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7al3ec | why is the inside of a refrigerator cold, but the sides hot? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7al3ec/eli5_why_is_the_inside_of_a_refrigerator_cold_but/ | {
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"Refrigerators cool your food by pumping heat energy out of the inside of the fridge. They then dump that heat into the air around the outside of the fridge, typically from the back of the unit. As long as the fridge has sufficient insulation, the heat doesn't really get back in.",
"Refrigerators and air conditioners work by moving heat from one area to another. While an air conditioner moves it from indoors to outdoors, a refrigerator moves it from inside to the outside. Some use the sides to dissipate the heat. Others use the rear or bottom. ",
"When you compress a gas, it heats up. When you expand it, it cools down. But this doesn't change the energy in it.\n\nYour fridge has some gas in it, like freon. It expands that gas until it's colder than the inside of the fridge and pumps it inside. Heat flows from your food into the freon, removing energy from the food and adding it to the freon. Then the fridge pumps the freon out and compresses it. Now it's hotter than the room, and it can cool off, warming your room.\n\nThat makes the inside of the fridge cold and the outside warm.",
"This is like asking why the space on one side of the broom is clean and the other side is dusty. The broom has moved the dust. That is it's purpose. Similarly, the fridge has moved the heat. That is its purpose. "
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5uzb9i | for massive websites like amazon or google, how are they built, scaled to a large size, and maintained? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5uzb9i/eli5_for_massive_websites_like_amazon_or_google/ | {
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"Well I am a web developer at the opposite end of things to Amazon and Google. If websites were ships those guys are making supertankers and aircraft carriers while I am making kayaks so I can't claim the expertise to actually build things like that but maybe I have enough grasp of the concepts to try a high-level ELI5.\n\nSo first of all imagine a small 'normal' website. Imagine I build an online book store. On the homepage it might have a bit in the top corner saying: Hello rokd, with a link to manage your account/profile.\n\nThe main section has a list of this week's 20 top-selling books and on the right is a column with teasers from a blog where I highlight my personal favourite authors.\n\nAt the most simple level I have one database storing all the stuff I need. It has a table for users (including rokd), a table for books, one for sales, one for blog posts.\n\nI then have one script/executable page of code which gathers all the information and assembles in, something like:\n\n > < header > \n > print link_to_user_profile(getCurrentUser) \n > < /header > \n > < main > \n > print get_recent_bestsellers(20, week) \n > < /main > \n > < sidebar > \n > print get_recent_blog_items(5) \n > < /sidebar > \n\nThis is all well and good but this one script running on one computer and one database running on one computer is doing everything for this page, and every other page served to every other user. So the only way to scale is to make those computers really really powerful and at google levels even a supercomputer isn't enough.\n\nSetting aside that problem completely for a moment, let's imagine I didn't want to bother building a blogging system for my bookshop because wordpress already exists and why invent the wheel. So I get a site at _URL_1_ and I change my page to something like:\n\n > < sidebar > \n > print ask_remote_server_for_something(server=_URL_1_, account=somersettlerbookshop, request=latest_blog_posts(5)) \n > < /sidebar > \n\nSo now my blog posts are being stored and rendered somewhere else. I just make an API call to _URL_1_ and ask for something, it supplies the answer, I don't even know or care exactly what database my blog posts are stored in, or what script on what computer renders the data into html. So long as _URL_1_ tells me what I want I don't have to give a shit how it does it.\n\nWell what Jeff Bezos famously did in 2002 is [issue an edict](_URL_0_) that all teams in amazon had to built their shit to talk to each other in the same way as I talk to wordpress in the example above. Even though they are within the same company, and even though, at small scales, their code might be running on the same computer, they always had to pretend they were totally separate and only communicate through remote services and APIs.\n\nSo I change my code to something like \n\n > < header > \n > ask_remote_server_for_something(server=user_subsystem, request=link_to_current_profile(currentuser)) \n > < /header > \n\nAnd so on for every element of my site. That way separate tasks can be split across separate computers. So 1 computer just runs the books stuff, 1 for the user stuff, 1 for the blog stuff, 1 for the sales, and 1 to coordinate all the requests and piece it together in a single page for the user.\n\nNow, we might add some cacheing. For example, I only write a new blog post every couple of days. So if you load my page at 9.00pm, then refresh at 9.05pm, at present, we are loading all my blogs from the database and rendering them all over again, even though nothing has changed. Our get_latest_blog_posts code might look like this:\n\n > blog_raw_data = get_recent_blogs_from_database(5) \n > rendered_blogs = render(blog_raw_data) \n > return rendered_blogs \n\nWaste of resources. So I can tell it to cache the results of a request and only re-calculate it if a certain amount of time has passed, say, 24 hours. The code changes to something like:\n\n > if (more than 24 hours has passed since I was last asked) then \n > > blog_raw_data = get_recent_blogs_from_database(5) \n > > rendered_blogs = render(blog_raw_data) \n > > cached_blogs = rendered_blogs\n > > return rendered_blogs \n > \n > else \n > > return cached_blogs \n\nNote that my top level page doesn't know or care about this change. It just asks for blogs, and it gets blogs, it doesn't matter to it whether they came from a cache instead of from a database.\n\nNow let's imagine my website needs to scale even more. It's a bookshop, so books is the hardest-working subsystem I have, and 1 computer is not enough to run it any more.\n\nSo we changed \n\n > print get_book_information(bookID) \n\nto\n\n > print ask_remote_server(server=books, request=book_information(bookID)) \n\nBut now we need several servers: books1, books2, books3. So make it something like\n\n > print ask_remote_server(server=find_me_a_books_server, request=book_fnformation(bookID)) \n\nand have another server in the middle, called a load balancer, which keeps track of whether books1, books2 or books3 has capacity to service a request, and sends it on accordingly. Once again our top level page doesn't know or care which of the 3 books servers answers the request, so long as it gets an answer.\n\nBasically we keep breaking our software down into self-contained 'black boxes' which communicate with each other through defined protocols, and that way if we outgrow 1 server we can use 2, or 3, or 300, on different continents.\n\nStill, we can't scale perfectly, because if I'm running my bookshop on 20 servers, and it maxes out, then while my _software_ is capable of seamlessly extending across 30 servers, I can't just wave a magic wand and have 10 new PCs in my racks, all wired up to my network. That takes time. But I want my site to suddenly have twice the capacity if it gets linked from reddit. By the time I get the new servers physically installed the reddit traffic has gone.\n\nSo we invent virtual servers, where an entire physical server is virtualised in software within a more powerful actual server, capacble of hosting multiple virtual servers.\n\nAnd we take our find\\_me\\_a\\_server code, which used to say: \"Hey, books1, are you busy? Hey books2, are you busy?\" and hand the request to whichever server said \"no\" - and we change it so that if _all_ the books servers say \"sorry, I'm busy\", it just creates a new books4 server on the fly.\n\nOnce we get used to coding in this distibuted fashion we can also rewrite our algorhythms to take advantage. So rather than simply separating the \"books\" workload from the \"sales\" workload, we can also improve performance of a particularly taxing sales data processing task by splitting that into parallel tasks across multiple servers. google's map_reduce is an example of this sort of thing but getting a bit out of my depth / scope of this answer to explain that in detail.\n\nThere's another whole category of scaling around databases. Most traditional databases are 'ACID-compliant', and 'normalised'. Again this comment is getting way too long for me to go into detail on that but basically they are ways of ensuring your data does not get corrupt.\n\nSay for example my bookshop is extremely busy. As you visit the homepage the code asks the sales system for the top 20 bestsellers. It returns the #1 seller, _Harry Potter_ with 150 sales in the last week (narrowly ahead of the #2, _Bambi_ with 149 sales). While it does this, three people buy a copy of Bambi and one person buys Harry Potter. My code then proceeds to tell you that the #2 seller is Harry Potter with 151 sales (because the #1 is now Bambi with 152).\n\nSo your list is \n\n1 Harry Potter 150 sales \n2 Harry Potter 151 sales \n\nWTF? Looks like my system is fucked, right? Traditionally databases avoid this through ACID compliance, so the database is locked while a transaction is made to ensure consistent results. Simplistically, this would mean while you are generating the list of bestsellers, nobody else can buy a book, because that would change the results. But everybody visiting my homepage generates that bestseller list. If nobody can buy while someone is looking at the homepage, I'll never sell any books. Customers will always get a \"database locked, cannot purchase!\" error and give up and go to Amazon... \n\nSo some people realised, it doesn't actually _matter_ if your bestseller list is based on the most accurate and up-to-date data. If it's based on sales as of 5 minutes ago, that's fine, then we can carry on selling. We can tell you Harry Potter is #1 when it is actually Bambi #1 since we made a few sales a millisecond ago - who gives a shit? On the other hand it _does_ matter if we tell you we have 10 copies of Bambi in stock when we actually have zero left, since we made a few sales a millisecond ago.\n\nSo people started carefully breaking down which parts of the database required traditional 'safety' / consistency / anti-corruption guarantees, and which parts didn't. And for the parts that didn't, by selectively adding caches, splitting amongst parallel systems, denormalisation, abandoning ACID-compliance, or even abandoning SQL paradigms completely, they could get more performance.\n\ntl;dr distributed computing, parallelisation, cacheing, load balancing, virtualisation, denormalisation, nosql"
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8jtq68 | why does it seem like it’s impossibly harder to fall asleep when you’re sleeping with someone and cuddling? | It might just be me, but I’ve noticed that the person I’ve been sleeping with (non-sexually) and myself have a hard time falling asleep if we’re all tangled up. It’s like we’re consciously sleeping or something. Real strange. I was just wondering if there’s a know reason for it. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8jtq68/eli5_why_does_it_seem_like_its_impossibly_harder/ | {
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"Mostly comes down to being in a new situation\n\nFor years you have been sleeping alone and so the body has grown use to being able to move freely in bed without contact another person. \n\nHowever, evolution still dictates (most of) us to be on high alert when sleeping in case some predator begins to attack. Even though we consciously know the person next to us is no danger, the body still senses that the sleeping conditions are not what it is use to, therefore that other person must be a danger and we should stay awake to make sure they dont try anything",
"Not for me. Cuddling up to my wife is a trigger for me to sleep. I can literally fall asleep within minutes when I curl up to her. ",
"You're probably just not used to sleeping with someone else in your bed, or you have a small amount of social anxiety/awkwardness/discomfort, causing your brain to release adrenaline and other neurotransmitters that keep you awake. Or you might be sexually aroused by being so intimately close to someone\\(especially since you're not having sex\\), which triggers the release of those same neurotransmitters that keep you awake.\n\nIf you slept with the same person every night for a long time, you would probably begin to fall asleep very easily while cuddling\\(I'm assuming you started sleeping with this person relatively recently\\). You might even have insomnia when your partner *isn't* there."
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5naes6 | "discipline" | I have recently heard the saying "Where motivation ends, discipline must take its place", and tried applying this in real life, but noticed that I don't really have a clue what discipline is, and where the difference between discipline and determination is. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5naes6/eli5_discipline/ | {
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"Basically, in this context 'Discipline' is the ability to keep at it and stick to the plan despite how much you have lost interest in it.\n\nOne can be determined to finish something, but that can be worn away very quickly if it is not reinforced with discipline.\n\nEdit: In many ways, determination is synonymous with motivation."
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ctfng6 | what actually is reflection? | I never understood what reflection is from a physics perspective. Is it "photons just bouncing off the atoms or whatever particles it hits (and reaches our eyes)?or "Is it that, particles absorb and remit photons"? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ctfng6/eli5what_actually_is_reflection/ | {
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"Its kind of like they bounce. Sort of.\n\nWhen light interacts with electrons in metals it caused those electrons to move. Since electrons in metals are free to move around in whatever direction the electrons are wiggled pretty much uniformly. Just like light can cause electrons to oscillate, oscillating electrons can create light. But when those multiple elections oscillate the light created constructively and destructively interferes so that the outgoing light is only emitted in the direction you expect light to be emitted.\n\nIts really hard to think about it in terms of photons. This is one of those weird particle interferes with itself wave things. The individual photon isn't actually absorbed, it just kind of bounces because that's what should happen if it were a wave."
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21wjab | when the tide is high on one coast, is it low on the opposing, parallel coast? | ..or does the ocean just thin out in the middle? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/21wjab/eli5_when_the_tide_is_high_on_one_coast_is_it_low/ | {
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"The tide will be high where you are as well as the opposite side. It will be low between that. This is a little too simple though, because both the sun and the moon are affecting it. Sometimes you'll see a complete tide cycle with little actual change, sometimes it's a huge swing, just depends how the two are interacting.\n\nSource: diver. Tide is your frenemy."
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3c3yko | how did they develop games for the nes/snes? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3c3yko/eli5_how_did_they_develop_games_for_the_nessnes/ | {
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"In the corresponding assembly language. Back then there weren't really C compilers for for 8 or 16 bit micros. Not to mention these devices had very little memory and CPU performance available, so you had to squeeze out every bit you could. This involved a lot of cheap hacks to manipulate the hardware that wouldn't be possible using a higher level language. ",
"As a person who develops for NES, they used terminals that basically edited text documents. The process is somewhat similar today, except that there's no fancy compiler and linker, no 1080p screen resolution, fancy graphics editors with undo and redo and 10 tabs. No space limitations today either, no worries about RAM restrictions because large RAM is cheap today, etc.\n\nThe code is mainly just a text document. It has all the processor operations like ADC, add with carry, JMP, jump to a place in code, etc. It's basically the same as it is today, just without all our fancy notepad features. Just write the code, use an assembler to assemble your code for that assembler into the \"data blobs\" you need and you can load it into an emulator to test/play it, or a system, etc. That's basically all there is to it.\n\nLater on, some companies might have had personal computers that had software, and an interface and they started to make those tools themselves, but in the hey day, it was mainly text terminals, maybe a special computer to make/show graphics, and that's about it. SNES they did the same, just on a much bigger, more complex, scale. And probably had GUI software to help, to a point. But a lot was still done with just writing assembly code up to the N64.",
"Once the code was written how was it tested on the console? "
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20q0qb | why does quebec want to secede from canada, and what are the implications of it does? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/20q0qb/eli5why_does_quebec_want_to_secede_from_canada/ | {
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"Quebec wants to leave Canada because of a long running divide between the English speaking majority and the French speaking minority. The roots of this go back to colonization, during which the English defeated the French and kicked them off the continent, more or less.\n\nQuebec considers themselves to be culturally unique, to the point where they pushed for recognition as a 'country within a country'. They believe by seperating, they will be able to better protect their cultural identity and achieve greater independence from the Anglo ruling class who holds them back.\n\nIn reality, there is no such conspiracy. Should Quebec leave, they'll also leave with a substantial debt and faltering revenue -- currently, the province relies on transfer payments from the other provinces to maintain the balance sheet.\n\nThey have a pipedream that they'll be able to access the rest of Canada without a passport, that tourism dollars will actually flow into Quebec and that they'll be able to continue using the Canadian dollar with a seat at the Bank of Canada. So far, none of these seem to be realistic expectations.\n\n50/50 odds that within 20 years, the country of Quebec would be bankrupt and rejoin Canada out of desperation; 60/40 we invade them within the century and annex the territory.\n\nOn a practical note, they are unlikely to be able to pass the referendum: current levels of support for separatism are around the same levels they were in the 1980s -- substantially lower than their last vote [1994?]. There is also the complexity of dealing with the Natives and their treaty rights, who would likely side with the Federal government, and the Anglo-Quebecois who will never vote for separatism.",
"Its not all of Québec that wants to secede, its just another case of a minority of loud people, the separatist, seem like a majority. \n\nThey have voted on the subject, I believe that they almost got a majority once. \n\nOn my phone so I'm sorry about the lack reliable sources.\n\nedit: [it was in 1995,] (_URL_0_) thanks /u/Dzugavili\n",
"Quebec is a French province, and was conquered by the British\n\nIn fact, it used to be pretty much all there was of Canada. When the U.S. gained independence from England, a lot of English-speaking people who supported the King moved up to Canada. So now Canada had a French part, and an English part.\n\nFor most of this time, the French part stayed poor. Most of the land was owned by a small number of families, and later, most of the industrial companies were owned by the English. \n\nDuring the 60s, Quebecers decided they wanted to do better, and so started pushing against the people they saw as having power. This included the Church, and the English company owners. The movement was called the 'Quiet Revolution,' as it was led by trade unions and intellectuals who were inspired by socialism. \n\nAs part of that movement, some of those people thought the best way to take back that power is to separate from Canada, and be done with the English altogether. \n\nSince then, the Parti Quebecois has acted as a political party who's goal is to separate Quebec from Canada. The issue has been quiet for the past 20 years, but it's come back recently for two reasons. First, the PQ is in power, and looks set to win the next election. Second, Scotland is set to vote on independence from the United Kingdom. \n\nIt's important to note here that the idea of separation only has solid support from about 30% of the population there, so most people either disagree with it or aren't too sure. \n\nThere have been attempts to change the constitution of Canada to benefit Quebec, but there's very little faith in that process now because it has failed so many times in the past. \n\nBut that's a story for another time. Someday I'll tell you the story of Pierre Trudeau and the 'Night of the Long Knives.'",
"If this happens Im moving to ontario , fuck that. Seriously I just dont get it! why cant we just focus on being united instead of divided. Im from Quebec and I dont get why people's jimmies are rustled about people speaking english and such... Why is that a big deal?! Im from Quebec , but im still a proud Canadian.\n\ngod damn eh.",
"Their separatist schtick affects not only Canada. If you're an American businessman, who wants to market his product in Canada, and there's even a chance it will appear on a shelf in the province of Quebec, you are required to endure the additional expense of making your packaging (and instructional material) multilingual, to appease the Francophiles.",
"You have also to consider the fundamental differences in culture and beliefs between Québec and the rest of Canada. In the last federal election there were barely any votes for the Conservative Party at all across all of Québec. Yet the conservative gov owns a majority and have been destroying Canada has we know it turning it slowly into a replica of Bush era USA. For most 'muricans and Canadians this sounds great, but the majority of peoples in Québec don’t agree and feel like separation is the only thing that would let them have a say in their future.\n\nThis is because the conservative party knows no one will vote for them in Qc so they dont give a bulls arse what we think about tearing down Environment Canada, funding tar sands and hiding/destroying scientific evidence. So they go ahead and do whatever they want and know that they can still be elected with not one single vote in Qc.\nTHIS is not a democracy, when you know that your vote won’t have an impact, you either become cynical or a separatist IMO.\n\nEDIT : Also, some of the comments in this thread... wow. \"Let the frenchies leave and good riddance!\" \"they will all go bankrupt\" or the good old \"We'll invade the bastards, 'MURICA err I mean KANADA\" all make me want to leave this close minded country behind even more. You guys can't fathom that it would change next to nothing in your lives and has nothing to do with you? Unless you're scarred that loosing Qc would hurt Canada too much economically, wich doesnt make sense if your other argument is that Qc would go bankrupt without Canada."
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9mthhs | how is that earth has an atmosphere? what is fighting with the vacuum? why is some gas able to create pressure out of nothing? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9mthhs/eli5_how_is_that_earth_has_an_atmosphere_what_is/ | {
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"In a word, Gravity\n\nThe Earth's gravity pulls on the atmosphere the same way that it keeps the oceans glued to the earth.\n\nAt some point during the Earth's formation much of the Earth was liquid due to it's high temperature so the lighter gaseous elements like Hydrogen, Helium, Carbon Dioxide, and Nitrogen bubbled to the surface.\n\nMuch of this gas was lost to space but what remained formed our atmosphere.\n\nGravity is also what makes the atmosphere denser as you get closer to Earth's surface.",
"Gravity is keeping our atmosphere in place. How is gas able to create pressure out of nothing? It doesn’t ",
"Our atmosphere doesn't fly into space for the same reason YOU don't fly into space (not without going really fast and missing the ground): gravity. The mass of the earth pulls on the molecules of the atmosphere in just the same way it pulls on you.\n\nAll of the mass on or around the planet is gravitationally pulling on itself. If compression wasn't a thing all of the earth's mass would scrunch together into a small ball. But luckily, there's only so much the dirt, rocks, water can compress towards that center. Remember when you were a kid you'd all stack on top of one another? the kid at the bottom would be squashed, the kid on top would be unscathed. Same thing with the water in the ocean and the air in the atmosphere. If you're at the bottom of the ocean all of the water above you is squashing you as it wants to get closer to the center of the earth - hence why only very strong metal vessels can go that deep. Fortunately the air in the atmosphere is much less dense.. but even so the air pressure we experience at ground level is the result of all the air above us squashing us as it too is being pulled gravitationally towards the center of the earth. "
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99gtro | why multiple processors vs one larger processor | So these days the new generations of both CPUs and GPUs are integrating more cores/processor cores. So Why is this a better approach vs having one or just a few larger cores if multi-tasking is the concern?
In my uneducated opinion, each more core introduces more over heads; and typically the more cores there are, the more difficult it is to raise the clock speed.
If it's a thermal issue, the transistors can just be laid out in a larger foot print;
If it's for scalability, one larger processor can still take more tasks and let different parts of itself process them if its engineering this way.
Is this more a marketing scheme? Because I bet for 95% of the consumer market, 4 highly clocked cores are enough. But both AMD and Intel are pushing more cores to the main stream market. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/99gtro/eli5_why_multiple_processors_vs_one_larger/ | {
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"There are practical limits to single core performance: AMD and Intel both have famous examples where they focused purely on clock speed and failed miserably. \n\nThe thermal issue is more or less removing hest from the package, not from individual cores. The thermal interface of the processor package is pretty efficient.\n\nSome workloads are highly capable of using multiple cores. Also, spreading out the CPU package limits clock speed due to the distance between components.",
"Processors are basically made out of silicon which is a ~~high conductive metal~~ [semiconductor](_URL_1_) [metaloid](_URL_0_) and as any other material, it has some physical limitations.\n\nImagine a rubber band holding a deck of cards. You can continue including more and more cards inside but there is only so much stress you can put on the rubber band before it becomes loose or breaks.\n\nAlthough a loose rubber band still works it doesn't do the job properly. \n\nThe rubber band stress comes in a way of stretching, for the metal on the processor that stress is heat.\n\nThe faster a core is, more hot it will become, as it heats up it will loose efficiency (the equivalent of the rubber band becoming loose). And at some point it becomes really impractical to keep that core cool.\n\nSo, it is way more efficient, practical and cheap to have two 3ghz cores than a single 5 or 6ghz one.\n\n**Edit:** Concept correction about silicon being a high conductive metal as /u/Qwerty_Resident pointed out.",
"In the 80-90s most of the cpu performance increase was due to making progressively smaller transistors packed closer together so signals took less time to get around, which let you make the frequency higher. Now we are at a point where making transistors any smaller makes them stop working as transistors. Now, to to make a modern cpu have more performance in the same package, you can either add more cores (complete almost independent computing units that can each do almost anything on their own), letting it do more things in parallel (favorite tactic of AMD) or make each core more \"intelligent\" (able to predict what data it will need next so it can preload things to minimize wait times, have dedicated parts that can do complex operation in one clock cycle instead of 3, etc.)\n\n > one larger processor can still take more tasks and let different parts of itself process them if its engineering this way.\n\nThe parts that do this are literally cores.\n\n > In my uneducated opinion, each more core introduces more over heads; and typically the more cores there are, the more difficult it is to raise the clock speed.\n\nThat arhitecture overhead is not the problem. The problem is temperature. If you increase freequency (speed), you produce more heat. If you add more cores, you also add heat, but a bit more distributed.\n\n > If it's a thermal issue, the transistors can just be laid out in a larger foot print\n\nSignals can only travel so fast without getting corrupted by interference. If you want a larger footprint, you will need to lower the frequency, or your signals inside the processor will become mainly noise.\n\n > Because I bet for 95% of the consumer market, 4 highly clocked cores are enough.\n\nCan't have 4 *highly* clocked cores on a single chip right now. They will melt without some fairly expensive cooling. Making and cooling 8 lower clocked ones is cheaper, as making them costs the same as making 4 cores.\n\nAlso, programmers have gotten lazier (due to time pressures) and aren't writing efficient code like they did in the era of early computing. Plus the programs are getting more and more complicated and resource hungry, just look at windows. This means that you need to keep increasing the performance of the hardware to maintain the same level of user experience.\n\nEdit: formatting\nEdit2: slower code."
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kvakk | why do women get so bad-tempered and difficult before they menstruate? | I can usually tell when my wife is going to have her period because her whole sweet nature changes and then I know it's time to go work in the garden and any other duties just to keep out of her way.
The mere fact that I'm even alive seems to irritate her at this time. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/kvakk/eli5_why_do_women_get_so_badtempered_and/ | {
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"I'm a woman and I am mystified by it. I don't think I am any different from one week to the next. ",
" > I can usually tell when my wife is going to have her period because her whole sweet nature changes \n\nI can tell my wife is because she tells me, and i know its every 4 weeks. I still dont get why spouses dont communicate about this stuff.",
"Hormone fluctuations can affect your mood in crazy ways. \n\nThe other day I was sitting on the couch and was suddenly mad at my husband for no reason whatsoever. That is when I decided to go into another room and fold laundry. I knew if I kept sitting there, I would say something I'd regret.\n\nHubby and I have a unspoken code to cue him in. I remove my nail polish for those days.",
"There actually isn't solid proof what specifically causes PMS as there are so many different symptoms between women. The general consensus is that different levels of sex hormones mess with the chemicals in the brain, which can cause mood swings. \n\nAnd not every women gets bad-tempered as the symptoms do differentiate from each individual. ",
"It's hormones. However, I think its a misconception that women only get bad-tempered when they are pre-menstrual. Sometimes I notice I get irritated and angry for no reason, but more often than not I just find myself over emotional at everthing.\n\nCase in point: I cried yesterday because I was stuck in traffic, that made me 15 minutes later to the gym that I wanted to be - even though I was going alone, so it didn't matter when I got there. I've also been known to cry at On-star radio ads, and Tim Hortons TV commercials. ",
"None of these comments are addressing the question appropriately. You can't just say \"bc hormones\" or \"bc fuck you that's why\" to a five year old. And even if the concept of whether irritability and other PMS symptoms are attributable to hormones is controversial or not, ELI5 should look to present general and prevalent hypotheses in a better manner. I can't because I don't have the background, but it isn't helping for people to either be arguing that hormones don't or do have anything to do with irritability without getting into details of why or why not. ",
"I think there are several things. \n\nThe biggest one for me, is I am just all around pissed that I am on my period. For instance, having to work sucks, but having to work when I have cramps is just the worst ever, and that alone pisses me off. \n\nBeing in constant pain puts me in a horrible mood. Not being able to fit into my pants depresses me and pisses me off. I am hungry more, and yet the only thing that satisfies are things like chocolate, ice cream and donuts, and since I am already fat and can't fit into my pants, I can't eat these things, which pisses me off, or I do eat those things, which pisses me off.\n\nI hate to get gross on you, especially since you are 5 and all, but a lot of women get diarrhea and have to pee a lot more often. And trust me, bleeding out your vag for several days on end sucks. I feel all around just...dirty. Most men wouldn't touch us with a 10 foot pole, and a lot of men will touch us enough to tease us then politely request a BJ (sorry if you are 5, I am not explaining what that is). Since we have raging hormones, there is a chance we actually WANT to 'do it,' but can't because it is disgusting. This pisses me off.\n\nThen there is the whole chemical imbalance. We are losing blood, so we have a drop in blood sugar which dramatically affects the mood. Our hormones change, also affecting our mood. We lose blood, and this causes a drop in iron, causing fatigue and irritability. Knowing that this is happening to me, making me mad or sad for no reason, pisses me off.\n\nIt is as if you got food poisoning once a month. Every month you know it is coming. You know you are going to be in pain, in the bathroom, and there is really nothing to help or stop it. You are just told to live with it until you are around 60 and then it gets worse before it gets better. On top of hating that, your body also releases hormones that make you even more angry/depressed when it comes. It just sucks.\n\nEDIT: These are all worst case scenarious, just like food poisoning, some months you are OK with it and it is not THAT bad, other months you really are in no mood to start vomiting for the next 5 days. ",
"Do you ever get irrationally cranky when you're very hungry or very tired, and not realize that you're acting differently from normal until you feel better? That's kind of what it's like--in addition to a flood of hormones you can't control, there are body aches, cramps, and fatigue that makes everything you try to do a little more difficult. ",
"For me, it's the pain. PCOS :(\n\nEdit: the vicodin helps ease the bitchiness.",
"Their body is really freaking angry that it used all of that effort to take care of that egg and now it has to tear everything back down and start again.",
"I don't know but it makes you want to scream one minute and burst into tears the next. It's possible to control (I don't go around sobbing the entire time of course) but having to deal with those extreme impulses definitely makes one crabby.",
"Imagine that your dick bleeds profusely and is in terrible pain once a month for several days.",
"If you knew you were about to bleed for 5 days straight, you'd be in a bad mood, too.",
"Ok watchitman, I'm gonna try and explain in terms of science. Reposted from my reply below. \n I'm no expert but I do know that nobody knows the definitive cause of PMS. There probably isn't one thing that causes it, as every woman is different, etc. But if any of you know someone who is menopausal (i.e. they are past reproductive age and their periods are stopping) it might give a bit of insight. During the last week of a fertile woman's cycle, levels of the hormone estrogen decline. This also happens during the menopause (anyone else have a crazy menopausal mother if she doesn't take her hormone replacement pills?).\nEstrogen's responsible for a lot of things in the female body, and it's absence basically alters the woman's entire body chemistry. In particular it affects neurotransmitters such as serotonin and GABA. Serotonin is the \"happy\" hormone, and GABA is responsible for a general feeling of stability or calm. So when these fluctuate it's thought to cause mood swings. Additionally, declining estrogen and increasing progesterone during a period decrease levels of endorphins. Endorphins are the body's natural painkillers and also give you an energised feeling. So less endorphins = more pain. To offset the pain and mood swings, it is actually recommended to exercise or have sex - both of these release endorphins into the body and sex (good, orgasm-achieving sex) causes a release of serotonin. Also the sex is supposed to be better than usual as your entire vagina is more sensitive to pleasure as well as pain.\nSo that should make you feel better, but obviously due to the other symptoms so accurately listed by sexlexia - bloating, etc - you don't often feel like jumping your partner's bones. \n",
"A note to the girls - you crave more carbs, and generally sugary bad foods because they help your body produce serotonin. It's just your body recognising that it needs to make more happy hormone, ladies - go with it, but don't go too mad. At the end of the week the water retention and bloating should be gone, then you can fit into your jeans again ;)",
"Women in sports: If you have a game scheduled during that time, how do you cope with it?",
"The simplest way i understand it is basically withdrawals. Just like a drug user or alcoholic coming off women have the same reaction to producing less hormones in their body. ",
"I once had a boyfriend who was convinced all women fake PMS as an excuse to bitch out randomly.. ugh.",
"Ladies, suppose you're experiencing PMS. As a guy friend or a boyfriend, what's the best thing(s) for us to do to help you or show support?",
" > Why do women get so bad-tempered and difficult before they menstruate? \n\n**BECAUSE THAT'S WHEN YOU SUCK, OK??!!** ",
"My last girlfriend was the best at handling PMS. I had to rely on communication to know when her period was coming because her personality didn't change, AT ALL. \n\nBest of all, she was still sexually active during the period (just wear a condom and clean up afterwords, it's no big deal) and after it was over, for the next few days her horniness levels went through the roof.\n\nThrough my experience, she seems actually kinda like a normal girl. Either that, or I just lucked out, I guess.",
"Hormones. Happens with men too (not triggered by menstruating, of course). But hormones, and chemical balances, causes everyone to get fired up.",
"from what I've heard periods are like getting tapped in the balls. For days. Any man who has had this happen to him knows what that's like.",
"There is some speculation that it may help prevent tubal pregnancies in primitive societies, which can easily be fatal to both the mother and child.\n\nAs a side-note, sex as soon as you sense ovulation after a two week abstinance (or using condoms) will have a much higher incidence of boys being born (maybe from more of the tribes men dying in battle, and the remaining men have several wives?)\n\nIf you have frequent unprotected sex, the result is more female babies (perhaps when the women of the tribe have a husband and a boyfriend too?)\n\nThese are because boy sperms swim faster, but die sooner. Sounds like a joke, but regardless of what the actual reason may be, its true.",
"I'm a woman and I am mystified by it. I don't think I am any different from one week to the next. ",
" > I can usually tell when my wife is going to have her period because her whole sweet nature changes \n\nI can tell my wife is because she tells me, and i know its every 4 weeks. I still dont get why spouses dont communicate about this stuff.",
"Hormone fluctuations can affect your mood in crazy ways. \n\nThe other day I was sitting on the couch and was suddenly mad at my husband for no reason whatsoever. That is when I decided to go into another room and fold laundry. I knew if I kept sitting there, I would say something I'd regret.\n\nHubby and I have a unspoken code to cue him in. I remove my nail polish for those days.",
"There actually isn't solid proof what specifically causes PMS as there are so many different symptoms between women. The general consensus is that different levels of sex hormones mess with the chemicals in the brain, which can cause mood swings. \n\nAnd not every women gets bad-tempered as the symptoms do differentiate from each individual. ",
"It's hormones. However, I think its a misconception that women only get bad-tempered when they are pre-menstrual. Sometimes I notice I get irritated and angry for no reason, but more often than not I just find myself over emotional at everthing.\n\nCase in point: I cried yesterday because I was stuck in traffic, that made me 15 minutes later to the gym that I wanted to be - even though I was going alone, so it didn't matter when I got there. I've also been known to cry at On-star radio ads, and Tim Hortons TV commercials. ",
"None of these comments are addressing the question appropriately. You can't just say \"bc hormones\" or \"bc fuck you that's why\" to a five year old. And even if the concept of whether irritability and other PMS symptoms are attributable to hormones is controversial or not, ELI5 should look to present general and prevalent hypotheses in a better manner. I can't because I don't have the background, but it isn't helping for people to either be arguing that hormones don't or do have anything to do with irritability without getting into details of why or why not. ",
"I think there are several things. \n\nThe biggest one for me, is I am just all around pissed that I am on my period. For instance, having to work sucks, but having to work when I have cramps is just the worst ever, and that alone pisses me off. \n\nBeing in constant pain puts me in a horrible mood. Not being able to fit into my pants depresses me and pisses me off. I am hungry more, and yet the only thing that satisfies are things like chocolate, ice cream and donuts, and since I am already fat and can't fit into my pants, I can't eat these things, which pisses me off, or I do eat those things, which pisses me off.\n\nI hate to get gross on you, especially since you are 5 and all, but a lot of women get diarrhea and have to pee a lot more often. And trust me, bleeding out your vag for several days on end sucks. I feel all around just...dirty. Most men wouldn't touch us with a 10 foot pole, and a lot of men will touch us enough to tease us then politely request a BJ (sorry if you are 5, I am not explaining what that is). Since we have raging hormones, there is a chance we actually WANT to 'do it,' but can't because it is disgusting. This pisses me off.\n\nThen there is the whole chemical imbalance. We are losing blood, so we have a drop in blood sugar which dramatically affects the mood. Our hormones change, also affecting our mood. We lose blood, and this causes a drop in iron, causing fatigue and irritability. Knowing that this is happening to me, making me mad or sad for no reason, pisses me off.\n\nIt is as if you got food poisoning once a month. Every month you know it is coming. You know you are going to be in pain, in the bathroom, and there is really nothing to help or stop it. You are just told to live with it until you are around 60 and then it gets worse before it gets better. On top of hating that, your body also releases hormones that make you even more angry/depressed when it comes. It just sucks.\n\nEDIT: These are all worst case scenarious, just like food poisoning, some months you are OK with it and it is not THAT bad, other months you really are in no mood to start vomiting for the next 5 days. ",
"Do you ever get irrationally cranky when you're very hungry or very tired, and not realize that you're acting differently from normal until you feel better? That's kind of what it's like--in addition to a flood of hormones you can't control, there are body aches, cramps, and fatigue that makes everything you try to do a little more difficult. ",
"For me, it's the pain. PCOS :(\n\nEdit: the vicodin helps ease the bitchiness.",
"Their body is really freaking angry that it used all of that effort to take care of that egg and now it has to tear everything back down and start again.",
"I don't know but it makes you want to scream one minute and burst into tears the next. It's possible to control (I don't go around sobbing the entire time of course) but having to deal with those extreme impulses definitely makes one crabby.",
"Imagine that your dick bleeds profusely and is in terrible pain once a month for several days.",
"If you knew you were about to bleed for 5 days straight, you'd be in a bad mood, too.",
"Ok watchitman, I'm gonna try and explain in terms of science. Reposted from my reply below. \n I'm no expert but I do know that nobody knows the definitive cause of PMS. There probably isn't one thing that causes it, as every woman is different, etc. But if any of you know someone who is menopausal (i.e. they are past reproductive age and their periods are stopping) it might give a bit of insight. During the last week of a fertile woman's cycle, levels of the hormone estrogen decline. This also happens during the menopause (anyone else have a crazy menopausal mother if she doesn't take her hormone replacement pills?).\nEstrogen's responsible for a lot of things in the female body, and it's absence basically alters the woman's entire body chemistry. In particular it affects neurotransmitters such as serotonin and GABA. Serotonin is the \"happy\" hormone, and GABA is responsible for a general feeling of stability or calm. So when these fluctuate it's thought to cause mood swings. Additionally, declining estrogen and increasing progesterone during a period decrease levels of endorphins. Endorphins are the body's natural painkillers and also give you an energised feeling. So less endorphins = more pain. To offset the pain and mood swings, it is actually recommended to exercise or have sex - both of these release endorphins into the body and sex (good, orgasm-achieving sex) causes a release of serotonin. Also the sex is supposed to be better than usual as your entire vagina is more sensitive to pleasure as well as pain.\nSo that should make you feel better, but obviously due to the other symptoms so accurately listed by sexlexia - bloating, etc - you don't often feel like jumping your partner's bones. \n",
"A note to the girls - you crave more carbs, and generally sugary bad foods because they help your body produce serotonin. It's just your body recognising that it needs to make more happy hormone, ladies - go with it, but don't go too mad. At the end of the week the water retention and bloating should be gone, then you can fit into your jeans again ;)",
"Women in sports: If you have a game scheduled during that time, how do you cope with it?",
"The simplest way i understand it is basically withdrawals. Just like a drug user or alcoholic coming off women have the same reaction to producing less hormones in their body. ",
"I once had a boyfriend who was convinced all women fake PMS as an excuse to bitch out randomly.. ugh.",
"Ladies, suppose you're experiencing PMS. As a guy friend or a boyfriend, what's the best thing(s) for us to do to help you or show support?",
" > Why do women get so bad-tempered and difficult before they menstruate? \n\n**BECAUSE THAT'S WHEN YOU SUCK, OK??!!** ",
"My last girlfriend was the best at handling PMS. I had to rely on communication to know when her period was coming because her personality didn't change, AT ALL. \n\nBest of all, she was still sexually active during the period (just wear a condom and clean up afterwords, it's no big deal) and after it was over, for the next few days her horniness levels went through the roof.\n\nThrough my experience, she seems actually kinda like a normal girl. Either that, or I just lucked out, I guess.",
"Hormones. Happens with men too (not triggered by menstruating, of course). But hormones, and chemical balances, causes everyone to get fired up.",
"from what I've heard periods are like getting tapped in the balls. For days. Any man who has had this happen to him knows what that's like.",
"There is some speculation that it may help prevent tubal pregnancies in primitive societies, which can easily be fatal to both the mother and child.\n\nAs a side-note, sex as soon as you sense ovulation after a two week abstinance (or using condoms) will have a much higher incidence of boys being born (maybe from more of the tribes men dying in battle, and the remaining men have several wives?)\n\nIf you have frequent unprotected sex, the result is more female babies (perhaps when the women of the tribe have a husband and a boyfriend too?)\n\nThese are because boy sperms swim faster, but die sooner. Sounds like a joke, but regardless of what the actual reason may be, its true."
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2aweg3 | if land slowly erodes over time due to water, will we eventually run out of land? | I was at Niagara Falls the other day and was shown where the falls used to be, and it moved due to erosion.
That is, if we don't destroy the planet before that happens. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2aweg3/eli5_if_land_slowly_erodes_over_time_due_to_water/ | {
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"if the plates stopped moving, and the earths interior stopped moving (bigger problems, but I digress), you would eventually get a planet smoothed out like the ocean floor - so yes, we would run out of *dry* land. \n\nEDIT - added 'dry'",
"No, when we speak of erosion, it is not that all land is eroding away. It is the rock and hard land that is eroding.\n\nThat means that the water is breaking it down into smaller parts and the water carries it away. The land is being moved, but never goes away. Once it goes to the bottom of the ocean its as good as gone though.\n\nThe only reason all the land doesn't eventually end up in the bottom of the ocean is because our tectonic plates push together and one gets pushed above the other creating higher land and mountain ranges. This is a billion year battle between rock and water that will never end. Our Earth will continue to reshape itself, but we will always have ground to stand on, at least for our lifetime.",
"Nah, ocean currents will pull silt and either let it go the the bottom of the ocean or deposit the silt elsewhere. Also, plate tectonics creates new land all the time by either colliding to create mountains or separating to create trenches. Finally, active volcanoes create land too."
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2ls120 | how does a heatsink work? | i know that they dissipate heat, but i dont quite understand how. on my RAM in my computer, there are these little slots in the top and im not quite sure how they dissipate heat. (_URL_0_ Pic of the ram) also, do sme heatsinks work diffrently than others? thanks for your help! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ls120/eli5_how_does_a_heatsink_work/ | {
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"Heat sinks have three important characteristics. One, they are made a material with a high thermal conductivity, they transport heat really fast. The heat can get from the surface where it contacts what it is trying to cool to the ends of the fins really quick. This means they are metal, usually aluminum, as metals conduct heat very well. Two, they have a large surface area. This is why they have these fins, they expose the heat sink to as much air as possible to offload the heat to. Lastly, they have to make good thermal contact with whatever they are trying to cool. This is using done with a highly conductive paste or epoxy. Sometime, but not always they also have a fan aimed at the fins. This increases the heat dissipation even more. Brining colder air to replace the already warmer heated air allows heat to be transferred quicker. \r\r\rThey also find a lot of uses besides just computers. For example, transformers in the power grid have massive heat sinks with several larger fans. "
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cb00h2 | in cricket, why do the bowlers run-up before actually bowling? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cb00h2/eli5_in_cricket_why_do_the_bowlers_runup_before/ | {
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"In a nutshell it has to do with effort, momentum, stamina and accuracy. \n\nThe batsman at international level have brilliant reactions and eyes for the ball, meaning if you bowling the ball at 100km/ph with no movement then they are going to find it very easy to hit you for boundaries.\n\nSo now you have two choices. You could start applying spin on he ball, which is easier if the ball is traveling slower because it can move more. Or you could increase the speed at which you bowl in order to make it more difficult for the batsmen. \n\nAs an example, stand 10m away from a wall and bowl at the wall with no run up. Listen to the sound it makes when it hit the wall or just see how fast it is. Then take a 10m run up and then bowl against the wall. Note how you’ve bowled it much faster. You can even do the same action with a run up and less effort, it will still likely go faster than with no run up.\n\nBasically, a longer run up means you can bowl faster. However you don’t want it to be too long because then you will be wasting unnecessary energy. This is where stamina comes in. \n\nCricket can at times be a long sport. In a 50 over game a bowler is allowed to bowl 10 overs, with each over 6 balls. That means a bowler can bowl at 60 balls in a game, or even more should he bowl no balls, wides. Imagine the success rate of a bowler who bowls all of those deliveries at the same slow speed with no variation. But increasing the speed at which you bowl or the variation, your success rate becomes much higher. \n\nHope this helps, feel free to ask more questions :)"
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5ex5yn | why do most inventions have weird numbers behind its name like "5000" ? | When did this trend start? Does it actually mean something? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5ex5yn/eli5_why_do_most_inventions_have_weird_numbers/ | {
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"Are you talking about \"EZwrap 3000\" type names? It's just random marketing.\n\nBut In markets where technology actually leads to constant product refreshes the numbers generally correspond to the year make and model of the product. Example would be Intel Core i5-4630, where the 4630 actually means quite a bit. "
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ag0ot3 | why can’t sound engineers create a consistent volume level throughout an entire movie or tv show, it’s either too quiet or way too fucking loud at different times? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ag0ot3/eli5_why_cant_sound_engineers_create_a_consistent/ | {
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"They can, it is just bad. \n\nPart of what makes a show or movie better is to have dynamic range in the sound. It makes things more like real life and most of the population enjoys the movie more. ",
"1) They mix for a listening environment that you probably aren't experiencing.\n\n2) They mix to intentionally have intimate moments and dynamic moments for the sake of immersion in the show/movie\n\n3) Converting from a sound mix made for a giant theater with 30 speakers down to a 2-speaker presentation, or even a 5.1 presentation takes a lot of work that has to deal with issue 1.",
"I get it for people who have a home theatre/surround sound. But watching on a regular TV, I constantly have to blast up the volume of a show just to hear dialogue, then crank it way down every time there's a loud sound effect or music playing so it doesn't piss of neighbors. I live in an apartment building and tend to watch stuff later at night so it's quite a pain.",
"Imo a better question would be why isn't there a separate track for SFX and dialogue so you could adjust both independently like many video games let you do.",
"Seriously. Theme music is way too loud. It may be mixed perfectly to a million dollar sound system but if it cant be played on 2 speakers, its still a bad mix. "
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9i20gz | why are coffins shaped the way that they are? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9i20gz/eli5_why_are_coffins_shaped_the_way_that_they_are/ | {
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"US coffins/caskets seem to be a regular box shape. UK ones are narrower at the feet, wider at the shoulder and narrower again at the head. It is the shape of a body. So I assume that is why U.K. ones are that shape.\n\nWe are getting organic/environmentally friendly ones now that are mostly made of wicker and these are more shaped like a old fashioned Moses basket. I assume as they are easier to make this shape.",
"It's because it became traditional for arms to be crossed. So the oblong had to become an oblait hexagon.\n\nIt's worth pointing out that nowadays they are just oblongs, so the cartoon style ones are like floppy disk icons.\n\nDon't exist, but remain shorthand.",
"I second the arm crossing thing. I’ve always thought African caskets were awesome, not sure if it’s super specific to a particular country or region though. They’re typically shaped as something that was related to the persons hobbies or occupation. Carpenter = hammer, farmer = chicken, chef = cooking pot. \n\nEdit: Found it! They’re called fantasy coffins, pretty big in Ghana. "
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n0rtu | why reflective things (like aluminum or 3musketeers candy wrapper) explode in the microwave. | I stupidly tried to thaw a 3 Musketeers bar when I was little... Thought about it today and wondered why. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/n0rtu/eli5_why_reflective_things_like_aluminum_or/ | {
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"It isn't because it's reflective, but rather because it's metal. Metal things conduct electricity. One effect of the microwave is to make electricity flow in anything conductive inside of it. That electricity creates sparks and plasma (a lot like lightning, but on a smaller scale), making things heat up, catch fire, or explode.",
"It isn't because it's reflective, but rather because it's metal. Metal things conduct electricity. One effect of the microwave is to make electricity flow in anything conductive inside of it. That electricity creates sparks and plasma (a lot like lightning, but on a smaller scale), making things heat up, catch fire, or explode."
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20mozv | before modern consoles, why didn't older games have bugs like newer games that get updates constantly with patches? | Although older games did have bugs, it doesnt seem as buggy as newer games. Were older games more well written? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/20mozv/eli5_before_modern_consoles_why_didnt_older_games/ | {
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"Less information on them, less to screw up.",
"Older games were much simpler, so it was far easier to make them without having as many bugs.\n\nAlso there really was zero option to update games reliably with patches in the past, now it's automatic since everyone is almost always connected to the internet.\n\n\"more well written\" is incredibly difficult to answer, since we almost never have an actual idea about the code that actually made up the game.",
"Two main factors: older games were simpler and (before Internet-connected consoles) there was no easy way to fix a broken game after shipping. \n\nA great example is Turok Rage Wars on N64. There was a bug that caused some players to not be able to finish the game. The developer had to fix the bug and ship a free cart to anyone who wrote in complaining of the bug. The cost of time spent fixing the bug, manufacture of new carts, shipping and potential lost sales due to the game's buggy reputation must have been huge.",
"In addition to all the comments below(or above) about complexity and user bases. \nAs a development company, you used to be able to take your time to market. invest heavily in a detailed requirements of the game. spends a lot of time documenting and testing the game. If we are talking before internet. as long as you could play through the game in a happy path (meaning the game worked if you walked through it). and no major crashes or bugs were found during exploratory testing. you had a pretty good chance it wouldn't come back to haunt you after release Imagine writing a snail mail letter to complain about a bug, and even then it would probably be more beneficial to compensate the few who complained. \nIn today's market, you are pressured to release on a much tighter deadline, your time to document and test the game can be quite limited but the requirements for updates and new functionality grows. In addition you have many small shops that can use the crowd testing as a quicker, cheaper way to test the game.",
"Probably older games were made by smaller amount of people and it was easier to make different parts work together.\nThey were also more simple, but it already has been said.",
"Older games did have bugs. In fact, the very first Final Fantasy had quite a few bugs, most notably the Intelligence and Critical Hit bugs.",
"Older games were simpler. No online play to worry about patching updates to balance weapons and remove hacks.\n\nLess \"moving parts.\" There was also not as much OS, driver, and console patching to worry about.\n\nMoreover, there was no method to distribute updates. Now everyone has broadband and it seems to be SOP by developers to make a promised ship date and have a 100+ MB patch that needs to be downloaded to play at launch. If you tried to have a 100+ MB download in 1996, your game would bomb. For example: [Sin](_URL_0_). I remember having to download a 25MB patch on a 28.8 kbps modem and it taking four hours. ",
"yes, they were more carefully looked over precisely because they couldn't just patch it. EA in particular has become notorious for their \"ship broken crap, fix it later\" mentality.\n\nof course, that's not the only factor. games now contain much, much more code. an NES game had a max size of 6 megabits. a modern game contains tens of thousands times more data. just on pure size it's impossible for anything other than the general population to *completely* test a game\n\nthere is so much data in game creation that much of it is not original code, but instead bundles of pre-made packages. physics engines, shaders, etc. all made by different companies. where these codes come in contact, crap tends to happen.",
"Dude older games had a ton of bugs, most people may have forgotten about them, but Poke'mon Gen 1, for instance, had more bugs than you could shake a stick at, BECAUSE of the simple coding system. Same with LoZ:OoT.\n\nVenusaur was a pokemon slaying bug machine. You could bug out trainers and catch a mew, etc, etc. A lot of these just had to do with the system they used to code (Pokemon design number) and just bad code design, such as rolling over numbers (99-- > -01 or vice versa), or using the same number count for multiple abilities (leech seed & toxic stacking).",
"There are not more bugs just more publicity pointing them out. ",
"Watch some older games on speedrunslive and tell me older games don't have bugs, lol.\n\nSome games are incredibly broken. There's a bug in Ocarina of Time that warps you to the last battle with Ganondorf thus allowing you to \"beat\" the game in about 20 minutes.\n\nPeople saying that older games didn't have bugs because they're \"Simpler\" are completely wrong. They had bugs. Tons of them."
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488ajh | why does water taste sweet and generally better after running? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/488ajh/eli5_why_does_water_taste_sweet_and_generally/ | {
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"Your body is dehydrated. Evolution has made it such that fulfilling a need is immensely satisfying. So your brain has been programmed to find water much more satisfying if you are thirsty."
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aip80f | why the passenger seat in a car is called shotgun? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/aip80f/eli5_why_the_passenger_seat_in_a_car_is_called/ | {
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"It's related to travel by coach (pulled by horses). The driver is controlling the horses. The person next to them is holding a shotgun to protect the coach from robbers.",
"Someone told me once it was because back in the day stagecoaches and stuff always had a guy with a shotgun sitting there.",
"I think back when there was horse drawn buggies the passanger next to the person holding the ranes of the horse had a shotgun called a coach gun as a means of defense. So the seat next to the driver is the shot gun seat \n\n",
"(slang) The front passenger seat in a vehicle, next to the driver; so called because the position of the shotgun-armed guard on a horse-drawn stage-coach, wagon train, or gold transport was next to the driver on a forward-mounted bench seat.I call shotgun! (I claim the right to sit in the passenger seat",
"In the days when horses were the means of travel in the American West, a horse drawn stagecoach (4 to 6 to sometimes 8 horses called \"a team\") would often employ an armed guard if the stage was going through rough or dangerous territory. As the western territory was often wide open with little shrubbery or places to hide and ambush, plus the lack of seats on the top back of the stagecoach, the guard's best vantage point was next to the driver, and the best gun for that wide open territory was a rifle or shotgun. There was room for only one other person besides the driver on the front seat, so the term \"sitting shotgun\" was give to anyone (preferably armed with a rifle who knew how to use it for defense) seated next to a stagecoach driver.\n\nFor an American East Coast public coach (put to 4 horses, and called a \"four in hand\" when the coach was private) or an European coach, the seat next to the driver (who is properly called a \"coachman\") was often filled by a passenger who might wish to try driving the horses himself. The guard didn't sit there. The guard sat on the bench at the top rear of the coach. While armed, he also had a second job which was being the \"coachhorn\" or \"tootler\" - someone who blew the coaching horn to announce arrivals, departures, passing, and other horn tunes to identify the particular coach, speed, or greet another coach. The reason the guard sat in back was to have a full range of view of all sides of the coach, as well as the road behind the coach, because coaching routes in the eastern Americas and Europe often traveled through dense woods, shaded lanes, and other closed in roads where highwaymen (bad guys) could hide and jump out to grab the lead horses reins, or leap unseen from the trees after the coach has passed by and sneak on the back of the coach to climb up and attack the coachman behind his back. A guard on the back of the coach would quickly discourage a thief from trying to attack from the rear. A short pistol was the defensive weapon of choice as it was easy to handle, easy to load, very accurate at short range, and could be tucked into the guard's coat when he was busy blowing the coach horn. Also shooting a pistol directly over the heads of the horses wasn't the safest, but shooting a pistol from the back of the coach was less stressful to the horses.\n\nSo \"riding shotgun\" is purely an old American West stagecoach term that is now used for anyone riding in the front passenger seat of a car.\n\n",
"Sadly, from the little digging I've done into States I routinely travel it, it's illegal for a person \"riding shotgun\" to actually be carrying a loaded shotgun.\n\nI drive a lot, so next time I was with friends going somewhere and someone called shotgun I was going to pull an actual shotgun out of the trunk for them to carry. Alas, that would be illegal.",
"It refers to the concept of armed man riding next to the driver of a stagecoach.\n\nFun fact, this term is actually originated in cowboy movies in the 60's. Not the actual old west."
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2c1rep | why cannot signatures be forged/copied perfectly, with sufficient resolution and the right ink? | Surely anything to do with strokes could be imaged if you zoomed in enough, and then perfectly replicated with a precise enough ink jet printer? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2c1rep/eli5_why_cannot_signatures_be_forgedcopied/ | {
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"People are missing the point. Yes you can *easily* create an exact digital copy of a signature. A decent scanner, simple cut and paste, and you can do it in seconds.\n\nThat is why legal documents must have original signatures on them (ink on paper).",
"It's possible to make a near perfect fake, but criminals are lazy and good enough is good enough for them. And most real signatures are done with cheap pens, so it makes more sense to fake one using a cheap pen. ",
"Original signatures are hard to replicate because it's not just how the signature looks, it's also the fluidity in which it was signed. The number one thing that gives a forged signature away is hesitation while making the signature, which makes easy to see marking on the signature. Of course, there are some people who can train themselves with sufficient practice to replicate this signature. I just watched a film called F is for Fake by Orson Welles about an art forget named Elmyr who could do this with paintings. He even painted a Matisse painting and signed it with Orwell's signature, which Orwell himself said was an exact copy and indistinguishable from his own."
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2amnjr | why don't we all work together cooperatively and be a "big happy family"? | yes this is an incredibly naive and stupid question; but id like some responses; is it mostly down to the combination of the following 2 factors: 1. limited resources, 2. we can only experience our own qualia (for now) | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2amnjr/eli5_why_dont_we_all_work_together_cooperatively/ | {
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"Mostly because the things the other guys want aren't good ideas to you, so you'd rather have your ideas. If you think the other guys are deliberately trying to undermine you (and sometimes they are) it's even harder to be a \"big happy family\"",
"Find a definition of \"happy\" that we all agree with, and a means of achieving it and I'm sure we all can be.",
"That's funny, [I just watched a Youtube video about this topic earlier today.](_URL_0_)\n\nI think he explains it well using the metaphor of a forest, where trees would all be better off if they agreed to only grow to a certain height and share the sunlight, but as soon as one tree grows a little bit taller and starts taking more of the light, it's ruined for the whole forest and they must all start competing.",
"People don't like each other, some just flat out hate each other( I've met people where we try to get along but at the end we just hate each other)",
"The problem is the \"big\" and \"happy\" parts. Our family is very small and very lose with 6 of us total and not much extended family. We pretty much get along with everything except for one: food. Everybody has *very* different tastes and let me tell you: it doesn't matter how close you are, you couldn't be further apart when it comes to finding a place to eat or deciding on a certain recipe for dinner. Break us into smaller groups and we'll have more of a tendency to agree & accept things; but its when you're trying to get everybody to agree on one thing is where you'll have trouble.",
"In my experience: Everybody has conflicting interests. We all want different things for ourselves or our group. If we convince ourselves that our interest is the most important, the idea of being a \"big happy family\" goes out the window. ",
"Because fuck you, I got mine.",
"because I deserve more than you.\n\nmy kids need more than yours.\n\nthink i'm wrong? wont share? i'll kill you and take what you wont give me.\n\ni'm an animal who thinks i'm a god and knows you are an animal",
"I recently read an interesting book called \"On Aggression\" by Konrad Lorenz that deals with this subject. The basic idea is that natural selection is to blame. It's the result of competition for survival and mating opportunities. That whole mindset is still part of our biology even though we've been out of the jungle for quite a while now. We seem to be evolving away from it, although it's taking longer for some of us than others."
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7c4md5 | why does bread get tough when left outside a bag/box for some time, but crackers get soft in the same situation? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7c4md5/eli5_why_does_bread_get_tough_when_left_outside_a/ | {
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"Bread has a lot of moisture (google says 40%). So, leaving it out leads to the liquid evaporating out and drying out the bread. Crackers have very little moisture, that's why they can last much longer than bread. So, when you leave them out, they absorb the moisture from the surrounding environment. "
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673n6y | r/k selection theory as it pertains to modern humans. | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/673n6y/eli5_rk_selection_theory_as_it_pertains_to_modern/ | {
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"Oof, it's been a while since I last worked on r/K, so bear with me here.\n\nr-traits are traits that maximize the number of offspring one organism can produce at the cost of low probability that any individual offspring will survive. Dandelions are a good example of r species because they produce tons of seeds but don't nurture any of them (no hard shell, etc.).\n\nK-traits are traits that maximize the probability that any single offspring will survive at the cost of having few offspring. Humans are a good example of K species because humans tend to have few children and provide each with plentiful resources to grow.\n\nModern society has sometimes been criticized for making it too easy to have tons of children and leave the state to take care of them, so an individual parent can pursue an r strategy without lowering the likelihood that any of his/her offspring will die. This is perceived as unfair because when everyone else pursues the K strategy, they produce few offspring of their own and also have to bear all the costs of the r strategy parents.\n\n(OPINION: I personally advocate for government support on two children and no tax benefits for having more. I do not think it would be unfair for individuals to be required to register one child maximum per parent and for couples to be required to undergo operations to prevent them from having more children after two. If the parents got a divorce, each child would go to the parent that registered him/her. If you couldn't care for your child, you would still lose your one maximum and your child would go somewhere else. No bonuses for remarriages after divorce.)",
"r/K selection theory is outdated even in *non*humans, though several of its concepts have been incorporated into its successors. Furthermore, since it was always about comparisons *between species*, its primary relevance to modern humans is that we are a species that overall uses a K-selection strategy: we produce one offspring per pregnancy the *vast* majority of the time, and put a lot of resources into ensuring the comparatively low numbers of infants thereby produced reach maturity. This is in contrast to r-selecting species, like mice, which have lots of offspring and don't sink much into any given one, relying on producing enough to overcome the high resulting mortality rate.\n\nHuman K-selection has been getting all the more pronounced as technology improves and infant mortality declines, in a sense, but this is not a biological or evolutionary effect so much as a social one, so the applicability of r/K selection theory is shaky at best.\n\nSome people have tried to shoehorn human races into r/K theory, but that relies on unfounded generalisations about races that treats them almost as subspecies, and is essentially a form of racist pseudoscience. Pay it no heed, save maybe to mock it."
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1z53u8 | what is a 'primordial ooze," and how did the first single-celled organisms come from it? | I do not have any religion-based skepticism, I'm just not a scientist. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1z53u8/what_is_a_primordial_ooze_and_how_did_the_first/ | {
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"The primorial ooze consisted of carbon, nitrogen, oxygen, sulfur and phosphorus in water. Amino acids form in such a solution as do lipids. These are the building blocks of proteins and fats. Lipids tend to float on water rather than mix with water. The first cells formed when lipids collected in a ball and trapped RNA inside. We believe that RNA existed before DNA because while it is true that modern RNA is formed from DNA, the process could have been reversed and DNA could have arisen from RNA. RNA has been shown in the lab to be capable of making copies of itself and making proteins. Primitive life would have survived due to temperature differences in the water: heat travels from warm areas to cold areas and this would have supplied the chemical reactions with the energy needed to keep them going.\n\nLife would have existed like this for a couple of billions of years. The first adaption would have been to feed off of other life: modern cells trap smaller cells inside of them and digest them. Other adaptions would have been the ability to convert sunshine into sugar plus the ability to digest sugar. Nowadays it is plants and algae that can produce sugar whereas animals and fungi have to feed off of plants (ultimately) to survive.\n\nNow suppose you had two cells, one large cell that fed off of other cells and another small cell that converted sugar into energy. Now suppose that the large cell consumed the smaller cell but rather than digesting the smaller cell it fed off of the energy that the smaller cell produced. The smaller cells are what we now call mitochondria and they make it possible for large cells to have energy to survive.\n\nThe next adaption was for cells to work together. We have species of single cell organisms today that work together. The next adaption after that would have been for cells to differentiate and serve different functions. Thus you would have multi-celled organisms (plants, animals, fungi). It took billions of years just to go from dirty water to multi-celled organisms. "
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5yecc8 | what happens to food overproduction and waste? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5yecc8/eli5_what_happens_to_food_overproduction_and_waste/ | {
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"In restaurants, most of the time it gets thrown in the trash. That probably gets into a landfill or whatever trash disposal your city has.\nSometimes it might get mixed into other food but that probably happens only in very low end or Chinese food places."
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2nbzyc | how is this noise possible? | [It just keeps getting lower and lower! How is this possible??](_URL_0_)
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2nbzyc/eli5_how_is_this_noise_possible/ | {
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"If you listen closely, you can hear a new high tone starting about every 30 seconds or so. I'm sure the lowest tones in the sequence are fading out at a certain point although I can't detect it.",
"I saw a really cool explanation of this at a sound museum in Vienna and it blew my mind. I stood there for ever, listening and looking at the visualization. Essentially, you are hearing 6 tones at the same time, all of these tones are decreasing, which is why it sounds the way it does. However, because this is not possible forever, it remains stable as the lowest tone will fade away in volume, while a higher tone, fades in, yet still maintaining the constant downward trend of all of the individual tones.\n\nIts called the [Shepard Tone](_URL_0_)",
"It's called a [Shepard tone](_URL_0_).\n\nBasically, a tone fades out as it descends in pitch. As it fades out, another tone fades in, an octave higher. Tones an octave apart tend to overlap in your brain (they are perfectly consonant) and you don't notice the overlap. You perceive it as one continuously descending pitch.\n\nEven better, there are a few tones doing this at the same time, which really drives home the illusion.\n\n"
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3rq3pw | why is it more comfortable sometimes to lay on a hard surface like the floor instead of a soft surface like a bed? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3rq3pw/eli5_why_is_it_more_comfortable_sometimes_to_lay/ | {
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"Helps with spinal alignment, firm beds provide more spine support versus a soft one that's why a floor feels good, provided you're on your back"
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1tw6n7 | why do some deaf people oppose reparative surgery/implants? | I've heard it compared to skin lightening, circumcision, ambiguous genital reassignment, lesbian/gay reorientation therapy, etc. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1tw6n7/eli5_why_do_some_deaf_people_oppose_reparative/ | {
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"A lot of it has to do with the fact that they don't feel they fit in with either Deaf or hearing culture because of the implant. Cochlear implants don't give you the same hearing capabilities as natural hearing, plus they're a thing stuck on your head, so a Deaf person with a CI will stick out, but because of their controversy in the Deaf community they are often times rejected by fellow Deaf/hard of hearing people. \n\nDISCLAIMER: I am not a Deaf person, this is just what I've been told by Deaf people I know."
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d9kxnr | if the war on drugs has proven to be a failure, why are most governments focused on incarceration instead of rehabilitation? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/d9kxnr/eli5_if_the_war_on_drugs_has_proven_to_be_a/ | {
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"1. Not everyone is convinced the war on drugs has \"proven to be a failure.\"\n2. Many people interpret \"tough on crime\" to mean \"tough on criminals.\" That the most appropriate way to deal with crime is to have harsh sentences. Creating criminals in a humane way by trying to \"fix\" them is seen as being weak on crime.\n3. People profit from high incarceration rates and use that money to influence government officials to keep those policies in place.",
"Not most. Lets pick on the US: the reason why prisons in the US in particular are so focused on incarceration instead of rehabilitation is because prisons are a for-profit industry. Few state or federal prisons are run directly by the various departments of corrections, the majority of them are run by contract prison companies. These in turn seek to maximize profits by cutting costs, cramming prisoners into otherwise deplorable conditions (look at any jail cell in say Sweden or Denmark vs. a US prison) and seeking to keep as many people incarcerated as possible. Not only that, they have a huge lobby group who wine and dine congressmen and senators to ensure legislation that continues to prosecute and keep incarcerated as many people as they can.",
"Because for fifty years the conversation has gone \"drugs = bad\" and few politicians have been bothered to try to change that, unless they've really had to (i.e. Portugal).\n\nAppearing to be tough on crime is a usually a safe vote winning strategy and it's much easier to continue saying \"drugs = bad\" than explaining to people - particularly a disengaged voter base - why it's cheaper and better for society in the long run to rehabilitate people. \n\nAnd many people, even having heard the arguments for decriminalisation and rehabilitation still say have a deeply held moral panic about drugs. Over the course of last summer in Australia half a dozen people died having taken dodgy ecstasy at festivals. There were calls for pill testing which the government avoided - and it wasn't uncommon for people to say, of the people that died, \"good, thats what you get for taking drugs\". Try selling rehabilitation to a voter base that thinks people deserve to die because they take drugs.\n\nAlso, particularly in the USA but elsewhere as well: the prison industrial complex.",
"The \"war on drugs\" has not failed - in fact, it has been a massive success! See, the thing is that it was not intended to reduce drug use or sales, so you can't judge it based on those measures. It was intended to punish hippies and African Americans, and that's exactly what it has done.\n\nSounds like some crazy conspiracy theory, right? Don't worry, you don't have to believe Some Random Dude On The Internet. We'll let Nixon's adviser John Ehrlichman explain - in his own words, quoted directly, on the record:\n\n > \"The Nixon campaign in 1968, and the Nixon White House after that, had two enemies: the antiwar left and black people. You understand what I'm saying? We knew we couldn't make it illegal to be either against the war or black, but by getting the public to associate the hippies with marijuana and blacks with heroin, and then criminalizing both heavily, we could disrupt those communities. We could arrest their leaders, raid their homes, break up their meetings, and vilify them night after night on the evening news. Did we know we were lying about the drugs? Of course we did.\"\n\nAfter that, Reagan created rules to massively increase civil asset forfeiture in drug-related cases, and increased the FBI's drug enforcement budget by literally 1,180%. Why such a massive increase? Because \"civil asset forfeiture\" means that if someone is accused of dealing drugs, the authorities are allowed to seize any property or cash that they think is connected to the drugs. The person doesn't have to be *convicted* of dealing drugs, either, just *accused*, so spending more money on enforcement means that you can seize a lot more assets and make a massive profit - a report from 2014 said that the Justice Department had taken in *five billion dollars* that year from civil asset forfeitures, for example.\n\nNow, consider the for-profit prison system, where privately-owned prisons are specifically set up to make money off of having as many people as possible people in jail. And, hey, look, the war on drugs was already set up to throw huge amounts of people in jail, and it even specifically targeted people who were more likely to be poor and therefore less able to fight against the legal system! It's a great match for a corporation that needs lots of people in lots of jail cells so that it can make the largest possible profit.",
"Because people still get elected by being \"tough\" on drugs.\n\nDrug addiction is a complex problem, but voters want simple solutions, lock 'em all up is about as simple as it gets. Also, people who are against recreational drug us are *really, really* against it and will vote against anyone they don't think agrees. People who are more tolerant usually aren't as passionate about it and aren't going to care as much about a candidates views on the matter. So the \"safe\" (i.e., morally cowardly) approach is to pander to those to are strongly against drugs while trying to win over everyone else on other issues.\n\nFinally, drug use is kind of like speeding. It is a violation lots of people commit that police usually ignore, but like to have in their back pocket in case they need leverage.",
" > If the war on drugs has proven to be a failure\n\n\nThere is your problem. Logical fallacy - complex question, or possibly begging the question. There is no objective proof that the war on drugs is a failure, because there are no defined check-points (i.e. what is success and what is failure)."
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3syb4q | why do some fluids (like honey) become much more viscous when cooled while others (like water) have a viscosity seemingly independent of temperature? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3syb4q/eli5_why_do_some_fluids_like_honey_become_much/ | {
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"Actually, water *does* get more dense with lower temperatures (in liquid form, not as ice) but it isn't as noticeable. It happens to be only a very slight change, less pronounced because it isn't as dense at room temperature."
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1czxk0 | what is panentheism and what do panentheists believe? | The wikipedia page on this subject was possibly the most confusing thing I've ever read. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1czxk0/eli5_what_is_panentheism_and_what_do_panentheists/ | {
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"They believe that god or gods exist as an omni-present force that permeates and makes up the entire universe.\n\nAdd in lightsabers and brown robes then you'll basically have Jedi."
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5etvmw | why do a majority of "as seen on tv" products cost $19.99? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5etvmw/eli5_why_do_a_majority_of_as_seen_on_tv_products/ | {
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"Psychologically the number looks less expensive than $20 and so people are more likely to buy it.",
"From _URL_0_\n\n > Ending a price in .99 is based on the theory that, because we read from left to right, the first digit of the price resonates with us the most, Hibbett explained. That's why shoppers are more likely to buy a product for $4.99 than an identical one for $5 the item that starts with a 4 just seems like a better deal than the one that starts with 5.",
"People are commenting about how 19.99 seems less than 20 but OP was asking about the consistency of the price across a wide range of products on TV. ",
"I think OP might be referring to the fact that everything is marketed at $19.99, not the psychological impact of the .99. In which case I would say that the product was initially designed to be produced and manufactured in such a way that they can still make profits yet still be cheap enough that it can be considered worth buying. If someone came on the TV advertising a $300 blender people would dismiss that as way too much money and lose interest, therefore a lot of people don't bother producing expensive items.\n\nYou'll notice, however, that the expensive items use Payment Installments. Four easy payments of $39.99. That makes the item seem more affordable until you put some more thought into and realize you're paying $160 for an item. But a lot of people may not think that much about that and just go for it.",
"A lot of those infomercials use installments so it's really not just $19.99. But I also think they have a lot of people coming to them with products/new inventions and want to make an infomercial for it and they get denied because it's either too expensive or too cheap. Part of the allure of infomercials is not only the ability to talk about something's featured at length, but to also be able to market it at a price that seems like a great deal.",
"It's an impulse buy, something you don't need and the $20 price point is enough to cover shipping and material costs with profit after advertising while being inexpensive enough that most people won't think twice about buying it.",
"Those types of commercials lend themselves to easy A/B testing, ie. running the same commercials with different prices at different times/different channels/different media markets... so at some point it was probably tested, and determined that was the price where it's still an impulse purchase where people react immediately to buy. Once they knew that, then that's probably a big criteria in developing/selecting products to market in that way.",
"$19.99 is a price at which many consumers will buy on an impulse rather than deliberate about whether the item in question actually provides $19.99 or more of benefit to him/her. "
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3fwrw5 | how do complex devices like big rgb keyboards or high quality microphones all work with usb ports' 4 pins? | Like, it seems like you wouldn't be able to detect large amounts of keys being pressed at the same time (but you can), and it seems like the microphone wouldn't be able to transmit the audio realtime. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3fwrw5/eli5_how_do_complex_devices_like_big_rgb/ | {
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"Many years ago, keyboards used different pins to represent each bit of information. When some keys were held down, a different set of pins would have voltage across them than others.\n\nUSB doesn't work that way at all. It just sends data back and forth, one bit at a time, very quickly. It's a lot more like sending data across a network.\n\nWhen you hold down multiple keys, it just sends more bytes of data.\n\nWhen you record audio, it's digitizing the audio and streaming the bytes directly to your computer.\n",
"Professional audio is recorded at least 44,100 samples per second, with 24 bits per sample. That's a data rate of around 1060 kb/s. \n\nUSB 2 supports a data rate of up to 480 Mb/s. That's around 47 individual microphones all at the same time. \n\nIt works because USB is a serial communication with high speed switching. Meaning it sends two bits down the data pins, and rapidly switches between which bit is being sent. It switches literally millions of times a second, plenty fast for audio. ",
"The USB 2.0 (most common) standard has support for data transfer speeds as high as 480 Mbps (more than enough to handle audio and most video input streams). \n\nThe new USB 3.0 standard supports data transfer speeds of up to 5 Gbps and USB 3.1 supports up to 10 Gbps (which is enough bandwidth to handle just about any multimedia peripheral device you can possibly think of including live 4K video streams, for example).\n\nOf the 4 pins in a regular USB 2.0 cable, only 2 are used for data and the other two are used for supplying voltage/power.\n\nThe USB device has a chip in it that converts the information (e.g. audio information from a microphone or keyboard presses) into packets of data that can be transferred via USB to the receiving device (computer). That's why you don't need multiple wires for carrying different types of data, it all just gets converted into one data stream.\n\nNote that newer USB implementations (3.0 / 3.1) have more than 4 pins to facilitate higher speed data transfers / greater bandwidth.",
"The reason you can detect large amounts of keys pressed and record high quality audio is that the USB device is its self a little computer. It has enough circuitry to detect all the key presses and record the audio and then it packages all that data into a single stream of bits, and it's the bits that get sent back and forth over the USB connection. \n\nIn fact, this data is only sent over two of the four pins. The other two are used only for delivering power to a USB device that doesn't have its own power supply.\n\nThe reason the microphone can transmit in very very close to real time is that sound is very slow compared to have fast computers are.\n\nSound is a wave of changing air pressure that moves through the air. The higher the tone or pitch, the faster the air pressure changes neutral to high to low and back to neutral. The highest frequency humans can hear is 20KHz which means the air pressure makes that cycle 20,000 times a second. \n\nTo record this sound a microphone is setup which converts the air pressure into a voltage that swings from low to high and back, just like the air pressure. This changing voltage is then \"sampled\" by a converter circuit. Sample here just means to measure. So the voltage is measure to see how high it is at a given point. If you do this over and over again, and you do it fast enough, you get enough measurements to recreate the original sound with an amplifier and speaker.\n\nTo get enough samples to do this, you need to measure twice as fast as the highest frequency in order not to miss the really fast changing voltage. Recall the highest was 20,000 times a second. So we sample at 44,100 times a second. \n\nNow lets check some numbers. Each sample requires 16 bits of data and there are 44,100 samples per second so that is 705,600 bits per second. Most USB audio interfaces can record two channels at the same time, and play back two channels at the same time, so now we need to move 2,822,400 bits per second. Sounds like a lot. Except even the slowest USB devices can send 12,000,000 bits per second. So we can do 4 channels of high quality audio and still have 10,000,000 bits per second left over.\n\nNow sending audio data to the computer actually uses a lot more of that 12,000,000 bits per second because the audio has to be packaged in a way that the computer understands what it is and where it goes and that's done by wrapping the samples in other data.\n\n\n"
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2jq0rl | how do keygens (key generators) for cracked games and software work? | And why can't developers make their programs only accept the keys they have generated themselves? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2jq0rl/eli5how_do_keygens_key_generators_for_cracked/ | {
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"That is how keygens DO work generally. The developer makes a bunch of keys they generate themselves. Then someone on the internet figures out how they generated them and releases a program that generates them too. ",
"The games are built to recognise certain keys, the official ones. What crackers do is go into the program, read what the program is looking for, and then work out a generator that will give the game what it wants.\nCracking is different, the software will run like a flowchart, and there will be a point where it will read the key and decide yes/no whether it is valid. Cracking involves re-writing this bit of the program so it always goes down the \"ok\" route. Developers make these harder, the crackers, patchers and hackers work harder to get round it."
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7fsj61 | what are the mechanics of throwing? why do we point our non-throwing arm at the target then drop it as we move our other arm forward? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7fsj61/eli5_what_are_the_mechanics_of_throwing_why_do_we/ | {
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"This boils down to generating as much force as possible.\n\nThink about how something like a trebuchet works -- there's a heavy counterweight that swings down, and this creates a ton of rotational force.\n\nYour non-throwing arm is doing the same thing. You point it out, then swing it back through your shoulders, generating extra force in your throw. The weight and momentum of that arm helps to propel the throwing arm forwards."
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3r5au2 | why can't radio waves penetrate deep underground? | is it the dirt? impurities? the density? moisture? simply the distance? what is the actual scientific reason you wouldn't be able to communicate via radio deep underground? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3r5au2/eli5_why_cant_radio_waves_penetrate_deep/ | {
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"I'm not a scientist by any means... But I think it's because of the molecular density of matter and how radio waves travel through that density. The tighter the bonds, the less room waves have to travel through and/or the less the matter is capable of carrying the waves. \nI think it's the same with sound waves... When I was younger I recall a diving instructor telling me that sound travels 4 times faster through water and even faster through solid matter. But it requires more force to penetrate further \n\nI could be completely wrong... My memory isn't as trustworthy as I would like it to be",
"Radiowaves can. You need to have enough power, and at the proper frequencies. The trouble is that soil has a lot of stuff in it that can absorb the radio waves...so you would need to have very powerful transmitters and/or very directional (high frequency) receivers. Not always practical. Metals and finely grained materials (like clay) can scatter the signal, and anything with a high carbon content (coal) can absorb it.",
"As I write this, there are two comments; both have elements of the explanation, but neither lays it out.\n\nRadio waves are electromagnetic radiation. They only differ from heat, light, xrays in frequency of oscillation. Now, an electromagnetic wave propagates through nothing, it is a field whose wavefronts travel at the speed of light in the medium.\n\nThe speed of light is the trick there: Radiowaves are basically invisible light. Imagine a blinking light on top of a pole on a hill, if you could see it and knew the code, you could read the BBC. But say you cannot see the light, rather, you can see the reflection of the light off the hill beside you (it's a *very* bright light), you can still read the BBC.\n\nRadio waves have a wavelength that is longer than visible light, and so bounce and curve through things more effectively than visible light. This is why it is easy to get radio anywhere in the house when sunlight only gets in sort of.\n\nSo why can radio not reach underground? Simply put, the material of the earth is sufficiently thick to absorb and attenuate the wave-front below a level your receiver can distinguish it from noise. Even when there are openings to the outside, such as in a tunnel, the waves cannot reflect in a manner which can be received correctly, which is why you lose phone reception on trains.\n\n"
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p7k85 | null hypotheses | Why are they used? What necessitates the use of more than one hypothesis? Are they vital?
Thanks in advance, fellas. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/p7k85/eli5_null_hypotheses/ | {
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"There are two hypotheses. The null and the alternative. The null hypothesis states the status quo is true. The alternative hypothesis is the compliment (opposite), and is what you are trying to prove. So really, you're trying to prove that the \"accepted\" belief is wrong.\n\nYou cannot prove or disprove the null hypothesis. By collecting evidence you can either choose to reject or not reject the null hypothesis, but it is not possible to state with certainty that it is either true or false.\n\nPlease note I come at this question with a statistical background, not a philosophical one.",
"A null hypothesis is the situation where what you're testing for doesn't happen. It's like a control group.\n\nSo, for example if my alternative hypothesis was \"Red cars cause accidents\" then my null hypothesis would be \"Colour of car is not a cause of accidents\".\n\nYou would then gather data and use statistics to analyse which hypothesis seemed more likely.\n\nYou need a null hypothesis because otherwise it's difficult to judge whether the thing you're examining is the root cause or whether it's caused by something else. For example, you might find that red cars are involved in 500 accidents per day, so without a null hypothesis you would say \"Aha! Red cars are dangerous! We'd better get a green one!\". With the null hypothesis, you would check other colours as well and see that actually the colour of the car has very little effect on the likelihood of an accident.",
"The null hypothesis is the most important one. Science is only legitimate when it tries to **falsify** something. Science that affirms is not very legitimate. It's the science that disproves that is legitimate. Therefore, the best theories arise from multiple attempts at failing to falsify a null hypothesis. Alternate hypotheses should only be formulated after multiple failures to falsify a hypothesis.\n\nFor example:\n\nA famous null hypothesis would be that \"natural selection does not account for changing allele frequencies in a population of species.\" As thousands of studies and scientific papers show, no one has been able to reject this null hypothesis. It always is falsified. There is no evidence in the history of the theory of natural selection that shows that it does not occur. Therefore, it is will supported. \n\nWe have not proven that natural selection accounts for genetic change. We have merely never found counter-evidence showing that it does not account for genetic change. We have always failed to falsify the null hypothesis. "
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mb4xl | l'hopital's rule: how and why does it work? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/mb4xl/eli5_lhopitals_rule_how_and_why_does_it_work/ | {
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"For this answer I'm going to assume that you already know a little bit about the mathematical concept of *functions*, *limits* and *derivatives*.\n\nL'Hopital's rule is a way to figure out some limits that you can't just calculate on their own. Specifically, if you're trying to figure out a limit of a fraction that, if you just evaluated, would come out to zero divided by zero or infinity divided by infinity, you can sometimes use L'Hopital's rule.\n\nL'Hopital's rule says that the limit of the fraction (or of the ratio) is the same as the limit of the ratio of the derivatives.\n\nSo let's say that we have two functions, *f(x)* and *g(x)*. Let's say *f(x)=2x* and *g(x)=x*. Say we wanted to figure out the limit as *x* approaches infinity of *f(x)* divided by *g(x)*.\n\nNow, of course, we know that *f(x)/g(x)* in this case is just 2. But pretend we couldn't do that simplification. So the first thing we try to do is evaluate the limit as *x* goes to infinity of *f(x)* and *g(x)*. We get infinity for both.\n\nD'oh. We can't just divide infinity by infinity to get our answer, because that's an indeterminate form.\n\nSo instead, we take the derivative of *f(x)* (it's 2) and the derivative of *g(x)* (it's 1). We can divide those! The limit as *x* goes to infinity of *f(x)/g(x)* is 2 divided by 1, or 2!\n\nWhy did that work? Well, intuitively you can think of it this way. The derivative of a function is telling you how fast it's changing, right? We know that both *f(x)* and *g(x)* are approaching infinity, but the derivatives kind of tell us how *fast* they're approaching infinity. Since *f* is approaching infinity twice as fast as *g*, their ratio ends up being 2 even as they both approach infinity.\n\nThe same concept works when your indeterminate form is zero divided by zero.",
"For this answer I'm going to assume that you already know a little bit about the mathematical concept of *functions*, *limits* and *derivatives*.\n\nL'Hopital's rule is a way to figure out some limits that you can't just calculate on their own. Specifically, if you're trying to figure out a limit of a fraction that, if you just evaluated, would come out to zero divided by zero or infinity divided by infinity, you can sometimes use L'Hopital's rule.\n\nL'Hopital's rule says that the limit of the fraction (or of the ratio) is the same as the limit of the ratio of the derivatives.\n\nSo let's say that we have two functions, *f(x)* and *g(x)*. Let's say *f(x)=2x* and *g(x)=x*. Say we wanted to figure out the limit as *x* approaches infinity of *f(x)* divided by *g(x)*.\n\nNow, of course, we know that *f(x)/g(x)* in this case is just 2. But pretend we couldn't do that simplification. So the first thing we try to do is evaluate the limit as *x* goes to infinity of *f(x)* and *g(x)*. We get infinity for both.\n\nD'oh. We can't just divide infinity by infinity to get our answer, because that's an indeterminate form.\n\nSo instead, we take the derivative of *f(x)* (it's 2) and the derivative of *g(x)* (it's 1). We can divide those! The limit as *x* goes to infinity of *f(x)/g(x)* is 2 divided by 1, or 2!\n\nWhy did that work? Well, intuitively you can think of it this way. The derivative of a function is telling you how fast it's changing, right? We know that both *f(x)* and *g(x)* are approaching infinity, but the derivatives kind of tell us how *fast* they're approaching infinity. Since *f* is approaching infinity twice as fast as *g*, their ratio ends up being 2 even as they both approach infinity.\n\nThe same concept works when your indeterminate form is zero divided by zero."
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ktsib | does it make a difference if i choose to stream a tv show vs. downloading a torrent. is one safer for my computer? is one easier for someone to track? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/ktsib/eli5_does_it_make_a_difference_if_i_choose_to/ | {
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"If you stream the content it downloads as you watch. When you torrent a television series, you can't watch instantly. What happens is you take a little bit of the television series from a bunch of people. That little bit you get from everyone will compile into the whole television series. Streaming is safer when it comes to services like Netflix, and Hulu, but I would say that when streaming from services like megavideo the chance of getting hacked is there, but if you are intelligent won't affect you (going on the site won't instantly make your computer hacked you would have to do something like click on a javascript). Downloading a torrent would also only cause you to get hacked if you do something stupid (such as download a torrent without reading the comments first).",
"So here's an idea: Keep commercials in torrents of TV shows. Then networks might be a bit less sore about people torrenting their shows. I understand that most people would choose the torrent without commercials, but voluntarily choosing the commercial versions could legitimize torrenting.",
"Is there any real difference in bandwidth use between streaming and torrenting?",
"If you stream the content it downloads as you watch. When you torrent a television series, you can't watch instantly. What happens is you take a little bit of the television series from a bunch of people. That little bit you get from everyone will compile into the whole television series. Streaming is safer when it comes to services like Netflix, and Hulu, but I would say that when streaming from services like megavideo the chance of getting hacked is there, but if you are intelligent won't affect you (going on the site won't instantly make your computer hacked you would have to do something like click on a javascript). Downloading a torrent would also only cause you to get hacked if you do something stupid (such as download a torrent without reading the comments first).",
"So here's an idea: Keep commercials in torrents of TV shows. Then networks might be a bit less sore about people torrenting their shows. I understand that most people would choose the torrent without commercials, but voluntarily choosing the commercial versions could legitimize torrenting.",
"Is there any real difference in bandwidth use between streaming and torrenting?"
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1wl0di | why a technocracy would be a bad governing system. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1wl0di/eli5_why_a_technocracy_would_be_a_bad_governing/ | {
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"Technocracy means a government where those with the knowledge of technology (say, the ability to use super awesome battlefield robot soldiers) make the rules.\n\nImagine if you lived in a world where a \"noble\" who owned all the robots in the area decided he wanted your wife and daughter... so he orders you to give them up. If you don't.. he kills you and no one does anything about it because he makes the rules.\n\nThat's an extreme but relevant example. Democratic Republics at least have some systems where the less well off have a hope of being protected."
]
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912azc | how does a butterfly know how to use all of its body parts and wings seconds after leaving the cocoon? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/912azc/eli5_how_does_a_butterfly_know_how_to_use_all_of/ | {
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"text": [
"Because this isn't learned knowledge, it's wired right into the butterfly's nervous system — just as your heart knows to beat, and your intestines know to move food along."
]
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389u4e | how did they film this shot? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/389u4e/eli5_how_did_they_film_this_shot/ | {
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" > *\"the shot was filmed normally and flipped in post to achieve the mirror image. The actual bathroom mirror was replaced with a bluescreen into which the original shot was superimposed.\"*\n\nFrom a [previous Reddit thread](_URL_0_) about this.",
"It's two shots stitched together, the mirror is actually a blue/green screen. The main shot is filmed with the camera going backwards, the girl is just reaching where the knob should be. That shot is then put on the blue/green screen in the shot of the hand opening the cabinet.",
"What shot is this from? I would love to watch the rest of this.",
"[This](_URL_1_) guy from earlier today links to [this](_URL_0_) video which helped be understand how it was done. Even though it's not in english it helped me visualize the concept."
]
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"https://m.reddit.com/r/movies/comments/o5ojz/brilliant_mirror_shot_from_the_movie_contact"
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"http://www.reddit.com/r/gifs/comments/3865g9/one_of_the_coolest_shots_caught_on_film/crsu1xq"
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b2q4xx | chance of getting something with a 10% probability after 50 tries | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b2q4xx/eli5_chance_of_getting_something_with_a_10/ | {
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"As you spin the wheel the probability for your total set of 50 spins changes.\n\nAfter 49 losing spins the probability for the 50 spins is 90% that you'll have 50 losing spins and 10% that you'll have 49 losing spins followed by 1 losing spins. There is a 0% chance at this point that the 32nd spin will be a win, or any of the other permutations of the first 49 spins.\n\nAt any point the probability of your *next* 50 spins being 50 losses is 0.52%, and at any point the probability of your next spin being a loss is 90%. "
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3qgtos | the need to grade on a curve | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3qgtos/eli5the_need_to_grade_on_a_curve/ | {
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" > What's the point of having a class so difficult that 50% becomes a passing grade?\n\nIt allows the professor to accurately judge the performance of top students in relation to each other. If two students both get 100%, then all you know is that both of them are more proficient than everyone else, but you have no idea how they compare to each other.\n\nMaking an exam so difficult that no one can get 100% allows a better understanding of how *all* of the students are performing.",
"Well, the professor probably wants to make a very difficult test so that students who *really* get the material can excel and students are challenged to demonstrate a thorough understanding of the material. However, they want to judge performance relatively, rather than giving the bulk of students a very bad grade for a deliberately difficult test. It gives the class a chance to demonstrate if they've gained a really deep understanding of the material.",
"The problem is that anyone getting 100% on a test skews the average, making it harder to compare between students.\n\nHere's an example: let's say I make a medium-difficulty test, and out of a class of 20, 5 of them manage to get 100%. It's great for those guys, but what that means is that all of them achieved an equal grade, when it's very unlikely that each of them knows just as much as each other. You lose the ability to compare to the top of the class.\n\nNow, if I make the test so hard that no students get 100%, now we have accurate data. Everyone got the maximum possible score based on their ability and knowledge, and I can make an accurate curve that ranks all of them relative to each other. The fact that 100% acts as a ceiling ruins my ability to make this curve accurately. \n\nSo to ensure that this doesn't happen, professors (especially in the sciences) tend to skew the test towards the \"very hard\" end of the scale. Very low chance of perfect scores means an easier comparison between your top and bottom achievers.",
"In order to grade on a curve you need to be able to quantify the grades easily, which is easier in science and math since the test questions typically have specific correct answers. \n\nYou could try to do the same thing on an English paper, but what's the point in giving a 50% and then curving. You might as well \"apply the curve\" before handing the papers back unless you have a very specific and quantitative grading rubric.\n\nThe reason students get 50% on the tests isn't that the professors can't teach or that the material is too difficult. The reason is that the tests are supposed to purposefully get harder. You have to ask progressively more difficult questions to get a good grading curve. And good questions require you to apply the material, so it's a matter of both knowing it and knowing how to use it to solve problems. So if you get a 30% and that translates into a C+/B- or so, then you probably either didn't learn all of the material or aren't as good as applying it to problems on tests as those who scored better. You probably still know a good amount of the subject, though.\n\ntl;dr - Tests with progressively more difficult problems make it easier to establish a range of grades for the students while testing both their knowledge of the material and their ability to apply it and the final percentages don't really matter since you get curved up."
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1gq7c4 | how does anti-cheat systems like punkbuster or vac work? | Just wondering how it works and how it can be improved? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1gq7c4/eli5how_does_anticheat_systems_like_punkbuster_or/ | {
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"tl;dr: Similar to antiviruses. Match memory with database, block anything found.\n\n---\n\nIn ELI5 terms:\n\nImagine you're going to cheat on a test. Some guy gives you a cheat sheet, tells you these are the answers to the test. You put the cheat sheet in your pocket and use it to pass the test. Now, suddenly, everybody starts passing the tests. So teachers hunt down your friend and after investigating him, they notice that he's giving people cheat sheets.\n\nNow, in an attempt to stop this, teachers start patting down students taking tests looking for \"cheat sheet\". Soon as a matching cheat sheet is found, the student is banned from taking the test.\n\nSo your friend ups his game and now starts sending text messages to students with the cheats. Teachers notice that something's weird when students start passing all tests. They investigate your friend, notice he's sending texts, and now teachers start searching students for \"cheat sheet\" and \"mobile phone\".\n\n---\n\nSomething like PunkBuster reads the player's computer's memory for matching signatures existing in the database. Every software you run exists in your memory as it runs and has a particular footprint. The developers of PunkBuster study these bots, find out what they look like in memory, and put it in a database. PunkBuster then scans your memory and if anything fits the signatures in the database, it blocks you.\n\n---\n\nPunkBuster has a bunch of other functions to make it more efficient. But this is the core.",
"From what I can tell they don't!\n",
"Punk buster actually takes a photo of your screen as well and references it against another image they have to look for GUI hacks and such. \n\n",
"Thanks everybody for your replies.",
"Remember anti cheat systems work pretty much like anti viruses, so they are limited, but they will catch most cheaters, but unfortunately they can't always keep up with new kinds of cheats.\n\nMulti player game server code can also check if you're doing things out of bounds, like speed hack. Problem is, some cheats are vicious, like for example, the stalker blink/roach burrow cheat in starcraft 2, or aim bot.\n\nI guess that there are also ways to program a game to prevent other executable to modify/call another specific game executable code, or maybe on the OS level.\n\nAnyways, anticheat are overrated, the best way to prevent abuse, is putting bounds, monitor multiplayer events, but also allowing players to votekick and report players for cheating, so that game progammers can investigate.",
"One thing I do know is that VAC checks memory.\nTypical hacks inject into the games memory and are usually detected by VAC. "
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2r5qkv | ambulance workers and first responders, what is the protocol when the phone of an injured person rings? would you answer and let the other person know? how do hospitals let loved ones know when there's been an accident? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2r5qkv/eli5_ambulance_workers_and_first_responders_what/ | {
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"I don't quite get what you're asking, but as a former EMT, we fundamentally have nothing to do with the hospital beyond letting them know what treatment was rendered en route. The hospital is usually the ones, then, who notify people related to the patient."
]
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3hfccy | is a satellite orbiting the earth (falling indefinitely) not technically a perpetual motion machine? | Can we not harness, somehow, its kinetic energy? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3hfccy/eli5_is_a_satellite_orbiting_the_earth_falling/ | {
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"Reducing its kinetic energy would drop it into a lower orbit until the atmosphere deorbits it. \n\nBesides to put the energy into it we need to use rocket fuel.",
"In the completely idealized case of one object orbiting another in a complete vacuum, ignoring relativistic effects, yes. But that isn't a real-world case: there is no such thing as a true vacuum, so there is always some drag, and relativistic effects cause orbiting objects to lose energy in the process of generating gravitational waves.\n\nEven in the idealized case, trying to harness its energy (e.g. by attaching a magnet to it which induces a current as it flies by) would sap its kinetic energy, causing it to drop into lower and lower orbits until it impacted whatever it was orbiting.",
"A perpetual motion machine, by its definition, outputs more energy than it consumes. It's physically impossible. Satellites that orbit the Earth won't remain in the same orbit indefinitely without an input of outside force. See here: _URL_0_",
"It is not, even if it orbited for all eternity its still not a perpetual motion machine because you cant do anything with it. The moment you try to use the orbiting satellite to do work you take energy from it which will slow it down and its orbit will begin to decay, eventually crashing back to earth."
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98c06f | if a country gets invaded, what happens to it's currency? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/98c06f/eli5_if_a_country_gets_invaded_what_happens_to/ | {
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"The currency becomes worthless. However nonmonetary assets still retain value and will be priced in whatever currency becomes standard. Rich people, especially, hold a large portion of their wealth in nonmonetary assets (real estate is a good example)",
"It depends on whether the invasion was successful, and if so, what the conqueror chooses to do. It could go to zero, or the conqueror might keep the monetary system in place, or establish a way to convert old currency to whatever new system they impose.\n\n > Do the rich people instantly become poor?\n\nRich people almost never hold their wealth as currency, despite what poor people seem to think. The conqueror might maintain the property registry, or might not. They might maintain the stock market, or might not. They might round up the existing power structure (which is often the same thing as the wealth structure) and execute them, or they might leave them in place and demand that they change allegiance from the old guard to the new guard."
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o4vmq | the good/bad things obama has done as a
president | Maybe belongs in r/politics. (sorry...) I don't mean anything about why there are people that do want/don't want him re-lected. Mainly pertaining to what has happened (factually good/bad) since his inauguration with him as our president, in a nutshell.....like I'm 5. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/o4vmq/eli5_the_goodbad_things_obama_has_done_as_a/ | {
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"**Good:** \n\n-Killed Osama\n\n-Stimulus package stopped economic collapse from being worse\n\n-Intervention in Libya went well, got rid of Qaddafi without huge commitment\n\n-Some parts of his healthcare law, like making insurance companies take people with preexisting conditions and preventing them from taking away a person's insurance if they get an expensive disease.\n\n-Got rid of 'Don't ask don't tell'\n\n**Bad**\n\n-Has massively expanded drone assassination program and claimed right to kill American citizens with no legal oversight\n\n-Patriot act extensions and immunity for telephone companies who helped government illegally spy on citizens\n\n-'Surged' troop levels in Afghanistan, even after the elections were rigged and it was clear we weren't doing any good.\n\n-Some parts of the healthcare law, like how it gives private insurance companies a ton of money through 'health care exchanges.' Offering Americans access to Medicare would have been a lot cheaper and gotten them better coverage. \n\n-Has repeatedly 'compromised' with Republicans. Except he hasn't gotten anything in return for compromises so he's actually caving\n\n-Created Simpson-Bowles commission on national debt, then totally ignored their recommendations.\n\n-Went after medical marijuana even though he promised not to and continued war on drugs even after saying it wasn't working.\n\nThere's more, but this is what comes to mind at the moment. Obviously people can disagree about whether some of these things are bad or good.",
"Well, he found his birth certificate. Wasn't a big deal to me, but a ton of people seemed really, really concerned about it, so it must have been a big deal.\n\nMeanwhile, in Canada, we elected a guy who ran on a platform of doing a televised speech while holding a kitten. No, really, a live, adorable kitten.",
"(edited) \n**Good** \n-Prevented a 2nd Depression through the stimulus \n-Helped America's auto industry get back to profitability \n-Healthcare reform which helps more people afford healthcare \n-Repaired America's image abroad \n-Completed withdrawal from Iraq \n-Helped topple Gaddafi \n-Killed Osama Bin Laden & top al Qaeda ops \n-Dont ask dont tell repealed \n-Nuclear treaty with russia \n-Trade deals with asian countries \n-Created consumer protection agency \n-Increased power in asia through partners\n-Allowed states to opt out of No child left behind \n-and more.. \n \n**Bad** \n-Signed Patriot Act \n-Compromised with Republicans (without getting much in return) \n-Continued Bush tax cuts for 2 more years (made deficit reduction harder) \n-Misspent some of stimulus \n-Did not appear business friendly enough in 1st 2 years \n-Relationship with Pakistan has deteriorated \n-Allowed Wall street to get away without enough punishment \n-Continue crackdown on marijuana dispensaries \n-and more... ",
"Refuses to investigate members of the previous administration over torture. This sets, or strengthens, a chilling precedent.",
"This only focuses on the Good, but it's an easy read: _URL_0_",
"Can someone juxtapose the good and bad to his campaign promises? Because if he campaigned to do something labeled under your definition of BAD then that is solely your opinion and not his failure. I see whatever is labeled under BAD as broken campaign promises. ",
"in my opinion a leader should just put the idea in motion and have the people follow the momentum. a country should be reflected on how the people carry each other not how a group carries them",
"A lot of good/bads were listed. But, the one thing I didn't see listed that was good: Signed Matthew Shepard and James Byrd, Jr. Hate Crimes Prevention Act. (Protect the rights of gays) ",
"1. He has been *disastrous* for civil liberties. Not only has he expanded on bush administration policies (warrantless wiretapping / eavesdropping), but because of who he is, nobody protests anymore.\n2. He has assumed incredible powers for the executive branch. He has murdered an American citizen without any due process.\n3. He has expanded the drone program *immensely*.\n4. He has seriously cracked down on whistleblowers, and led one of the most secrecy obsessed governments in history, although he promised the \"most transparent.\"\n\nHe has been George W Bush Redux, but because of who he is, it is much more accepted. No more hatred or protesting. \n\ninteresting articles:\n\n[Why do liberals keep sanitizing the Obama story?\n](_URL_0_)\n\n[GOP and TP on Obama's Foreign Policy \"successes\"\n](_URL_2_)\n\n[Progressives and the Ron Paul Fallacies](_URL_1_)\n\nTL;DR - Barack Obama has been pretty similar to GWB, and actually expanded on some of Dubya's worst policies. He has also seriously consolidated power in the executive branch, and eroded the rule of law.",
"We're conflating the Executive and the Legislature.",
"To promote his green energy initiative he authorized the US government to loan $535 million dollars to a company called Solyndra, which produces solar panels for homes. After the initial loan Solyndra promised 5,000 jobs and energy efficient solar panels. Note the fact that Solyndra 'donated' over $1 million dollars to Obama's election campaign and thus were the first to receive such a loan. Two years later Solyndra reduced its staff and filed for bankruptcy. Now its executives are testifying in front of Congress as to where the $500 million dollars of taxpayer money has gone and they won't answer a single question as they are pleading the 5th. Add to this the fact that almost no news coverage of this scandal has been shown on television, newspapers, etc. and I am beginning to think something is not right here. .\n\n[1](_URL_0_)\n\n[2](_URL_1_)",
"I'm impressed that this question didn't degenerate into a political cluster fuck, thank you ELI5.",
"ELI5: How to get everyone to argue."
]
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[],
[],
[],
[],
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"http://www.theatlantic.com/politics/archive/2011/11/why-do-liberals-keep-sanitizing-the-obama-story/248890/?MIAOU",
"http://www.salon.com/2011/12/31/progressives_and_the_ron_paul_fallacies/singleton/",
"http://www.salon.com/2011/11/13/gop_and_tp_on_obamas_foreign_policy_successes/singleton/?MIAOU"
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[],
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"http://en.wikipedia.org/wiki/Solyndra_scandal",
"http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2011/09/24/MNIA1L8LBS.DTL"
],
[],
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dslsli | how is it that we are able to cut down 3.5-7 billion trees a year? and why are so many needed? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dslsli/eli5_how_is_it_that_we_are_able_to_cut_down_357/ | {
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"A good number of them are planted for that sole purpose - 500 fast growing pines per acre that are on 15-20 year rotations and then brought down for lumber and wood pulp.\n\nThey're used for construction, paper production, pencils, woodchips...",
"Furniture, building material and paper need substantial amounts of wood, most woodlands are managed so that new trees are planted as old ones are cut down.",
"Trees are cut down for 2 major reasons. Because we want the wood for lumber as a building material. Or because we want the land to grow crops or cattle or build housing.\n\nLumber industry at least in North America is pretty much self sufficient. They cut down a billion trees and plant a billion in place to grow and cut down in 10 years.\n\nIn places like south America, the Amazon is being cut down to make cattle farming land. The trees won't be replaced."
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5k0se4 | how did ellen degeneres get so famous and successful? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5k0se4/eli5_how_did_ellen_degeneres_get_so_famous_and/ | {
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"She was a good standup comedian, and did some voice-over work for movies, but I don't think she really blew up until she got the talk show. She has a large and loyal audience whom she's giving something they had lost from the departure of both Rosie O'Donnell (she was the former host of basically the same show in the same time slot) and Oprah.",
"1. She was a pretty great stand-up - very successful, televised special, dvd sets and the all the hallmarks of 90s success in comedy.\n\n2. She then had a sitcom that did well too. \n\n3. On said sitcom she was gay, had a partner and they kissed - first real gay kiss on TV. This made her not only successful, but very controversial. Many suggested that this would kill her career.\n\n4. Talk show."
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2euwt5 | why do animals (including humans) close their eyes during physical pleasure of any sort? e.g. massages, petting | Title | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2euwt5/eli5_why_do_animals_including_humans_close_their/ | {
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"text": [
"It's a sign of Trust.\n\nEye contact in the animal kingdom is generally a threatening expression. Closing the eyes is a signal that 'I don't think you will hurt me'.",
"The mind can only handle so many stimuli at once. Try to use two senses at once. Now add a third without detracting from the other two. Now add another. Eventually (usually at adding the third) you will notice that it's difficult to focus on all the sensations at once.\n\nClosing your eyes allows your brain the extra processing power that was being taken up for that to better focus on the pleasurable sensations."
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28nnwa | how do they not know if the quantum computer is real? | There is this debate going on about the dwave machines and whether they are quantum or not.
Can you please ELI5 why the answer is not obvious? Wouldn't a quantum computer be built with completely different hardware parts than an ordinary one?
Edit: The reason why I ask is this study which google/micrsofot released about their tests:
_URL_0_ How can this even be a discussion? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/28nnwa/eli5_how_do_they_not_know_if_the_quantum_computer/ | {
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"I posted nothing...",
" > _URL_0_\n\n > An article in the May 12, 2011 edition of Nature gives details which critical academics say proves that the company's chips do have some of the quantum mechanical properties needed for quantum computing. Prior to the 2011 Nature paper, D-Wave was criticized for lacking proof that its computer was in fact a quantum computer. Nevertheless, questions remain due to the lack of conclusive experimental proof of quantum entanglement inside D-Wave devices.\n\nAnother issue is that generally speaking the public's perception of a \"quantum computer\" doesn't involve quantum entanglement, but rather the use of *quantum dots* to replace transistors (which may not even be possible). Quantum entanglement is useful for producing certain results, particularly with regards to encryption, but most of the advantages that you've heard about with regards to a hypothetical quantum computer involve quantum dots."
]
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"http://www.engadget.com/2014/06/20/d-wave-quantum-computer-test-results/"
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[],
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zgs6l | the run-time stack in a computer | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/zgs6l/eli5_the_runtime_stack_in_a_computer/ | {
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"Imagine that you're working on some paperwork at your desk. Let's say it's your taxes. You're working on the basic 1040 form when you get to an instruction that tells you to calculate one of the numbers using a different form. So, you put the 1040 down on your desk and grab this new form and start working on it. This new form also tells you to calculate yet another number using yet another form. So, you put the form you're holding on top of the stack on your desk and go grab this even newer form.\n\nWhen you're finally done with the third form you take the result from it and write it in on the second form that is on top of the stack. You finish working on the second form and take the result from that and write it in on the original 1040.\n\nDoes that make sense?",
"Computers deal a lot with function calls. There are changes in the program flow to compute some quantity of data. These function calls exist only once in memory, but they may be called at any point in the program flow. So they need to have a way to get back to where they came from in an agnostic way.\n\nSo let's say at address 0x03, there's a call to a function at address 0x10. So the caller 'pushes' the address (0x03+1)=0x04 on the top of the stack, representing the next address to return to after the function is done. It then changes the program counter (PC; the next instruction to execute) to the address of the function. When the function is done, it 'pops' the address off the top of the stack, and changes the next instruction (PC) to that address. And we continue where we left off.\n\nBeyond the scope, but the arguments to that function and the return value from it are also communicated on the stack."
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4p4e81 | why did people in photographs from the 19th and early 20th centuries always look so mad/mean/never smile? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4p4e81/eli5_why_did_people_in_photographs_from_the_19th/ | {
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"When they took photos they had to stand for a few minutes while the image made an impression. It's extremely hard to maintain a smile. ",
"Taking photos has gotten MUCH faster over the years. Today it's just a flash and the picture is done, but in the past it would take a LONG time.\n\nSo the photographer would press the button to take the photo, the camera would expose the film to the light and it would take 15 minutes or longer (it would fairly quickly drop down to about a minute, but still). The person getting their photo taking would have to remain perfectly still the entire time. It's hard to hold a smile that long, so they simply did not smile. ",
"In addition for standing still for minutes at a time, the photographs were rare and would probably be the only one they ever displayed. So they would dress up formally and have a formal expression; you don't get a portrait painted with a goofy grin."
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6soyxd | how do you keep time on a long haul boat journey? surely new time zones are entered very frequently? | On a cruise from the UK to America for example, are passengers told to update their watches every time a new time zone is entered? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6soyxd/eli5_how_do_you_keep_time_on_a_long_haul_boat/ | {
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"Generally the ship picks a timezone and sticks with it. Military ships use GMT (aka Zulu time), civilian ships use whatever time they'd like (many use whatever time zone the company HQ is in). Cruise ships that traverse multiple time zones usually do update the clocks for the passengers at port calls just to prevent things from becoming too confusing."
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7hm6ae | can hardware work without drivers? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7hm6ae/eli5can_hardware_work_without_drivers/ | {
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"No. The drivers make the hardware work. Some operating systems put drivers in the kernel and some have them separate, but in most cases drivers are needed, like for printers and things like that.",
"Short answer: No\n\nImagine your computer is person A and your other hardware (Lets say a monitor) is person B. Person A wants to tell person B is to flick the light switch. The driver defines how they will communicate. Maybe it's English, maybe it's sign language. But without it, no matter what person A does, person B has no idea that person A wants them to turn on a light switch. And there is no way person B can tell person A that there is no light switch in the room. \n\nPlug and play hardware works because a bunch of companies got together and told everyone else that is going to make a generic type of device (eg monitors, mice, keyboards, etc) that they need to speak in english back and forth if they want generic functionality to work. If the need to do something fancy, like sing, they can write their own language. But if they want to talk, they need to speak in English. For a lot of stuff, like mice and keyboards, this is enough. For other stuff they actually need to sign... and dance... and throw pies in people's faces. They need their own language.",
"A driver is, by definition, the software that allows your computer to interface with hardware. For modern operating systems that do not let programs directly access hardware, there must always be some sort of driver telling the OS how to use that hardware.\n\nThat driver might be a generic driver that came with the OS rather than something specific to that piece of hardware (eg - standards compliant USB keyboards and mice or running a video card as a generic VGA adapter) but there's going to be a driver in there somewhere."
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6dnesx | what really happens when everyone in a building flushes their toilets at the exact same time? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6dnesx/eli5_what_really_happens_when_everyone_in_a/ | {
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"If it's a modern building and there are no obstructions in the waste line, the toilets will all flush normally. The water service is sized to supply every fixture at the same time. The waste lines are as well.\n\nEdit - Apparently that isn't true for a skyscraper though, I never built one of those.",
"We did this at our High School back a lonnnngggg time ago. After a few unsuccessful attempts due to lack of timing we initiated \"Operation Royal Flush Phase IV\". At the bell all toilets were to be flushed, all taps turned on at the sinks. All tolled there were probably two or three hundred fixtures.\n\nAt the bell we all did our thing...I was in the B-200 wing Men's washroom...\n\nFlush.......a slow gurgle.....the water down the trap then........nothing..........then....... a low rumble.....then.....you could feel it coming.......every toilet and sink literally exploded with regurgitated liquid.....hitting the fan......omg nothing so grand had ever been seen before it was a total success. Even more so as they had to close the school for a week to get it back in shape....",
"Obviously the answer is \"the waste lines will revolt, backup from the pressure and spray your entire bathroom and kitchen with liquid shit.\" ",
"Iirc they had to do this in a South American city. Due to water rationing the waste wasn't getting discharged properly, causing a severe blockage.",
"Two things will happen. \n1. Water supply pressure will drop. If you have a high building, water could flow back to lower sinks by gravity. \n2. An air bubble will be trapped inside the sewer lines. Between the flush of floor 1 and the flushes of floors above. This air bubble wants to get out of the way. The air will take the easiest route, which could result in your toilet \"exploding\" or pushing all water back trough the sifon. The sifon is the j shape that prevents smells from leaving the sewer.\n\nWe used to have this problem with our toilet on heavy rain. All the water would storm its way down the sewer pipes. And since we were at the lower part of town, the air pushed away by the water would let our toilet \"explode\" the sifon contents on the ceiling.\n\nAn extra vent was placed in the streets to be the easiest path for the air. It has not happened since then.",
"This very test is done at large stadium venues before they open to the public. The Don and Mike radio show did a stunt at Jack Kent Cook stadium (now FedEx Field) where participants would poop in the toilets first.\n",
"Alright, \n\nSo, I was doing my Fire Inspector training and I was able to test this at a newly built NFL stadium about 4 years ago. We called it the \"Super bowl.\"\n\nWe recruited local Girl and Boy Scout organizations, schools, and had volunteers sign up to flush all the toilets in the stadium at exactly the same time. The purpose of this was to test the plumbing and simulating \"half-time\" when most attendees go to the restroom. As the local fire department we were assessing the stadiums ability to handle that much pressure loss. The reasoning is the sprinkler systems require a certain amount of pressure and we wanted to simulate the worst case scenario: Fire during half-time when everyone is busy flushing shit, literally. \n\nTldr; Fire department I was at did this at a NFL stadium being constructed. We had volunteers flush all the toilets as a stress test, called it the \"Super bowl.\" Nothing exploded.\n\nEdit: Inclusion. \n\nEdit 2: System we inspected was getting its water supply from a small body of water nearby. Our fire department was ensuring that this eco-friendly water system was capable of handling a heavy workload (bunch of flushing at same time) and still maintain enough pressure for fire sprinklers while being stressed. ",
"Nothing will happen, sewage pipe, fresh water pipes, chilled water pipes, goes through each individual systems, sewage pipes are not pressurized and by flushing you are just pushing water to the system nothing special.",
"There was an episode of Ahh Real Monsters about this exact thing. During Superbowl everyone shits and flushes at the same time and the monsters in the sewers use the sudden rush of water to do an annual race on. "
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2brmfx | the chomsky–schützenberger theorem | I tried reading the wikipedia article and was overwhelmed. I don't even know what formal language really is but I somehow stumbled upon this and now I really want to at least have an idea of what it is talking about, and **why it matters**. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2brmfx/eli5_the_chomskyschützenberger_theorem/ | {
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"EDIT: Phrasing on #2. Thanks, BassoonHero!\n\nHi, I'm a Compsci and Physics major at the California Institute of Technology. You're probably asking about the second (more famous/important) theorem, or the statement representing the context-free languages, or CFL's. Since this is ELI5, not AskScience, I'm going to keep things pretty simple and non-mathy.\n\nA \"language\", in computer science, is basically any pattern that can be put on a set of symbols. For example, the language L = 0* (read \"zero star\") is the set of strings consisting of any number of zeros. So the strings \"00\", \"000\", \"\", and \"000000\" would be in L, but the string \"010\" would not be. Similarly, the language L=0*10* is the language consisting of any number of zeros, followed by exactly one 1, followed by any number of zeros. For example, \"010\", \"1\", and \"100\" are all in L, but \"01001\" is not.\n\nLanguages are important because any function, such as \"square this number\", \"encode this\", or \"search for this element\" can be represented in a language. This is a very abstract concept, but just take my word on it for now, I don't want to get too complicated here.\n\nLanguages can be described in a few ways. Simple languages, like the ones I have given above, can be described by these things called [regular expressions](_URL_1_), which are basically logical operators applied to symbols. For example, \"01 ∪ 10\" accepts both the strings \"01\" and \"10\", but nothing else. There are other operators, but that's beside the point. Look up regular expressions if you're interested in these. Regular expressions are exactly equivalent to simple computing machines called [finite automata](_URL_0_), which can be thought of as flow charts you follow when receiving symbols. More complex languages, such as context-free languages (what you are asking about), and Turing-recognizable languages, require more complex machinery. \n\nThere are many different classes of languages, given by what type of machine they can be described by - the (major) classes are, in increasing order of complexity:\n\n* Regular languages - these are recognized by finite automata, which are basically flowcharts you follow\n* Context-free languages - these are recognized by pushdown automata, which are finite automata with RAM, in the form of a stack\n* Decidable languages - these can be solved by a Turing machine (which is basically a theoretical model of what your computer is) in a guaranteed finite amount of time\n* Recursively enumerable (Turing-recognizable) languages - these can be solved by a Turing machine in an infinite amount of time\n* Unrecognizable languages - these cannot be enumerated or spelled out at all by any classical computing model we have at the moment.\n\nAll of these languages, except the last, are subsets of each other. What this means is that any language that is regular (able to be solved for by a finite automata with no memory) will of course be context-free (able to be solved for by a finite automata with memory). Similarly, all CFL's are decidable, all decidable languages are recursively enumerable, etc.\n\nThe Chomsky-Schutzenberger Theorem is a theorem of equivalence for context free languages. In the simplest way possible, it establishes three conditions necessary to be a context free language. Every language that exhibits these free conditions will be a CFL, and every CFL will exhibit these three statements:\n\n1. The language is capable of accepting any string that consists of \"matching parentheses\", which we'll call P. This is very abstract, but what it essentially means is this: say you are given a language 0^n 1^n. This accepts all strings with equal numbers of 0's and 1's. The type of memory available to the finite automata is a stack, which is capable of counting a single value and decrementing it. In this way, it can count the 0's and then uncount the 1's. If there is nothing left on the stack at that point, there are equal numbers of 0's and 1's. However, it cannot read out the current number of 0's or 1's - it is a very limited memory type. The reason this is important is this: every CFL can be described in what is called \"Chomsky normal form\", which is basically a set of rules that take one type of substring, which we'll call A, and convert it into another two types of substring, which we'll call B and C, or into the empty string.\n\n2. There exists some regular language R over the language P. Bear in mind regular languages must be accepted by memoryless machines, so this is not a trivial statement. The language 0^n 1^n is context-free, but it is not regular - i.e. you need some amount of memory to keep track of the number of each digit.\n\n3. There exists a homomorphism (at at-least one way function between two things, i.e. f: a- > b. For example, f(x)=x^2 is a homomorphism because it maps x to x^2) between the matching parentheses language to the set of all strings such that the language in question, L, exists of this homomorphism applied to any string that is in the languages P or R. This is the most complicated part, but basically it says that any context-free language can be generated by applying some function to any string in P or R. This (very roughly) boils down to saying that a language is context free if it requires at most one value of memory that is required to be stored to spell out its contents.\n\nThis theorem is very similar to the theorem that any CFL can be put into [Chomsky normal form](_URL_2_), which I would recommend reading about first."
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e63f68 | how does frequency on a cpu impact performance? i.e. if i overclock a 2ghz cpu to 4ghz, is it +100% performance? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/e63f68/eli5_how_does_frequency_on_a_cpu_impact/ | {
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"Increasing the clock speed on a CPU increased the frequency with which it can process tasks. If you double its clock speed, that means it can send data through the bus twice as frequently.\n\nThis, however, does not translate to twice the overall speed of the computer. There are a number of other links to the chain that would bottleneck things (speed of your RAM, volume of RAM, speed of the other components within (GPU, SSD, etc), but in theory a task that relies 100% on the processing power of the CPU could be performed in half the time (think of highly complex mathematical calculations).\n\nBUT! Increasing the clock speed is not without consequence. Faster clock speeds generate more heat, and without effectively dissipating that heat (with a more efficient heat sink/fan configuration, or liquid cooling) that resultant heat will slow the machine back down. (hot wires have higher electrical resistance). If the components get TOO hot they'll actually stop working altogether, as the resistance gets too high for the circuit's integrity to be maintained (or it could result in physically damaging/destroying internal components like resistors, capacitors, melting solder points, etc.)\n\nGenerally overclocking your CPU is limited to a 5-15% increase, and is only done by enthusiasts who have invested in good heat management (a high conductive heatsink with push/pull fan setup, or liquid cooling.)\n\nIn short: heat is the enemy of performance in a computer, and increased clock speed, while results in increased performance, also results in increased heat which is bad. So it's a balancing act to get the most bang for your buck without shortening the life-span of the components themselves.\n\nEDIT: I accidentally a word",
"It would allow the CPU to do CPU things twice as fast.\n\nIt doesn't make your RAM twice as fast. It doesn't make your disk twice as fast. It doesn't make funny cat pictures download twice as fast.",
"No it’s not a linear increase like that.\n\nPersonally though I find clock speed to be the best indicator of performance apart from maybe benchmarks. Like others have said, a faster clock speed means that the CPU can process more instructions in less time. \n\nThere are other factors though like cache size (the more data you can hold in cache the less fetches you need to make from main memory - and fetches are very costly in terms of performance).\n\nAnother factor could be the instruction set being used, essentially you get simple instructions such as ADD which takes the values in 2 different registers, adds them and stores the result in a third register. We’re getting a bit outside my area of expertise now but let’s say the ADD instruction can be completed in a single clock cycle. \n\nNow lets imagine an instruction set which contains a multiply instruction which can complete in 2 clock cycles. And imagine we want to multiply 8x7. \n\nHow many ADD instructions does the first simple set need? Maybe 7. \n\nHow many MUL instructions does the more complex set need? Let’s say 1.\n\nIn these examples, we could say that a CPU with lower clock speed using the more complex instruction set might actually have better performance. To be clear, I’m not arguing that complex instruction sets are inherently superior, only in this made up example I’ve given.\n\nIn summary, it’s a balancing act, but for consumers I’d generally state that clock speed is a good indicator of performance.",
"Imagine if you could double the speed of your car. In an ideal world you could get to work/school in half the time. However, in the non-ideal, real world, there are things that prevent that such as speed laws and the other drivers that obey them. Even if other drivers don't observe speed laws your tires are likely not up to doing twice the legal speed limit all the time, Your engine will get hotter and the oil will break down faster. The answer is it will make your computer faster but things like hard drive access, reads and writes to RAM, video rendering etc. will all stand in the way of the ideal."
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86kioy | how do online passwords work/ protect information? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/86kioy/eli5_how_do_online_passwords_work_protect/ | {
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"Not very well, in most implementations.\n\nIdeally, your username should be an index into a database where a cryptographic hash of a salted password is stored. The salt is a per-user random string known only to the web application. This string plus the password you type are fed into the hash function, and the result is compared to your entry in the database. If they match, you \"know the password\" and can access the system. Salted passwords protect from the situation where some evildoer steals the whole password file, runs \"123456\" through the hash generator, and then looks at all the entries in the password file to find out who's password is \"123456\"."
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6xrjbb | economics behind smart grid technology? | Electricity price fluctuate throughout the day. Our meters don't show the price. With smart grid, our meters can inform us when the price is low so that we can use heavy equipments and charge cars, etc.
The question is, if everyone charges heavy appliances during low-cost hour, won't demand be increased and thereby increasing the price?
I don't know if I lack some information regarding smart grid or basics in economics. Thanks! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6xrjbb/eli5_economics_behind_smart_grid_technology/ | {
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" > The question is, if everyone charges heavy appliances during low-cost hour, won't demand be increased and thereby increasing the price?\n\nWhat it means is that demand will be leveled out. Yes it might increase the price up to standard, but it won't increase the price above standard to exorbitant which would have happened if people were charging during other than low consumption hours.\n\nThe economics aren't really the focus of the smart grid technology, the idea is based in trying to manipulate the public into making the operation of the power grid more efficient. When people consume more power than the usual methods of generation can manage they must switch to power generation which is faster to react but more costly, such as diesel/gasoline generators. On the same token the methods they use to fill baseline load like nuclear power or geothermal can be inconvenient or even impractical to quickly vary power output; nuclear power plants for example can take *days* to ramp up or down.\n\nSo they charge more when consumption is high and less when it is low in an effort to influence consumption into being more *stable*."
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1w3vih | why do many anarchists also consider themselves socialists despite the contradiction between the two ideas?? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1w3vih/eli5_why_do_many_anarchists_also_consider/ | {
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"It's not a contradiction. /r/libertariansocialism\n\n_URL_0_\n\n\"Libertarian socialism (sometimes called social anarchism or left-libertarianism) is a group of political philosophies that promote a non-hierarchical, non-bureaucratic society without private property in the means of production.\"",
"The myth that socialists are all statists is used by their critics to attack them. Socialism is a blanket term, meaning that there are many different kinds of socialism. Some are authoritarian, some democratic, and others libertarian. The main thing that ties socialists together is their opposition to private ownership of the means of production. They believe that there should be collective ownership. \n\nAs another poster noted, there is a form of socialism called libertarian socialism which favors limited government bureaucracy. A more extreme form of libertarian socialism is called anarcho-syndicalism, which favors a stateless collective society. Noam Chomsky is a well-known example of a person who holds these beliefs.\n\nMany libertarian socialists believe that right-wing libertarianism (e.g. Ron Paul) is not really libertarian because it only opposes government oppression without challenging oppression from the private sector. ",
"You should crosspost to /r/debateanarchism for a better discussion. ",
"23, 23 of them do."
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8glq1u | why cant movies and tv shows be on multiple streaming services like music is? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8glq1u/eli5_why_cant_movies_and_tv_shows_be_on_multiple/ | {
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"Licensing. The streaming service has paid a chunk of money to be the exclusive platform for the movie. You can have exclusive deals with a music provider, but In general, music is “get as many outlets to play my shit for the exposure”. ",
"They can be if the owner of the copyright chooses to sell it to multiple streaming services like the owners of copyright on songs do with their streaming services. But most streaming services for video negotiate to have exclusive streaming rights. ",
"They can, many are, some have exclusivity deals. At one point It's Always Sunny for example was on Hulu, Netflix, and Amazon at the same time. Now it's not on Amazon certainly and unsure about the others."
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1qtjok | why have cities stopped changing their appearance? | In Los Angeles, the city's buildings, homes, etc are mostly from 1910s to 1970s. There's hardly any buildings or homes in Los Angeles that were built in the 2000s. Why is this? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1qtjok/eli5why_have_cities_stopped_changing_their/ | {
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"Replacing buildings is expensive, you can't tear a city down every year to give it a \"new look\".\n\nIf there are hardly any 2000s buildings in LA then that means there was hardly anything built there then, most likely because the current buildings satisfied all their needs.",
"What other people say are correct. The other reason is that in LA particularly, regulations like rent control make it very difficult to make a profit while renting to people, and so new housing is not built. You also have things like restrictions on building heights in many areas which again make it harder to make it worthwhile to replace older buildings by newer buildings."
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229k8n | what makes welding so difficult? what makes someone a good welder? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/229k8n/eli5_what_makes_welding_so_difficult_what_makes/ | {
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"There are several different types of welding, and they vary in difficulty. Mostly, the problem is that the machine doesn't automate the process as much as you might think; the operator needs to control angle, speed, distance from workpiece, and so on. Many of the variables affect other variables, and it takes some experience to set up the work correctly. Gas-shielded welding, where a flow of inert gas protects the weld site from the surrounding air, can be affected by wind or air currents. Welding dissimilar materials can be much harder or even impossible, depending on dimensions, metal type, and method of welding. Orientation of the pieces is relevant; welding over your own head can be tough. Preparing the piece is crucial; it must be clean and well-fitted before you even begin. Being a good welder takes 1. Decent equipment 2. Well-prepared work and, most importantly, 3. Practice, practice, practice, practice."
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1vd0xr | why can't we use a balloon like the red bull space jump to get into space and then a smaller amount of fuel to get into space, rather than a rocket? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1vd0xr/eli5_why_cant_we_use_a_balloon_like_the_red_bull/ | {
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"A balloon like that only works if it isn't carrying very much. And the balloon only gets you stationery in the air. If you want to orbit the earth or go to another planet you still need TONS of energy to get away from ~~the pull of~~ the earth, or to get into orbit. That still requires a lot of fuel, which is a lot of weight, which wouldn't work with a balloon.\n\nEdit - Correction, you can't get way from the pull of the earth. I meant to say get further away then the balloon alone could bring you, not escape the force of gravity",
"To orbit the earth you have to do 2 things, \n1) get far away from it\n2) move really fast, so fast that as you fall towards earth you miss. This is orbiting. \n\nYou are still pulled towards earths gravity when you are orbiting it. when orbiting, you are basically falling to earth but missing because you are moving so fast. THe balloon space jumper was mot moving very fast so he didn't miss the earth and came down.",
"just comparatively. the red bull balloon was at 128,000ft or 39km. the ISS station is at 370km. ",
" \"The reason it's hard to get to orbit isn't that space is high up.\nIt's hard to get to orbit because you have to go so fast.\"\n\nXKCD's \"What if\" has a good explanation on why this doesn't work.\n \n_URL_0_\n\n",
"Great responses. How does this fit in with the idea of the \"space elevator\"?",
"What you want is an [Inflatable Space Tower](_URL_0_). \n\nWell, it can be rigid instead of inflatable to perform the function, but if you can build a tower light enough and strong enough (and this would be mega-engineering on a mountaintop), you can pressurize the inside (to sea-level pressure, or maybe higher), float your spacecraft up 20 miles (after somehow getting the spaceship to the mountaintop... hmm), and then fire it away. 20 miles of free lift would still represent a substantial energy savings (well, 10-20% at most) over ground-launch: rocket engines are incrementally more efficient when there's less atmosphere (think of the thrust pushing against the air as it exits the nozzle), and you'd save a lot of fuel just because you'd spend less time climbing on your rocket engines. \n\nIf you read that article, you can see the reference to David Brin's 1980 book *Sundiver*, which alluded to a pair of such towers, called the Chocolate Needle and Vanilla Needle, which worked in this fashion. *Sundiver* is the first novel of the *Uplift* universe.",
"Play a game called Kerbal Space Program. It's surprisingly realistic",
"Gotta have forward speed. When in orbit you are actually in free fall. You are just moving forward fast enough that the earth is curving away from you at the same rate you are \"falling\"."
]
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| [
[],
[],
[],
[
"http://what-if.xkcd.com/58/"
],
[],
[
"http://www.space.com/6867-inflatable-space-tower-proposed.html"
],
[],
[]
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|
||
a24iit | why is it so painful to accidentally bite your own tongue but when you purposefully bite it, it doesn’t feel like anything? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a24iit/eli5_why_is_it_so_painful_to_accidentally_bite/ | {
"a_id": [
"eav1i60",
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"score": [
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"text": [
"The reason is because when you bite down on your tongue on purpose, you aren’t actually biting down as hard as when you bite on your tongue accidentally.\n\nYour brain knows you are about to hurt yourself, so even if you don’t realize it, when you bite down on your tongue on purpose, you aren’t biting down as hard.\n\nIt’s that simple.",
"When you accidentally do it you bite it like it's a piece of meat you're trying to get through and you typically only catch the tip of it.\n\n\nWhen you purposefully do it you will (most people anyway) struggle to bite with the same amount of pressure. You're more likely to build up the pressure and stop at a point that feels firm but isn't enough to properly hurt. I suspect it's just difficult to purposefully bite your tongue properly hard.\n\n\nSame sort of thing happens if you drive manual in a car if you accidentally use your left foot for braking. Your foot is so used to pushing down on the clutch that when you press the brakes you slam all on all rather than just gently apply it like you would with your right foot. This happens even when you purposefully use your left foot to brake (at least the first few times until you get used to doing it...not that I recommend being a left-foot braker).",
"Not a direct response, but what is a typical human bite force? I imagine it will be quite difficult achieving that consciously. As we chew though, chewing being semi-autonomous, the full force of our bite can be exerted when our tongue gets in the way. \n\nA more interesting question will be, what exactly makes our tongue go out of sync with our teeth such that it gets in the way of the lower jaw as we chew? "
]
} | []
| []
| [
[],
[],
[]
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|
||
14lclu | the questions raised by today's xkcd. | Why is the sky blue instead of Violet?
And why is it that when we look in a mirror, we're flipped horizontally, but not vertically?
[Here's the comic.](_URL_0_) | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/14lclu/the_questions_raised_by_todays_xkcd/ | {
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"c7e4knm",
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],
"score": [
8,
10,
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"text": [
"[Here's sunlight scattering, explained like you're 5.](_URL_0_)",
"[Here's Feynman explaining the mirror problem](_URL_0_).",
"Basically things in a mirror aren't flipped horizontally. The left side is still on the left as the upper side is still on top.\n\nIf you now try to mention a book/piece of paper/word as an example, I have to disappoint you, because this depends totally on the axis you flip it."
]
} | []
| [
"http://xkcd.com/1145/"
]
| [
[
"http://www.youtube.com/watch?v=oZPiyEZgc2s"
],
[
"http://www.youtube.com/watch?gl=CA&v=msN87y-iEx0"
],
[]
]
|
|
bbuokd | what distinguishes dolphins from other toothed whales? | I keep finding stuff about how orcas are the largest dolphin, but when I try to research dolphins, it just says they're toothed whales. Some sites even imply that all toothed whales are dolphins. In that case, why isn't the sperm whale considered a dolphin? What makes dolphins different from other toothed whales? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bbuokd/eli5_what_distinguishes_dolphins_from_other/ | {
"a_id": [
"ekm475p"
],
"score": [
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"text": [
"Taxonomy is a mess. Initially, all names were given by people who didn't know about phylogeny (study of evolutionary links between species, ie the only rigorous way to classify animals): it means their are based on wacky criteria. \n\nDolphins are marine mammals with teeth and a certain \"shape\". That means some animals (beaked whales, porpoises, belugas...) were arbitrarly excluded from the family: there is no magical characteristic that they lack (they have the same common ancestor as all dolphins), but it has been decided they are not dolphins.\n\n & #x200B;\n\nGo to the wikipedia page of \"Cetaceans\" and look at the tree in the \"taxonomy\" section. The tree gives you the phylogeny of cetaceans, and you will see that the branch \"toothed whales\" contains all dolphins plus a few other animals.\n\n & #x200B;\n\nTl;dr: Dolphins share a common ancestor, but arbitrarly exclude a few animals This taxon is said to be **parphyletic.**"
]
} | []
| []
| [
[]
]
|
|
5stnjg | why do things get slower the bigger they get? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5stnjg/eli5_why_do_things_get_slower_the_bigger_they_get/ | {
"a_id": [
"ddhpj5j"
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"score": [
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"text": [
"Muscles are most efficient when they are small. There is also a law that says when size increases, the volume of the creature increases by a factor of x^3 but the muscles only increase in strength by a factor of x^2. So whilst elephants and whales are much stronger than humans, pound for pound they are much weaker because they have to deal with so much more mass. "
]
} | []
| []
| [
[]
]
|
||
b2d4h6 | how do other animals see light from lightbulbs? | If you record a video in a room where the lights are on and you slow down the video, you'll see the lights start blinking on and off. Are there other animals that see this normally, and if so what are they? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b2d4h6/eli5_how_do_other_animals_see_light_from/ | {
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"eirxltr",
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6
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"text": [
"~~Argh, there's a phrase for it. It's not phase continuity, but it's something similar.~~ **Flicker fusion.** The idea is that your brain/eye blends quick flashes into a single beam after a certain threshold.\n\nAnd here we probably just have a currently unanswered question. There's no reason to think that this threshold is the same for all brains or animals, but there's not really any evidence off the top of my head of any differences.",
"I believe pigeons can perceive fast flashes as separate. Supposedly they wouldn't see a normal cinema film as continuous motion but a series of stop-motion frames much as we would see normal movement under a strobe light.\n\nEdit - here's a link to it\n\n_URL_0_"
]
} | []
| []
| [
[],
[
"https://www.psychologytoday.com/gb/blog/what-shapes-film/201406/why-you-can-t-take-pigeon-the-movies"
]
]
|
|
b77ut3 | why are americans called yanks (by foreigners) in so many movies? who are the yanks/yankees? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b77ut3/eli5_why_are_americans_called_yanks_by_foreigners/ | {
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"text": [
"There are a lot of competing theories about the etymology, but essentially it was a word that originated early in the history of the country to describe what would become Americans. It's just sort of a slang word, like Brit, Ozzie, or Canuck or anything like that.\n\nIt's an old enough word by now so it has kind of a lot of different meanings to different people. \n\nBasically it's just a word for \"American\" and depending on who's saying it, it's either an insult or patriotic or friendly."
]
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| []
| [
[]
]
|
||
64bwzt | why are they replacing the a-f system in the uk? with "levels"? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/64bwzt/eli5_why_are_they_replacing_the_af_system_in_the/ | {
"a_id": [
"dg0you1"
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"score": [
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"text": [
"I think the reasoning is that they can add new grades to the newer system more easily.\n\nWhen I was at school, the highest grade you could get was an A. Then they introduced A*. Now they want something better than an A*, but A** is just silly, and what will they add after that?\n\nWith the new system, they've been able to set it so a 9 is slightly harder to get than an old A*. And they can easily at a 10 or an 11 in future."
]
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| []
| [
[]
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|
||
fv8016 | how are the sights on guns calculated and made to be accurate? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fv8016/eli5_how_are_the_sights_on_guns_calculated_and/ | {
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"text": [
"They're not. You see where the bullet hits when you fire the gun, and then you adjust the sights until they point at where you hit. No joke. \n\nIt has to be this way because everything depends on how you hold it. Different people hold the weapon differently and so the angles will be slightly different. \n\nWhen I was in the Army, it was called \"zeroing\" your rifle. You would aim at the bullseye and shoot at a target until all your bullets were going the same place, and then adjust the sights, and then do it again, over and over until your bullets were hitting the bullseye. There's dials to set to different settings. In theory, once you had your rifle zeroed, you could use those dials to account for elevation, range, and wind, but as tankers we never got training on that aspect. \n\nPrecision sighting is much less important in pistols because the effective range is much shorter, but it's the same for them. There's screws so you can loosen and move the sight posts slightly and then tighten them down again."
]
} | []
| []
| [
[]
]
|
|
7ntb37 | the science behind supercooling? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7ntb37/eli5_the_science_behind_supercooling/ | {
"a_id": [
"ds4lx93"
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"score": [
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"text": [
"Ice crystals are like a tree that needs dirt to grow out of. If there's a container of pure water, it's supposed to grow ice but there's no dirt to grow out of so it just sits there confused until something happens to it. "
]
} | []
| []
| [
[]
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|
||
an9dl4 | why does sleep help you recover from illness? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/an9dl4/eli5_why_does_sleep_help_you_recover_from_illness/ | {
"a_id": [
"efrqxal",
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"text": [
"The less your body has to deal with things while trying to fight off an infection, the better. Things like physical exertion, mental and emotional stresses, and just daily activity divert some of the body's resources away from the immune system. \n\nWhen you sleep, pretty much everything gets set to \"low power mode\" so your body can focus maximum effort on recovery, and when the immune system is challenged, that makes a big difference.",
"About 75% of Growth Hormone is released during sleep, according to experts, which aids recovery and repairs damage caused by illness and exercise. Your heart rate decreases to around 40 bpm compared to 60 when awake, saving energy. Your brains also rests comparatively, but during deep sleep it can spike in activity. Your also not moving as much as normal saving more energy. All this saved energy goes into helping you get better, also sleep makes time pass in an instance so instead of 8 hours feeling crummy while awake, you wake up 8 hours more repaired.",
"You're also (and this is important) **Not Subjecting your immune system to new, and different stressors** with your decreased activity.\n\n & #x200B;\n\nImagine it as a point buy system. You generate 100 points per hour.\n\n* Operating Cost(Heart beating, steady breathing) is 10 points/hour. **You must buy this.**\n* Immune response is 5/Hour Per foreign material type(I.E. Pneumonia is independant of say, herpes, or swine flu.)\n* Physical motion is 15/Hour\n* Separation and digestion of ingested materials is 10/hour\n* Mental Stress is 25/hour\n* Physical stress is 30/hour\n\nBuying each of those things at 1 point per hour spends 95 points per hour. Now when your sleeping normally, you can discount 70 points worth, and buy heavy into immune response.\n\n & #x200B;\n\nThe more you sleep, the more you can buy into immune response, by \"Sacrificing\" points you'd spend on things like.. Getting pizza(Physical motion, Digestion) with your peer group(Mental stress) and that girl you kind like(More Mental stress), One of the peer group may also have their own sickness which you could be exposed to(which is then a second Immune response cost).\n\n & #x200B;\n\nSource: D & D Nerd."
]
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| []
| [
[],
[],
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|
||
1nvei1 | why could homosexuality be considered wrong? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1nvei1/eli5_why_could_homosexuality_be_considered_wrong/ | {
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"text": [
"lack of understanding, ignorance, bigotry, or even being told it is wrong by authority figures.",
"Because you can't reproduce. Therefor it is against nature...not saying I agree. ",
"From a basic evolutionary position, our only role on this rock is to have offspring. This is pre-programmed into us at a deep level. Everything we do is geared up to fulfil this function. \n\nTo most straight people, the idea of a dude finding another dude sexy is odd. It is perfectly normal to feel this way, it is odd to see people who are going against what is, in a straight person anyway, something deeply coded inside of us to want to reproduce.\n\nThose who want to be haters will pray on that concept of 'this is odd' and turn it into fear, hate and they will say it is wrong. They will do this because they see gay folk as being different to them with such a fundamental thing and they cannot understand it, so as /u/RandomExces said, it turns into ignorance and bigotry. It is very easy to turn the perfectly normal thought of thinking its odd that a dude likes another dude, into saying its wrong and that these people are wired wrong and blah blah, pack mentality kicks in and idiots follow this bs and it ends up as hate. Humans are pack animals, we will generally follow the crowd and its easy to single out those that are different rather than being rational about it. Throw in a few hundred years of bigotry and ignorance and thats how you get to idiots being irrational and saying its wrong to like other dudes. \n\nTLDR: Most straight people are pre-wired to reproduce. Gay people are not. Straight people think thats a bit odd and then idiots who don't understand and who want the whole world to be the same say its wrong and it soon escalates to hate.",
"A lot of people confuse \"different\" with \"wrong\". There's not really much more to it that that. ",
"I wasn't seeing answers here about *why* homosexuality would be considered wrong by someone...\n\nIf you believe that there is a moral law, that is, a law or set of rules set by a higher authority, then things that break that law are considered wrong.\n\nSo, simply enough, people whose belief system includes the moral law forbidding homosexuality would consider it wrong. "
]
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| []
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[],
[],
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|
||
7dynou | why do we get those weird wrinkles/lines on our faces or body after sleeping? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7dynou/eli5_why_do_we_get_those_weird_wrinkleslines_on/ | {
"a_id": [
"dq1aaz5"
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"score": [
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"text": [
"The skin was pressed against a fold or wrinkle of fabric which created a lump, which in turn caused a temporary indentation in your skin. This happens after sleeping because you don't move for a long time, but could just as easily occur while awake if you didn't move."
]
} | []
| []
| [
[]
]
|
||
agbv6t | what does it mean “feels like” when they talk about weather? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/agbv6t/eli5_what_does_it_mean_feels_like_when_they_talk/ | {
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"ee50q8d",
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"text": [
"The air temp is actually 3 degrees, but wind blows it or the air is moist so it feels like -3 degrees when it hits your skin",
"The real temperature doesn't necessarily account for the wind chill. The \"feels like\" temp considers how cold it would feel like to a human since the wind is blowing.",
"It feels like -3 because of wind chill.\n\nThe actual ambient temperature is 3 degrees, but when wind hits your skin, the air molecules are slightly heated by your body, and are then blown away. This speeds up the rate of body heat loss from your body, thus causing you to cool down quickly, which is why it feels cold"
]
} | []
| []
| [
[],
[],
[]
]
|
||
51w3mt | why are time measurement units ordered by 6 and not by 10? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/51w3mt/eli5_why_are_time_measurement_units_ordered_by_6/ | {
"a_id": [
"d7fd93j",
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"score": [
3,
3
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"text": [
"The west (Europe/Mediterranean) was originally based in a duodecimal (12) system of counting, the decimal (10) system came later from Persia. \n\nThe Babylonians made astronomical calculations in the sexagesimal (60) system.\n\nNow, the Egyptians invented the sundial to be able to divide the day up in to parts accurately, they divided it into 12. But this was before minutes could be measured accurately, so hours were divided into quarters. Then, the Greeks used the Babylonian system to create a 'compass' or basically a way to record direction, based on the sexagesimal system. When minutes could be recorded, with the advent of mechanical clocks in the middle ages, people based the clock face on the Greek compass, i'm not sure why, but that is why there are 60 minutes in an hour.\n\nSource: History class ",
"Another thing to note is that 60 is the smallest number that is divisible by 2, 3, 4, and 5 (and by 6 and 10). "
]
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| []
| [
[],
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|
||
c6vof4 | how does a tax war on imports between 2 countries affect the rest of the world ? | With the recent incidents about both China and the USA imposing huge tariffs on imports from their counterparts, how does this affect the rest of the world ? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/c6vof4/eli5_how_does_a_tax_war_on_imports_between_2/ | {
"a_id": [
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"text": [
"OMG! I am mad at Ashley, I don't want to talk to her. Hey Karen, I am mad at Ashley and if you talk to her, we aren't friends!\n\nHey! Did you hear that Nat is being a bitch to Ashley? What happened? Anyways, whose side should we pick? Cause ultimately we have to pick a side, otherwise I don't want to be in one of their bad side. Nat hooked me up with this hot dude and I don't want her telling some weird stuff to him about me. But, Ashley totally throws awesome parties and I want to make sure that if this thing with Nat doesn't work out, I have some back up boys!!! I wonder what Karen is doing.\n\nEdit: this is why tariffs are stupid!",
"The clearest and most direct impact is that it shifts the pattern of global trade. China makes goods and exports them to the US. But most often, China isn't the sole producer of such goods. Other countries like Mexico, Vietnam etc may make the same goods and also export them to the US. With the tariff, buyers may prefer to buy more from those countries not affected by tariffs and less from China.\n\nThe second less direct impact is that many goods go through may different stages in different countries in the course of their production. The simplest example is while China might make a lot of rubber soled shoes, most of the rubber used is probably imported from Brazil, Indonesia or Malaysia. (China doesn't/cannot grow rubber trees) If the tariff reduces demand for Chinese shoes, then there will also be less demand for the rubber which then impacts those other countries.\n\nThe third issue is spending pattern. If say China is the sole producer of product X that is widely sold in the US. If tariffs increase the price of X in the US, this means that people who want or need X will have to spend a larger percentage of their income on X, this means that they have less income/money to spend on other things. A simple (fictional) example: If China produces a lot of food and a tariff is imposed on that food. Since people still need to eat, they will have to pay a higher price for their food, which means they have to spend less on going to the movies, or holidays etc."
]
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[],
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|
fcy2b7 | why exactly were open wounds more dangerous ages ago, then the wounds today even without medical treatment? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fcy2b7/eli5_why_exactly_were_open_wounds_more_dangerous/ | {
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" > I mean back then it was literaly a deathscentence if you fall down in the grass and get a tiny open wound on your knee by a rock in the grass\n\nSo I don't think this is necessarily true. Large, severe cuts were prone to infection back then just as they are now, but if people died from small cuts on their knees or hands we would have never survived past the primal stage. The human body is good at fighting regular, everyday infections. The problems you had in the past were with more major injuries - amputations (which they did a lot more of because of lack of other treatments), stab and gunshot wounds, broken bones etc.\n\nBasically, the world didn't get any less bacteria-filled or dangerous, you just see fewer infection related deaths because (1) we've learned to keep things in the medical sphere clean, and (2) because we have antibiotics. Any small wound infection that would have landed you in the grave 100 years ago would still land you in the hospital today, you just wouldn't die from it",
"Tiny cuts rarely would kill people. It was more the moderate injuries, and burns, that were prone to infection. The body can close small cuts fairly quickly on it's own, by sealing it with a scab. This helps prevent infection naturally. \n\nWhen a wound is exposed for a long time because it is large, that's when infections have a better chance to set in. Without proper medicine, they would have a near impossible time getting rid of the infection once started. A bandage creates a seal to keep infections out while the body tries to fix it. Stitches pull the wound together to speed the process. \n\nNow of course, we also have medicines which can kill the infection. Or in worst cases, we can amputate the infected limb to stop it from spreading to other areas.",
"You have some major misconceptions that need to be cleared up. It was never \"literaly \\[sic\\] a deathscentence \\[sic\\] if you fall down in the grass and get a tiny open wound\". That's absurd. People get cuts and scrapes and minor woulds all the time. 99.9999% of the time, the body more than capable of handling any bacteria that enter the body through these small wounds. Even more moderate infections that we commonly take antibiotics for now our bodies can get rid of on their own. Antibiotics just speed recovery and make us feel better faster. Our bodies are quite good at handling everyday infections. That's why we have immune systems.\n\nAs for your claim that the same wounds used to be more dangerous without medical treatment, that really makes no sense. A compound fracture 100 years ago was exactly as serious as a compound fracture today. The difference *is* medical treatment that we have now and didn't have back then. That, and our understanding of the role of hygiene in preventing infection."
]
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| []
| [
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|
||
d3j2d5 | why do douchey cars make that loud popping noise when they downshift? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/d3j2d5/eli5_why_do_douchey_cars_make_that_loud_popping/ | {
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"text": [
"The popping sound is likely unused fuel igniting in the exhaust. The “fooosh” noise is from the turbo releasing unneeded pressure. \n\nWhy would you put a rear wing on a front wheel drive car?",
"It’s often added or amplified after the stock version. A lot of people like the popping, and think it makes the car sound nice and cool."
]
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| [
[],
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|
||
9vq9qq | how is the federal budget calculated in the usa? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9vq9qq/eli5_how_is_the_federal_budget_calculated_in_the/ | {
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"text": [
"There is a budget set by the House, allocating spending to thousands of different \"program elements\". These spending bills are passed by the House, and the Senate, and then signed by the President. Each PE is assigned to a government office, and they spend the money.\n\nAlas, the taxes are set in different legislation. Sometimes this leads to a balanced budget, where the government brings in exactly as much as it spends. OK, that never really happens. Sometimes there is a surplus, where the government brings in more than it spends, and sometimes there is a deficit, where the government spends more than it brings in (Usually This)."
]
} | []
| []
| [
[]
]
|
||
2ixtmp | why doesn't quantum entanglement regard as breaking the speed of light? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ixtmp/eli5_why_doesnt_quantum_entanglement_regard_as/ | {
"a_id": [
"cl6gxuh"
],
"score": [
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"text": [
"Because there is not travel as far as I know, it is just the relationship of two particles"
]
} | []
| []
| [
[]
]
|
||
2b8nnq | what would the objective economic effects be if the united states allowed immigrants to freely come, work, and pay taxes? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2b8nnq/eli5_what_would_the_objective_economic_effects_be/ | {
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"OK let's assume a massive influx of new immigrants into the U.S. above what is already going on. Like, 2,3,4,5 times as many. At least.\n\nConsidering there is already a 6% unemployment rate in the U.S., you'd need to find jobs for these people. Which means you would need to create jobs through public works projects, or just hope existing business owners would open their arms to the idea and start hiring people. Let's assume that non-English-speaking immigrants would take low-tier jobs like landscaping, labor, house-cleaning, etc.. You'd need to expect the current suburban homeowner to *want* to hire them. If these people don't get jobs, you just need to give them money (i.e., welfare) or watch them starve and become homeless.\n\nAssume you've given them jobs, now where will they live? (Detroit, you might say, lol). Seriously, they won't all go to Detroit, because immigrants currently exist *everywhere* in this country, from L.A. to NY. This might solve the above-mentioned problem - they could be paid to build their own houses. Where's the money going to come from, though? Tax-payer dollars. Good luck getting your parents, who already struggle to pay property tax on their re-mortgaged home, to want to shell out more.\n\nNext, education, which is already a hot-button issue for existing illegal immigrants. You want these new immigrants to assimilate and become a part of the system. So now you need to start packing them into already over-filled classrooms and hire a bunch of new ESL teachers, a part of their education which will leave them already behind the native English speakers that already live here. So what you've bred is a bunch of disenfranchised new citizens who can't compete in whatever kind of crappy job market already exists here. Tell me that won't lead to crime problems.\n\nWho knows, maybe 10 years down the line everyone will have assimilated and the country would be a better place for it. But for a while, it would be a clusterfuck.",
"There's a lot of research on the subject with differing conclusions all around, and because it's so controversial, people always accuse the researchers of bias. Some say that it would be a net positive for the U.S. Immigrants, like anyone else, need food, housing, and other commodities, and by buying them here, they grow our local economy, which means more jobs total. Also, any new workers and consumers (be they immigrants or homeborn citizens) means more tax revenue for local, state, and federal governments.\nOn the other hand, low-income people in general (as most immigrants are) are a burden on government budgets, because they consume more in government services than they pay in taxes. Also, an influx of unskilled labor means generally more competition for scarce employment, which not only makes it harder for people to get hired, it also makes wages lower.\n\nNow, all those things I listed are what happens, objectively. The argument is over the extent to which they happen. Will the economic growth they cause generate more jobs than they took just by coming here? Will the new tax revenue they pay into governments balance out with all the services they will require?\n\nBut again, that's all just from an economic standpoint. We also have to consider other arguments for and against allowing immigration. It's not all about money. For one, America has something of a responsibility for these immigrants, since our government's actions are a major factor in creating the negative environments that make a lot of Central American immigrants want to come here in the first place. Our war on drugs is directly responsible for the out of control cartel and gang violence in Mexico and El Salvador. And the U.S. supported a military coup in Honduras in 2009 which has further destabilized the situation for poor people in the region. Also, a lot of the \"Free Trade\" agreements America pushed for like NAFTA are responsible for decimating the Mexican economy, depressing wages and eliminating jobs in Mexico.\n\nFurther, the strict border policy we have today is unprecedented historically. Up until the 1980s, the US-Mexico border was highly fluid, and Mexicans moved freely back and forth to work and live in America. And we had no problem with it because American companies could pay them low wages. Also, America basically stole half of Mexico's land way back in 1848. All of what is today California, Nevada, Arizona, Utah, and New Mexico, was forcibly taken from Mexico after the brutal Mexican-American war, which America deceitfully instigated. Is it fair to take their land and then deny them and their descendants the right to even live on it?\n\nFURTHERMORE, there's a human rights component. The U.N. recognizes the right to free movement as an inalienable civil right. People should have the right to move and live where they wish. And a lot of these immigrants are sick and starving, and in considerable danger in their home countries. In the US we provide healthcare and food stamps to those too poor to afford them for themselves, and we have a justice system that (in theory) protects people from crime and violence. Some would argue that it's unfair, even racist, to say that only people living on one side of an arbitrary line on a map deserve these things, and the people on the other side should be left to rot. ",
"Well first we'd look at what happened when this was the case in the US. The United States had more or less unrestricted immigration from the time of independence to the 1920s. A few constraints were put in place until something close to what we have today developed in the 1950s/1960s, barring a few exceptions such as war and the [Chinese exclusion act.](_URL_0_) \n\nCertainly this allowed for relatively fast population growth. Our large immigrant groups, such as Irish and Italian Americans came during the unlimited immigration periods. There were complicated cultural issues and problems brought by the new migrants which, as we know, were solved in time. Ultimately our country was better off, though the people living through that period may beg to differ.\n\nAlso, it's interesting to remember that the unlimited immigration period also applied to Mexican citizens as well. While we focus much of our attention on them, **Mexican citizens had no restrictions on their ability to immigrate until [1965](_URL_1_)** \n\nThere is a theory that much of the illegal immigration we experience now is due to closed borders, that is people work harder to cross in fear that it will become more difficult to get in later, and that they won't leave because they fear they won't be able to return.\n\nThe reality is, your question is not a hypothetical, it was the reality for much of all human history except for the 1960s on. This period of tightly controlled immigration is the experiment. And it's not working out particularly well. It attempts to control the supply and demand of labor in a way which is unnatural.\n\nConsider the fact that immigration is unrestricted from state to state. We'd assume that people would desperately flock from poor West Virginia and Mississippi to rich New Jersey and Maryland. That's not really the case, but the situation would be different if west Virginians suddenly believed that their ability to moved into New Jersey would soon be curtailed. "
]
} | []
| []
| [
[],
[],
[
"http://en.m.wikipedia.org/wiki/Chinese_Exclusion_Act",
"http://en.m.wikipedia.org/wiki/Immigration_and_Nationality_Act_of_1965"
]
]
|
||
66sqgc | barometric pressure and how it affects the weather. or, if it's just an indicator of impending weather, how does it work? | Bonus points for helping me understand the difference between dewpoint and humidity and what they really mean. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/66sqgc/eli5_barometric_pressure_and_how_it_affects_the/ | {
"a_id": [
"dgl0wzg"
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"text": [
"Ok, here goes. So, \"barometric pressure\" is simply a fancy way of saying \"air pressure\". It's measured in either inches of mercury (how far mercury can be driven up a J-shaped tube with a vacuum at one end and open at the other) or hectopascals, which is the SI unit for air pressure. Air pressure is a result of the weight of all the air above you in the atmosphere, much like the pressure at the bottom of the ocean is a result of the weight of the water. It is driven by two things, weather systems and temperature. The influence of temperature is pretty simple: warm air is less dense and tends to rise, reducing pressure at the surface because the air weighs less. Cold air is dense and tends to move downward in the atmosphere, creating more pressure at the surface. But weather systems are the main factor driving air pressure. High pressure systems move down from the north (or up from the south in the southern hemisphere) and push into regions of warmer, moister air, forcing that air up the leading edge of the colder mass of air, exactly like a bulldozer blade. This is a cold front. As the front lifts the air ahead of it, clouds form (air cools as it gets higher in the atmosphere because it decompresses with altitude) and you get rain, storms, etc. This lifting effect is why pressure drops before a storm, also because storms themselves suck air up and away from the ground. \n\nSo you can see that weather mostly controls pressure, and not the other way around. It's a side effect of the weight of the atmosphere. Pressure does have one major effect, though, and that's wind. Wind is the equalization of pressure differences across the surface of the earth, somewhat like air rushing out of a balloon until the pressure is equalized. \n\nAs far as dew point and humidity is concerned: Humidity is simply how much water vapor is dissolved into the rest of the air. The atmosphere can only ever contain 4% water vapor, any more and it becomes saturated, causing the water to condense out as dew or clouds, or frost if the air is cold enough. Dew point isn't actually an objective measurement, but instead a calculation. It's just the temperature you would have to cool the atmosphere to in order to reach saturation. Therefore, the temperature can never be less than the dewpoint, only more than or equal to it."
]
} | []
| []
| [
[]
]
|
|
43x61i | why can self harm be addictive? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/43x61i/eli5_why_can_self_harm_be_addictive/ | {
"a_id": [
"czlpqn6"
],
"score": [
2
],
"text": [
"Endorphins (body's natural pain killer which opiates replicate), adrenaline, and the emotional release which are experienced during and after self harm are addictive."
]
} | []
| []
| [
[]
]
|
|
3zxadr | how can someone have an object penetrate their skull and brain and still live? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3zxadr/eli5_how_can_someone_have_an_object_penetrate/ | {
"a_id": [
"cypqh27",
"cypqpti"
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"score": [
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3
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"text": [
"The skull isn't that important. I mean it's really just there to protect everything and give shape to the head. So let's ignore penetration of the skull. \n\nThe thing that matters here is the brain. And the brain is a very complex organ that has many specialized areas for certain types of processing and some redundancy. To a certain degree the left hemisphere can do whatever the right hemisphere does (and vice versa). \n\nSo if something kills a part of your brain that 1) isn't required for survival (like regulating your heartbeat) or 2) the rest of your brain can take over, like the other hemisphere or areas nearby, then you'll live. \n\nDepending on what area of the brain is damaged, your life may be quite different though. If something damages your occipital lobe, you may be blind. In the case of Phineas Gage who had some steal shoot through his skull, it seems it interfered with some of his personality (maybe emotional processing). \n\nFinally, if it happens when you're young, neural plasticity is very high. That means your brain is very adaptive at this stage and different areas can easily compensate for the damage by doing more work. Some children can live with only one hemisphere! Sure, maybe their total intelligence won't ever be genius level, but they more or less are of average or below average intelligence. Adults brains are plastic, too, but just less than children.",
"It depends on what part of the brain was damaged and to what extent. Not all bits are used just for mere survival."
]
} | []
| []
| [
[],
[]
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|
||
69rtjh | invention of soap came way before germ theory (right?). so what were they actually thinking? a happy accident? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/69rtjh/eli5_invention_of_soap_came_way_before_germ/ | {
"a_id": [
"dh8ur4h",
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"text": [
"When humans grubbed about in the dirt and mud, we got dirty. Often times sticky liquids used to fall on us, like sap or blood. \n\nNormal water in the rivers was enough to wash ourselves of dirt and blood, but humans noticed that fats helped in removing these sticky resins from our skin. \n\nThat was the early precursor to soap and from there humanity basically used it as a way to keep ourselves clean of macroscopic things rather than as antibacterial as its used today (not good imo)",
"Mercifully, there's some overlap between the vague sense people and cultures have long had of dirtiness/uncleanliness, and the actual risk of pathogens. (As a species, we've been staying away from poopy water far longer than we've known about *Vibrio cholerae* or *Salmonella typhi*.) Soap is indeed thousands of years old, and has always valuable for cleaning greasy and dirty stuff that water alone won't dissolve, whether clothing or skin."
]
} | []
| []
| [
[],
[]
]
|
||
35aai6 | if 60%+ of us citizens want marijuana legalized, why hasn't it been? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/35aai6/eli5_if_60_of_us_citizens_want_marijuana/ | {
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"Because the legislature of the United States is not structured such that it immediately responds to popular demands. And we should be glad it doesn't.\n\nWho says 60+% of citizens want marijuana legalized? A magazine? A news paper? A television show? How did they arrive at that statistic? What was the sample size? Its demographic make-up? Is there bias? Did they check for citizenship?\n\nAt *best* such a statistic is an extrapolation based on a sample set. We don't make laws based on these. If those 60% of people want marijuana legalized, then they need to vote for the appropriate candidates during the appropriate election cycles. But even then it isn't so simple. Platform issues don't exist in a vacuum. A candidate who is in favor of legalizing marijuana may have other positions that are not popular. If the only candidate who wished to legalize marijuana also wanted to open the death penalty for crimes committed by minors, would you vote for him or her? It's a complex issue and candidates currently are not likely to make such promises. 60% is still very close to 50/50 and it's a polarizing issue. You're asking candidates to make a stance that could potentially rob them of half their votes. Not gonna happen yet.\n\nAnd even then it still has to be drafted as a bill, voted on in both houses, and signed into law. It's an arduous process.\n\nThat said, some places do allow for public referendums, where specific issues *can* be submitted for popular vote, but that is a process in and of itself.\n\nRegardless of how it gets there, it's a bit more complicated than: \"Our US Weekly online poll says 60% of subscribers were in favor of the legalization of Marijuana\" = *poof* Marijuana is magically legal everywhere, even the Moon.",
"/u/drafterman has the larger right of it, but it doesn't help that there's an entire industry based around incarcerating people for drugs offenses. Seriously. Have a look at the statistics behind the US prison system, and you will see that there's a vested interest in keeping marijuana criminalised in the US.",
"Ignore the guy that talks solely about the contributions and drafterman is missing two things. \n\nIt's mainly because that 60% of US citizens who are pro-legalization are not 60% of the voting population. The voting population in the US tends to lean further to the right than the actual general population. That's because the older demographics, who tend to be more conservative, vote in higher numbers. And in the end, the only thing that matters is who actually votes.\n\nThe second factor is that even if 60% of the voting population was pro-legalization, that doesn't necessarily translate into 60% of the legislature. Districts are currently drawn in a manner that concentrate progressive voters into a few districts, reducing the amount of progressive politicians in both the states and congress. \n\nThese two factors mean that pro-legalization politicians are not a majority even if pro-legalization is supported by a majority.",
"Prison, Oil, alcohol, and tobacco companies spend a lot of money on lobbying. They have a vested interest in keeping it illegal. It's always been an uphill battle for legalization. Even if only 30% of the people support keeping it illegal, they're being represented a lot more strongly in congress, by the corporate money. 60% of the people may support legalization, but they're not up on Capitol Hill hob-knobbing with the members of congress, so progress is slow.\n",
"Legalizing marijuana isn't an important issue for most people because most people do not use it. Between 5-10% of people regularly use marijuana. That means the other 90-95% of people probably aren't that concerned with whether or not it's legal even if they wouldn't mind if it is legal. \n\nFor most people, if you ask them \"Do you think marijuana should be legal?\" They may say \"Sure, whatever. Doesn't bother me.\" But it's not an important issue to them. They're not going to vote for a candidate because the candidate supports the legalization of marijuana. They're going to vote for candidates based on issues that are important to them.\n"
]
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| []
| [
[],
[],
[],
[],
[]
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|
||
akr5p7 | why do americans still want to work as coal miners? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/akr5p7/eli5_why_do_americans_still_want_to_work_as_coal/ | {
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"text": [
" > The average starting salary for a coal mine worker is $60,000. \n\nWhere else are you gonna pull 60k right out of High School in rural West Virgina?\n\nWhen the mines close, the towns and everyone in them have to move or face poverty.",
"So the problem here is that the communities that have grown around those few remaining coal mines are generally poor, and because everyone has grown up with \"This is your job, and it's a good job and you'll do it until you die\" as a philosophy there, it's REALLY hard to convince them that it's not a good job, or that they should try and learn something else, especially because learning a new career when you've been a coal miner most of your life is very difficult. ",
"We don't. There are only 50,000 coal miners left in the US. Walmart employs more than 28 times as many people as the entire coal mining industry. Also, technological advances have make coal mining more machine-oriented. It's much easier to tear down an entire mountain and sift through it than it is to dig shafts and send people down into them to collect the coal.\n\nThe emphasis on these workers in political campaigns is just a metaphor for changes in the economy affecting some areas more than others.",
"It’s not “want” so much as need. It’s an opportunity to make money. Health and safety go out the window when there’s a chance to pay your bills.",
"Where these mining towns are there is almost no other kind of job. You have to move away to find other employment, which takes money. \n\nAnd we still need coal. It still has value with energy production and so it still has to be mined and as such miners tend to make decent wages. "
]
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| [
[],
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[],
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||
1irf2l | do advertisers use annoying sounds in commercials -- like people crunching, for example -- on purpose? wouldn't this make people hate the product, like it does with me? | Do advertisers do this on purpose? Why? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1irf2l/eli5_do_advertisers_use_annoying_sounds_in/ | {
"a_id": [
"cb7c5zj"
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"score": [
3
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"text": [
"Advertisers are not trying to annoy you, but they are trying to get you to experience their product. If they are selling a crunchy cereal, for example, you can't taste it directly when you see it on the television or hear about it on the radio. But by playing a crunching sound effect, advertisers can show your brain that their product is crunchy. And hearing that crunch, like when you would eat it, for most people will create a whole bunch of related thoughts and feelings in their brains. Your brain recalls the other things that happen when you make that crunching noise while you are eating it. And seeing pictures of the food and hearing the crunch together can be enough to make people actually salivate, preparing their bodies to immediately consume that product.\n\nAnd this is what advertisers want. They want you to remember what eating something crunchy is like, and they want you to get hungry while seeing their product or hearing them talk about it.\n\nSome commercials get annoying because advertisers have also figured out that sounds and colors that are louder and more vivid than they are in real life can evoke stronger reactions from people. In general, our brains react more to stronger stimulation. But when a stimulus is too loud or too bright, it passes a certain threshold where we no longer associate it with eating. Then it just sounds out of place, fake, and annoying."
]
} | []
| []
| [
[]
]
|
|
94xjhi | why do people look so much less attractive without eyebrows? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/94xjhi/eli5_why_do_people_look_so_much_less_attractive/ | {
"a_id": [
"e3oiixn",
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"text": [
"It's because it's \"unnatural\". Biologically, at the core, we are attracted to people who look like they have good genes. We want to know that our offspring will survive.\n\nWe also know that people have eyebrows. Thus if someone doesn't have eyebrows, our brain says \"woah, that might not be a good mate because they dont have a thing that humans should have.\"",
"Also eyebrows are used to express emotion like surprise, anger, concern, confusion. It would make knowing how they feel more difficult. ",
"It's called the \"uncanny valley\". Something that looks very similar to a normal human face but not quite normal is very subconsciously disturbing to us. The same thing happens to us with robots and animated movies. \n \nIf you want an example, Google the movie \" Polar Express\". Viewers found it difficult to watch but couldn't express why. It was this effect."
]
} | []
| []
| [
[],
[],
[]
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|
||
32s2a9 | do bulls actually attack the colour red, if so, why? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/32s2a9/eli5_do_bulls_actually_attack_the_colour_red_if/ | {
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"text": [
"No they do not. Lets just say, if I trapped, and starved you for days, while whipping and attacking you, and I let you out of a cage and swing some cloth to taunt you. You most likely will attack me. That is the concept of it.",
"No, they don't. Bulls can't see red like we do because they are dichromatic. They're attracted to the motion.",
"As Sablemint mentioned: Bulls are colourblind and can't actually see the color red, it's the motion of the cloth that they react to, the cloth in bullfights is red because it's a colour that stands out which is good for audience, and doesn't get noticeably bloodied quickly. Additionally if you start waving a cloth around in front of a random bull they might not react too much, I'd still not recommend it though, but the bulls used in bullfights are meant to be wild and aggressive so they get \"poked\" a few times, maybe a little scratch of the whip here and there and maybe just a day or two without food. Also even if it wasn't too aggressive at first, that bloody spear that's stuck in his ass now probably changed his mind.",
"[Mythbusters actually tested this](_URL_0_) and what they found was that bulls don't go for the color red. They noticed, in fact, that bulls went for blue more than red (although it was not a large scale test).\n\nThey actually found that bulls went more for the movement of the flag than the color of it."
]
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| [
[],
[],
[],
[
"http://www.imdb.com/title/tt1081573/"
]
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|
||
2coae8 | why auto makers dropped the frameless doors? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2coae8/eli5why_auto_makers_dropped_the_frameless_doors/ | {
"a_id": [
"cjhet95",
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"score": [
2,
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3
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"text": [
"Explain frameless doors...",
"Like a hardtop, with no frame around the glass? IIRC, may have to do with rollover safety. If you don't have that frame you lose strength that would have to be added elsewhere. Plus, the windows don't always seal as well. ",
"Because they really didn't work too well. It was too hard to build a seal between the car frame and the glass, that worked well when closing the door, while allowing the window to slide up and down. Because you couldn't hold the glass in a channel, the window gets pulled away from the seal at high speed, unless you design it to push tightly against the seal, which makes the door hard to close and makes the window-winder mechanism stiff.\n\nThe door-window seal has to do different things to the door-car seal. Trying to make one seal do both meant that both things were done poorly."
]
} | []
| []
| [
[],
[],
[]
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|
||
3jpffn | what makes expensive movie cameras look so clear and focused opposed to conventional dslrs and camcorders | Cameras like the RED Epic sometimes look better than real-life while conventional DSLRs/Camcorders are usually blurry/hazy and less detailed. What's the difference? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3jpffn/eli5_what_makes_expensive_movie_cameras_look_so/ | {
"a_id": [
"cur8c9y"
],
"score": [
3
],
"text": [
"Well, I work with Alexa arris, reds, and dslr's \n\nHonestly they pretty much look the same, you can look at comparisons and unless they are generations apart or your looking at it extremely cropped, it's basically impossible to tell the difference. \n\nMany times when we film multimillion dollar films we will use go pros and dslr's in addition to the higher end cameras. You will never see the difference while watching the final product. \n\nThe only other difference would the lenses used, which Freddie on YouTube did a video on were they brought in professionals to try to tell the difference between a $100, $1000 and $25,000 lens and they couldn't. \n\nNext difference is what compression is used. The higher up cameras use raw uncompressed, but dslr's can use this too with mods. Then the higher up cameras a better contrast ratio. You can see more details in the shadows and highlights. \n\nReally though, you can not tell the difference if it's filmed properly. \n"
]
} | []
| []
| [
[]
]
|
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