of open-source software) into LO. Oracle eventually donated OO to Apache, so at this point its really just personal preference.\n\nOO/LO vs. MSO\n\nWell, the main difference is MSO is closed-source, commercial software, while OO/LO are open-source. They both do the same thing but in different ways. OO/LO is also free while MSO costs money to buy."
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"http://www.openlogic.com/wazi/bid/188115/LibreOffice-vs-OpenOffice-org-Showdown-for-Best-Open-Source-Office-Suite"
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|
enpxss | - when you dent your car and the auto body shop uses filler to fill the dent, what are they using? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/enpxss/eli5_when_you_dent_your_car_and_the_auto_body/ | {
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"Polyester resin/putty, sometimes mixed with fiberglass for extra strength. Bondo is a fairly common brand, and other brands are often referred to as \"bondo\" as a result."
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716qta | is it pitch black in space or is there enough ambient light to see something held in front of you? | Assuming you're not in the vicinity of a star, of course. Somewhere like Voyager's position, 10 billion miles from earth, could you see your hands? Total darkness? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/716qta/eli5_is_it_pitch_black_in_space_or_is_there/ | {
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"Somewhere on the Internet NASA has a page describing how much light there is and what you can see. If I were there I would be sure I had a flashlight. Maybe I would sprinkle powder and shine the light on the powder to get a diffuse illumination. Or I could shine the light on a nearby surface to use the surface as an illumination source.\n\nIt really is pretty dark. I mean, think of a moonless night on Earth. It would be no brighter.",
"Light would be very dim.You would probably be able to make out objects at close range, but not read or see fine details.\n\n[Here's a good r/askscience post on the subject](_URL_0_)",
"In space, there's nothing. The only source of ambient light comes from stars. That means if you are inside the solar system and there isn't a planet in the way, you're gonna see very well. Things will be very bright on the side facing the sun, but shadowed on the other side.\n\nIf the sun is blocked, you will still receive light from other celestial bodies and the milky way, which will give you extremely dim vision. You will be able to see a little bit in front of you, but not enough to distinguish complex things.\n\nIf you leave the solar system, same thing, but even darker because celestial bodies like the moon or saturn will reflect a little bit of light, depending on where you are. So without those, it'll be pretty dark. Very difficult to recognize objects probably, but if someone waves something in your face you could see it (Especially since it'll block stars behind it from your vision). If you leave the milky way and hang out in between galaxies, it'll be even dimmer, so much that it's gonna be almost impossible to see anything.",
"Ask yourself, how dark is it on a new moon on earth in a place without artificial light? Like on a field in the middle of nowhere."
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9s31si | how do cinema projectors have such high quality compared to personal home projectors? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9s31si/eli5_how_do_cinema_projectors_have_such_high/ | {
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"They got a light source (think: a bulb) that is consuming so much energy it's crazy compared to the tiny box you got in your own living room.\n\nAnd bulbs always create excess heat that needs to be cooled away with active cooling. i.e, fans. Fans are noisy.\n\nBut no-one in the cinema cares, because that projector is in it's own room, with a glass window. No-one in the audience hears the fan.",
"A big difference is that they use three display devices (DMD or LCOS) to make red/green/blue, so they don't need a rotating filter wheel. Better screens and lenses help too. It's like the difference between a cheap digital camera and a good DSLR and lens. ",
"It's the same like in every industry doing essentially the same like consumers do themselves.\n\nYou can buy a nice little light effect and it would be enough for you but a company which is earning their money by using lights has the money and the knowledge to buy a more professional product.\n\nThe projector you are using at home may cost around a thousand dollars, the projectors used by professionals cost much more that that. For that much money they get a better lamp, better optics and the ability to play movies that are stored in a way that is too expensive for the end consumer. Also they will use a much better screen, which makes a lot of difference.\n\nThey spend hours in calibrating the projector what wouldn't be worth for anyone showing some content for less that a couple thousand people.",
"Home projector pricing makes no sense. Projectors come down to 4 things:\n\nBrightness, typically measured in ANSI lumens. More is better, because it means the picture light is stronger than the ambiant light. Typical home projectors will be between 1500 - 3500 ANSI lumens. The outside advertising projector at my local cinema was 8000 ANSI... \n\nContrast, same as a TV. Best noticed displaying a black image. More is better.\n\nKeystone, vertical and horizontal are key for placing a projector. It let's you bend the image so you can offset the projector. As projectors can be 4m away a small offset causes a big picture tilt, keystone let's you fix that. \n\nDisplay technology. Optima like a lot of projector brands fire a white beam and encode a colour signal onto it. As the ambiant light increases this causes the much weaker colour signal to fade. Sony, Epson, etc.. have a multi beam technology. While named various things, it boils down to firing red, green and blue beams at the wall. Since there are coloured beams the image doesn't white out.\n\nNow why are home projectors poor? Because adoption is less so places sell projectors as a home theatre experience (thousands of pounds). Projectors aren't sold on their specifications but audiophile gimmicks. I have friends who spent £2k on an optima from richer sounds that was half the lumens, lower contrast and the same resolution as my £400 Epson projector.\n\nMy favourite gimmick 5 years ago was dlp (traditional bulb) vs led. Led had such a price premium that 5 years of daily use later I'm still financially better off by going dlp. \n\nBecause there isn't a clear specification war going on the market stagnated. It took Epson 5 years to make a projector better than my current one (eh tw 490 vs eh tw 650).\n\nAlthough something happened this year, market seems much saner, as I was going to post examples and failed to quickly find one.\n\nEdit - typos/clarity",
"Like everyone else has said, money. It's literally like the difference between a used Honda and a brand new Rolls Royce. A movie theater projector costs around $75k-$100k and 20,000-30,000 lumen,. Everything about it is precision made, calibrated, and maintained. You can get home theater projectors with DLP 3chip technology, 4k video, 5000 - 8000 lumens, and interchangeable lensing, but it still won't come close to the one at the theater.",
"Some have multiple lamps...some have extremely powerful lamps. Some have multiple extremely powerful lamps...that are maintained by professionals. Lenses are excellent, and the projectors have great ventilation keeping them dust free and cool. They also have specialized software optimally running them. They are also mounted at optimum distances/angles...and the screens are designed to be used with them, so they are very bright/clear. Also the files they play are high resolution, using specialized players/processors...that are connected to the projectors with digital cable (fiber/dual link dvi).",
"Cinema projectors have lamps that can output 20,000+ brightness measuring units (lumens). Home projectors do like 2,000."
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2alzkt | why do chiggers and/or mosquitos seem to bite around a person's joints (e.g. ankle) | Why God? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2alzkt/eli5_why_do_chiggers_andor_mosquitos_seem_to_bite/ | {
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"In short, evolution or The Fall, depending on your religious flavor or lack thereof.\n\nThe most prominent reason is the fact that the blood vessels are very close to the surface of the skin over these areas. Mosquitos have the capacity to sense heat as well as (some speculate) the capacity to sense the blood pumping through blood vessels."
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kptcj | how is facebook exploiting me? | I keep reading it in memes and all over reddit. How? Thanks! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/kptcj/how_is_facebook_exploiting_me/ | {
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"Basically anything you submit to Facebook becomes their property; Pictures, personal information, everything.\n\nPeople complain about privacy and then go and spill every single detail of their life to Facebook, thus Facebook is \"exploiting\" idiots.",
"The whole premise of facebook is in the interests of exploiting the public.\n\nPeople who haven't stopped to think about it think that facebook is a service provided to the general public allowing us to connect electronically with the people in our lives. They think that this service is financed by the tiny ads on the margins.\n\nIn fact, facebook is a service for companies and corporations. Facebook is the most accurate, sophisticated demographic generator in the world. When a company wants to advertise to 23 year old, catholic, single, Arab linguists, from America, who like anime, they can go to facebook and buy ads that specifically target those people. Making it exponentially more likely that the people seeing those ads will click on them. Thus facebook only needs to be good enough to the users (us) that we don't abandon it wholesale, while at the same time prompting us to upload as much information about ourselves as possible.\n\nI saw a political cartoon on here earlier. It shows two pigs in a slaugherhouse called \"facebook pork\" (or some other such label that indicated beyond doubt that it was a slaugerhouse). And the pigs are inside marvelling, \"and there's free food too?! A safe place to sleep?! This is awesome!!\" Of course, they don't know that their whole purpose of being in there is so that they can be fed to people.\n\nThe only real question is whether Zuckerberg said \"I think this would be a great way for people to connect with each other\" and then realized the best way to monetize it. **Or** if he said \"you know what would sell like hotcakes? Really specific demographic information. I think I know how to get it.\" (a la chicken/egg)",
"Basically anything you submit to Facebook becomes their property; Pictures, personal information, everything.\n\nPeople complain about privacy and then go and spill every single detail of their life to Facebook, thus Facebook is \"exploiting\" idiots.",
"The whole premise of facebook is in the interests of exploiting the public.\n\nPeople who haven't stopped to think about it think that facebook is a service provided to the general public allowing us to connect electronically with the people in our lives. They think that this service is financed by the tiny ads on the margins.\n\nIn fact, facebook is a service for companies and corporations. Facebook is the most accurate, sophisticated demographic generator in the world. When a company wants to advertise to 23 year old, catholic, single, Arab linguists, from America, who like anime, they can go to facebook and buy ads that specifically target those people. Making it exponentially more likely that the people seeing those ads will click on them. Thus facebook only needs to be good enough to the users (us) that we don't abandon it wholesale, while at the same time prompting us to upload as much information about ourselves as possible.\n\nI saw a political cartoon on here earlier. It shows two pigs in a slaugherhouse called \"facebook pork\" (or some other such label that indicated beyond doubt that it was a slaugerhouse). And the pigs are inside marvelling, \"and there's free food too?! A safe place to sleep?! This is awesome!!\" Of course, they don't know that their whole purpose of being in there is so that they can be fed to people.\n\nThe only real question is whether Zuckerberg said \"I think this would be a great way for people to connect with each other\" and then realized the best way to monetize it. **Or** if he said \"you know what would sell like hotcakes? Really specific demographic information. I think I know how to get it.\" (a la chicken/egg)"
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52ocer | where does the sound from the car's blinker actually come from? | Seems like it is magically emanating from the dashboard. It seems like a mechanical mechanism, but maybe new cars have blinkers that produce sound electrically? Always made me wonder. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/52ocer/eli5_where_does_the_sound_from_the_cars_blinker/ | {
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"It's a relay with a reed switch. Makes noise when activated. They're usually under the dash on the driver's side.\n",
"It comes from a relay switch that is turning off and on. The relay is a small electro-mechanical switch that uses a small voltage, to switch on or off a higher voltage. In the case of a car blinker it is a type of switch that turns off and on when the contact is closed. This can be a purely mechanical timing, or in response to a circuit timer. In mechanical designs, the switch closes, and heats up as current flows, causing it to pull away and break contact, and the light goes off, then as the switch cools it bends back and makes contact again, and will keep going back and forth like this until the control circuit is broken. \n\nThis is also why blinkers may go faster or slower depending on the temperature outside, and why sometimes when you replace the blinker, the car flashes much faster or slower than it used to. \n\nMost of the high voltage or high current devices in your car are switched off and on using relay switches that don't cycle. IE they stay on until you turn them off. The relay allows you to safely use a small voltage, to control a much stronger voltage/current without risk of fire or electrocution.\n\nIn its simplest form, imagine you had a little magnet on a light switch on your wall and you put an electro magnet next to the switch. You can trigger the electro magnet using a 9v battery and this will flip the switch turning your lights off. Reverse the polarity and now it's thrown the other way and the lights come on. Since your 9v battery isn't in direct contact with the high voltage wiring inside your wall, you can safely handle it without fear of electrocution. \n\n",
"There are some cars which use speakers to either make or augment the sound. A coworkers f150 does it. "
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1osc17 | paralysis, specifically if you are paralyzed below the waist, is your genitalia also paralyzed? can a man never have an erection for the rest of his life? | I know if you are paralyzed below the waist you practically lose all function of your legs and have to use a wheel chair for the rest of your life...
But does this extend to our personal parts? Would a man never be able to have sex or even masturbate?
Just something that has been on my mind..
FYI: I'm kinda a noob and this is my first post but I LOVE all of you other redditors :D Also i searched ELI5 for another post pertaining to this subject, I'm so sorry if such a post already exists! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1osc17/eli5_paralysis_specifically_if_you_are_paralyzed/ | {
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"Most people who are paralyzed from the waist down do not lose the ability to have and enjoy sex.",
"It depends.\n\nSome people are (effectively) paralyzed because of a muscle issue. So, the nerve connection between brain and muscle is still there, but the muscles can't contract when the signal reaches them, or they're too weak to truly move. So, if it's just an issue of \"the muscles in the leg no longer function properly,\" the genitalia will still mostly function. This would be the case for someone who's effectively paralyzed because of muscular dystrophy, for example.\n\nSomeone with muscle issues may have problems with ferility, though, especially childbirth. A mother whose muscles are too weak to force a child out would have to have surgery to give birth, for example. Men also may have issues ejaculating, because the muscles that actually force the semen out can be too weak. Incontinence can also be an issue.\n\nWith nerve issues, it's more complicated. There are injuries or diseases which affect the brain's ability to actually send signals to the muscles. If the nerves that go down your leg through the hip are cut off or damaged, the genitalia aren't affected. If there's a spinal problem where the cutoff is towards the base of the spine or whatever, that can affect genital functioning. No nerve impulse, no genital functioning. Not only can you not feel anything when the nerves are cut off, but the \"automatic\" reflexes that occur without you doing anything conscious (like your leg kicking when the doctor taps your knee) also fail, since they're also routed through the central nervous system.",
"Since others have hit on non-spinal cord injuries, I'll just focus on those. Your body has a main pathway that moves information from the ends of your body to the brain. This is called the spinal cord. Some of that information never makes it fully to the brain. Instead, there is a path of nerves that moves from one part of the body, then to the spinal cord, then return back to the origin. This is called a reflex arc. So, you have two ways information moves: From finger to brain, and from finger to spinal cord to finger. Let's use a simple example. You are using a hot stove and touch one of the burners. Two things happen: First, and quickest there is a signal sent through the reflex arc causing (Finger, nerve to spinal cord, back to finger) your finger to pulls back very quickly. At the same time, but taking a millisecond or two longer is the sensation of HOT!!! being sent to your brain for interpretation. The purpose of the reflex is to be quicker than the interpretation so you are out of danger without necessarily knowing why immediately.\n\nIn the case of spinal cord injuries, a lot of this depends on where the injury is. If it's too low on the spinal cord, then the nerves needed for both erection (some terminating in the spinal cord as a reflex arc, others continuing to the brain for full interpretation) and the reflex arc nerves for ejaculation will be cut off. If the break is higher, then you might get someone who can have an erection, and have an ejaculation (a function of the reflex arc), but they may not feel it. So, they get hard, ejaculate, but get no sensation out of it. "
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6623yk | theresa may's announcement of the snap election | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6623yk/eli5_theresa_mays_announcement_of_the_snap/ | {
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"May's Blue party think they're currently doing a lot better than Jeremy's Red party. Because the Blue party are in charge of the tree house just now, they've decided to hold the next election earlier than they need to, which is called a 'snap' election.\n\nAll the members of the tree house get to vote in whether or not the snap election will take place, but if Jeremy and his friends say no then everyone will think they're scared to stand up to May. Everyone who's not a Red or a Blue thinks that they can maybe steal a few of the better chairs in the tree house from the Reds during the confusion. "
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js20b | how military units get their numbers? like where does 25th id come from? wheres 24th id? | I dont understand the number structures at all and what they symbolize. I get that there is like a 1st INF DIV but why is their FA unit Charlie 3-07 (just as an example)? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/js20b/eli5_how_military_units_get_their_numbers_like/ | {
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"this is probably better off in /askreddit than eli5",
"I always wondered why we only hear about the 82ond and 101st Airborne-the 83rd must be pissed!",
"It's largely random. In WWII we had the first, second, and third armies, but then you get reasons like:\n\n-SEAL Team 6: Actually the second SEAL Team, but we wanted the Russians to think we had more.\n\n-112th Airborne: Made up of 2 different units, something like the 50th and 62nd, couldn't decide whose number to take when they got combined, so they just added them.\n\nOther units were just split up and given \"the next number\" that wasn't being used and then became autonomous by circumstance, so they were reinforced and became their own unit. Really there's no single rhyme or reason to it.\n\nCharlie 3-07 sounds more like a callsign. Like the 7th crewman in the 3rd vehicle of Charlie platoon.",
"Some of these units were wiped out and others absorbed by other units that had not lost as many men. You don't have the resources to constantly change the numbers (repainting vehicles, new patches on everything, record-keeping continuity, etc) so the surviving units retain their old numbers. The rest were either killed off or had their numbers slowly reduced through attrition until the remaining members were dispersed to similar units.",
"It's actually quite simple. The military numbers divisions (10,000 - 15,000 people) as they're created. When they are deactivated, that number is simply dropped, but they keep naming new divisions counting up from the last number used.\n\nThe military used to use the same method for numbering regiments (3000 - 5000 people), but they stopped doing that during the Civil War when some states made their own numbers for regiments. Now I think the regimens simply decide on a number, I'm not sure.\n\nThe military will also combine regimens as needed into each division. So it makes the regimen numbers in the division seem random, because they don't renumber the regiment when it's placed in a division.\n\nEDIT: Not regimen, regiment.",
"It gets even more confusing when you start considering Aviation Units. The 2nd Marine Aircraft Wing hosts VMA-231, VMA-223, VMA-542 under MALS-14... VMA as it was explained to me stands for Fixed Wing Marine Attack Squadron and I have no clue where our numbers came from. MALS is Marine Aviation Logistics Squadron which kinda feeds us our intel and some of our 2nd level engineering. I never really questioned our numbering systems all that much but since you mention it... they make no fucking sense.",
"For the second part of the questions the 24th ID (like the 25th ID) started life as the 'Hawaiian Division' in the 1920s (consisting of troops from, or stationed in, Hawaii) - That division was split into two new divisions under the new 'Triangular' structure in 1941, and they were present when the Japanese bombed Pearl Harbor.\n\nThey fought right through WWII in the Pacific Theatre, ending up as a part of the army of occupation in Japan. They were the first US unit committed during the Korean War, served in Germany during the Cold Ware and Desert Storm in 1991. After that they became a training unit in the US, and were deactivated in 2006.",
"this is probably better off in /askreddit than eli5",
"I always wondered why we only hear about the 82ond and 101st Airborne-the 83rd must be pissed!",
"It's largely random. In WWII we had the first, second, and third armies, but then you get reasons like:\n\n-SEAL Team 6: Actually the second SEAL Team, but we wanted the Russians to think we had more.\n\n-112th Airborne: Made up of 2 different units, something like the 50th and 62nd, couldn't decide whose number to take when they got combined, so they just added them.\n\nOther units were just split up and given \"the next number\" that wasn't being used and then became autonomous by circumstance, so they were reinforced and became their own unit. Really there's no single rhyme or reason to it.\n\nCharlie 3-07 sounds more like a callsign. Like the 7th crewman in the 3rd vehicle of Charlie platoon.",
"Some of these units were wiped out and others absorbed by other units that had not lost as many men. You don't have the resources to constantly change the numbers (repainting vehicles, new patches on everything, record-keeping continuity, etc) so the surviving units retain their old numbers. The rest were either killed off or had their numbers slowly reduced through attrition until the remaining members were dispersed to similar units.",
"It's actually quite simple. The military numbers divisions (10,000 - 15,000 people) as they're created. When they are deactivated, that number is simply dropped, but they keep naming new divisions counting up from the last number used.\n\nThe military used to use the same method for numbering regiments (3000 - 5000 people), but they stopped doing that during the Civil War when some states made their own numbers for regiments. Now I think the regimens simply decide on a number, I'm not sure.\n\nThe military will also combine regimens as needed into each division. So it makes the regimen numbers in the division seem random, because they don't renumber the regiment when it's placed in a division.\n\nEDIT: Not regimen, regiment.",
"It gets even more confusing when you start considering Aviation Units. The 2nd Marine Aircraft Wing hosts VMA-231, VMA-223, VMA-542 under MALS-14... VMA as it was explained to me stands for Fixed Wing Marine Attack Squadron and I have no clue where our numbers came from. MALS is Marine Aviation Logistics Squadron which kinda feeds us our intel and some of our 2nd level engineering. I never really questioned our numbering systems all that much but since you mention it... they make no fucking sense.",
"For the second part of the questions the 24th ID (like the 25th ID) started life as the 'Hawaiian Division' in the 1920s (consisting of troops from, or stationed in, Hawaii) - That division was split into two new divisions under the new 'Triangular' structure in 1941, and they were present when the Japanese bombed Pearl Harbor.\n\nThey fought right through WWII in the Pacific Theatre, ending up as a part of the army of occupation in Japan. They were the first US unit committed during the Korean War, served in Germany during the Cold Ware and Desert Storm in 1991. After that they became a training unit in the US, and were deactivated in 2006."
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40sqo7 | why should one's beliefs impede another's rights, especially if the other doesn't subscribe to their belief system? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/40sqo7/eli5_why_should_ones_beliefs_impede_anothers/ | {
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"Christians believe being around gay people or being forced to serve them food in their restaurant is the same as \"being forced to accept homosexuality\". In Christianity, homosexuality is a sin punishable by death, no different from murder. \n\nAlso, they believe gay marriage or gay rights are special rights. They believe it is equal because no one should have the right to marry someone of their same sex.",
"It is unavoidable that if your \"rights\"... lets just say freedoms... are to be impeded in any way that this is done according to someones (presumably most peoples) beliefs. In other words, if you are forbidden from doing something, it's because of some belief that you should be.\n\nClearly, you and I should be forbidden from doing some things. Clearly high on the list are things that harm others directly, like murder. But this is forbidden because we believe it should be so.\n\nLower on the list are things that are forbidden because they are 'wrong'. We forbid cruelty to animals, even though they have no legal rights. I think we all believe this is as it should be, but that is only a belief, and has not always been so, certainly not in certain societies.\n\nI could go on, but the point is that belief of some kind is at the root of all restrictions or exhortations - including the desire to limit the influence of some beliefs, else you'd likely still be ruled by a king or other absolute ruler.\n"
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9bjjzh | plato's theory of forms and aristotle's criticism to it | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9bjjzh/eli5_platos_theory_of_forms_and_aristotles/ | {
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"Basically there's a place where there's a perfect form of everything that exists. Like a perfect chair or perfect cat or perfect pencil. According to him when we are born we are born with the knowledge of all these perfect forms but we forget as we get older so we live in an imperfect version of the perfect form world. In other words there are no new inventions we are just remembering. ",
"Both were wrestling with the human experience of the abstraction of ideas and terms for things in the world. E.G. we think lots of things are beautiful, so what is \"beauty\"?\n\nPlato argued that things like \"beauty\" were abstract concepts (and universal concepts) that exist independent of the things we'd describe as beautiful. E.G. \"beauty\" is a form, and \"a beautiful flower\" is a flower that invokes that abstraction.\n\nAristotle rejects this abstraction and says that beauty is an inherent attribute of the object and we can't talk about them independent of the objects themselves in any real sense. E.G. the idea that beauty somehow exists without us having any objects we'd describe as beautiful is non-sensical.\n",
"Little Kid: \"Dad, what's a dog?\"\n\nDad: \"Well, we have Buster at home. Buster is a dog.\"\n\nLittle Kid: \"Yeah, but what *makes* Buster a dog?\"\n\nDad: \"Well, he walks on four legs and is covered in fur.\"\n\nLittle Kid: \"Yeah, but so does our cat Oscar.\"\n\nDad: \"Yeah... well, Buster barks.\"\n\nLittle Kid: \"But bears walk on four legs, are covered in fur, and kind of bark. Are bears a type of dog?\"\n\nDad: \"No dingbat, bears aren't a type of dog. When I tell you to think of a dog you don't think of a bear do you?\"\n\nLittle Kid: \"No . . . but what if you shave Buster? Is he still a dog with no fur? Cause that's not what I think of when I think of a dog.\"\n\nDad: \"No, he's still a dog. He's just . . . different. Dogs just sort of have that dog-like quality to them. I guess dogs are just something where you know it when you see it.\"\n\nThis sort of illustrates Plato's Theory of Forms and Aristotle's critique. Plato was basically saying that when you're trying to define something, you ultimately will need to invoke a kind of knowing that isn't a matter of grasping a definition of one term by means of another terms, but of grasping the thing itself. In other words, the concept of a \"dog\" is an abstract universal entity that exists independent of dogs themselves.\n\nAristotle said yeah, but there must be some knowledge of the substance which is *in* the thing. There must be something *in* Buster, some type of dog-like quality, which makes Buster a dog."
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6a8tyt | why are videogame consoles and other electronics arranged in rectangular prisms rather than cubes? | Is there a direct reason for it? Is it more efficient/powerful or is it just for looks? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6a8tyt/eli5_why_are_videogame_consoles_and_other/ | {
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"They're based around circuit boards which tend to be flat and not square. Making a cube would either result in a *giant* cube, forcing you to make your circuit board really tiny or splitting the electronics into multiple square boards & adding some sort of interconnect between them, none of which are ideal solutions.\n\nFor one example, [here's the inside of an XBox 360](_URL_0_)."
]
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3vlqtr | why do veins swell when you constrict your blood flow? | When I put squeeze my arm just below my elbow, the veins on my forearm swell considerably. Why is this? Wouldn't you just be restricting blood from entering your arm to cause this? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3vlqtr/eli5_why_do_veins_swell_when_you_constrict_your/ | {
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"Blood flows out from your heart along arteries, and back to the heart along veins. Blood pressure is very high in the arteries, and low in the veins - it's the drop in pressure that carries it through your circulatory system.\n\nSo, grab your arm above the elbow, and what's happening? You're constricting the whole area, raising the internal pressure. Think of the arteries, running deep down in the tissue, as high pressure hoses. You're squeezing them, but that has little effect. Meanwhile, the veins are made of floppy tissue that carried blood under low pressure, so your grip is enough to collapse them.\n\nThat means that blood is flowing out to the arm, but having trouble coming back.\n\nAs the veins are only used to holding low pressure their walls are weak and flexible. When all that extra blood has to go somewhere, they balloon out and fill with it."
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76qkf8 | what is border adjustment and how will it let trump force mexico to pay for the wall? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/76qkf8/eli5_what_is_border_adjustment_and_how_will_it/ | {
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"I'm not an expert. But as I understood it, the border adjustment simply means import/export toll (I don't know the English word; I mean the fee you or a company has to pay to be allowed to transport goods to another country) is changed. Less import taxes for US Companies, and more export taxes for Foreign (Mexican) companies. This way, rather than paying the price of the wall directly, Mexico will \"pay\" through their companies paying import tolls to the US. Of course, that could mean Mexican Companies shift their export to other countries than the US, should that be possible. I can't give a guarantee that this is correct."
]
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2drcgc | the rick perry indictment | Why is he being accused of corruption? Who is Lehmberg and is she a nutjob? Was his refusal to fund the cancer research agency illegal? How are Texans responding do this, on both sides of the aisle? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2drcgc/eli5_the_rick_perry_indictment/ | {
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"Lehmberg is an elected district attorney. As such, she cannot be fired directly by Governor Perry. Lehmberg was charged with a DWI back in 2013, did some jail time, and successfully defended her position in a civil suit. Governor Perry does not want Lehmberg to remain in office, so he threatened to veto $7.5 M in funding specifically set aside for a public corruption unit that operates out of Lehmberg's office, unless she stepped down. She did not, so Perry vetoed the funding.\n\nA complaint was filed against Governor Perry for this and presented to a grand jury, who indicted him on charges of abuse of an official capacity, and coercion of a public servant."
]
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677ouo | how do shows like last week tonight identify clips for a clip montage? | Tonight's Last Week Tonight ended with a montage of Bill O'Reilly that had sexist and racist clips of him from the past 20ish years. I realize it wouldn't be hard to find such clips in this particular instance, but they do this every week. I doubt they have a team of people watching episodes to find content. So, how do they do it?
Do they have access to transcripts for every show ever and simply search for keywords? Is there a company that archives and sells these transcripts? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/677ouo/eli5_how_do_shows_like_last_week_tonight_identify/ | {
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"text": [
"Studios have library / archive services that will sell you clips to use. For example, [NBCUniversal Archives] (_URL_0_) has clips from their news shows.\n"
]
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4gtwg5 | how does a thermal explosion cause a human to get knocked back, as often seen in action movies? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4gtwg5/eli5_how_does_a_thermal_explosion_cause_a_human/ | {
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"Movies aren't always representative of real life. Action movies even less so.\n\nOf course, it's possible for an explosion to knock people back. Because of the rapidity with which explosion take place, they almost always create a shock wave. The problem with being knocked back with the shockwave from a thermal explosion, however, is that the shockwave is likely many thousands of degrees. Of course, only being in contact with it for a short time, you wouldn't necessarily be burnt to death (unless it was a *really* hot bomb), but it certainly wouldn't be as clean as movies lead us to believe.",
"Its called a shock wave; I'll try my best at an ELI5. If you push on a solid object, obviously the other side of the object moves at the same speed. When you push on liquid, like when you're swimming, the little bits of water push on each other and if you were close enough to where it was being pushed, you could feel that too. You don't feel the push as strongly because the little bits of water are able to slide around each other. You can push on air the same way, but the little bits of air move around each other more easily than anything else, so the push fades pretty quickly across distance. \nWhen there is an explosion, the air is pushed so quickly that the other bits of air in front of it are not able to move out of the way, so it's much more like pushing on something solid. If someone is close enough they'd feel that push. \n(My first attempt at one of these, hope I helped)",
"Bona fides: among a few things in life I wrote a book that was adopted by the FBI National Academy and the US Army Bomb School as a textbook, did two tours Afghanistan, for whatever that's worth to the perceived accuracy of what I'm about to say.\n\nThe question seemed sincere so I'll be sorta specific. Excuse any bomb-geekiness. While there is a term 'thermal explosion' or thermal runaway, in the layman's language the word 'thermal' revers to one of three components of a bomb blast: heat, shock and fragmentation.\n\nHeat is simple to understand. At the heart of a conventional blast a chemical reaction cranks out a helluva lot of heat. To put that in perspective, at the Oklahoma City bombing, streetlights down the block were melted. But heat alone won't throw you; it will burn or ignite stuff.\n\nFrag is easy as well: every solid thing the bomb was made of, and every solid thing the bomb blows apart, goes flying at 'way-past-bullet-speeds.' Frag can be tiny slivers of metal, rock or wood, or in the case of the detonation of the USS Grandcamp, a piece of frag would include the ship's 10,000+ pound anchor that flew about half a mile. There is a technical difference between fragmentation and shrapnel, but that goes into geekiness for another discussion.\n\nShock: so imagine doing a cannonball in the pool. You hit the surface of the water and your body in the blink of an eye moves, or 'displaces' a whole lot of water, shoving it out and away from you in all directions. I will skip comparative compressability of water and air but for simple analogy say that in an 'air cannonball' if you froze time at the moment of impact, the air shoved away is moving faster than the air an inch, or a foot, beyond, so the moving air compresses into the space along with the still-stationary air (remember, this is like mili-second type speeds). What you get is a hollow ball of compressed air. So think about the \"thickness\" of the hollow ball as this expanding shockwave that is racing out. In the case of C4, it is racing out at about 26,000 feet per second. That's where the 'guys get thrown in movies\" effect is supposed to come from, but reality is a bit uglier. Here's the ELI5 on why:\n\nIf you fired a high powered rifle, lets say a 50BMG, the bullet leaves the gun barrel at roughly 3,000 feet per second. If you set off a big explosion 100 yards BEHIND the rifle at the exact same instant, would the explosion eer catch up / pass the rifle bullet? Yep, in just a shade under 0.005 of one second (and /r/physics redditors, I am skipping deceleration factors, exponential degradation, etc....) Point being, since an eye blinks in about one-third of one second, quite literally \"in the blink of an eye\" the explosive shockwave a football field away would blow by you. That is so freakishly fast that a living body, which is not a solid but a bag of solids, semi-solids and liquids, cannot accelerate uniformly to \"surf the wave\". So parts of the body catch the wave and race off while other parts get left behind. People can go from being people to being parts, to being, hm, just mulch, sometimes just being gone.\n\nPlenty of video on the subject, here is a decent one _URL_0_ skip to about 30-40 sec and look for the curved \"haze\" just outside of the obvious orange parts of the explosion. That is the shockwave.\n\nMay be more than you wanted but I hope it fills in some blanks."
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4fa173 | how broadcasters get such good sound of professional athletes while they are on the field. | Do they mic their helmets? Or do they have mics strategically place around the ice/court/etc? Fascinating imho. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4fa173/eli5_how_broadcasters_get_such_good_sound_of/ | {
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"The use [parabolic microphones](_URL_0_). They put a directional microphone at the focal point of a big bowl, and it makes it ultrasensitive towards sounds from a particular spot. ",
"One way is with those microphones that have parabolic dishes directing the sound into the microphone at the focus point. You can see them being used in the sidelines. Sorry, I'm not sure what they're called."
]
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1j72c7 | why is it so hard to find alcohol that doesn't taste...like alcohol? you'd think someone would make a killing off of 40% koolaid-flavoured alcohol. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1j72c7/eli5_why_is_it_so_hard_to_find_alcohol_that/ | {
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"You can add whatever flavorings you want, but it still has alcohol in it.\n\nThat being said, properly aged alcohols mellow out in flavor. Top shelf, 30-year-old whisky tastes nothing like a $20 bottle from Walmart. If you're really looking for something light, I would personally recommend trying Chopin Vodka or Domaine de Canton.",
"When alcohol doesn't taste like alcohol and has a more welcoming flavor, like your Kool-Aid example, nothing good would come of that night of drinking. It would possibly cause the drinker to go far beyond their limit b/c of the good flavoring and alcohol poisoning is a real thing. Straight on the rocks keeps me from drinking more than 2.",
"It's an acquired taste. Eventually, you will like the taste it alcohol, with reason. Then you won't want an alcoholic drink that doesn't taste like it. That's why they don't make it.",
"Haven't you ever heard of flavored vodka? Tastes like candy. Especially caramel vodka, thats some good stuff.",
"If you like something sweeter that doesn't taste like alcohol, but can still get you drunk, try a stronger cider! I never used to like alcohol then someone intro'd me to cider and I love the stuff! \n\nAnd if you want something stronger, find a flavoured gin, my personal favourite is sloe gin! Take a pint glass and pour about 2/3 inches of it into it, then take either lemonade or a lemon flavoured alchopop and fill the rest of the glass with it, the result is you taking around 3 shots of fairly high percentage gin whilst only tasting lemon! I used this to get very drunk, very quickly one night and lasted about 2 hours.\n\nSorry for not answering your question, just providing some alternates! :)",
"older people like tend to start liking bitter stuff over sweeter"
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33a5ua | does true randomness exist in the universe? if i replayed the universe exactly the same from the start, would it be exactly the same? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/33a5ua/eli5_does_true_randomness_exist_in_the_universe/ | {
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"We don't know, is the simple answer. Our best current guess appears to be \"yes, it does\", but there are theories that get around it at the cost of losing common assumptions.",
"Does true randomness exist in the universe?-Yes. At a quantum level randomness happens all the time. Would the universe be exactly the same if we re-ran it? Probably not, if our quantum theories are correct, although not everyone agrees. Whether we could notice the difference is anyone's guess."
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eit86m | how are wild plants domesticated? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/eit86m/eli5_how_are_wild_plants_domesticated/ | {
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"It's a very very long process, where farmers basically just breed plants with traits they like, in an effort to make those traits more prevalent over time.",
"Same as animals essentially. We find a plant with desirable qualities and then use selective breeding to essentially modify their genome into a new variety/sub-species, or a new species entirely, over time.\n\nTake your corn/teosinte example. Some time around the agricultural revolution some early human who liked to eat teosinte took some seeds and began cultivating it, propagating the plants that had the best tasting/yielding fruit. Then after a while of this selective breeding it ‘evolved’ into modern or ‘domesticated’ corn. \n\nSame as with dogs and wolves essentially. Separate a small group from the larger population and it will eventually develop distinctive traits and dna. This is the ‘theory’ of evolution."
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1nqm4f | why does my heart rate drop when i exhale? | I've been checking my pulse a lot lately and I just noticed this. Whenever I exhale, my heart rate plummets to like half the normal rate, then goes right back to normal when I inhale again. Why does this happen? Is this normal? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1nqm4f/eli5_why_does_my_heart_rate_drop_when_i_exhale/ | {
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"It's called sinus arrhythmia, and it's perfectly normal and benign, especially in young people. I have it too.\n \nI'm a little fuzzy on the details, but I believe it's because the expansion of your lungs as you inhale puts pressure on a nerve that controls heart rate."
]
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3lx9ao | the difference between unlawful and illegal. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3lx9ao/eli5_the_difference_between_unlawful_and_illegal/ | {
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"They're pretty much interchangeable. You might define \"illegal\" as \"forbidden by the law\" and \"unlawful\" as \"not permitted by the law\", but they boil down to the same thing. \"Illegal\" also tends to be used more for criminal law, while a civil wrong is more likely to be described as unlawful, but that's not a clear cut rule."
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2rmss0 | lasers and mirrors | So mirrors are used to route laser beams. Mirrors are just reflective surfaces, like polished silver or aluminum. Can a good mirror be used to "deflect" a very powerful laser? Like super powerful ones used in crazy science labs that consume megawatts of power...are even those rendered harmless (so to speak) by a simple mirror? Is there any theoretical limit to this? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2rmss0/eli5_lasers_and_mirrors/ | {
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"text": [
"If a mirror reflects 90% if light that means it absorbs 10% of the light. If 10% of a laser is enough to burn a thing then the mirror burns. There is no 100% reflective mirrors. "
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ba1c5l | why do home thermostats have a "heat/ cool" switch? why can't you simply set a range and have it automatically determine whether to use the ac or the heater? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ba1c5l/eli5_why_do_home_thermostats_have_a_heat_cool/ | {
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"There are actually thermostats that have an 'auto' mode that does switch from heat to cool and vice versa. Typically, only higher end thermostats have this, though. This is because it takes more advanced temperature sensors to allow an 'auto' function to work. \n\nSay it's summer and you have the thermostat set to 'cool', and 78 degrees. The AC blows cool air into the house, but it might reduce the temperature to 77 degrees. This is typically intentional, to increase the time between the system turning off, then on again as the temperature rises from outside heat. In this case, if you were in an 'auto' mode, the furnace would kick in, which would not be desirable in the summer! \n\nPremium thermostats that do have an 'auto' switch for heat and cool have extra setpoints or criteria before allowing the system to shift modes. For example, some use the date to determine what month it is, to prevent the furnace from being used in the summer. Otherwise, it would be 'turn AC on if temperature hits 80F, and furnace if it hits 70F' or something like that. ",
"Simple reason, it is a cheaper model. My thermostat has an auto setting where I can set a high and low. Depending on the temp it will kick on heat or ac to stay in the proper range.",
"I have a Honeywell thermostat with an auto function. It allows a range of temps and will automatically switch from heat to cool. However, I find that even with the minimum spread of temperature allowed by it, the temperature swing is too much for me to be comfortable. So I still use it manually.",
"Because most people want different set points. For example you might want to heat (up) to 20°C and cool (down) to 26°C. Between those two points you want neither cooling nor heating."
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2qc1jz | why are data caps for mobile phones still so small? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2qc1jz/eli5_why_are_data_caps_for_mobile_phones_still_so/ | {
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"Phone companies are greedy so they set data limits low to either a) make you use less of their product than you normally would or b) pay more for using your natural level of usage.",
"For those using t-mobile and are paying at least 3gb data monthly, u should be able to carry over your unused data for the next month. Not sure if it started now or at a given time, I'll pull the text that they sent me... ",
"This ELI5 may shed further illumination, especially if you are comparing home plans to mobile. _URL_0_",
"Lack of competition in the marketplace. Behemoth corporations have taken over and the incentives for innovation go down.",
"The reason the data cap on your plan is so small is that you purchased a plan with a low cap.",
"It's an arbitrary number. Similar to the number of letters in an SMS message.\n\nThe concept of a 'data cap' is meant to limit the quantity of data that flows through a network, but that's not really how networks work. Networks send data to a destination, then forget about the data. That destination may be a temporary storage server if your phone is off or something, but it is still a destination. \n\nWhen you're downloading something over your phone (like this reddit thread) your phone requests the data from the server, and the server spits it back at your phone. Done. Boom. You have what you wanted, the network moves onto something else.\n\nNetworks have a data capacity, but this is not a *storage* capacity, this is a *transmission* capacity. A typical sleepy township cell tower will have at least a gigabit [backhaul](_URL_15_) connection to the network provider so that it can provide cell service. When you try to download something you use up a bit of that bandwidth.\n\nRemember, it's not a big truck. [It's a series of tubes.](_URL_11_) As you use the tube, it fills up. Everyone uses the tube? Tube's full, new requests have to wait until there is space in the tube. Instead of getting a message saying \"Tube's full bro, wait a bit\" the network will slow everyone down a bit to cram your request into the pipe.\n\nNow, instead of a sleepy little town let's talk about New York City. If we look[ into the books of not-too-distant history](_URL_10_) we will remember that [AT & T had a bit of a problem when the iPhone](_URL_7_) was [unleashed upon their networks.](_URL_5_) Suddenly, people were sharing *pictures* and *videos*! They were browsing the *internet* and they weren't business customers!! Madness roaming about the streets! And, most importantly, their network **was not prepared for this**.\n\nDemand was unprecedented and their network was rapidly brought to its knees in major cities. As they threw everything they had at the major cities the local towns began to suffer too. Major networks got everything situated for the time being, but they're still playing catch-up in a lot of areas.\n\nSo now that the iPhone is out and about everyone is filling the tubes all the time always. [New York Times chimed in](_URL_14_) with a lovely long article really detailing the issue, and there were other companies suggesting that consumers [do the responsible thing and control their data guzzling.](_URL_0_) Use WiFi when watching YouTube, for instance.\n\n(Side note: I just want to point out a **lovely** quote from that NYT article: \n > The company has also delayed bandwidth-heavy features like multimedia messaging, or text messages containing pictures, audio or video. It is also postponing “tethering,” which allows the iPhone to share its Internet connection with a computer, a standard feature on many rival smartphones. AT & T says it has no intention of capping how much data iPhone owners use. \n\nOf note this was actually one of the first big intentional violations of net neutrality. A system called Quality of Service, or QoS, was used to make raw data, emails, etc. more important to the network than multimedia (music, youtube) on the network. This helped, a bit, somewhat, because important emails could get through when too many people were watching cat videos in wifi-less coffee shops. The line about not capping data actually plays right into what I'm talking about)\n\nNow, what do we do about this? Well, AT & T introduced [QoS](_URL_13_) and data priority, which let important things through when the tubes were full of unimportant traffic. This somewhat helped people get work done, but the root issue was the tubes were full and it was [expensive to put new tubes out there.](_URL_2_)\n\nNow, where did the caps come from?\n\nWhile networks do not store, they do have quantities transferred. You see this as a 2GB cap on the data you can use in a month. AT & T sees this as 1 cent per Terabyte transmitted to Cogent. That's an extremely simplified [peering rule](_URL_6_), but it works for this discussion. In order to talk to someone's server that is on Cogent's network when you're on AT & T's network, at some point along the line your data needs to go from one network to another. That's peering.\n\nSometimes this peering is free (like Cogent). Sometimes this peering is not (like Verizon, I think). When it is not, it costs the company money to transmit data that direction.\n\nSo the network providers already have a concept of paying for data transmission rates. They pay each other for data going back and forth (called transit), this is not a new concept. Originally you could get data modems for the early cell networks, and you paid per *kilobyte* and later megabytes. [Satphones will still do this.](_URL_12_) So the raw idea of \"pay for a block of data\" was something that the telcos were already familiar with. \n\nThat's where the idea *came from*, but *why*? Well, they needed to reduce network load. \n\nIf you want to reduce network load then you throttle network connections. Block multimedia due to \"heavy load\" during peak hours, maybe do some on-the-fly calculations on what the network can handle and modify what people are allowed to connect to on the fly. This makes for *extremely* pissed off users. A slowly loading website is one thing, \"Cannot load: Network capacity reached\" is another thing entirely. So that's out as a solution. Temporary at best.\n\nNext up is tiered access. Pay for Facebook, Twitter, etc. at one rate, and at the next rate get access to YouTube etc. Violates net neutrality and gets the FCC up your butt. That's out.\n\nIncentive wifi use. Your average smartphone user doesn't really care (unless they're watching their data use closely) where their data comes from, so you need to make this an incentive. Generally, plans will let you make \"FREEEEEEEEEEEEEEEEE\" calls over wifi and of course free data these days. Most phones have an ability to constantly seek, connect to, verify connection through and then use any available wifi networks with open internet. This can cause problems (\"Why is my call dropping when I walk past this coffee shop all the time?\") but also gets people who don't care and don't watch their phone's wifi connection to get the hell off your wireless network when they want to watch a stupid puppy. This took a few years to implement, but it's what they're doing now.\n\nForce people to care about how much data they use. Thiiiiisss is where the caps originally came in. Some manager somewhere asked the sysops \"Wtf do we do about all of these youtube videos!?!\" and the sysops replied \"Uh, block youtube.\" Management vetoed this because the big selling point was cat-videos-on-the-go right in your pocket.\n\nSo then they said \"[Wait, we could just introduce a data cap.](_URL_8_)\"\n\nHaving something be unlimited makes you not care about it. Having a resource be limited (scarce) makes you preserve it. Having it be an *allowance per month* makes you budget it, and having it be expensive when you go over (or throttle to shit, like T-Mo) makes you want to not go over.\n\nThis means you smear your 5GB (or 2GB, or 4GB, etc) out over the course of a month rather than just watch youtube videos on the bus every day.\n\nNow read this [Bloomberg BusinessWeek article](_URL_1_) about it. Here's a BoingBoing article from a similar time period. Listen to how *happy* they sound about this idea. Data caps were a financial incentive to use significantly less data, and at the time people did use significantly less data. Note how there's no mention of actual data amounts anywhere in those articles? Back in 2009 the average iPhone user[ used 400 Megabytes of data a month,](_URL_3_) compared to other \"[smartphones](_URL_9_)\" of the time period using closer to 80 MB a month.\n\nThese days that's *nothing*. You can eat through 80 MB on a single day with a few youtube videos, some Reddit image browsing and a little bit of MMS images shooting back and forth. I'm on Sprint, and last month I used north of 15 GB of data. It's easy to do in our high resolution always connected world these days. Back then, it was a non-issue.\n\nThe Slate article I posted earlier is talking about $10/100MB. That'd be madness in our day and age ($200/2GB) so we're pretty happy when they ask for less than 50 bucks a month for this generous 2GB package. In [2010 AT & T released their tiered data structure](_URL_4_) which was the genesis of the current 2GB trend in wireless plans. Then they sunsetted the unlimited plans. Now, people were monitoring their data use, badgering their coffee shops to install wifi and generally giving the internet tubes significantly less of a beatdown. This helped, and today NYC has wireless coverage that isn't completely terrible.\n\n(Cont)",
"Because people happily pay for it.\n\n\nThey may use the \"we can't have everyone maxing it or nothing would work\" excuse."
]
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[],
[],
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"https://www.reddit.com/r/explainlikeimfive/comments/2pnw7a/eli5_why_are_there_unlimited_data_home_internet/"
],
[],
[],
[
"http://www.maclife.com/article/feature/iphone_app_data_hogs",
"http://www.businessweek.com/technology/content/may2009/tc20090515_773194.htm",
"http://www.att.com/gen/press-room?pid=4800&cdvn=news&newsarticleid=27069",
"http://usatoday30.usatoday.com/tech/news/2009-06-16-iphone-att-3gs_N.htm",
"http://www.att.com/gen/press-room?pid=17991&cdvn=news&newsarticleid=30854&mapcode=",
"http://www.technologizer.com/2009/06/09/atts-network-problems-arent-just-in-big-cities-anymore/",
"http://en.wikipedia.org/wiki/Peering",
"http://www.slate.com/articles/technology/technology/2009/10/the_iphone_is_not_an_allyoucaneat_buffet.html",
"http://appleinsider.com/articles/09/05/18/repeat_att_may_introduced_20_limited_iphone_data_plan",
"http://en.wikipedia.org/wiki/BlackBerry_Bold",
"http://www.applegazette.com/iphone/the-iphone-is-useless-in-new-york-city/",
"https://www.youtube.com/watch?v=f99PcP0aFNE",
"http://en.wikipedia.org/wiki/Iridium_Communications",
"http://en.wikipedia.org/wiki/Quality_of_service",
"http://www.nytimes.com/2009/09/03/technology/companies/03att.html?_r=1",
"http://en.wikipedia.org/wiki/Backhaul_%28telecommunications%29"
],
[]
] |
||
3ojtxw | what do underwriters for insurance companies do? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3ojtxw/eli5_what_do_underwriters_for_insurance_companies/ | {
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"Underwriters are the people actually taking on responsibility for the insurance claim; the people who will actually pay. \n\nIn a lot of cases this is the same company, but if for instance you use an insurance **broker**, that's where things would be different, because they would search around for the best company for whatever it is you need, and choose them on your behalf. \n\nSay for example you use the insurance broker, \"No Crash Insurance\". They might shop around and find the best deal for you is with \"Union Direct\". In case it wasn't obvious, these names are made up for the purposes of this example.\n\nIf you accpted that, then your insurance would then be through \"No Crash Insurance\", underwritten by \"Union Direct\".\n\n"
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||
3dzmmm | why does wikipedia cost so much to maintain if most of the people work for free editing the pages? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3dzmmm/eli5_why_does_wikipedia_cost_so_much_to_maintain/ | {
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"The Wikimedia Foundation, the parent organization of Wikipedia, employs a lot of people to maintain the site and the hosting. That isn't free.",
"The traffic Wikipedia endures on a daily basis is what drives the cost up so high. The actual size of the website is pretty easy to maintain.",
"Wikipedia gets almost 500 million unique visitors per year. And each unique visitor might view dozens of pages.\nEven if it only costs one cent to serve all the pages a single person might view in a year, that's still five million dollars worth of bandwidth and hosting. And that doesn't even take into account the paid employees, technical troubleshooting and upkeep, etc."
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2n374l | why do certain grapes make your mouth dry when you bite into them? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2n374l/eli5_why_do_certain_grapes_make_your_mouth_dry/ | {
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"Because they have [tannin](_URL_1_) in them. Tannin is an [astringent](_URL_0_) compound, which means it binds to certain proteins in your mouth and tends to shrink and constrict body tissue.",
"They have a lot of tannin in them which creates the sour pucker your mouth flavour that you get from some dry wines. The reason for this is that tannin is not present in any food which gives us nutritional value and thus our bodies evolved to give the dry mouth signal when eating something with a lot of tannin. Obviously now days we ignore that reflex of the body and continue to drink that glorious scarlet liquid. I am about to tuck into a bottle of Gewurztraminer and a small cheese board. \n\nEdit: Sorry I realised I was wrong, it's not that tannin is in things with low nutritional value, it's that tannin makes your digestive system less effecient by bonding with the digestive juices which in turn decreases the amount of nutrition gained from food eaten whoile the tannins are present in the body. "
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"http://en.wikipedia.org/wiki/Astringent",
"http://en.wikipedia.org/wiki/Tannin"
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||
ezcbpa | what goes into a whiteboard paint that makes it finish like a dry erase board and not a normal paint? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ezcbpa/eli5_what_goes_into_a_whiteboard_paint_that_makes/ | {
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"Dry/wet erase markers are basically just an ink that dries into something that doesn't stick well to a surface - dry erase forms a film, wet erase is water soluble. \n\nThis works on any surface, in theory - you could use dry erase on rough wood, except that it would seep into pores and cracks and other rough spots before it dries, making it really hard to remove. \n\nOn the other hand, if you use it on something smooth and \"non-porous\" (which means it has no holes, even tiny tiny ones), it's very easy to wipe off the surface. \n\nSimilarly, you can use high gloss tile as a white board, but if you use tile that isn't high gloss, you will have a very hard time wiping it off. \n\nWhiteboard paint is mostly just a paint that doesn't have those tiny holes. It's very very smooth, which makes it more shiny. It also has chemicals that make it have high surface tension (like a water drop) so that it dries nice and smooth, unlike normal paint that's designed to not hold together as well, making it flow into cracks better."
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3vtiit | government encouraging marriage | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3vtiit/eli5government_encouraging_marriage/ | {
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"It's not so much marriage that they're encouraging as being a stay-at-home spouse. There's only really a tax benefit if one person is making most of the money. If the two people make even close to the same amount of money, they pay less in taxes by filling separately. "
]
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3l3qvw | why are music apps like spotify so much more ad intensive on phones than their computer counter parts? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3l3qvw/eli5_why_are_music_apps_like_spotify_so_much_more/ | {
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"It's rather simple really. Consider a billboard on the side of a road. If the road is a highway with many cars driving past, the billboard will be much more effective than a billboard next to a small farm road. The internet is the same, people tend to advertise where the most users are. Advertisers have tools that tells them how much traffic they get from mobile devices vs their computer counterparts.\n\nThe simple fact is most users are digesting content on a mobile device, which they have with them all the time (e.g. smart phone) as opposed to a desktop computer where they will only spend time on occasionally. By running more ads on mobile, advertisers are reaching more people than they would on desktop.",
"Not really about the number of users at all. Look at television- a show with 100k viewers on some deep cable channel has the same amount of commercials as a show with 2 million viewers on a more popular channel. Less users just means lower cost of advertising, but there's not a significant enough \"lack of advertisers\" to not be able to play you an ad.\n\n\nThe reason there are more ads on mobile is because it costs more to play the songs. Music services such as Spotify pay money to the rights holders (a small number of music publishing companies) to be able to play you the songs that they own. Those music publishing companies have decided that, for whatever reason, they will charge Spotify and other streaming services more money to play their songs on mobile devices vs. desktops.\n\n\nTherefore, to offset the extra cost, Spotify (like all companies) passes that cost off to you in terms of more ads.\n\n\nA few years ago, Spotify (non premium) was just like Pandora in that it would only stream you songs in a discover / radio way on mobile, where you could only choose a starting point and had no real control over what actual specific songs you would be hearing. Then Spotify renegotiated contracts with the music publishing companies allowing them to steam you artists and playlists on mobile, as long as it was on shuffle and more than x number of songs (I think the number was 20). \n\n\nTL;DR\n\n\nIt's not about number of users. It's about how much it costs for streaming services to secure the rights to songs, and it's more expensive on mobile devices so they need more ads to pay for them. "
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4ovv0g | why are there so many more 'simple' medical procedures available for humans than there are for animals? | I am not sure if the answer is more about lack of willingness or lack of resources...
I mean stuff like;
Say a person was hit by a car and had some internal organ damage. For a human that requires bed rest and maybe some minor surgery. For a cat/dog, it requires euthenasia, why?
In the same vein, if a person becomes paralysed e.g. from the waist down, they get a wheelchair. An animal gets death? Where are all the kitty wheelchairs?
I understand not operating on an old animal, in the same way an old person might sign a DNR, but why are so many young animals put to sleep for relatively small things? Maybe the vets of reddit can shed some light :)
I ask because my 1yo cat was hit by a car in April, something must have severed spinally because both back legs were paralysed but apart from that no other external or internal injuries. We had to have him put down :( RIP Strider. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4ovv0g/eli5_why_are_there_so_many_more_simple_medical/ | {
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"Most animals don't have insurance. There are procedures for a lot of stuff, but not everybody can or wants to pay $5,000 when a cat & dog can be replaced for nothing.",
"Mostly it's money. Most people simply can't afford to spend multiple thousands of dollars on a pet.\n\nThe other big problems is that animals cannot take care of themselves. You can't prescribe a horse bed rest, because it's a horse and it isn't going to rest unless you keep it doped to the gills. Seriously injured animals are just not nearly as likely to recover a good quality of life as humans.\n\nIt also helps to remember that as animals go, humans are incredibly robust. We are really, really good at taking a beating.",
"It depends on the owner and the vet to be honest. A cat with two paralyzed legs can survive you can adapt two wheelers for it ( like a tiny wheelchair) if you take proper care of it but it takes time and money and owners are not willing to do that for their pets. I wouldnt have put that cat down by what you are saying, only if asked. But also its not only the paralyzed legs that is the problem your kitty would've been incontinent, would've been more prone to bladder infections, his bladder would need to be expressed, like I said its up to the owner and what is willing to do for its pet so that is why sometimes the humane thing to do is euthanize them because even tho you love them you just dont have the time to care for them. Im using your case as an example tho in some cases pets just dont recover and they live in constant pain so the better thing for them is to put them down. \n\nAnimal's bodies simply cannot handle stress the way we do. \n\n\n",
"my coworkers dog got hit by a car. his dog's medical bill currently stands at $25,000. the dog's alive but owner is about to go bankrupt. "
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1hj6xf | what is the difference between fat, saturated fat and trans fat? and what is the sudden big deal about trans fat? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1hj6xf/eli5what_is_the_difference_between_fat_saturated/ | {
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"Fats are a type of carbon-chain that your body uses for energy. Carbon atoms are able to form up to four bonds with other atoms.\n\nSo a saturated fat is where the carbon chain is entirely single-bonded. The 'saturated' part comes in because most of those carbon bonds are bonded to hydrogen atoms; in fact, the most number of hydrogen atoms the carbon chain can hold (thus 'saturated' with hydrogen atoms). Studies have shown that saturated fats are associated heart disease and other vascular issues. Saturated fats typically come from animals, and typically solid at room temperature as the single-bonded carbon chains are very flexible and can tightly pack with each other.\n\nUnsaturated fats have one or more of those single carbon bonds have been changed into a double-bond. This removes some of the hydrogen atoms from the chain as a result. Mono-unsaturated means only carbon double-bond has been formed, but you can have poly-unsaturated which can have several carbon double-bonds in the chain. Unsaturated fats are typically from plant sources, and are usually liquid form at room temperature because the double-bond is a much more rigid bond and causes the carbon chain to take a sort of 'kinked' shape.\n\n[Here's a picture of the two types just for a comparison.](_URL_0_) Note the way the unsaturated chain is bent at the double-bond, that will be important in the next section.\n\nTrans-fats are a type of unsaturated fat, and studies have also linked these to heart disease to an even greater degree of severity than saturated fats. As I said earlier, unsaturated fats are typically liquid (more bonds = more likely to be liquid at room temperature), and humans usually use solid fats for cooking. As such a process called 'hydrolyzing' which adds hydrogen atoms to the fat chain, removing some of the double-bonds so that the unsaturated fat can be made into a more marketable form.\n\nNow remember that 'kink' I mentioned in the unsaturated fat? Well when a double-bond is made, it can take one of two forms (called isomers), known as either trans- or cis- arrangement, which basically describes how the atoms are arranged relative to each other. Cis- arrangements are the common form in nature, but the artificial hydrolyzing process creates trans- isomers of the fat.\n\nHere's an image of a [trans](_URL_2_) compared to a [cis](_URL_1_) unsaturated fatty acid. Both have the same number of atoms, but vastly different shapes, and this geometric arrangement impacts how they interact with the body.\n\nThe exact mechanisms that make trans-fat unhealthy for you aren't exactly known, but one leading theory is that the body simply doesn't have the enzymes to breakdown trans-fats as they are artificially created. This is partially supported by another study that found naturally occuring trans-fats that did not seem to carry the same health risks (as they were naturally occur, thus creatures evolved ways to break them down, as opposed to our artificially created trans-fats).\n\nNot a nutritionist or a science major, so I may have glossed over some important details, but I think I got the basics covered.",
"This answer assumes some knowledge of atoms and molecules, and obviously there are more complex explanations. But the short version is that saturated fats and trans fats are bad, mmmkay?\n\nFat is a type of macronutrient - our body can burn fat molecules for energy, the same way it can burn protein and carbohydrate molecules. Fat molecules are mostly made of chains of carbon atoms, with hydrogen atoms bonded to them.\n\n[Saturated, monounsaturated, and polyunsaturated fat](_URL_0_) refers to the chemical structure of the fat molecule. Saturated fats have the maximum number hydrogen molecules bonded to every carbon atom (they are *saturated* with hydrogen), but unsaturated fats have one (mono) or more (poly) double bonds between carbon atoms somewhere along the chain, which means fewer hydrogen atoms.\n\nThe more saturated a fat is, the more likely it is to lead to an increase in the proportion of LDL ('bad') cholesterol in your blood, and contribute to coronary heart disease. Unsaturated fats are more likely to increase the proportion of HDL ('good') cholesterol.\n\nTrans fats are a special type of *unsaturated* fat, and are almost exclusively man-made. The 'trans' part of the name refers to the arrangement of the atoms around the carbon atom. Usually the hydrogen atoms are on the same side of the carbon atom (the *cis* configuration), but in a trans fat they are on opposite sides (the *trans* configuration). The outcome is that trans fat molecules act like even worse versions of saturated fats, despite being unsaturated.\n\nIn 2002 [The US National Academy of Science concluded](_URL_1_) that there is no safe level of consumption for trans fats. Every gram of man-made trans fat you eat contributes to factors that can lead to your early death."
]
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"http://upload.wikimedia.org/wikipedia/commons/b/bc/Elaidic-acid-3D-vdW.png"
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"http://en.wikipedia.org/wiki/Fat#Saturated_and_unsaturated_fats",
"http://en.wikipedia.org/wiki/Trans_fat#Nutritional_guidelines"
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||
1uyn5v | what sound properties do different musical instruments have different from each other? | This has always baffled me and I never got a real answer for it.
Light waves have a frequency and an amplitude. The frequency determines the colour and the amplitude determines the brightness (I'm only taking the visible spectrum into account). That's understandable enough.
Sound waves also have a frequency and an amplitude. This time the frequency determines the pitch and the amplitude determines the loudness. But then, how do different instruments, or different words for that matter, all sound unique to us? A violin and a piano playing the same note still sound very different from each other, and the same goes to different spoken words. I suspect that the real reason is that each instrument produces a lot of different waves at different frequencies, which when added together can be heard as a specific sound. But I doubt it is this simple, and this doesn't really explain how different instruments can play the same note but still sound different from each other.
The same problem also applies to computer image and audio files. Creating an image file from scratch is very simple, and understanding how the image data is stored also seems simple enough (if you exclude compression). Each pixel stores 8-bit values for red, green and blue (and I think transparency as well), and that's pretty much it.
But on the other hand I have no idea how audio information is stored in a computer. I also have no idea if it's possible to just created a sound from scratch. I don't think you can do it in the same way as you can open Paint and just scribble around.
It would be great if someone could explain this stuff to me. Thanks! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1uyn5v/eli5_what_sound_properties_do_different_musical/ | {
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"This has a lot to do with overtones and resonance. \n\nResonance is pretty self-explanatory: how well something (in the case an instrument) resonates throughout a room or building due to the sound waves bouncing and amplifying for a short period of time. \n\nOvertones are what make a sound \"thick.\" When an instrument plays a note, there is a dominant pitch that registers. However, there is also normally other pitches that \"surround\" that pitch to make it sound fuller. Think of a male falsetto note, or Pavarotti hitting that same note. One is thin without many overtones, and one is huge and thick.\n\nIf you play a note around a middle C on a piano and on a trumpet and a well-trained tenor sings the same note, none of these three things will sound the same as you have mentioned. This is because the piano has a fairly thin sound (less overtones), the trumpet uses its brass make-up to increase resonance and overtones, and a tenor would use his entire chest and nasal cavity to resonate the sound a fill an opera house. This applies for all musical instruments with some louder, thinner-sounding, thicker-sounding, irritating, warm and colorful etc..\n\nThis isn't a conclusive answer to your question but it is a little knowledge that I know and I hope it's helpful."
]
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] |
|
1rdpsh | does heat affect the energy absorbed by a solar panel? | I've been trying to better understand solar panels for a science fair project and my project is based around temperatures affect on them. I've received conflicting answers in my research and couldn't find a similar thread in ELI5. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1rdpsh/eli5_does_heat_affect_the_energy_absorbed_by_a/ | {
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"[Wiki section](_URL_0_)\n\nSo your run of the mill solar panel works because the electrons in the silicon are separated into two layers. There is a bottom layer of electrons with the silicon itself (the valence band), a layer of no electrons (band gap) and a top layer of electrons that move around (conduction band). A photovoltaic cell works be having a photon (light particle) come in and give its energy to an electron in the lower layer so that it can jump from the inner layer over the layer of nothing and into the top layer where the electron can move around and essentially create a current. [This is also why silicon is called a semi conductor, because it conducts in some situation and insulates in others]. \n\nNow, that band gap (the layer of nothing) is partially dependent on temperature. Temperature is sort of like the average energy of all the electrons, the majority of which are in the lower valence band. A higher temperature means that they will have a bit more energy and the band gap will be smaller, so you'll get more current out of your cell which is good.\n\n Bandgap has its fingers in many pies though, and changing the temperature is changing the bandgap. Changing the bandgap will change the highest possible voltage that the circuit can have. Higher temperatures end up having lower maximum voltages\n\n[This graph](_URL_1_) pretty much explains what happens with temperature. Higher temperatures mean higher current and lower maximum voltage. The voltage rapidly decreases though, so you can think of it as either on or off, and so you'd generally want higher temperatures. At any rate, the effect is fairly marginal. \n\nedit:I wrote this on the fly so I can reword things if it is confusing. ",
"I don't have the knowledge of semiconductor physics to explain why solar panels work less well when they're hot. Most things, as they get hot, act as if they have a higher resistance to the flow of electricity. But why is that? One explanation I see is that hot atoms jump around more than cold ones (that's the definition of \"hot\" on an atomic level), so the electrons have a harder time flowing around the atoms. See _URL_0_\n\nAnyway, regardless of the actual reason, I see no conflict in the answers that I have googled. When I googled this, every single answer said: \"solar panels deliver less power when they are hotter\".\n\nHere's an explanation that claims to explain why. I don't claim that I understand it in detail: _URL_1_\n\nHere's someone actually doing the test and their resulting data (just one of many that I found): _URL_2_"
]
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46ywe0 | why do most countries use the same calendar? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/46ywe0/eli5_why_do_most_countries_use_the_same_calendar/ | {
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"Europe and North America, which use a calendar based on the Christian calendar, export a lot of goods around the world. Other countries use the calendar because their major western trading partners do. ",
"Most countries in Europe came to use the Julian calendar (developed by the Romans), with some revisions endorsed by the Catholic Church, which we call the Gregorian calendar. The power of European colonization, trade, missionary work and military might spread it across the globe, and the last holdouts eventually bowed in the face of the benefits of standardization. Some do maintain parallel calendars to the Gregorian calendar, though.",
"Colonization.\n\nThe world was conquered by a few super powers and they implemented their culture, including calendars and timekeeping, wherever they went. Besides, travel and trade are easier when everyone is tracking time the same way. So, some places still respect their cultural calendars (like the Chinese and Hebrew calendars) while officially operating with the same calendar as the rest of the world.",
"It makes it way easier to organise dates. Thus making it easier to trade with different people on the planet or establish global relationships. \n\nIf there would be another calendar in place in France for example, I would be slightly discouraged trying to establish a private or professional relationship there. \n\nSame goes for the time.\n\n**TL;DR** It just makes things easier on a global scale",
"Why didn't a standard measurement system take off? ",
"As explained below, a lot of standardisation comes from not only Exploration Era European powers spreading the Gregorian calender, making other nations at the time use it for trade benefits. \n\nHowever some countries still adhere to their own standards. \n\nFor example- the one I know of is Japan, where while in international business they'll use the A.D. time scale, but in every day life, they use the number of years since their latest emperor was coronated (IIRC) . \nSo currently it's the 26th year of Akihito's reign as Emperor, which over there is known as the Heisei (㍻) Period. So in most governmental and every day things the date is written as ㍻26年2月22日 or The Heisei Era's 26th year, 2nd Month, 22nd Day.",
"Trade. Wars are fun to learn about, but economics shaped history. \n\nBut just so you know, there have been attempts. The French went so far as to euro-fy time. Down to ten hours in a day and even 100 \"decimal minutes\" in an hour. \n\nMy favorite is kodaks calendar. They used it for the internal business structure as late as the 90's, but it was also proposed as an international replacement. Kodak used it so long mainly because it made bookkeeping and accounting much easier because it you didn't have to worry about months with varying numbers of days. Plus it had the convenient effect of putting every date, every month, every year on the same day. The third of the month is *always* a Tuesday. The 20? Always a Friday (and yes the 13th too). The original proposal also moved holidays to where they were always on Monday. \n\nFor those wondering, the extra month was called Sol and it was in the summer (obviously). And for those of you who did the math, we got a December 29th. A holiday called year day. "
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fabqp7 | what does 'dry' mean in alcohol | I've never understood what dry gin (Gordon's), dry vermouth, or extra dry beer (Toohey's) etc means..
Seems very counter-intuitive to me. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fabqp7/eli5_what_does_dry_mean_in_alcohol/ | {
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"Imagine you worked at an ice cream shop.\n\nYou have 3 main types of ice cream.\n'Lip-smacking' sweet, 'Lemony-fruity' sorbet, and 'Cool-down' mint. \n\nIt can get a little tricky to explain minty flavours to customers, as there's a fine line for what some people may identify as 'cold' (which all ice cream is) and the cooling flavour of say, 'peppermint'. To communicate a little more effectively on the difference, it may be easier to have a different flavour identifier, in this case maybe...'cold-spicy'?\n\nThe term 'dry' in the drinks industry is similar to this in the sense that, in many cases, 'dry' simply refers to the more pronounced evidence of 'alcohol' flavour. The most well-known example of this is when ordering a 'Martini' cocktail. Asking for a dryer Martini just communicates that you like a higher ratio of alcohol vs the other additives (water & vermouth). Similarly, with white wine, a dryer tasting wine usually is an indication of the lesser amount of sugar levels of the wine prior to bottling. As all alcoholic beverages contain ethyl alcohol, the term 'dry' helps define the more clear & crisp flavour in certain 'boozy' flavoured drinks. \n\nThis is a very simplistic explanation, and misses out a lot of detail in the realm of sensory profiling in the biz, but it's a base understanding of how the term is used. \n\nSource: bar guy",
"In a very simplified way it refers to how sweet or, in this case, not sweet a drink is. A dry drink is not going to have much sugary (or fruity - another term used) taste in the mouth. \n\nSo a fruity drink is sweet while a dry drink is not sweet to the taste.",
"dry is the term used to describe the sensation of alcohol evaporating off of your tongue. It's generally the opposite of sweet.",
"Fully dry (“brut”) means the yeast have converted all available sugar to alcohol, leaving little/no residual sugar. A brut beer still has some residual sugar, and this is because yeast can’t eat maltose (malt sugar). In contrast, the sugar in fruit alcohol (cider, wine, champagne, etc) is fully digestible to the yeast, so a brut wine will have no residual sugar.\n\n*EDIT - other redditors have made right what I got wrong in the comments below. Here's a fresh take at the point I was attempting to make: It is a challenge to produce a fully dry maltose-based alcohol (e.g. beer) because the yeast will naturally cease activity before all sugar is consumed. Conversely, it is a challenge to produce a sweet or semi-sweet fructose-based alcohol (e.g. cider) because the yeast will generally be active until all sugar is consumed.",
"As the other commenter said, it's essentially the opposite of sweet. Dryness refers to how much of the sugar has been converted to alcohol. The drier it is, the less sugar left after the fermentation.",
"A few people have touched on a few accurate points here but dry can have several meanings, when it's in regards to a white wine or a rose it is generally a reduced sweetness due to the variety of grape and when it is harvested, with a red wine it is generally the tannin content that has the drying effect in your mouth,\n\nA dry gin can be two things, a London dry gin, which is a classification of gin not necessarily due to the sweetness, it's related to the distilling and steeping process involved in creating gin, whereas a non London dry gin that is dry is related to sweetness and mouth feel.\n\nDry cocktails are a combination of sweetness tasting, potentially tannin content, and acidity, but is a combination\n\nIt's a bit more complicated than this but this is the general outline for your average consumer\n\nSource; bartender for 3 and a bit years at nice venues",
"It very much is the opposite of sweet. But one thing I also like to mention is that it is so the opposite of sweet it feels dry. Its taken me a long time to like dry wine because it feels counterintuitive on the tongue. This liquid makes your mouth quite literally feel dry thats how unsweet it is. It certainly isn't bad and once your used to it is pretty good actually but its different for sure.",
"Wow, this was a rabbit hole - but I did some research.\n\nFirst, the meaning is pretty easy (and covered) - dry alcohol means not sweet. (London Dry Gin is a different story I'm not going into). So, if you see a wine or beer or alcohol listed as dry, there is usually a sweeter counterpart.\n\nBut, why \"dry\" to describe \"not sweet.\" The best answer I've been able to find is that we can trace the term centuries back - to the extent you need to look at french text from the 1200s for the first recorded references to \"vin sec\" (dry wine). When terms are that old, you usually loose the etymology - so all that is left is our best guesses.\n\nOne very good thought is that wine used to not be aged the way it is now. We lost the art of tightly sealing jars (perfected by Greeks and Romans) in the dark ages, so if you let wine age too long it would go bad. Aging is one way we can breakdown the chemicals that make a wine astringent. If you drink a very astringent wine, you will notice your mouth feels dry. Sweet wines (wines with more sugars in them) mask the astringency and would not have a dry mouth feel. As different ways of making wines and alcohols evolved in the ensuing centuries, we were able to make not-sweet alcohols that don't have this effect, but the term \"dry\" stuck.\n\nFor more extensive reading with lots of links: [_URL_0_](_URL_0_)",
"Yo! After panning through the replies, I figured I'd drop some thoughts here. Source: I am a Certified (edit: now Advanced!) Sommelier and a Certified Specialist of Spirits.\n\n**Dry, as some have mentioned, is the word used to describe the opposite of sweet.** I will reference a few laws below that use this definition in legal practice to confirm this as the internationally accepted, and in many cases, legally-binding definition.\n\nWater is dry. Add sugar to it and it has some level of sweetness. You might hear words like \"off-dry\" to describe a small amount of sugar, \"semi-sweet\" a bit sweeter yet, and \"sweet\" or \"lusciously sweet\" to describe things even sweeter still. These are typically used to describe ranges of sugar expressed in **grams of sugar per liter**, which, if you multiply by bald eagles and divide by original colonies, can be converted to American. ;)\n\nFor reference, Coca-Cola has \\~126g/L of sugar. It's what most industry folk would call something like \"sweet\", \"cloyingly sweet\", or \"lusciously sweet\". [Source.](_URL_1_)\n\nThe amount of sugar in a wine can typically be found (except by many American producers) by searching google for \"(insert wine name here) tech sheet\". For example, find the technical notes for Moët & Chandon Imperial Brut [here](_URL_0_), where sugar is listed under \"dosage\" to be 9g/L. Keep in mind that most bottles encountered in the wild are 750mL, so to obtain a sugar level per bottle, simply multiply by .75.\n\nA few laws for describing dryness, for the purpose of confirming the above definition:\n\nGerman wines are allowed to call their wines \"trocken\" (dry in German) if and only if the wine has 9g/L of sugar or fewer.\n\nVouvray, a wine-making village along France's Loire River Valley, only allows for their wines to be labeled \"sec\" (dry in French) if the wines have 8g/L of sugar or fewer.\n\nSee below for a law on Gin.\n\n & #x200B;\n\n**Common misconceptions:** \"Dry\" is often used by consumers to refer to the drying sensation one experiences after taking a sip of a beverage. This is a mistake, because the technical word to describe that sensation is \"bitterness”, while the word most often used to describe the bitterness coming from grape and oak tannins is “tannic”. However, most beverage professionals (assuming they're paying attention) are in tune with the fact that this misconception is quite prevalent, so an astute salesperson should respond to \"I'd like a dry wine\" with something to the effect of \"Dry as in 'the absence of sugar' or dry as in 'dries my mouth out'?\"\n\nThe word \"tannic\" describes the sensation of astringency brought on by tannin, a compound--long name polyphenols--found in grape skins. Red wine, which is colored by leaving the crushed grape skins in the juice until the color seeps out--think of a tea bag leaching out its color--are prone to having tannin by the nature of this process. The longer the skins stay in the juice (sometimes as long as several weeks) to color, flavor, and add texture to the wine, the more tannin will be extracted from the skins, and the more the wine will dry your mouth out. But, again, this is not \"dryness\" technically, this is tannin--polyphenols--binding to your saliva and leaving a drying, sandpaper-like, cottonmouth feeling. Tannin can also be found in such things as tea leaves. Think over-steeped tea.\n\n & #x200B;\n\nAbout things like gin specifically, London Dry Gin is a spirit which must, by law, be flavored predominantly by juniper and have no more than .1g/L of sugar. This level of sugar is what the industry folk would call \"bone dry\". Keep in mind that this is different from \"Dry Gin\" and simply \"Gin\", which are principally made the same way (by flavoring a neutral spirit) but may have different interpretations of flavors and different levels of alcohol and sweetness.\n\n & #x200B;\n\nDryness is also distinct from alcohol content in terms of organoleptic qualities, though high levels of alcohol can change the mouthfeel (especially adding viscosity, a liquid's resistance to flow or \"thickness\") and add a perceived sweetness--a bone dry liquid with the viscosity of maple syrup may seem sweeter to the taster than a bone dry liquid with the viscosity of skim milk simply by perception, even though the two liquids in question have the same amount of sugar.\n\n & #x200B;\n\n**A word of caution:** As alluded to above, many wines and spirits are regulated by law in their production. Those which are not so regulated (American products, and products of countries who don't have bi-lateral trade agreements with countries who do regulate these things) are a great deal more laissez-faire when it comes to what words and designations end up on their products. A wine labeled \"dry\" in the states has no required limit of sugar. It could have 200g/L and face no legal recourse for naming it as such. Do your research on wines if you have any questions!!\n\n & #x200B;\n\nHope this is helpful! Happy Thursday!",
"I’m a home brewer who occasionally also makes mead and wine so here’s my crack at it:\n\nAll booze starts off as super sweet sugary liquid. Yeast eats most sugars and poops alcohol. The more sugar that has been converted to alcohol, the “drier” the drink.",
"As everyone said, dry = not sweet. \n\nWith vermouth, dry vermouth is a whole different product than sweet vermouth. Sweet vermouth is normally dark, and dry is normally a white vermouth.\n\nOr, if you’re talking martini, dry means less vermouth. In this sense you’re thinking of “dry” vs “wet.”\n\nSource: bartender",
"Lots of talk about wine but I havent seen how it applies to beer mentioned so Ill take a stab at it. \n\nYeast eats sugar and makes alcohol. Malted barley (pre-beer) is sugar. Sometimes the yeast cant eat all the sugar and some is left. This leads to 'residual sweetness'. Think Russian imperial stout maybe?Sometimes the yeast eats all the sugar available and leaves a 'dry' beer like in a brut IPA. Sometimes a non-fermentable sugar (lactose) is added like in a milk stout. This also leaves a sweeter taste. \n\nOriginal gravity (O.G) Vs Final gravity (F.G.) is a helpful way to see this. O.G. is a measure of the sugar in a wort (pre-beer) available. F.G. is a measure of the amount of sugar when fermentation is finished. The higher the F.G. the sweeter the beer, the lower, the more alcohol and dryer the beer. Roughly.",
"In terms of actual chemistry, dry ethanol is ethanol with very little water. As both molecules are polar, they mix very readily. Removing water from ethanol can be done via distillation, followed by adding Magnesium Sulfate. It may be needed to dry ethanol if left open for a while when you need a pure ethanol solvent. This is not the same term as 'dry' when referring to an alcoholic beverage however - I believe in that context it refers to the flavour of the beverage.",
"If you are wondering \\*why\\* unsweet alcohol is characterized as \"dry,\" it actually goes all the way back to Hippocrates. He observed that people who drink too much wine could become dehydrated, and he also noted that the consumption of alcohol often brought a feeling of warmth, so he thought of wine as being both dry and hot, relative to other liquids. The \"heat\" of wine had nothing to do with its temperature (just like its \"dryness\" was unrelated to its liquid state), but rather with some sort of internal quality that is evidenced by what happens when you drink it.\n\nNoting that the sweetness of a wine inversely correlates with its suppressive effect on salivation, acrid wines were described as more ‘dry’ than sweet wines. \n\nFor ultimately similar reasons, we can refer to certain kinds of comedy as \"dry\" -- deadpan delivery lacks the outward signs of cheer associated with blood, which he thought of as particularly wet -- or as \"dark\" (associated with \"black bile,\" melan choler, from which we get the word melancholy).",
"Dry just means not sweet, as in the lack of sweetness. Something that is dry usually either contains less sugar or has some ingredients or flavors that hide the sweetness.\n\nThat is why the 2 varieties of vermouth are sweet and dry or sweet and not sweet.",
"Dry means no residual sugar.\n\nAlcohol is made by yeast consuming sugars and producing alcohol plus carbon dioxide. A “dry” product is one where the yeasts were allowed to consume all sugar. Semi-dry, semi-sweet or sweet are the other options, all based on the remaining sugar content. Yeasts will continue to consume sugars as long as they exist so to make a semi sweet product for example you have to either kill the yeast (arrested fermentation) or allow it to ferment to dry then remove the yeasts and then back sweeten with sugar or fruit juices.\n\n(I work at a cidery)",
" Dry as in the opposite of sweet. Less sweet, and more of the other flavors. The sweet can only be less, there is no actual literal opposite to it, it's just that the other flavors counterbalance the sweet.\n\n & #x200B;\n\nThe most obvious opposite of sweet is sour\n\n & #x200B;\n\nBut there is also astringency. That pucker the back of your tongue taste. Sumac has this taste, for comparison.\n\nSome bitterness also often comes along with the astringency, and is also part of the \"opposite\" of sweet\n\nAn astringent is something that constricts tissues. Witch Hazel, which you can buy OTC at any pharmacy, is an astringent. There are things in certain fruit juices and I think botanicals that are astringent that you taste. Since it constricts the tissues on your tongue, it literally feels like it's trying to dry out your tongue.",
"Bartender here, just wanted to add a few things to the glorious comment from our resident som and spirits expert. \n\n\nAs far as London dry gin goes, that’s the title of one of five different types of gin. London dry is the most regulated and has very specific parameters it must conform to in order to be labeled as London dry. The other gin types are old Tom, genever, contemporary, and plymouth. You can think of these in terms of whiskey if that helps. For example, both bourbon and scotch are whiskeys, but they have very different requirements to be labeled as such. \n\n\nSimilarly, dry vermouth is a type of vermouth, or fortified wine. There are other types of fortified wine which may or may not be called vermouth, such as cocchi americano or blanc vermouth. The other most popular vermouth is sweet vermouth, which gets its name from the burnt sugar present in most sweet vermouths. You’ll find dry vermouth, the straw colored stuff, in a martini, and you’ll find sweet vermouth, the brown stuff, in a Manhattan. \n\n\nCheers!\n\n\nEdit: it’s also very popular to order a “dry” martini. In that context, what the guest usually means is that they want a martini made with less dry vermouth. It’s frustrating and extremely counter intuitive, but that’s the typical nomenclature used by the average consumer.",
"I believe it has to do with having less or no residual sugars or the lack of the ability of the palate to detect them. Sugar tend to round the mouth feel of a drink make it \"softer\" on the palate.\n\n non expert but I took a wine class in school so take this with a grain of salt.."
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3xsy3o | when igniting a flammable substance from a gas canister, why doesn't the flame travel inwards towards the source and blow up the gas canister | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3xsy3o/eli5_when_igniting_a_flammable_substance_from_a/ | {
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"you need oxygen/fuel at a minimum ratio to combust. There is little or no oxygen in the gas canister.",
"Because the gas canister is pushing the gas out and away, there is also no oxygen inside the canister, which prevents the gas inside from catching fire.\n\nIf you put a gas canister (with the valve shut) into a fire, two things could happen:\n\n* Some canisters (especially in laboratories) have security valves that open when there's too much pressure, the heat makes the gas inside expand, so the valve opens and releases the gas, it catches fire.\n* The gas inside keeps expanding untill the entire canister explodes, this is by far the worst alternative.",
"For some gases and liquids that CAN happen. Like ethylene oxide or nitro methane as examples. In fact they have to use detonation traps.\n\nOn nitro methane:\n_URL_0_\n\" The employer did not protect its employees from the recognized hazard of fire and explosion in that pipes, one-half inch or greater in diameter containing nitromethane and/or a nitroethane mixture, located in pipe racks in the nitroparaffin plant were not equipped with detonation traps.\"\n\nOn ethylene oxide:\n_URL_1_\n"
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76xnq6 | - are speed bumps designed to damage your car if you go over them too fast? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/76xnq6/eli5_are_speed_bumps_designed_to_damage_your_car/ | {
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"Some are, yes. We have the normal speed bumps but there is a whole road nearby that uses ~~his~~ these rubber things bolted down and even if you are going really slowly the jolt they give you is enormous. ",
"every time you drive your car, yes, the suspension will suffer wear & tear. If you hit bumps like they weren't there, you will just wear out the suspension a bit sooner.",
"If you hit them too fast, the suspension will pack down and you risk smacking the front plastics of the car into the ground. \n\nProperly shaped and sized speed bumps shouldn't do any damage as long as you slow down enough.\n\nMost speed bumps should be driven over at less than 20mph. ",
"Speed bumps are intended to force drivers to slow their speed. Most are designed in such a way to make it uncomfortable for the driver to take them too fast, but are not intended to damage their vehicle. Others are poorly designed and *will* damage the vehicle, even at a reasonable speed. Even properly designed speed bumps can damage a vehicle if the vehicle is going much too fast, though.\n\nThe wear and tear you experience going over a speed bump is negligible. You'll experience more wear and tear through simple road driving because you do more road driving than you spend time driving over speed bumps.\n\nThing to remember about speed bumps is this: the speed that it is safest to driver over the speed bump is the speed you are supposed to be driving on the road even where there are no speed bumps. If you are going 45 mph, then slow down to 25 mph to go over the speed bump, accelerate back up to 45, slow down to 25, again to go over the next speed bump, you are doing it wrong. You should be traveling 25 up to the speed bump, over the speed bump and between the speed bump. The city likely placed the speed bump on that road because drivers are travelling that road too fast.",
"Square edge bumps (rough roads, potholes) will wear your suspension out faster than speed bumps because these are felt as impacts that are transmitted to the bushings in your suspension. \n\nSpeed bumps are smooth, they are soaked up by the normal travel of suspension and are not jarring impacts. As long as you are not bottoming out your suspension by going over them too fast (felt as a clunk) they will not hurt your car. ",
"No, speed bumps are designed so that if *you* drive over them too fast, *you* will damage your car. ",
"Let me tell you a story;\n\nBack in college I got a ride with this guy from my class, cool guy but thick, there were 5 of us in the car and 2 Lads were goading him in to speeding.\n\nThen they saw a speed bump and one guy said “I bet you can’t get air off that speed bump”. This guy goes full pelt into a speed bump trying to get air, as soon as he hit the speed bump the front of his car disintegrated. It felt like I’d been smashed by a truck, the whole front end of his car was all jacked up and so were our bodies.\n\nSpeed bumps are designed to act more like a wall the faster you go, so yeah they are designed to destroy your car unless you take them slow.",
"When you hit a speed bump too fast, it causes the suspension to compress in a very short amount of time, which generates high peak forces in the suspension that can damage seals and bushings. It's all about the mass, the displacement (speed bump), and speed. Increasing any of those will increase the impulse. Increase the impulse too much, and stuff will break.",
"In portuguese, speed bumps are called \"quebra-molas\". roughly translated, it means \"suspension-breaker\". So yes, I think so."
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2ofah9 | the purpose of the recent orion flight and what it means for both future space exploration as well as nasa itself? | I have been very into the whole Orion launch, but then I saw the flight path which was just a single orbit around the planet; don't we have satellites that do that everyday? Did we not make this feat years ago? I must be missing something here, please enlighten me! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ofah9/eli5_the_purpose_of_the_recent_orion_flight_and/ | {
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"It was to first test out if the Orion was safe for human Flight. If something went wrong with the capsule, they could use the data to avoid astronauts being killed.\n\nAs far as the future is concerned, this can really mean anything. NASA is currently planning to use this series of vehicle to transport humans to mars, and to set up a colony there. For the expedition participants, it will be a one way trip.\n\nThe Orion is designed to be able to dynamically attach to a lot of different add ons, like a larger living area on long expeditions, using the same example as mars.\n\nIn the future, this may be used as what brings astronauts to iss, since its reusable and cheaper than space shuttle to maintain. The rockets designed to launch it with(not this test flights, this time they used delta IV heavy; the actual one is still in construction) will allow deep space exploration line never before due to its massive thrust.\n\nSo really, in short it means manned space exploration and colonization."
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b7xi4m | why dont oasis in deserts get filled by nearby sand over time | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b7xi4m/eli5_why_dont_oasis_in_deserts_get_filled_by/ | {
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"An Oasis gets its water from underground aquifers. So the water would just push any sand away. Also the presence of plant life around it helps keep the terrain stable, reducing the amount of stuff that'd disrupt things."
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3le4xg | what dictates a wonder of the world? | I'm a bit confused as to why there are only 14, 7 from ancient and modern world, and why they chose those 7 for each specifically. For the longest time I thought stonehenge was a wonder, but it wasn't, as well as the easter island heads, those things were full of 'wonder' as people couldn't figure them out. But they aren't put as wonders. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3le4xg/eli5_what_dictates_a_wonder_of_the_world/ | {
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"There is no particular standard, only tradition. The Greeks made lists of amazing things from around the Mediterranean world familiar to them. Most of these lists made 7 choices because the number was (and often still is) considered lucky; counting the sun and moon, they knew of seven planets.\n\nAntipater of Sidon made a particularly popular list which many other authors referred to, and which has survived into the present day as *the* list of the Wonders of the Ancient World. His choices were arbitrary based on what he knew.\n\nRecently, people have tried to make lists of modern wonders based on various criteria. (The idea being that they are only possible with modern technology.) There's no particular list that is commonly accepted as authoritative."
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73rsfz | inflation & deflation | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/73rsfz/eli5_inflation_deflation/ | {
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"Inflation & Deflation aren't about currency rate, they are about price level in a country. Despite the reason inflation makes some products more expensive, or you can buy lesser with money you have. You can't increase salaries at the same time because it will cause futher increasing of the prices (it is actually one of the reasons). The problem of inflation is in behavior of people and firms, when prices go up people can't afford to buy some things therefore firm can't get their profit and won't be able to pay loans or invest in futher production, then the amount of supply will decrease. When supply decreases usually prices increase so there is a cycle: goods are expensive, people buy less, lesser goods are produces, goods are more expensive. \nDeflation is bad as well. If you can buy a can of coke for a dollar today and two cans next year, you will be saving more money and again, companies won't be able to pay loans etc."
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8dfsez | how do snails not lose all of their body mass as slime left on the floor while travelling? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8dfsez/eli5_how_do_snails_not_lose_all_of_their_body/ | {
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"Imagine it like sweating. You can sweat and sweat, liquid comes out of you, but your body mass stays more or less the same.",
"They do lose some. But just like you can continue to make snot and saliva, pee and poop, they consume material to make more."
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1jew59 | why was there a theory that nothing can go faster then light? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1jew59/why_was_there_a_theory_that_nothing_can_go_faster/ | {
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"Your wording is odd. You ask \"why was there\" is if it's not a current theory. As far as we know, it still holds true. As to why, see the other commenter.",
"The relativity theory is very much valid.\n\nI can try to explain a bit, but it's probably better explained by minute physics.\n\nFirst watch this: \n_URL_2_\n\nand then watch this: \n_URL_1_\n\nIt's a great youtube channel in general, so if you're not bored yet, go here: \n_URL_0_",
"The theory of relativity relies on defining the speed of light in order to make the math work. The speed of light in a vacuum, c, is also the speed of physics (cause and effect). It's like the network latency between different parts of space.\n\nThe assumption that the speed of light is constant and that nothing can go faster that it makes the theory of relativity work. And relativity leads to some non-intuitive conclusions that can be tested experimentally. And those tests have all come back positive. And the theory of relativity at its core is simple and elegant; so it is likely that it is true.\n\nBy the way, if you're asking this question because you're thinking about faster-than-light travel, there are ways around that. Just think about how to travel without exceeding the speed of light through the space that you occupy. The Alcubierre Drive gets around this by stretching space ahead and behind you, so you're never breaking the speed of light even though you kind of are. Wormholes are another idea, where you travel along a shortcut that connects distant parts of space, but along that path you don't exceed the speed of light.",
"The idea is not that something's holding back particles from going beyond the speed of light, but rather, the idea is that its **logically impossible** for anything to go faster than light.\n\nThe speed-of-light is a fundamental constant of our universe. A large number of laws of physics are based on this constant. You can say its an \"innate property\" of our universe.\n\nSometime back, neutrinos were observed to go faster than light, and this was a shockwave to every physicist, because if it were true, then all our fundamental laws of physics would have to be re-worked. It was later found that this was due to an experimental error, and the neutrinos never traveled faster than light. This means our laws of physics were correct all along and all is well."
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90dv3t | why aren't news stations (local, national, international) required to cite sources? | All (or most, I skimmed) of these responses seem reasonable and logical. I know it would be difficult if not impossible to do so without imposing on freedom of speech, but it just seems there must be some way to be able to verify information and a simple, truthful, immutable way which cannot be manipulated or corrupted. I feel there is a technology waiting to be discovered.. maybe it's just hopeless optimism. But then again, innovations have been doing what was once thought impossible time and again, and since history is bound to repeat itself.. well. One can hope, for the sanity of humanity (rhyme intended)
Thanks for all the input! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/90dv3t/eli5_why_arent_news_stations_local_national/ | {
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"One reason that news reporters (be they text or video) are not required to cite sources is that doing so can result in the firing, the arrest, or even the execution of the people who are their sources. Journalists take protecting these sources very seriously. ",
"Because asking for sources and punishing s newspaper if they are absent is a pathway for censorship. Who defines if it's enough of a source? The government?",
"Who do you think has the power to make them do so?\n\n > Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.\n\nSo, in the US, at least, they can't (and shouldn't) be forced to.\n\nYou want to be careful that the medicine isn't worse than the disease. A free press is kind of a big deal in a free society.",
"You can't 'require' anything from the press, in the US. Freedom of the press means what it says on the tin.\n\nHalf the time, they're the ones doing primary journalism anyway when reporting on their relevant spheres, so they're their own source.",
"Aside from all of the wonderful explanations so far, I'd like to point out that if you contact a news station and ask for the specific sources that lead to a broadcast, they'll often email them to you at no cost. ",
"They often do, for example when they interview someone and use that information they say so, \"During our interview the president said...\" Other times, when they use other news outlets they say which outlet they got the info from, \"The Associated Press reports that...\" When official statements come out they often refer to a press release or corporate/government report. The source citations can fly by unnoticed if you're not actively listening for them. ",
"If you are talking in the usa it goes with the freedom of the press. A true journalist would protect their source but make a great effort to see if the source is telling the truth.",
"The constitution.\n\nFreedom of speech. Freedom of press. You can report any story you want and choose to divulge or not divulge sources. Because the government cannot dictate the content. Of course if your story isn't accurate and causes damage to someone you may be subject to civil action against you. Free speech is not without consequence.",
"Because the news station itself is the source. Their capture of the information through interview or video or both provides the informational content.\n\nThere are some cases where you will hear a newscaster say \"From our sister station at KXED in Des Moines.\" or \"NBC's National Correspondant Joe Blow\". That's their way of citing as well.\n\n"
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3wz3ja | how are sentences by judges that are aimed at making an example out guilty parties not a violation of "equal justice under law", and therefore unconstitutional? | Edit: out of* | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3wz3ja/eli5_how_are_sentences_by_judges_that_are_aimed/ | {
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"Each type of crime has a valid minimum and maximum sentence. As long as the judge stays within these guidelines, it is 100% legal."
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3nh72n | why don't tv shows/movies show real websites like google and facebook? why use fake websites that look like them? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3nh72n/eli5_why_dont_tv_showsmovies_show_real_websites/ | {
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"Because you gotta call them, ask for permission, sometimes they ask for a certain fee, have their PR people see if their product is being used in good faith, all that paperwork and time just isn't worth the trouble. You can literally have a mock up site with basic functions working in one or two days and pay the guy 200 bucks for it.\n\n"
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5lcm18 | why do old games running on new hardware still have technical issues? | I am playing some mega man games on my Xbox One and experience slowdown when there are a lot of enemies on screen. but the Xbox One is significantly more powerful than the NES, so why is there still slowdown on this hardware? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5lcm18/eli5_why_do_old_games_running_on_new_hardware/ | {
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"The XBox is emulating NES hardware and running the emulation at a set speed. If it ran it at as fast as possible, then it would be several times faster than the original NES game and would be unplayable. I can't speak for Mega Man exactly, but older games tended to run on a cycle locked to the screen refresh which was a fixed 60Hz or 50Hz. There was only one piece of hardware they ran on, so there was no need to adjust for different hardware speeds.",
"In that case, it's probably on purpose - they want to emulate the experience as closely as possible, even including the slowdown and sprite flickering. Some emulators let you turn it off, but it's usually turned on by default.\n\nIn other cases, like if you're trying to emulate PS2 games on your PC, the game might just run really slow in general. Even though your PC is way more powerful than a PS2, it has to \"translate\" from PS2 language to PC language in realtime, which is much more difficult than running PS2 code on the PS2 itself.",
"The emulator is designed to match the actual behavior of NES hardware under real conditions as closely as possible. It is actually very important that an emulator be designed to do this, otherwise it can cause problems. In rare cases, a game will be designed to work around or even make use of a specific hardware fault or issue, and will crash or fail to work entirely when the emulator doesn't replicate this. \n\nA good example of this is Speedy Gonzales on the SNES. Only Higan , which has cycle-accurate emulation, will successfully run the entire game. All other emulators will freeze at a very specific point. Another would be the YM2612 FM synthesis chip from the Genesis/Mega Drive. All current Genesis emulators only emulate the very similar but not identical YM3438, and earlier games that used the unique distortion present in the YM2612 will not have proper music emulation.",
"This sounds similar to a situation I experienced years ago with varying graphics computers in my art department. Back in 1990, my Mac computer was older than the newer more powerful Macs my staff had. Yet my computer which did not have the power of the others displayed faster than the newer computers because as we would discover my monitor port was faster. So even though the newer computers could process the math faster, they could not render it faster so the visual perception was slower. \n\nAs for having so many enemies on the screen, this sounds like a problem unrelated to the power difference. I still love to play Dune on my PlayStation II, and I love to reach the point where I have big battles with lots of tanks, men, quads, gun towers and buildings and the game will crawl. But I notice that the enemy action the computer generates isn't as slow to act as the commends sent by me via the controller. My men move slowly while the enemy moves faster. Thus there is a timing difference in processing between those commands sent via the controller port vs. those sent by the cpu. Both the cpu commands and the controller commands are sent equally to through the TV port. There is a time delay between what I see on the screen, my reaction and commands, processing those commands and sending the result to the monitor. The enemy does not have as long a time delay because there is no controller involved. When there is less action on the screen we probably don't notice the time difference, but when the action is heavy and the processing overwhelms the cpu external commands get second priority. "
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esbsy7 | when a court tries to discover whether someone is guilty or innocent, does their lawyer know the truth? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/esbsy7/eli5_when_a_court_tries_to_discover_whether/ | {
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"Sometimes they know sometimes they don't. \n\nAttorney client privledge is a common law understanding in the US that your lawyer cannot divulge or be forced to divulge what you've told them. \n\nThis way you are encouraged to tell them the truth so they may best come up with a plan for your defense. There are of course some accused who will not admit guilt to their attorneys. Realistically we would never know if attorney knew or not.",
"It's not guilty or innocent, it's guilty or non-guilty. You may think that it's not a small detail, but that's important. The court never know if the guy is innocent, they only know if there is enough good evidence to declare him guilty or not. The defender doesn't need to prove that he is innocent, only that he is not guilty.\n\nAs for the defender's lawyer, he could know or not know. It depend if the accused decided to tell his lawyer or not. The lawyer could also not know, but be pretty sure that his client did it. \n\nAnyway, at this point the lawyer only have 2 options. Either he decide to retract himself from the case, or he need to defend his client at the best of his capability.",
"All parties involved have access to all the evidence available. It's not like \"the truth\" suddenly manifests itself in the courtroom to the surprise of everyone present. Nor does it matter.\n\nThe defending lawyer isn't there to prove innocence. He's there to ensure that his client receives a fair trial, that the prosecution is doing their job, that the evidence brought forth is valid, and trying to cast reasonable doubt on every single statement brought to question in discovery. If that's impossible he still has the job of making sure that his client receives a fair treatment and sentencing even when guilty beyond doubt. \n\nHowever in most cases lying to your lawyer is a stupid move, because it hinders his ability to actually help you.",
"A lawyer is legally required to turn over all their evidence to their opponents before the court. The exception is his conversations with his client which are confidential. However statements in general is untrustworthy and there are plenty of cases where clients have admited their guilt to their attorney even though there are solid evidence they are innocent. So the lawyer generally does not know much more about the case then the rest of the court. However their job is not to hide the evidence but make sure their clients are getting the justice they deserve and are not getting punished too harshly. In a lot of cases there is no question of guilt but rather how hard the punishment should be. A lot of lawyers will even instruct their clients to not tell them more about the case then they already told police as that is unnecesary information to them. The lawyers job is to present the evidence to the court in a way which is most advantagious to their client. The question of guilt is not really part of the equation for them. That being said the lawyers have a lot of experience with liers and can often uncover their clients lies quite fast. So even if there is little evidence they can often make a pretty good guess about their clients guilt. But even criminals have the right to a proper representation in court and a fair punishment for their crimes.",
"In most cases the defendant's lawyer knows the truth.\n\nCourt is less about finding the truth, and more about proving something based on a given set of rules.\n\nWhich is why defense teams are not always as concerned about whether their client is innocent or guilty, it's based on the rules of evidence, can it be proven (beyond doubt).\n\nThere is no discovering of truth, the prosecution and defense share everything they have before hand.. it's aptly named discovery. So everything presented, both sides have had a chance to review (few exceptions apply) The only \"surprise\" is what a witness might say on the stand when cross examined. As in If one side calls a witness to the stand, the other side gets to ask questions. Normally the witness is prepared for the questions but maybe a curveball is thrown and the stress/question makes the witness answer in a way that was not predicted... Or a lawyer uses the emotions of the case (like anger, jealousy, etc) to get the witness to blurt something out.\n\nFinally, If there is a jury, then the judge is not there to decide if it's innocent or guilty, he is actually a referee designed to make sure both lawyers are following the rules. Since the jury (and most regular people) don't know all the rules of court and evidence. The judge will allow or not allow pieces of evidence, testimony, etc as a way to make sure all the rules are being followed.",
"They know what they've been told and been instructed to find out.\n\nBeyond that, it's as much hearsay as anyone else saying they \"know\" he did it.\n\nIt's also generally frowned upon to \\*admit guilt\\* to your lawyer and then expect them to plead your innocence. They will likely advise you not to say things like that, or to change your plea to guilty.\n\nThat would likely be via a roundabout \"I'm sorry, are you admitting guilt to me, thus putting me into a position where I couldn't ever represent to the court that you're innocent?\" kind of way that most people would take the hint and say \"Oh, no, I mis-spoke, I didn't do it, honest\" even though everyone involved knows exactly what's going on.\n\nA lawyer can't knowingly lie to the court. But given that attorney-client privileges means all such discussions are private even from the courts themselves, there's no (easy) way to prove that they are doing so. If, however, you said you were guilty and stabbed him with a knife you buried < here > and your lawyer then tries to act as if he weren't aware of that evidence when it comes up later, there is a massive legal problem. He can't just ignore that fact, necessarily.\n\nTip: Don't put your lawyer in that position. If you want them to prove your innocence, don't tell them you're guilty (and vice-versa!). They won't appreciate it.\n\nIf they think you're guilty, they're supposed to still represent your interests (e.g. a lenient sentence) but to do that they'll expect you to plead guilty.\n\nWhat they'll do is claim ignorance, even though they are more than smart enough to know what's going on, and advise you to plead guilty if you say you are. Anyone with half a brain will follow what they advise, which will basically be to never suggest you're actually guilty to anyone, including themselves."
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8yiwo3 | is a fat muffin top at your belly caused because humans wear clothes around their waistline? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8yiwo3/eli5_is_a_fat_muffin_top_at_your_belly_caused/ | {
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"Really good question! I am by no means an expert but it is my understanding that every person stores fat on their bod differently, however fat naturally collects around the waistline, modern clothes or not. Wearing tight jeans or yoga pants accentuates the “over hang” or “muffin top” on some people.",
"Yes, but not by much. Your fat stores are all located in/around your hips/pelvic region, they swell and become distended due to an increase in volume of fat storage. Squeezing into tighter clothing does cause certain shapes (i.e. muffin top) to form, but it has no impact on the overall volume. \n\nSo if you are carrying weight in your belly it's not like that weight is going to suddenly shift to your thights, it'll still be there but just in a different shape. "
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2faazm | our defense system in the united states if nuclear missiles were to be launched at us by another country | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2faazm/eli5_our_defense_system_in_the_united_states_if/ | {
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"Honestly? Not super great.\n\nWe have some [missile intercept systems](_URL_0_) but mostly the US relies on its ability to say \"If you don't terminate your missile right now... we'll fucking destroy your entire country in one swing\".",
"Mutually Assured Destruction (MAD)\n\nThe US maintains a triad nuclear defense system meaning it can strike via land, air, and sea. You can not stop it from attacking if it has made the decision to launch. In the event of a nuclear attack on the US, or one of its NATO allies, the US will unleash it's nuclear armada on the aggressor, theoretically destroying them outright. \n\nThe US has experimented with missile interception systems but that have never had success rates that would offer any real defense against a major attack. ",
"Nice try Putin ;)"
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3wewk9 | why do storm troopers wear armor if it doesn't actually protect them from anything? it also apparently interferes with their ability to shoot accurately. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3wewk9/eli5_why_do_storm_troopers_wear_armor_if_it/ | {
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"Psychological edge. A phalanx of faceless, white-clad, cold, armored soldiers advancing will make you shit yourself. It's a powerful image.",
"There are several theories as to their accuracy, they appear to be accurate all the time except for a few instances where vader lets his son and a small group of rebels escape on a few occasions to track them to various rebel bases. The armor, kind of like actual body armor, is no guarantee you wont get killed. Weapons are easier to make effective than armor because generally speaking its easier to wreck stuff that to build stuff. The armor is good against shrapnel, hits to extremeties, and might even keep you alive from an otherwise fatal shot, but a shot to the chest or head is always going to be potentially deadly even with the best armours money can buy (think boba fett) but these guys arent intergalactic bounty hunters, they are rank and file troopers, so they definitely are NOT getting the best stuff on the market, they are getting something that can be made as cheap as possible.",
"You should check out /r/asksciencefiction they'll give you a much more detailed answer.\n\nShort version is - much like body armor today, Storm Trooper armor is amazing at stopping non-military grade weapons. Someone in the full kit is basically immune to slug throwers (re: normal guns) unless they take a very unlucky hit to a joint/eye socket or if the round is specifically armor piercing or very large.\n\nBlasters are military grade tech and (naturally) can over match the armor. That being said, the armor has a great deal of ablative power and can often minimize the damage to the core body from a blaster. It'll hurt like hell and multiple hits are still likely to be lethal... but you have a better chance than you would unarmored."
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abs03p | how did we find out that there are 365.25 days in a year? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/abs03p/eli5_how_did_we_find_out_that_there_are_36525/ | {
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"Observation, and knowing when the sun should be where through relative position.\n\nWhen you chart the sun’s course every day of the year a pattern emerges (Note the position and degree of the light at the exact same time every day). That pattern is slightly off by a few degrees the following year, on a four your cyclical. This ellipsis is the foundation of time as we know it. ",
"With a [sundial](_URL_0_)\n\nA sundial tells you the time of day with the shadow of a stick: Noon is the point where the shadow casts the shortest shadow because it's highest in the sky at that time. It's also the easiest way to tell the cardinal directions without a compass, since the shadow is going to point exactly north at noon.\n\nNow if you start recording the distance between the stick and the shadow at noon each day of the year, you're going to figure out the dates of the summer solstice (where the sun is the highest in the year) and the winter solstice (where it is the lowest). The number of days between either of the solstices is the time it takes for the earth to revolve around the sun, and this will tell you that the year is 365 days long, a quarter day short of the more precise 365.25 days.\n\nHowever, after four years, the difference will add up to a full day, and the solstice will be recorded one day later than expected. This might have flown under the radar for a while since nailing the solstice to a day with nothing but a sundial is hard, but at some point they must have noticed that their calendar was wrong and corrected it. The Romans divided the difference between recorded and actual solstice by the number of years that passed, and got to 1/4 of a day per year.\n\nOther cultures came to different solutions to the problem, for example the Chinese lunar calendar occasionally jumps an entire month. I'm not quite sure how it works exactly though.\n\n\n"
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49howb | 3 days underwater. | I saw an old post about a rather old story involving a Cook from a ship that survived 3 days underwater. the ship was "AHT Jascon 4," the man was named Harrison Odjegba Okene. Given the limited space, confined area, and amount of time how did he not run out of breathable air or die of C02 poisoning. " inert gas asphyxiation " | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/49howb/eli5_3_days_underwater/ | {
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"In short, they haven't come up with a good answer yet.\n\nThe key problem more than anything is hypothermia. He was trapped in freezing water, and found naked and alert. After three days in freezing water you'd expect someone to have drowned, let alone be naked and able to determine that someone was rescuing them.\n\nThe other problem is oxygen. While bubbles can trap oxygen under water, the oxygen will eventually dissipate into the water around it and be replaced with Nitrogen. Diving Bell spiders have been able to keep oxygen bubbles going for 37 at most. 72 hours has never been observed before, and this is from an insect that uses a tiny fraction of the oxygen of a human and wasn't experiencing hypothermia, which in respiratory terms is as intense as a heavy workout for how much oxygen you use.",
"The belief is that the air pocket was big enough and in combination with the pressurization of the air provided him enough oxygen, which was a very close thing he was almost out when found. The carbon dioxide was supposedly absorbed into the water at a rate that kept it from being deadly, he apparently splashed the water increasing its surface area and thereby increasing the absorption of carbon dioxide. He escaped hypothermia by making some type of platform which allowed him to not spend the entire 60 hours in the water. \n\n_URL_0_"
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1jln5o | why does fruit taste different after its dried? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1jln5o/eli5_why_does_fruit_taste_different_after_its/ | {
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"the flavor is concentrated since there is less water, it would be like making a cup of coffee with just a little bit of water so you had a thick mud... it would taste different."
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d3ivv2 | exactly how are manual eye exams conducted (without modern digital equipment) and how can a doctor measure your eyesight through looking at your eye? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/d3ivv2/eli5_exactly_how_are_manual_eye_exams_conducted/ | {
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"What do you mean measure your eyesight? As in determine your visual acuity?",
"Before the fancy digital eye scanner... They had you look through lens and ask if it was better or worse...."
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3x0k6h | when and why did we switch from saying liberal/conservative to progressive/regressive in us politics? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3x0k6h/eli5_when_and_why_did_we_switch_from_saying/ | {
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"Political terms change over time, and often have many different meanings.\n\nHistorically, a \"liberal\" was someone who believed strongly in republicanism and democracy. The \"conservatives\" in England opposed the revolutionary change seen in France, seeing it as dangerous, and wanted to preserve the existing social order with moderate reforms.\n\n\"Progressives\" came later in the 19th century, and wanted wealth re-distribution and more social spending. It's really a better term for most Democrats than \"liberal,\" since the use of that term is not that applicable in American politics. On the other hand, \"conservative\" does match most Republicans.",
"Progressive is a nonsense word when it comes to politics. Is it progressive to support gay marriage? To expand government for social welfare programs? To prematurely strike disagreeable nations? Subjectively anything may be, but it may be regressive to others. ",
"A lot of politics comes down to terminology. Communists were difficult to argue with because they came up with they own bourgeois/proletariat jargon, giving them a home field advantage in any discussion.\n\nIn the 1980s, Republicans were successful in making liberal into a bad word, making Democrats shy away from it and becoming more moderate. Much of the sentiment remains, so liberal Democrats have reinvented them themselves as progressives.\n\nAs for the use of regressive, that is just childish name calling and word games. It is no different than pro-lifers calling their opponents pro-death. If you can't address your opponents with neutral terms or the terms they choose for themselves, you lack the maturity to carry on serious political discussion."
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2fjpa2 | sunk costs | Could it be explained with an example as well? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2fjpa2/eli5sunk_costs/ | {
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"A sunk cost is a past cost that is not recoverable and specifically should not influence future decisions. For example if a company spends money on a consultant then that money would be sunk. Also money spent on employee training is a sunk cost. In contrast to money spent on a truck or a computer of which some money would be recoverable. ",
"Imagine that you are starting a business. Some of the costs you will experience may be:\n\nA) Pay a consultant to help you set up your business\n\nB) Rent a building to work out of\n\nC) Pay for electricity to run your machines\n\nD) Buy 1000 business cards\n\nJust about all costs can be put into 1 of 3 categories: (1) Fixed, (2) Variable, (3) Sunk. We categorize them to help us streamline processes, keep track of money and margins, and help make our companies stronger and financially healthy.\n\nA **Fixed** cost is just like it sounds. It is \"fixed\". The rent you pay on your building, for example, is likely the same amount each and every month. Let's say your rent is $1,000 per month. This means that I can correctly predict that after 1 year, it will cost me $12,000 (12 * $1,000) to rent my building. After 2 years, it should be about $24,000. A fixed cost will be nearly the same across a defined period of time with little to no change.\n\nA **Variable** cost, similarly, is what it sounds like, too. It varies. Your electricity bill, for example, will be higher when you use more electricity and lower when you use less. If, for example, your electricity bill is $1,000 one month to run your equipment, it may be $2,000 the next month if you double the amount of work/output. Likewise, if your electricity bill is pretty constantly $1,000, there is an **opportunity** to possibly reduce it by investing in more efficient machines which may then reduce the amount of electricity used (and then lower your bill). Overall, though, they fluctuate depending on the amount of work being done. This is *unlike* **fixed** costs, because your rent of $1,000 per month will be $1,000 regardless of how much work you do in your building. \n\nA **Sunk** cost is an expense that you no longer have control over. You have to just accept it. Let's say, for example, you pre-pay rent for a whole year and your contract prevents you from subleasing/renting it out to others. Suddenly, you find a better location and move. The $12,000 you paid in rent for your old building is a \"sunk cost\" because there is nothing you can do to recover it or a portion of it. Likewise, the 1000 business cards you ordered with the old address are a sunk cost, as there is nothing you can do to recover the money you spent on them. The consultant you already paid to help you is also a sunk cost.\n\nLet's say that you plan on reselling someone else's products through your company. You sign a contract with ACME Corp to provide you with 1,000 widgets at a cost of $1 per widget that you plan on selling for $2 per widget. It takes time for those 1,000 widgets to be made, but you form the agreement now.\n\nSuddenly, something happens in the market. No one really wants widgets anymore. In fact, the best you can do is sell them for $0.50 each when you end up getting them. So you've paid an expense of $1,000 expecting to make a profit of $1,000, but now you will make no more than $500 total, which means you paid $1,000 to lose $500. That $500 is a sunk cost. ",
"Just to add a simple example, let's say you paid $100 dollars for a concert ticket, Then, on the day of the concert, you decided that you no longer wanted to go, and you find that other people will only buy the same ticket from you for $60. Then the $40 dollars that you can't get back constitute the sunk cost.\n\nOoh, and here's a neat thought: almost all people find themselves subject to sunk cost fallacy, where they believe that making economically inefficient choices will somehow allow them to recoup sunk costs. For the above example, that would be the same as thinking to oneself, \"I don't want to go to the concert, but I have to or I lose those forty dollars,\" when the forty dollars have already been lost, and the real trade-off is between $60 and the opportunity to attend the concert."
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5kx7l3 | why do some people silently mouth the words you're speaking along with you as you talk to them? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5kx7l3/eli5_why_do_some_people_silently_mouth_the_words/ | {
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"Probably improves understanding. At least you know they're paying attention to what you're saying.\n\nSome people have a hard time focusing, their minds wander.",
"Its a form of face mirroring. As social creatures people will mirror face expressions, to \"fit in\" with the social group. This is why people often will have the same face expressions as someone they are listening to them. Mouthing words is just another form of this.",
"I've actually caught myself doing this to waiters/waitresses. I have a hard time hearing sometimes when they go over the specials for the day and I tend to mirror what they are saying as I read their lips. I've found that it helps me better understand what they are saying. "
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8u7qc3 | why does everything computerised need regular software updates now opposed to older models? e.g. my xbox one needs to update monthly(ish) while my xbox original never did (or could). | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8u7qc3/eli5_why_does_everything_computerised_need/ | {
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"Security is taken more seriously than it used to, particularly on consoles that are now much more online than they used to be (online multiplayer was a much newer thing for consoles during the xbox classic generation of consoles), and that are much closer to the computers we use every day. It was unlikely that your xbox would be an infection vector for viruses onto your home network, since it was a pretty shitty computer to run anything but games on; but your xbox one is more than capable, and it's probably connected to your network constantly as well.\n\nThreats are also constantly evolving; as more of the world becomes more computerized, there's more money to be made in cybercrime, and so organized crime and even some street-level gangs are making a move into digital theft and ransomware coding to get money. And no Microsoft or Sony or Nintendo-level company wants headlines about the latest ransomware that's exclusive to their console, so they keep a stream of updates that keep everything running.\n\nThe new and improved hardware also demands more complex software; more complex software means more bugs just by the very nature of coding, so bugfixes are near constant now.",
"Actually, the original Xbox DID have updates, but most people just received them via the disc, as opposed to downloading them. There weren't a whole lot of versions, though, and none provided major functionality changes. Mostly stability/anti piracy measures.\n\nIf you boot up your original Xbox and look at \"About this Xbox\" on the dashboard, it'll list the dashboard/system software version. Most recent is 1.00.5960.01.",
"The biggest reason is the rollout of 24x7 access to the internet. Before this was available internet access was limited to the times that you called in to your ISP modembank. These days your devices can access anything they want whenever they want, which means that the software providers are able to distribute updates whenever they want."
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34gcky | how can bernie sanders an independent be the democrats presidential nominee? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/34gcky/eli5_how_can_bernie_sanders_an_independent_be_the/ | {
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"He's not. He's seeking to be democratic presidential nominee. ELyou're5: he's hoping democrats will let him be leader of their club. "
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4x2gir | how do screenshots work from a software perspective? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4x2gir/eli5_how_do_screenshots_work_from_a_software/ | {
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"The software just saves the state of all the pixels that the hardware is sending to the display and puts it into a standard image format that other programs can then open. How the software actually gets the pixel data is platform dependent.",
"The graphics card has the current frame saved in memory as part of the standard process. It's called double buffering - one finished frame on display, one being drawn. So, when you take a screenshot the CPU just asks the GPU for the current frame and then places the data in the clipboard. \n\nWorth noting that requesting data from the GPU is much, much slower than sending data to it. For the most part there is very little need to get data back. ",
"First we need to accept the fact that computers don't really show us streams of moving objects. They show frame by frame, each stored in memory of the video card.\n\nWhen you play a game or watch a movie, the central processor of the computer is sending data and commands to the graphics processor inside your video card. The data might be a video stream, pictures or textures. Commands might be to tell to draw the video stream in a certain area or full screen; they can also be to construct 3D objects and use some pictures as textures, to put some lights in a distance, all kinds of transformations with those objects, commands to add fog and reflections, and so on. The video card will render that data into still frames, and send those frames one by one to the monitor. One of the commands the central processor can send to the video card is to send the latest rendered frame back. That will be the screenshot available in the computer memory. The rest depends on what software you used to take the screenshot. Built in functionality of video games usually saves the screenshot into a file on the local disk. Windows will put that screenshot into the clipboard and you can paste it into another program."
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1jhmmf | why are black holes invisible. | Ok, I've read alot on black holes, how they work, form and how we are detecting them. I pretty much read all there is on them in the Internet. However, one thing is not giving me peace. If a black hole "swallows" light, shouldn't they be visible by exactly that fact? I am aware of the gravitational lensing and stuff, but still why are they invisible and do not appear as black silhouettes in the sky? Yes, the sky is indeed black, but it is faaar from black for example in the galactic center of the Milky way. Thanks | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1jhmmf/eli5_why_are_black_holes_invisible/ | {
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" > If a black hole \"swallows\" light, shouldn't they be visible by exactly that fact?\n\nNo.\n\nThe reason you see objects is because light reflects off them and hits your eyes. If nothing reflects off an object (ie, if it were to perfectly absorb all incoming EM radiation, or have an escape velocity above the speed of light, like blackholes), you can't see it, because no photons are coming from it. All you \"see\" in its place is a black spot, which, as you've figured out, isn't all that different from the rest of the sky.",
"We can't see black holes for a number of reasons.\n\nThey each by definition have an event horizon around them, trapping all light inside from ever escaping and making them black in appearance. But as you pointed out, space isn't black.\n\nOne problem with seeing black holes is their distance. The nearest black hole is the centre of the Milky Way galaxy. Whilst it is a supermassive black hole (basically just a really, really big one) it is still many billions upon billions of miles away, and there are billions upon billions of stars between us and the black hole, which are obstructing our view of it. Even if we did have a clear line of sight to it and no light pollution, it is so far away it would be like trying to spot an individual grain of sand with your bare eyes from an airplane at cruising altitude. Even with the planet's best space telescopes they are very hard to see.\n\nAnother problem is gravitational lensing, which you mentioned. Becuase of this effect, all you would see when looking at the black hole is the image from directly behind the black hole. So instead of a pitch black spot on a close-to-black background, you would just see the star or galaxy that is behind the blackhole.\n\nSo visibly spotting a black hole is not very practical using technology available today. But how do we 'see' them?\n\nWhilst gravitational lensing means we can't spot a black hole directly, it does let us spot them indirectly. If a star of constant brightness suddenly appears to get brighter and stretch or change shape, before quickly returning back to its orignal form, we can conclude a massive object passed in front of it and caused gravitational lensing. Using various calculations we can work out just how massive that object was in each case, and if the mass is great enough we can assume it was a black hole that passed by.\n\nAnother method for detecting black holes is by looking at objects in space that seem to be orbiting around nothing. A star cannot be in orbit around empty space, there must be some form of gravitational source the star is orbiting around. Again, through certain calculations we can work out the mass of the gravitational source the star is orbiting around and see if it is heavy enough to class as a black hole."
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3mzzwp | what causes people to hallucinate when they get a very high fever, and is it the body trying to protect itself in some way? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3mzzwp/eli5_what_causes_people_to_hallucinate_when_they/ | {
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"when you have a high fever, enzymatic action all over your body begins to slow and in the brain, this causes an unbalanced level of certain neurotransmitters and other psychoactive compounds. when this occurs, hallucinations, stroke, and other odd feelings begin to surface",
"First time I ever hallucinated during a fever (that I can remember) was this past winter with a flu that lasted 13 days (I'm 35 and in great shape/health). \nGot it from my cousins kids....I swear all kids need to be quarantined during the months of October-April..... \nBut I digress...so the hallucination was crazy...I was babbling about something, but only one word would come out....and I would know this but I would keep babbling while knowing that to my wife I am making absolutely no sense, and I kept at it for a good while, just having a convo with myself.... \nI've tripped a lot before but this was completely different to any psychedelics i've tried. I knew I was in bad shape and needed to cool down and even wondered to myself how my wife could not be realizing that i'm burning up and need to be cooled down, but I never said anything to her or did anything about it myself and I was totally ok with that....come to think of it, the closest way to describe it would be a trip that is a mix of mushrooms and heroin/opium. \nOver all great experience, 10/10, would do again....but seriously, no, I do not want that to happen again...with a kid on the way i'm going to make sure I have buckets of ice on hand and a thermometer rammed up her rectum 24/7 in case this shit happens to her.",
"Is there any rhyme or reason to what I hallucinate? Because I thought I was a general in the Irish army. I dropped from 143 lbs to 134 that fever. Crazy time I had tossing and turning in bed commanding my troops.",
"When I was a child I had a fever. My hand felt just like two balloons. Now I got that feeling once again. I can't explain you would not understand. ",
"High temperatures, esp. over 101 F. and 39 C. cause the brain to malfunction. It's called encephalopathy, technically. This is what creates the hallucinations.\n\nWe get fevers to fight infectious diseases for one big reason. Living systems have enzymes and metabolic rates which are VERY sensitive to temps. Get cooled off too much the immune system stops working very well. The flu season often starts when average daily temps are below 50 deg. F. \n\nBut when body temps rise, the metabolic rates, esp. of the immune system can nearly double or more in speed of operation. This allows the body to mount a very much faster metabolic immune attack on diseases. thus doing in a few days what might take a week or longer.\n\nConsider that in fighting a new disease in the body, the body must create a series of antibodies to attack the newly recognized infectious agent, like a bacteria, or as below, a flu virus. It takes the body about 3 days to really get a good antibody series created which can detect, attach to, and direct killer cells to wipe out the infection over time. If it had to wait a week or longer to get that going, then the person could die. So it ups the metabolic speed by creating a fever which then shortcuts the normal rate substantially.\n\nalso there is a sort of a complex system computer in the immune system which can sort through something like 1 trillions potential antibodies to find the 1/ones which can attack the infection. No human computer can do that immense task of creating antibodies of that great number and simultaneously testing them for effectiveness. PLUS manufacturing the infection killers in high enough quantities to do the job. It's an amazing system, our immune system is, and we are lucky to have those. But then again, those who didn't, likely died quite some time ago....."
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bd7ucf | after suffering an injury, why are we told to elevate that part of our body over our heart? doesn't blood help heal the injured area and bring cells that heal it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bd7ucf/eli5_after_suffering_an_injury_why_are_we_told_to/ | {
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"Depends on how much blood we are talking about. Elevating the injury basically uses gravity to help overcome the blood pressure of that area, decreasing blood loss. I recall the story of a woman who cut her big toe - not a really horrible cut, but enough to produce a good amount of bleeding. Fearing the staining on her kitchen floor, she proceeded to wipe up the blood. As she moved backwards, wiping up the blood from her toe, she continued to bleed, so she continued to wipe. Being bent over and constantly moving, she eventually bled to death cleaning up her own blood. Had she just applied pressure and elevated her foot, she would have been fine.",
"Once you start swelling your blood vessels are squeezed. Arteries have the pressure of the heart to keep them open and flowing. \n\nYour veins are collapsed, and blood flow is restricted, because they don't have high blood pressure. By raising the damaged part you raise the pressure in the veins, which have an easier time draining toward the heart. Your lymphatic system, which is working hard as part of the healing process, also needs help with draining. \n\nIn addition, if you are bleeding elevation does help reduce blood pressure at the wound, and makes compression easier."
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5kln6a | usa mcdonald's franchise owners, operators or managers: what is the purpose of two drive through ordering points for one drive though window? | Every time I drive through a McDonald's restaurant with multiple drive through ordering boxes, I try to ascertain why this setup provides any advantage to the restaurant. My personal observations:
1) Lines are still just as long as under the old system
2) My order is always verified by the person taking payment as cars easily get out of order
3) Food receipt time, in my opinion, is as long or even longer than in previous years
4) The serving of the food limits the speed of the line, and ordering faster does not appear to decrease wait time.
I'd love to know the business case for this configuration.
Edit: Punctuation and formatting | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5kln6a/eli5_usa_mcdonalds_franchise_owners_operators_or/ | {
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"Data proves you wrong. Typically the slowest part of the average drive-thru is the ordering process. Customers unsure of what they want, large orders, etc. Years worth of data taken has proven this, that's why they have multiple ordering lanes. It's all about the number of cars they can get through, and having a backup lane maximizes that."
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46179m | when you're trying to sleep and you hear something, a flash or some tick in your eye that goes with the sound? | Example: I was trying to fall asleep, feeling pretty comfortable and heard my dog get up off the floor. When I heard that the sound it made a quick light while my eyes were still closed appear.
Hopefully this makes sense, thank you! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/46179m/eli5_when_youre_trying_to_sleep_and_you_hear/ | {
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"Chances are you were transitioning into sleep. During this time, many people are prone to a phenomenon called \"hypnogogia\". This can range anywhere from auditory hallucinations such as hearing voices or phones ringing, to visual hallucinations involving dancing blobs or waves of color to seemingly bright flashes.\n\nIf you'd like to know more, check out [this link](_URL_0_)\n\nPersonally, I hear conversations and see color waves mostly. The conversations don't usually make sense. One time I heard a song I really like while my favorite professor passionately lectured while a bunch of demons flew around the room screaming. It can be quite strange, but if you go along, it can be quite a ride.\n\nEdit: Fixed link."
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1u79m5 | the barn-pole relativity paradox | Say we have someone hold a pole of length L. A farmer has a barn of length (3/4)L with gates on either side. The farmer bets the pole vaulters that he can make the pole fit entirely inside the barn horizontally. He asks the vaulter to run into the barn with speed (sqrt3/2)c, so the pole contracts relativistically to only (1/2)L and thus fits when the gates are instantly closed according to the farmer. The vaulter, however, observes the barn contracting by a factor of 2, so the pole does NOT fit inside when the gates are closed.
Can someone help me understand the resolution to the paradox? Is the Lorentz contraction "real" in this problem? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1u79m5/eli5_the_barnpole_relativity_paradox/ | {
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"Lorentz contraction is always \"real\", but the point is that it's *relative*. The farmer sees the entire pole in the barn, while the runner doesn't (how could he, since for him it's *the barn* that's contacting).\n\nThe resolution of the \"paradox\" comes from carefully considering what we mean when we say \"the pole fits in the barn\". This is shorthand for saying \"the front of the pole exits the back of the barn *after* the back of the pole enters the front of the barn\". So really, when we talk about fitting the pole in the barn, we're taking about the space-time interval between two events. The paradox is resolved because relativity also dictates that the different observers will not agree on the relative timing of the events. \n\nTLDR; Relativity requires us to rethink simultaneity"
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6o3dh6 | did the musical notes we all know (d,f,g,f-sharp etc.) basically *have* to be or was this just one person's selection that ended up working well? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6o3dh6/eli5_did_the_musical_notes_we_all_know_dfgfsharp/ | {
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"Look at a violin. It has no frets. Violin players play by ear and get it right. So do Bass and viola players. Look at a guitar. It has frets. Guitars have to be tuned. But once tuned they can be played by holding strings down on the frets.\n\nWe need to define what one note is, how many cycles per second. Double that frequency plays the note again an octave up. Halve the frequency and you get the note again an octave lower. \n\nThe other notes are standard ratios away from the first note. Playing the right notes together as a chord is pleasing. They are a certain distance apart by ratios, when played. So they alternately resonate together.\n\nSo once the first standard tone is selected. It is world wide now and easy to tune to, the other notes can be defined.\n\nThat is the simple explanation. When you get more complex you can study [music theory](_URL_0_) and how a piano is a compromise. String instruments are not.",
"Here's the really short explanation: the notes are based in part from ratios between the different notes. For example a note and an octave higher will have a 1:2 ratio, where a note and it's fifth will have a 2:3 ratio.\n\nAgain to summarize, over hundreds of years we figured that having 7 notes made music that sounded very pleasant and we just gave these notes the name A, B, C, D, E, F, G. Other countries have different names for these 7 notes. Think of the white keys on the piano.\n\nHowever transposing these notes up and down and using the circle of fifths, you can sort of cheat and create an arrangement of 12 notes that allows different combinations of 7 notes for many keys. We have to fill in the blanks so we create flats and sharps between the white notes. These are the black keys on the piano.",
"Sound is vibrations and we attribute the frequency of those vibrations a pitch. When certain combinations of frequencies are combined, they may blend together well or not.\n\nFor example, if you have a note with vibration of 256 Hz, and you play a 2nd note with a frequency of 512 Hz, then you get a 1:2 ratio of vibrations, and the two go together really nicely. In general, people call them the same note, but at a different \"octave\"; in this case, 256 Hz is by convention called \"middle C\", and 512 Hz is C one octave above middle C.\n\nBut what about the other notes? Where did they come from?\n\nIt turns out that 1:2 isn't the only ratio that works nicely. 2:3, or 3:4 or 4:5 or 3:5 something similar give pleasing sounds when played together. \n\nSo, if you combined 256 Hz with 320 Hz, that's a nice combination; or 256 combined with 320 and 384 Hz in a 3 note chord is also a nice combiation.\n\nSo, how could you define lots of different notes which made up all these different ratios? One way, would just be to have a 4:5 ratio (320), a 3:2 (384) and so on - and then repeat everything after doubling or halving (640, 768 - or 160, 192). The problem with this, is that the \"gaps\" between the notes are all different - so you can't just take a piece of music and shift it a little bit lower, or a little bit higher.\n\nEventually people worked out, that if you divided the doubling interval into 12 equal steps (each note is 1.06 * the one before - so 256, 271, 287, 304, 322, 341, 362, 384, 406, 431, 456, 483, 512) - you could get close to lots of nice ratios (you can see the 322 which is very close 4:5, 384 which is exactly 3:2, 287 which is very close to 3:4, 431 which is close to 3:5).\n\nThis gives you 12 equally spaced notes with a ton of really nice ratios which can be combined together in nice chords, while at the same time being easy to use with equal notes.\n\nIf you dig down into the ratios - you'll see that starting from \"C\", the white keys on the piano correspond to the nicest ratios - D is 7:8, E is 4:5, F is 3:4, G is 2:3, A is 3:5, B is 8:15; the black keys are in between ratios for example D# is 16:19.\n\nSo it all comes down to discovering that dividing an octave into 12 equal steps results in a lots of nice combinations that \"just work\". People realised that the nicest ratios weren't equally spaced (for example F is next after E, but D has a note between in and C), and that's why there's no E#.\n\nAs to why 256 Hz might be used - there's no real reason. You can choose any reference you want. In fact, people often tune to concert A (440 Hz) which requires a slightly different tuning.\n\nJust one final point: modern tuning normally tunes instruments so that the spacing between the notes is exactly equal. But, as I pointed out above, this doesn't exactly match the nice round number ratios. Historically, instruments were often tuned to give the exact ratios; the tuner would listen to the two notes together, and they'd be in tune when you got the nicest sounding chord. This type of tuning would give nice pure sounding chords and harmony - but this lead to the gaps between the notes not being quite even, and resulted in certain combinations of notes having completely off ratios and sounding weird and clashing (called a Wolf interval)",
"Historically the names of the notes change over time.\nThe root choice for the names of the notes of the western 12 note scale are arbitrary. What is important however it is that all instrument manufacturers at least AGREE on the arbitrary names of the notes. \n\nThe IOS (International organization for Standardization) set the tuning of middle \"A\" to 440 vibrations/second in the early 20th century. This standard is called \"A-440\". It has not always been the case however and pitch changes a lot throughout history.\n\nMozart's \"A\" for example was nearly a semi-tone lower than what we would call an A today. It sounded closer to a G-sharp than an A. If you tried to play a flute from the 18th century with a modern orchestra, you would need to transpose in order for it to work. His names of the notes were indeed different.\n\nStandard pitch really does rise over the years. \"A\" was closer to 428hz at the end of the 1800's, while some orchestras around the world today are tuning as high as A-445. That's a HUGE difference.",
"In addition to what others have said, here are some notes and their corresponding frequencies. The ratio from one frequency to another is always 1.05945....\n\n\n C0\t16.35\t\n C#0\t17.32\t1.0594630944\n D0\t18.35\t1.0594630944\n D#0\t19.45\t1.0594630944\n E0\t20.60\t1.0594630944\n F0\t21.83\t1.0594630944\n F#0\t23.12\t1.0594630944\n G0\t24.50\t1.0594630944\n G#0\t25.96\t1.0594630944\n A0\t27.50\t1.0594630944\n A#0\t29.14\t1.0594630944\n B0\t30.87\t1.0594630944\n C1\t32.70\t1.0594630944\n C#1\t34.65\t1.0594630944\n D1\t36.71\t1.0594630944\n D#1\t38.89\t1.0594630944\n E1\t41.20\t1.0594630944\n F1\t43.65\t1.0594630944\n F#1\t46.25\t1.0594630944\n G1\t49.00\t1.0594630944\n G#1\t51.91\t1.0594630944\n A1\t55.00\t1.0594630944\n A#1\t58.27\t1.0594630944\n B1\t61.74\t1.0594630944\n C2\t65.41\t1.0594630944\n C#2\t69.30\t1.0594630944\n D2\t73.42\t1.0594630944\n D#2\t77.78\t1.0594630944\n E2\t82.41\t1.0594630944\n F2\t87.31\t1.0594630944\n F#2\t92.50\t1.0594630944\n G2\t98.00\t1.0594630944\n G#2\t103.83\t1.0594630944\n A2\t110.00\t1.0594630944\n A#2\t116.54\t1.0594630944\n B2\t123.47\t1.0594630944\n C3\t130.81\t1.0594630944\n C#3\t138.59\t1.0594630944\n D3\t146.83\t1.0594630944\n D#3\t155.56\t1.0594630944\n E3\t164.81\t1.0594630944\n F3\t174.61\t1.0594630944\n F#3\t185.00\t1.0594630944\n G3\t196.00\t1.0594630944\n G#3\t207.65\t1.0594630944\n A3\t220.00\t1.0594630944\n A#3\t233.08\t1.0594630944\n B3\t246.94\t1.0594630944\n C4\t261.63\t1.0594630944\n C#4\t277.18\t1.0594630944\n D4\t293.66\t1.0594630944\n D#4\t311.13\t1.0594630944\n E4\t329.63\t1.0594630944\n F4\t349.23\t1.0594630944\n F#4\t369.99\t1.0594630944\n G4\t392.00\t1.0594630944\n G#4\t415.30\t1.0594630944\n A4\t440.00\t1.0594630944\n A#4\t466.16\t1.0594630944\n B4\t493.88\t1.0594630944\n C5\t523.25\t1.0594630944\n C#5\t554.37\t1.0594630944\n D5\t587.33\t1.0594630944\n D#5\t622.25\t1.0594630944\n E5\t659.26\t1.0594630944\n F5\t698.46\t1.0594630944\n F#5\t739.99\t1.0594630944\n G5\t783.99\t1.0594630944\n G#5\t830.61\t1.0594630944\n A5\t880.00\t1.0594630944\n A#5\t932.33\t1.0594630944\n B5\t987.77\t1.0594630944\n C6\t1046.50\t1.0594630944\n C#6\t1108.73\t1.0594630944\n D6\t1174.66\t1.0594630944\n D#6\t1244.51\t1.0594630944\n E6\t1318.51\t1.0594630944\n F6\t1396.91\t1.0594630944\n F#6\t1479.98\t1.0594630944\n G6\t1567.98\t1.0594630944\n G#6\t1661.22\t1.0594630944\n A6\t1760.00\t1.0594630944\n A#6\t1864.66\t1.0594630944\n B6\t1975.53\t1.0594630944\n C7\t2093.00\t1.0594630944\n C#7\t2217.46\t1.0594630944\n D7\t2349.32\t1.0594630944\n D#7\t2489.02\t1.0594630944\n E7\t2637.02\t1.0594630944\n F7\t2793.83\t1.0594630944\n F#7\t2959.96\t1.0594630944\n G7\t3135.96\t1.0594630944\n G#7\t3322.44\t1.0594630944\n A7\t3520.00\t1.0594630944\n A#7\t3729.31\t1.0594630944\n B7\t3951.07\t1.0594630944\n C8\t4186.01\t1.0594630944\n C#8\t4434.92\t1.0594630944\n D8\t4698.64\t1.0594630944\n D#8\t4978.03\t1.0594630944\n E8\t5274.04\t1.0594630944\n F8\t5587.65\t1.0594630944\n F#8\t5919.91\t1.0594630944\n G8\t6271.93\t1.0594630944\n G#8\t6644.88\t1.0594630944\n A8\t7040.00\t1.0594630944\n A#8\t7458.62\t1.0594630944\n B8\t7902.13\t1.0594630944"
]
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2kvcmq | why is direct democracy not a viable system as opposed to what we have? would it result in massive indecisiveness, if implemented? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2kvcmq/eli5_why_is_direct_democracy_not_a_viable_system/ | {
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"Two main problems with direct democracy I can think of off the top of my head:\n\n- stability: the will of the masses tends to change quickly. News report on minor being raped and killed? Let's introduce death penalty. Mass shooting? Let's forbid guns. Note I'm not taking a stand towards either death penalty nor gun control; just pointing out that recent events will have a major influence on policy in a direct democracy, and that's rarely a good thing.\n\n- power distribution: media influence plays an even higher role than it already does, pretty much for the same reason as above - it can easily sway public opinion.\n\nThis is really a question better suited for /r/askreddit.",
"It would result in what's called the tyranny of the masses (or \"mob rule\"), as the popular majority tramples on the wishes and needs of the minorities.",
"Switzerland, with around 8 million citizens, has a limited but very viable version of direct democracy. It has worked well for a long time, with citizens voting on various issues four times a year. \nOn the federal (country) level, anyone who can gather 50 000 votes within 100 days can force a national vote on whether or not to block specific legislation introduced by parliament. If you can gather 100 000 signatures within 18 months, you can force a national vote on whether or not to introduce changes to the constitution. \nOn the regional (cantonal) and county/city (communal) level, there is even more direct democracy, and citizens can introduce suggestions which will be voted on at the next town meeting.\n\nThe end result of all this is debatable, but what is certain is that Switzerland has become a very succesful country with low taxation, comparatively few bureaucrats, a strong industrial base, and possibly the best health care system in the world."
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3fhurf | how can the us government tack on extra laws to bills? | I was watching the news and I saw a story about Rio Tinto opening a new mine in Arizona but the native Indians were protesting it because the land had cultural value.
Back in the 50's President Eisenhower passed a law protecting the grounds but a while back a law was sneaked into a bill about military spending which needed to be passed that overruled the law Eisenhower set out. This isn't the first I've heard of it either.
So my question is, How can the government sneak extra (usually controversial) laws into completely unrelated bills without public consultation? Doesn't it defeat the purpose of a democracy? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3fhurf/eli5_how_can_the_us_government_tack_on_extra_laws/ | {
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"People in the US don't vote on every bill that is to/might become law. It is a Representstive Democracy so they vote for Senators and Congresmen/women who will they represent them. It is these people who then vote on the bills which are put before them. If the bill passes in both the Senate and the House of Representatives the president will sign that bill and it will become law. Each bill is not limited to one topic. It is quite often that a bill will be mostly about one topic that everyone can get on board with, and then have a line or section which covers something entirely different. Typically the subject of that provision is something one or the other parties does not particularly want. "
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70clmz | how does recycling paper work and why does it seem like every recycled paper bag is brown? | I got a present that was in a Whole Foods bag that said "This bag is made from 100% recycled paper and is completely recyclable." How do my old mail and papers and things become this bag and why do all these recycled bags and things tend to be brown? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/70clmz/eli5_how_does_recycling_paper_work_and_why_does/ | {
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"Paper is recycled by chopping it up and then cooking the bits in warm water, then mashing them back into sheets and drying it again.\n\nUsually they bleach it, so most recycled paper is white. If they don't bleach it, the natural color is gray or brown depending on the materials. (Brown if made of cardboard boxes, gray if made of office paper or newspaper.)"
]
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|
10rre5 | why will a whole flock of birds sit in a tree and caw/chirp/exclaim at seemingly nothing? | Saw a big tree just full of black birds the other day - crows, I'd imagine? - and they were all just crowing away. There was nothing around, but I could hear them long before/after I'd walked past the tree. I understand birds making sounds to alert others or otherwise communicate, but what prompts them to all just sit in a tree and make noise seemingly for the heck of it? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/10rre5/eli5_why_will_a_whole_flock_of_birds_sit_in_a/ | {
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"Birds do four very basic things: Eat, sleep, shit and fuck. If the birds have eaten and got enough rest there is nothing left for them to do but try to get with the lady birds. Birds hang out in trees and chirp and sing to show that they have done all the important things and they would be a good choice for a marathon sex session because they are such efficient hunters and sleepers, they must be better than the other birds. Trouble is, once one bird starts making noise, others join in even if they are a bit hungry. Soon all the birds are cawing and whistling outside your door. ",
"There are other reasons to communicate than danger. Social hierarchy, mating selection, etc."
]
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2jtbtu | why are there leaked pictures of almost all new non-released products? how do they get them? | Products like Apple iPhones, gaddets and stuff like that... Companies do this on purpose? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2jtbtu/eli5why_are_there_leaked_pictures_of_almost_all/ | {
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"1. an insider (employee, someone in the production line / supply-chain line) sells the information to a publisher.\n\n2. the company itself tries to mimic the hype of \"leaks\" by willfully creating the above for the purpose of marketing.\n\n",
"To announce a new product, it generally helps to have promotional materials already made - stock photos, spec sheets, comparison charts. Also a prototype likely needs to already be made, or even thousands of units may have already been produced and ready to hit shelves. \n\n If you're going to announce a new iPad, you should release the size/dimensions to the authorized case and peripherals manufacturers so they have time to create add-on products. If you're releasing a new version of Windows, you should have a beta version that software developers can make sure their products run on.\n\nAt some point in the process, despite being expressly forbidden from leaking the information, someone decides to sneak it out and expose it. I don't believe \"most\" is \"done on purpose.\" Some of it might be. It's more likely that when you have dozens, hundreds, or thousands, of people working to release a hugely anticipated product, someone is going to leak. \"Two can keep a secret if one of them is dead.\""
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4eul5r | how do doctors know the type of cancer someone has when it's metastatic? | Ex. My father had "metastatic colon cancer" Ty! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4eul5r/eli5_how_do_doctors_know_the_type_of_cancer/ | {
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"You can obtain a sample and look in the microscope. Colon cancer mostly occurs in the outermost most layer of the GI tract called epithelial layer and the surrounding connective tissue. The best way to see if it is spreading is by checking presence of cancer cells in areas below the epithelial layer. Cancer cells are often huge and have pretty big nuclei and look nothing like the cells around them. \n\nAnother way is to obtain a tissue sample from the nearest lymph node. Lymph vessels drain the area around cells so they are a easy pathway for metastasis. Lymph vessels drain into lymph nodes so you can biopsy a lymph node to see if there are any cancer cells there. \n\n",
"Sometimes they don't. There are ways to tell, taking biopsy and examining the cells from the secondary tumours but often it's not practical or helpful and it depends on the individual case.\n\nMy father was diagnosed with liver and lung cancer but we were told that they didn't know where the primary tumour had came from. \n\nIn such cases it's often referred to as [cancer of unknown primary] (_URL_0_).\n\nAs with your own dad, my dad almost certainly had a primary that was colorectal. It was never confirmed officially though but from the information we have it seems the most logical. I'm not a clilnician but I worked for the hospital at the time and was given advice and information by the Consultants and Professors that I worked for.\n\nI'm very sorry to hear that your father had metastatic colon cancer. \n\nSometimes it isn't practical to look for the primary. It depends upon a lot of factors and every case is different.\n",
"That cancer has metasticized tells them what stage it is in. Cancer has 5 stages, though it's usually diagnosed in 1 of 4 stages. They are: \n\nStage 0: 'In Situ'. A cell that becomes malignant usually does so in the company of other, similar cells. It can stay in that position, in a single tumour in a single spot. This is *in situ* cancer. \n\nStage 1: Localized. In this stage the cancer cells gain the ability to pass through the 'basement membrane' that the boundary to the tissue in which the cancer cells began, invading neighboring tissue as they do. This is a serious step, because while some *in situ* cancers never progress, this step means that this particular cancer means to do just that, progress, and continue to grow. While the cancer may be a single lump, it is considered localised. \n\nStages 2 & 3: Regional Spread. Once a cancer has invaded the surrounding tissues, the next common step is for one of it's 'daughter cells' to invade through a lymph vessel. A lymph vessel is like a blood vessel but instead of blood, it carries a clear fluid called lymph, which is constantly exuding from our capillaries back to the blood stream. As it travels to the blood stream, this fluid passes through a lymph node, one of the major players in our body's immune system. When the cancer cells reach the lymph node, they may provoke an immune response against them, which may destroy them and other cancer cells. This is a best case scenario. More often, though, the cancer cells begin to divide and form a new lump in the lymph node. This stage is regional spread. Thi sis to say, the cancer has spread to the general region where it first began, but not to other parts of the body. Whether it is stage 2 or 3 depends on how many lymph nodes the cancer has reached. \n\nStage 4: Distant Spread; Metastasis. The cancer cells have multiplied in the lymph nodes and are now spreading through the lymph and blood systems to other organs. Once they begin growing in another organ, that is metastatic cancer. This is the latest stage of cancer, and hardest to treat because it involves treating multiple parts of the body. \n\nHave they told you where the cancer has spread? Colon cancer tends to hit the liver, but sometimes the lungs or peritoneum (lining of the abdominal cavity). If the metastases are small, and they know where they are, then surgery *may* be an option to give him more time and possibly even provide a cure. Chemo is usually done in conjunction with the surgery, before and/or after. \n\nI am really sorry for your dad, and I hope his prognosis is a good one. "
]
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"http://www.macmillan.org.uk/cancerinformation/cancertypes/unknownprimary/unknownprimary.aspx"
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Subsets and Splits