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37y5fi | what is the difference between belarus and belarussia? | Currently watching the European Rowing Championships. Most commentators refer to tthe crews from the country as 'Belarus'. But there's one commentator who keeps saying 'Belarussia'. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/37y5fi/eli5_what_is_the_difference_between_belarus_and/ | {
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"The country is Belarus, the demonym for people from Belarus is belarusian.\n\nIn Russian the country is called Byelorussia. \n\nEither of those possible?"
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s69ed | why the trend toward "sleek" and "smooth", luxurious cars? | It seems like every car/SUV/minivan made nowadays is being redesigned to be sleeker, slimmer, more luxurious (and IMO, most of the SUVs look girly, or mom-y). Why this trend all of a sudden?
On a related note, when "old-looking" cars like [this one](_URL_0_) first came out, were they considered "attractive" or "cool" looking, or was that just ignored because all cars looked similar? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/s69ed/eli5_why_the_trend_toward_sleek_and_smooth/ | {
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"They are better on gas, and we have better construction techniques that use more fluid forming techniques out of single pieces of metal. In addition to what you said. ",
"There's design trends all through history. They tend to sway back and forth between styles or driving ideologies. \n\nAlso, efficiency has a lot to do with it. Aerodynamics are a huge part of fuel efficiency and cardboard box-shaped cars aren't good at aerodynamicking."
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3g5irr | how does the army national guard work? | Does the Army National Guard have boot camp? Do they pay your housing? What are incentives of the Army National Guard? Is it the same as the reserves? Do you need a diploma or just G.E.D.? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3g5irr/eli5_how_does_the_army_national_guard_work/ | {
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"I'm not sure about the requirements such as diploma / GED, but it works like this. I'm going to assume we are talking about an enlisted person, not an officer.\n\nWhen you decide to enlist in the military, you go to a recruiter and tell them that you want to enlist. You have 3 choices. Active duty, Reserves or National Guard. \n\nOnce you decide which component you want to go into, (AD, Reserves, or National Guard) you will sign up and get a date to go to Basic Training. Everyone who is enlisted goes to Basic Training. Once you graduate from Basic Training, you will go to your advanced (job specific) school. After graduating from that, you will go to your unit. If you are active duty, that unit will be at a military base where you will be stationed. Think, JBLM, Fort Bragg, Fort Benning etc... You will be provided housing and food there. If you joine the reserves or national guard, you will come back home and go to your unit for in processing. Once you have been assigned to your unit you will go to \"drill\" with them one weekend a month and 2 weeks a year. Usually the 2 weeks happen over the summer. \n\nAs far as incentives, it depends on what is in your enlistment contract. Some people get a cash bonus, some people get more money for college, some people get nothing. It all depends on your job. \n\nThe difference between the guard and reserves is that the Reserves is funded by the federal government and the Guard is funded by your state. The guard gets called up for local emergencies AND war but the Reserves is only deployed for war / training missions at the behest of the federal government. \n\nHope that helps. ",
" > Does the Army National Guard have boot camp?\n\nThe Army National Guard goes through the same training as active duty army and reserves for their basic training (where you learn the basics of being a soldier) and advanced training (where you learn how to perform your specific job in the army).\n\n > Do they pay your housing? \n\nWhile training, the ANG will pay for your housing, but when you're not training, you'll be on your own.\n\n > What are incentives of the Army National Guard? Is it the same as the reserves? \n\nThe incentives to join the Army NG and the Army reserves are different because the Army NG are a state-level organization, so each state will offer their own incentives to get people to join. The army reserves are a federal level organization and thus have their own incentives which are similar to the active duty incentives. You can search for the national guard in your state to see what incentives it offers.\n\n > Do you need a diploma or just G.E.D.?\n\nThe standards to join the active army, reserves, or national guard are all the same. A GED is sufficient.",
" > Does the Army National Guard have boot camp?\n\nYes. They go to the same basic training as people in the active army.\n\n > Do they pay your housing?\n\nIn general, no. There is such thing as full-time National Guard positions, and those people get the same pay and benefits as active duty soldiers.\n\n > What are incentives of the Army National Guard?\n\nBesides serving your country and state, their web site sums it up quite well: [_URL_0_]; extra pay, insurance and education benefits, credit toward a military retirement, and all other benefits offered to veterans\n\n > Is it the same as the reserves?\n\nIt's similar, but the focus is more on your state than your country. In general, you serve the same one weekend a month, two weeks a year. You *can* still be deployed to war if needed.\n\n > Do you need a diploma or just G.E.D.?\n\nThose requirements change based on what the army needs at the time and what Military Occupational Specialty (basically your job) you sign up for.",
" > Does the Army National Guard have boot camp?\n\nYes, Regular Army, Reserves, and National Guard all go to basic training together. A basic training platoon (depending on your job) might 1/2 Active, 1/4 Reserves, and 1/4 National Guard.\n\n > Do they pay your housing?\n\nWhen deployed, you're like any other active duty solder and get BAQ. For annual training or drill weekend, you'll be put up in the armory or barracks, or just be out in the field. You don't get any housing allowance while in reserve status.\n\n > What are incentives of the Army National Guard?\n\nRetirement (20 years in), GI Bill, VA loans, drill pay, tuition assistance, discounted life insurance, etc.\n\n > Is it the same as the reserves?\n\nIn terms of benefits, yes. Generally, in the National Guard you get the federal benefits that a Reservisit might get, plus any state benefits available. This might mean getting the Montgomery GI Bill (federal) and state tuition assistance. This was the biggest reason I joined the ARNG instead of the Reserves after active duty.\n\nThe biggest difference is that (generally) a National Guard unit is a state-based division, with all parts being made up by ARNG soldiers. This means many ARNG units are more likely be made up of combat MOSs vs. Reserves which are more of a support role for active duty. You're also more likely to deploy as a unit than a Reservist. As a disclaimer, I generalizing with these statements and everything I said can probably be picked apart.\n\nWhen you enlist, you also give an additional oath to defend your state and state constutition. In my case, this meant going door-to-door checking up on the elderly during major snow storms.\n\n > Do you need a diploma or just G.E.D.?\n\nDepends entirely on your state and how badly the manpower shortage is.\n\nSource: I served in the ARNG after I was on active duty. Was also stop-lossed in the ARNG before I ETS'd and was a recruiting assistant on ADSW while in college."
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3oallv | why does a scalp feel bruised/sensitive after being in a ponytail for a long time? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3oallv/eli5_why_does_a_scalp_feel_bruisedsensitive_after/ | {
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"Hairdos that pull tightly on hair, particularly in a lateral direction along the scalp, actually hurt hair follicles. If you do it too tight for too long, the ones being tugged on the most will actually die, which leads to a receding hairline. "
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cd1d8l | - where does the carbon that trees store, go? | I have seen a lot of posts where trees can save us.
Things really don't dissappear AFAIK, so if the trees eats the carbon dioxide, where does it end up?
I did not spend my attention in school to learn, sadly enough. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cd1d8l/eli5_where_does_the_carbon_that_trees_store_go/ | {
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"It becomes part of the wood (the tree's own body). Trees are made largely of carbon.",
"Trees, like all organic matter, contain a lot of carbon, in the simplest terms, the carbon absorbed by trees gets used by the tree to grow bigger.\n\nIn a bit more detail: trees harness energy from sunlight which is then used to break down carbon dioxide into carbon and oxygen. The carbon is then used to create glucose (essentially a type of sugar) which then becomes the organic matter that we recognise as trees :)",
"It ends up as part of the tree. Trees consume carbon dioxide and emit oxygen as part of the process of photosynthesis. The carbon then gets used to make glucose and a bunch of other things. All living things are made up of a lot of carbon.",
"The inorganic carbon in CO2 that trees absorb from the atmosphere is turned into organic carbon (i.e like sugars for example) through a series of chemical reactions. The process is called photosynthesis.\nSugars and other organic substances made from carbon are used by plants as a source of food or for constructing their own body (i.e growth).\n\nHope this helps you."
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27gbrg | why do (more) women not take birth control pills continually to never have periods? | As a man, it sort of blew my mind reading in the thread on the front page that 1/4 of the "birth control" pills that come in a packet are placebos. Birth control pills prevent menstruation while they are being taken. It is only because women don't take these pills for 1 week out of a month that menstruation occurs.
Apparently, there are no major medical consequences to simply taking a continual dose of birth control pills. The only thing I could find from a cursory search is that minor ["unscheduled" bleeding can occur in the first months after adopting this method](_URL_0_). And, as a result, women who do will never have a period.
So, if having a period is generally unpleasant and if stopping it is possible and safe, why don't more women do it? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/27gbrg/eli5_why_do_more_women_not_take_birth_control/ | {
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"It's actually a subject of debate whether taking oral contraceptive continuously has no medical consequences. The fact is that this is a fairly new idea, and there's no enough data to say what the long term effects would be.\n\n[This website](_URL_0_) gives a good rundown of the pros and cons. It seems like a majority of doctors think it might be a good idea for some women, but more research is needed before we can be sure.\n\nDisclaimer: I am neither a doctor nor a woman. However, I do talk to doctors and women from time to time.",
"Analogy is you need to do an oil change on your car every now and then....",
"As a female, even though periods are indeed unpleasant, they are also kind of a hormonal release and an indication everything is all good in the hood, know'm sayin? Men don't really understand the hormonal tempest that can swirl inside the female body. A period is the calm after that storm (PMS). Also the only time I have not had a period after puberty was for several months when I was extremely ill. My body was just not functioning properly. Also if I got pregnant, my period is a good way to tell early on something is seriously up. So for those reasons, I would not tamper with my body's natural process in that way. "
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8tdv9p | how do people who live in eastern asian countrys eat so much yet stay so healthy? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8tdv9p/eli5_how_do_people_who_live_in_eastern_asian/ | {
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"By healthy I assume you mean lean with a low body fat percentage. It all comes down to the units of energy consumed versus the units of energy burned; some people burn more calories with more physical activity while others can consume a lot more without getting \"fat\" because they carry a lot of muscle mass.\n\nGenetics might play a factor in this along with your specific diet. Anyone can get lean and strong with enough effort and discipline. ",
"This should be tagged as biology, not culture. Weight gain/loss is determined by how many calories you take in, compared to those you expend based on your baseline metabolism and activity level. Ingredients can have more or fewer calories, but healthy food and unhealthy food with the same amount of calories will cause the same weight gain - you will simply feel differently after consuming it.\n\nA few things to think about on your end are snacks between meals or drinks during meals - this is frequently where people consume calories in significant amounts. Try taking a day where you count every single thing.\n\nOn their end, keep in mind that if you see videos of these events, they are likely not the norm. People don't take videos of their everyday meals, they take videos of interesting food they eat, or of interesting events in their lives.",
"Less added sugar, less carbs. When you eat a diet where you get your energy based off of carbs you are running on glucose, basically your body is always in an insulin rush. This makes you fat. If you get most of your energy from good fats insetad of sugars youre body will shed it's fat.\n\nSo more meat based fats or pure plant based fats (olive oil, coconut oil etc, not vegetable oil), butter and fat are better for you than the things they've tried to tell us are healthy (vegetable shortening, vegetable oil, margarine).\n\nPeople in East Asian cultures tend to eat more protien and vegetables. Even rice isnt normally enough net carbs (carbs minus fiber) to push them over.\n\nIn the western world everything is carb based, if it's not we add wheat or corn into it for no reason. We also have added sugars in processed foods. If you don't want to be fat only buy food from the outer perimeter of your grocery store (meat and produce) and skip the aisles of processed foods.",
"I’m not a nutritionist but asian cuisine (there’s different types) is lots of rice and noodles, vegetables, fish and fish based products\n\nThe regular “western” diet is lots of butter, bread, milk, pasta/noodles, and added sugar \n\nThere’s a debate between fat/carbs but different diets probably play a roll\n\nAnother thing is fast food, some countries that have been getting Newley introduced to fast food have been getting fatter "
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5h1ben | why aren't password special characters universally agreed on? | I'm not asking about the length or use of caps. I'm wonder about why isn't there a universally agreed upon standard of special characters (the !@#$ most make you use) that can be used by all password programs? Some allow a ! but not a ?, but another does the opposite. I just want to come up with one sweet and difficult password to use across all platforms. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5h1ben/eli5_why_arent_password_special_characters/ | {
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"Because there is no standards group maintaining this. And because some special characters have special meaning in certain locations. It wouldn't matter if the person writing the password code knew what they were doing and used modern best practices, but there's still some older code that uses older patters where having a ? in the message means something like \"move on to the next field\".\n\nAlso, please don't use one sweet and difficult password across all platforms. The biggest danger these days isn't a hacker guessing your password- any halfway decent service will lock them out after a few attempts. The biggest risk is someone stealing a password database from one website (maybe one which doesn't protect the passwords as well as they should), them having all the time in the world to crack the passwords, and then trying the same username/password combination on other popular sites. For this problem, it would actually be better to have a weaker but unique password on each website.",
"Other than the answer /u/popisms gave, the major reason is just piss-poor development. From a software development standpoint there is no reason whatsoever to blacklist characters in a password. \n",
"Software developer here,\n\nI have some domain knowledge on this subject and I also have acquaintances in some internet and information security companies, who specialize in things of this nature.\n\n > I just want to come up with one sweet and difficult password to use across all platforms.\n\nDon't do that. Per se.\n\nWhat you want to use is a password manager program aka a \"key ring\" program. This program can typically be installed on a USB stick for Windows, Linux, and Apple (you should have all 3). On the stick will be the key ring itself, a file that is an encrypted password database. It can also store the username and the login url and other notes for you.\n\nWhat you'll do is have one, sweet, master password that you will memorize, which unlocks your key ring. The program maintains passwords for all your needs, and will put the password you need into your clipboard, (typically) encrypted so all you have to do is paste it into the password field of whatever. You never have to see it or know it.\n\nThese programs do way more than just store passwords. When you enter a new client and password, you specify all the constraints on that password - length, special characters allowed or banned, required complexity, etc - and it will generate a secure password for you, one that is heuristically difficult and too complex for you to memorize. You never have to need to actually know or see it. If you need a new password, the program can generate a new one for you and store it in your key ring.\n\nJust as you don't leave your keys in your car, you don't leave your keys in your USB port. If you need a password, plug it in, retrieve the password, and unplug the stick. Don't use this stick for anything else, this is it's purpose. You can get tiny thumb drives practically for free and attach them to your keychain. Keep a backup drive in your dresser or even better, a lock box at your bank - they still offer those services and are basically the only reason to have any sort of business with a traditional local brick and mortar bank.\n\n > What if I'm using a computer that won't let me plug in a USB stick or run a program off it.\n\nYou're talking about using a public access computer. You need to seriously consider why the hell you would want to use a public computer that isn't yours, you can't trust, and should assume the very real possibility it's been compromised. I absolutely would never trust a library or university computer, as they're huge targets for this very reason. Expect no privacy and no right to privacy on such a machine. Move on. Your FB post can wait, if you had no other means.\n\n > I'm not asking about the length or use of caps. I'm wonder about why isn't there a universally agreed upon standard of special characters (the !@#$ most make you use) that can be used by all password programs? Some allow a ! but not a ?, but another does the opposite.\n\nSecurity is hard and service providers are *astonishingly* terrible at it. The people in charge of these sorts of decisions are often using extremely dated knowledge and/or technologies, or are ignorant, arrogant, and lazy. There is *ZERO* excuse why every password doesn't support unicode character password of arbitrary length without it reducing down to old technology, bad knowledge, or slack.\n\n---\n\nYou're not defending against people, but programs. The most important thing is your password is long. Second is that it uses a wide character set.\n\nAutomated attacks that try to brute force passwords for a given known user account will try to guess common passwords. So a complex or long password can defeat that.\n\nBut hackers are going to break into a system using an exploit, not a password, and steal the password file. It doesn't contain your password, but a \"hash\", which is generated from it and can't be reversed to reveal the password. They're going to use multi-terabyte \"rainbow\" tables, which is a database of hashes to passwords to look up your hash and instantly know the password. These tables are generated before hand, and for every additional BIT in your password, the table has to double in size. And generating these tables can takes months, and are per target - so what works for Target won't work for Amazon because of how each service is going to \"salt\" their hashes to make them more unique. So if they generated a table for every US English keyboard UTF-8 printable character password up to 64 bytes long (what you would typically type in on a keyboard), and your password is 65 bytes, you're almost certainly safe (mathematical flukes called hash collisions mean a different password can produce the same hash, it's just as valid as your password for your account, with modern crypto, the're essentially - ELI5 explaination - impossibly rare)."
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3xlvb5 | if the constitution protects against double jeopardy, how can trials go an appellate court? | If someone has already been convicted, how can they be tried for the same crime twice? Isn't this against the 5^th amendment? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3xlvb5/eli5_if_the_constitution_protects_against_double/ | {
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"In what way would it violate the rule? Keep in mind that the *defendant* is the one who asks for the appeal; without the appeal, he is guilty, and the appeal can't actually convict him (it's not a second trial). ",
"The process that happens in an appellate court or other higher court is not considered a separate trial, but rather a continuation of the original trial. What the appellate court tries to determine is whether the first court did a good job deciding the case, not (directly) if the defendant is guilty or not. The American Bar Association has a good explanation [here] (_URL_0_)."
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90z982 | why is it so hard to get that old 'hand drawn' look in modern anime/cartoons using computer animation? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/90z982/eli5_why_is_it_so_hard_to_get_that_old_hand_drawn/ | {
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"It's not done very often because animating something that high quality would take a really long time. It's possible, just insanely time consuming.",
"There's a lot of reasons why old hand drawn animation looks different than today's computer animation. \n\nComputer animation can still be hand drawn with a tablet or Cintiq, but often times it'll be a mix of hand drawn poses and reused poses or parts (for example you may have a library of 100 different hand poses or mouth shapes to reuse). This saves a lot of time and keeps the drawings consistently \"on model\", but definitely has a different look to it. The more you reuse a library of poses/parts, the more likely the animator will plan their scenes with those poses/parts in mind and the more it looks \"Flashy\" (or maybe these days \"Toon Boomy\"). There were ways of achieving the same effect in older animation by tracing over parts of previous poses or reusing entire scenes, but even with tracing there are going to be some differences. This is probably most noticeable in computer animation that only uses a handful of mouth poses; even if it's just subconsciously, you can tell that the same 12 or 15 mouth shapes are being used for dialog, and maybe some additional shapes for extreme expressions. Even worse is if you're limited to a set of pre-approved poses; the animation starts looking very \"samey.\"\n\nAnother difference is that old animation was drawn on paper, then clear celluloid was laid over top to add the ink lines, and then flipped over and the back was hand painted. This leads to a number of artifacts that are difficult to reproduce in digital animation or simply undesired. First, you have slight inconsistency with lines from frame to frame, called \"line boil\". For a big expensive production (like Disney or Richard Williams) the animators are *very* careful to keep those lines as consistent as possible; Richard Williams in particular was a perfectionist and would require his animators to redo a scene if the lines were off by as little has half the width of a pencil stroke. This can still happen on a digital production but it's easier to avoid and easier to fix, so even low budget TV shows usually won't have line boil unless it's intentional.\n\nOther artifacts included mis-colored cels that would sneak in, especially in TV animation where you had tight deadlines and low budgets; it's just too expensive to ink a new cel, repaint it, and re-shoot it. Fun fact: because film was so expensive, the camera operator was often the highest paid person on the production; you had to get it right the first time or you can destroy your budget. In addition to mis-colored cels, there was also inconsistent thickness to the paint which leads to subtle changes in the color. \n\nThere are no color inconsistencies in computer animation because you're usually going to be working with a preset color pallet and pre-colored body parts/props. Even for productions that need to be colored frame by frame, if you spot an error it's really cheap and easy to fix it with digital ink and paint software. And since it's not shot on film anymore, there's no film grain or issues with focus being slightly off. Digital colors can also be much more saturated and sharper contrast than what you get with film. \n\nThe cels also aren't 100% transparent, they block out a small percentage of light. This meant that scenes with more cels stacked on top would darken the background elements. As the scenes play out, you can see this darkening/lightening of the background elements as layers of cels are added and removed. With digital animation, you can have hundreds or thousands of layers without the darkening/lightening effect. \n\nAnd finally, animation style has changed quite a bit over time. Compare the \"rubber hose\" style popular in the 20's and 30's to the limited style that UPA popularized in the 50's, to the zip and pose style in the 2000's. There's also house styles; there's a clear difference between Warner Bros and Disney style, or Pixar and Dreamworks. It's not just the animation style, either, it's also things like character design and color choices. You can certainly emulate older animation styles on the computer, but audience tastes change over time and animation directors want to stand out from the crowd so you don't see the older styles as often in modern productions. Computer animation also lets you do interesting things that would be prohibitively expensive for hand drawn animation. Consider the characters in Foster's Home for Imaginary Friends; many of those designs would be an absolute nightmare for hand drawn animation, especially on a TV budget. But thanks to Flash and a huge library of reusable body parts, poses, and animation sequences, the costs are kept lower and you get a really unique cast of characters and an interesting animation style."
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zhjnj | how american college applications work. | Basically I have to start applying for colleges and I have no idea what the fuck I'm doing. On the Chapman website, it says they have a school especially for film, Dodge, which has its own application specifications. If I want to minor in film but major in something else, do I have to apply to both Chapman and Dodge? Are they the same school? If I go in undecided but decide I want to take some film classes, do I have to apply then, or can I just take the classes? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/zhjnj/eli5_how_american_college_applications_work/ | {
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"So, for a bit of clarification, mostly for the stuff below, a university is made up of colleges. a college of liberal arts a college of business, et cetera. \n\nyou only have to apply directly to college if you want to major in it. you can usually minor in a field without being certified by the college, while you do need to be certified in order to major. you can also declare a major, usually at any time within your first two years, but you have to reach higher standards than if you started out in the college if that major happens to be competitive.\n\nthe rules are different for every school so I would talk to an advisor at that particular school if you want better information.",
"You would apply just to the one where you anticipate majoring. This won't even be an issue with all schools, though. Universities are typically divided up this way, but colleges are not. "
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fpjh33 | i have a cpap machine for sleep apnea. how similar / different is it from a medical ventilator? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fpjh33/eli5_i_have_a_cpap_machine_for_sleep_apnea_how/ | {
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"The CPAP machine is simply designed to keep a small positive airway pressure (hence the name) in order to keep the airway open. You still must breathe, it doesn't do it for you. A ventilator actually will breathe for the person, so it will put positive then negative pressure , usually through a breathing tube that's down the trachea into the lungs, not through a mask at all. It will also filter the air coming out and going in, to ensure a good, clean, sterile breathe with no contamination of the surrounding environment."
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4regmv | what makes popular music recordings you hear on the radio sound so "good"? | Compared to home recording or local recording studios, what makes recordings bands like Maroon 5 sound "better" than other bands? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4regmv/eli5what_makes_popular_music_recordings_you_hear/ | {
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"Professional mixing and mastering engineers.\n\nBasically, for bands as large as Maroon 5, you have multiple professionals mixing the song to get it to sound as clean, clear and crisp as possible. The better the mix engineer, the better the song will sound. \n\nBut it also all comes down to the ear of the mixing engineer. you can know the ins and outs of song mixing/editing but having a good ear for audio quality is probably most important imo.\nSo naturally, having multiple people working on it, or at least having another engineer checking over the first engineers work is like having someone edit your writing.\neven the best writers in the world can benefit from an outside revision/opinion.\nbut again, the bigger the band, the better the mixing engineer hires will be\n\nMastering is **basically** eqing/cleaning up the final audio file of a song and making it louder through compression \n\nThe human ear thinks louder= sounds better\n\n"
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a3bnsd | how come no one has prosecuted the president yet? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a3bnsd/eli5_how_come_no_one_has_prosecuted_the_president/ | {
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"If your gonna take a shot at the king, you better not miss. Any prosecutor worth their salt is gonna make sure all of their ducks are in a row before bringing anything forward, and with something as big as impeachment there are a lot of ducks. For reference watergate took roughly 2 1/2 years from start to finish and that never even reached the impeachment stage. This investigation is going light speed in comparison. "
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6s3g83 | why isn't drug testing mandatory for politicians? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6s3g83/eli5_why_isnt_drug_testing_mandatory_for/ | {
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"Politicians are the ones that would put these new laws in place. Also, some govern places where certain drugs are now legal. They also don't operate heavy machinery or have a direct impact on public safety. "
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1k428c | if it takes so many processors to simulate one second of human neural activity, why are processors so much more accurate and faster than brains? | I read an article recently (if anyone could provide a link, that would be appreciated) that said that it took lots of processors (I forget the number, but it was a lot) and about 40 minutes to recreate one second of the brain working. What I don't understand is how I can perform long calculations, perform thousands of instructions to keep a game running, and run an entire operating system on my computer, when it takes me seconds to do two digit addition or memorize a phone number. Processors seem so fast and accurate, so why does it take so many to simulate the much slower and sloppier human thought? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1k428c/if_it_takes_so_many_processors_to_simulate_one/ | {
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"Short answer: because human brains are doing things WAY more complex that are also much more important, evolutionarily speaking. Math equations beyond \"two lions means twice the lions that want to eat me\" are not as important as regulating bodily functions, cataloging dangers, remembering safe behaviors, socializing and procreating, etc. I'll post a whole thing about sight to show you just how complex it can get.",
"Processors are very good, extremely accurate and very fast - but only at certain types of problem.\n\nA processor can very easily solve any problem that can be expressed using an algorithm - a series of steps that can be followed, one at a time, to tell it how to solve the problem.\n\nThe difficulty is that our brains don't work this way. There is no algorithm that we know of which can accurately simulate what the brain does or how it does it. Our brains, although nowhere near as good as computer processors at solving logical or mathematical problems that can be written as an algorithm, have very complex internal workings that are very good at solving problems that *can't* be written as algorithms.\n\n**ELI5 analogy:** think of brains and processors as types of car. They look very different, but appear - at first glance - to do similar jobs.\n\nThink of the brain as an off-roader. And the computer processor as a racing car.\n\nThe racing car (processor) can get around a race track (solve mathematical problems) extremely quickly. The off-roader (brain) can get around the race track (solve the same problems) too - but it will take a bit longer.\n\nOnce you're off-road, though (thinking about more complex problems) the off-roader (brain) is king. The racing car (processor) probably can't get around the course (solve the problem) at all - and if it can, it will have to be done very slowly and very carefully.",
"A neuron detects whether or not a certain threshold has been passed, and if so, it 'fires', passing the signal on to perform some action.\n\nThis can be modeled as an equation with a number of terms equal to the number of 'inputs' - in the case of a brain, the number of synapses. It is basically summing them together and answering whether or not it should set itself off. This is between one and a hundred thousand for a human brain, though some animals have so few that we can actually create circuits to interface with them (such as snails).\n\nAssuming an average firing rate per neuron of 10/second, 10,000 synapses per neuron, and a hundred billion neurons, this gives a naive approximation of ten thousand million million additions per second, and is probably on the low side even for this naive model.\n\nThis does not model learning or memory of any sort, or mental state (happy/sad, etc). \n\nDifferent neurons in your brain have different numbers of different receptors for different neurotransmitters. The relative densities of these chemicals are not constant, nor are the receptors. This adds some orders of magnitude more complexity to each neuron, multiplying the above still further.\n\nOf special note is that this is *all bandwidth*. A single neuron firing is not just a computation - but a transmission, to potentially a hundred thousand neighbors, representing, in our incapable-of-learning-or-memory toy scenario, of a megabyte per second of data, per neuron.\n\nThat's all any individual neuron can do, however. Alone, its power is quite limited, and there are certain computational functions that require multiple layers of neurons - not just individuals - to work.\n\nSo when you see\n\n43+19\n\nFirst, the neurons in your eye detect the edges of those symbols, and transmit said symbols to your brain, where pattern recognition decodes these signals into their base concepts. These then get grouped into larger tokens, '4 and 3 next to each other is 43'. Then the + signal triggers some level of conscious thought that this is actually a problem.\n\nFor addition, there's actually a circuit in our brain that is somewhat 'optimized' for this, where it recognizes the sequence and can process a meaningful answer very quickly (there is some weird Japanese mental abacus game that abuses this, I forget the term - but the speed is ridiculous).\n\nFor multiplication, this isn't true, however, and we have to rely on our memory and learned techniques. This is, in comparison, ridiculously slow - you're manually applying patterns, you've got no built in hardware to do this.\n\nProcessors come with this hardware purpose-built for just this exact task. Even the subunit in our brain is a kludge in comparison - processors are getting close to being optimized down to the atom for this.\n",
" > Processors seem so fast and accurate, so why does it take so many to simulate the much slower and sloppier human thought?\n\nThe lots of processors you mentioned aren't simulating \"human thought\" - they are simulating [neurons](_URL_0_) (the cells that form the brain). Neurons does a whole sort of things, and we don't quite understand it all yet - but we know that the activity of neurons doesn't originate *just* human thought, but regulate processes through the whole body, most of it being unconscious (that is, you don't even know about it).\n\nThe reason it takes so much processing power to simulate a brain is because it's *huge*! In the human brain, there is about 100000000000 neurons (1 followed by 11 zeroes) and each one is connected to about 10000 other neurons, and they all work in parallel, that is, at the same time. If you had a computer with that many processing entities (such as: 100000000000 processors), each one connected to tens of thousands other entities, you could have a shot in simulating the brain in real time. But you don't!\n\nWe are stuck with processors that can't handle well such massively parallel task. For example, modern graphic cards have about 1000 very simple processors, and the connections between them are very limited. What we usually call \"processors\" - the CPU - are usually restricted to 8 more complex \"cores\", which are processors inside the CPU.\n\nWe try to cope with this using the fact that modern processors operate much more faster than a brain. Each neuron can fire typically once in some milliseconds, while the fastest processors make a operation once in some nanoseconds. There is one million nanoseconds in one millisecond, so if a neuron could be simplified to a single operation you could hope to simulate one million neurons in real time, with a single processor, going from one to another in succession (do a operation for the first, one for the second, etc). But each neuron is connected to many others - and you need to consider each such connection - and modern processors suck at dealing with very large amounts of data. Also, neurons are more complex than a single operation anyway. (PS: the reason the brain is so \"slow\" is because firing faster consumes more energy, and the brain is already the biggest consumer of energy in the body)\n\nBut there is the even greater problem of memory bandwidth (how to transfer very large amounts of data between parts of the computer), because memory is likely to be the bottleneck for such massive tasks. Data transfer in modern computers have a centralized, top-down structure, where each subsystem is connected to other using \"buses\", like traffic flow (smaller roads connected by avenues). When processing too much data, the bus might become congested, making each system wait for data transfer. This is different from the decentralized, massively interconnected network of neurons, which is much more like a p2p network.\n\nI also point that any such simulation won't tell us what the brain would actually do, because we have to simplify the theoretical model of a neuron to make the simulation feasible. So the simulation is slow *and* inaccurate.\n\nI wrote some bits on a reply to the currently most upvoted answer [here](_URL_1_) but it reads a bit more technical."
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7279r1 | if alcohol has been proven to cause cancer and other diseases, why aren't bottles covered in warning labels like cigarettes? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7279r1/eli5_if_alcohol_has_been_proven_to_cause_cancer/ | {
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"Ahoy, matey! Yer not alone in askin', and kind strangers have explained:\n\n1. [ELI5: Why are there health warning labels on cigarettes and not McDonalds, soft-drinks, processed meat, or on the side of Supercars and Bikes? ](_URL_1_)\n1. [Why is Alcohol not illegal because of how much harm it brings people and society? Why is it not treated like other drugs? ](_URL_0_)\n1. [ELI5: Why are tobacco products required to have health warnings on them when other unhealthy products such as Alcoholic drinks and Soda drinks don't? ](_URL_2_)\n",
"There are warning labels on alcohol, they cover the subjects of Fetal Alcohol Syndrome and Drunk Driving. Generally speaking, you have to be a a heavy drinker to substantially increase your risk of cancer/cirrhosis due to alcohol which doesn't apply to most drinkers. Hence, the reason a warning label isn't as warranted as it would be for smoking. "
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"https://www.reddit.com/r/NoStupidQuestions/comments/6bc9g8/why_is_alcohol_not_illegal_because_of_how_much/",
"https://www.reddit.com/r/explainlikeimfive/comments/3q7epx/eli5_why_are_there_health_warning_labels_on/",
"https://www.reddit.com/r/explainlikeimfive/comments/2w8xf9/eli5_why_are_tobacco_products_required_to_have/"
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lhcbs | how the nes zapper gun (like the one used in duck hunt) knew where you were pointing on the screen. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/lhcbs/eli5_how_the_nes_zapper_gun_like_the_one_used_in/ | {
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"The Zapper doesn't actually \"shoot\" out light. Instead, it's the reverse: it's a light sensor. When you pull the trigger, the screen turns black and the targets (ducks, discs, enemies, etc.) would flash a white square. If the Zapper is pointed at a white square, it registers as a hit. This is also why it's possible to cheat by pointing at a bright light source (light bulb, window, high-brightness TV, etc.)",
"[Really great video about how the Zapper works, also answers your question.](_URL_0_)",
"The Zapper doesn't actually \"shoot\" out light. Instead, it's the reverse: it's a light sensor. When you pull the trigger, the screen turns black and the targets (ducks, discs, enemies, etc.) would flash a white square. If the Zapper is pointed at a white square, it registers as a hit. This is also why it's possible to cheat by pointing at a bright light source (light bulb, window, high-brightness TV, etc.)",
"[Really great video about how the Zapper works, also answers your question.](_URL_0_)"
]
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12k486 | why does usa elect their president based on who gets the most electoral votes and not by popular vote? | It is to my knowledge that in 2000, 48.4% of every American who voted wanted Al Gore as president, yet George W. Bush who had 47.9% won. Why is that? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/12k486/eli5_why_does_usa_elect_their_president_based_on/ | {
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"Cause the people who wrote the constitution realized that Americans could not be trusted to vote.\n\nTherefore the electoral colleges were instituted to correct 'mistakes' the voters made",
"These vids explain far better than I could:\n\n* _URL_1_\n* _URL_0_\n\nEnjoy.\n\n",
"Probably the best reason for the Electoral College I've seen in modern times is Sandy.\n\nThe US is very regionally fractionalized. This means that the NE will likely all go blue and the south all red. If we went on straight popular vote then a natural disaster suppressing turnout in one part of the country but not effecting another could change the outcome of the election.\n\nWith the Electoral College the damage of widespread low voter turnout in a single region but not another is negated since that region's EC votes are based on it's total population not the percentage of the population that voted.",
"It's a system designed to balance the different states. Without the electoral college, only the heavily populated states would matter. With the electoral college, several states in flyover country matter. It's designed to help balance out the large and small states. It's not perfect, but what is?",
"At the start of the country, many of the people who wrote the constitution saw the US as a strong alliance of many \"states\" rather than a single nation. The President was meant to be a representative of the many states that made up the alliance, not a representative of the people directly. ",
"The US was founded by many rich and educated men. In a time where education was considered a luxury that only the rich had, most people were uneducated, especially the lower classes. The founders of the US knew this, and were afraid of the common people electing an incompetent man as president. The electoral college was designed to correct the people of they made mistakes.\n\nThere's also stuff in the Federalist papers about how the Framers believed that republicanism was better than democracy and that democracy was the degenerate and corrupt form of republicanism, but that requires more in depth explanation than a five year old would understand.\n"
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2bt3p4 | why is it that some people absorb information easily while others can't? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2bt3p4/eli5_why_is_it_that_some_people_absorb/ | {
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"It is training. Also - we absorb different kinds of information differently. For example I usually have no problem picking up new math/logic concepts, but I can't keep up with history, and can only understand music from a math/order standpoint.",
"If you pay attention to something you find interesting, you'll remember it. If you aren't paying attention, or don't find the material interesting, you won't remember it. By absorbing, I assume you mean remembering something long-term. It's not scientific, just based on my experience."
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46xidt | georgia's "religious freedom" bill | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/46xidt/eli5_georgias_religious_freedom_bill/ | {
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"When it passed through the House the main 3 points were as follows\n\n-- It cleared ministers from having to perform marriages that violated their religious beliefs; (meaning a minister that refuses to perform a LBGT marriage cannot be sued for discrimination)\n\n-- Business owners could remain closed on Saturday or Sunday if working conflicted with their religious beliefs; and\n\n-- Religious institutions did not have to rent facilities for ceremonies that violated their beliefs.\n\nThe Senate added \"prohibit discriminatory action against a person who believes, speaks, or acts in accordance with a sincerely held religious belief or moral conviction that marriage is or should be recognized as the union of one man and one woman or that sexual relations are properly reserved to such marriage.\" (meaning for example someone whose religion states that LGBT is wrong cannot be discriminated against for saying this or refusing service to LGBT people.)\n\nSince the Senate modified the bill it has to go back to the House for their vote again. "
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c9vsg6 | why is it preferable for an airplane to have the propeller pulling at the front, instead of pushing from the back? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/c9vsg6/eli5why_is_it_preferable_for_an_airplane_to_have/ | {
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"They airflow from the propeller at the front creates more lift as it transfer across the fuselage. It also helps the vertical stabilizer.",
"Generally propeller placement actually comes down to engine placement.\n\nYou need the center of mass of a plane to be in front of the center of lift otherwise the nose of the plane will constantly be lifting up and trying to stall you out. This generally calls for the big heavy engines to be in front of the wing.\n\nThere are a bunch of designs that have made it work, from little ones like the [Saab J21 fighter](_URL_1_) to bigger ones like the [Convair B-36 Peacemaker strategic bomber with 6 engines](_URL_0_), but it adds a fair bit of complexity to the design, and complexity generally equals weight, and weight is something you're trying really hard to avoid\n\nOther downsides for it are that the prop wash actually helps generate more lift on a propeller plane as you're shoving fast air across the wings, and having the prop blow air across the engine helps keep it cool and reduces the risk of engine fires. If your prop is behind then wing then the wing goes through the air before the prop can causes turbulence which reduces the propeller efficiency by a few percent as well which requires a stronger(aka heavier) engine than if it were in front.",
"The dirty air from the propellor wash over the wings does not increase lift (actually its likely to decrease lift), and cooling is not an issue in modern aircraft engines. The main reasons are stability and access to undisturbed air at the front of the aircraft.\n\nFor stability, think of pulling vs pushing a shopping cart while running. Both are fine in a straight line, but as soon as you hit a rough surface or turn, pushing will be much harder to control, as you have to work to correct the random imbalances. Pulling, either the shopping cart or the aircraft, is much more self correcting. Its called a stable vs. unstable equilibrium. In an unstable equilibrium like pushing from behind a cart or a rear mounted propellor, small unwanted influences like bumps in the ground or pockets of differences in air density will be much harder to compensate for. \nSome planes, especially fighter jets, are designed to be in unstable equilibrium for increased maneuvering performance, but mistakes are much more unforgiving and a computer running a controls algorithm is often absolutely needed to maintain control. Civilian or less performance oriented transport aircraft don‘t need that level of maneuverability and thus stability is prioritized. \n\nAlso, at the front of the aircraft, the propellor has direct access to the freestream, undisturbed air, meaning its performance is more constant and predictable. Put it behind a wing, and go into a steep dive or climb, and suddenly only half the propellor is experiencing remotely freestream air.\n\nEdit: there‘s a reason why the examples in the other comment are pictures in black and white. Before we had computers, not as much of this was known or could be tested, so aircraft design was pretty monumentally terrible compared to anything designed with the help of a computer."
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3qm48s | nitrogen fixation | I've read a lot about it but my teacher did a crappy job of talking about it in class, anyone have any help? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3qm48s/eli5_nitrogen_fixation/ | {
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"Basically, nitrogen is really, **really** important for living organisms. Unfortunately, most of the nitrogen on Earth is in the atmosphere in the form of N2 and most creatures lack the tools to break it apart and make use of it. \n\nFortunately, there are bacteria that *do* have the tools to do so. They are able to convert nitrogen forms like ammonium (NH4) which can be used by other creatures.",
"Nitrogen is used in many many biological processes. However, even though there is more nitrogen in the air than oxygen, the nitrogen in the air is useless due to the triple bond holding the N2 molecules together being very very strong. Many organisms cannot use this nitrogen, but fortunately there are some plants and bacteria which can convert that nitrogen in the air into a more useful form of nitrogen, and fix it into the ground, so that other plants can get that nitrogen, then animals that eat the plants get that nitrogen, and so on."
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3chhdg | why do some plants have red leaves instead of green? do they get less energy from sunlight? | Here are some examples.
_URL_0_ | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3chhdg/eli5_why_do_some_plants_have_red_leaves_instead/ | {
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"The colour green comes from a molecule called chlorophyll in plant cells. I believe chlorophyll can come in different types, that capture different wavelengths of sunlight. In most plants, all wavelengths except for green are absorbed, so green is reflected back. That's why they appear as green. \n\nDuring the fall, the chlorophyll can degrade and/or change, and as such, the red-orange-yellow wavelengths of light are reflected back at us, giving the leaves those colours \n\nThe flowers and plants you link to either change colours for similar reasons. Basically, the pigment they contain in the cells predominantly absorbs different wavelengths than traditional green plants, and so reflects a different colour. "
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"https://www.google.com/search?q=plants+with+red+leaves&client=ms-android-uscellular-us&espv=1&source=lnms&tbm=isch&sboxchip=Images&sa=X&ei=T1ucVYrfNoyq-AHJnb74Aw&ved=0CAYQ_AUoAQ&biw=360&bih=559"
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2q9ito | what *is* the space that gets taken up when i add "data" to my hard drive, phone, memory card, ect., and how exactly does it work? | I really don't know how to properly explain, but when I add, say, music to my phone, what exactly happens that limits the phones capacity? The phone doesn't gain any weight, and nothing actually goes inside it. There is no physical "empty space" inside of a storage device, correct? What is causing the phone to just "not process" the data? And what does data even look like? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2q9ito/eli5_what_is_the_space_that_gets_taken_up_when_i/ | {
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"Data is stored by a specific arrangement of the physical components of the drive. For example, in a standard HDD, the data is stored as the directions of magnetic fields on billions of different locations on a coated metal platter. The surface of the platter is always magnetized, and depending on how the magnetic fields are arranged, it can represent any file that has as many bits as there are individual \"sections\" of the hard drive's surface that can be reliably magnetized (as well as some arrangements being used to mean \"no data\").\n\nSolid state storage (SSD) uses individual memory cells made out of transistors for each bit, instead. In that case, the capacity of the drive is determined by how many physical cells it has, and the data is stored as electric charge in the transistors.\n\n > And what does data even look like?\n\nNothing. At least, not by itself. Data isn't a \"thing\". It's an *arrangement of other things*. For example, imagine that you have a row of light switches that aren't connected to anything. They're just kind of *there* on the wall, and you can flip them up and down if you want.\n\nSo let's say that you have four of those switches, and you flip them like so:\n\nup, down, up, up\n\nYou can treat downs as the number 0, and ups as the number 1, so your light switches indicate:\n\n1011\n\nThat's the binary representation of the number eleven. So the \"data\" for the number eleven looks like light switches when you're using light switches to store the data. Likewise, in an HDD, data for the number eleven might \"look like\" magnetic fields arranged south, north, south, south.\n\nIn short, \"data\" is just \"using the state of some sort of system to represent information\".",
"Think of the storage as being lots and lots of switches.\n\nWhen your phone is empty, the position of these switches - whether they are on or off - really doesn't matter.\n\nWhen your phone is full, the switches are all being used to represent the photos, apps and and music in your phone. You can't install more apps, because there are no free switches to move into the right position to represent your new app.\n\nSome of the switches are used simply to keep track of what the other switches are being used for, as well as keeping track of which switches are free for use."
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33t899 | what causes rivers to suddenly be rapid in certain areas? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/33t899/eli5_what_causes_rivers_to_suddenly_be_rapid_in/ | {
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"The speed of a river is determined by a lot of factors - the steepness of the ground it's flowing down, how deep the water is, and how wide, mostly. If those change suddenly, the speed of the river can change suddenly too.",
"Think of a river like a garden hose. The water flows smoothly and at a certain speed if the end is open. But putting a sprayer (or your thumb) over the end gives the same amount of water less area to get through, increasing its pressure, speed, and turbulence.\n\nThat's what happens when rivers get suddenly shallower or narrower, or both. The old saying \"still waters run deep\" kind of captures this phenomenon as well."
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4e47f3 | how is it profitable for wineries to sell their wine cheaply enough to an import/export company that i can get it on another continent for $5.70/bottle? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4e47f3/eli5_how_is_it_profitable_for_wineries_to_sell/ | {
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"There is a world wide surplus of basic grade grape wine juice. Australia, Chile, Argentina, US all produce commodity grade grape wine juice.. Perhaps you've heard of [Charles Shaw](_URL_0_), aka Two Buck Chuck. A few years ago it was about $2 at the retail level, wholesale perhaps a dollar or less. Obviously those wines aren't made with grapes from premium areas such as California's Napa and Sonoma valley. \n\nLow grade wines don't have to have the attention to consistent flavor profiles or duration of aging that mid grade and premium wines do. A few dozen 275 or 330 gallon IBC totes is enough to fill a stainless fermenting vat, and produce several thousand 750mL bottles that are capped with inexpensive screw tops, or synthetic corks. Load it into a shipping crate, and off it goes around the world. \n\nI bet most of that $6 is middleman markup and transportation costs.\n\n"
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aanq1o | what spurred the usage of 'xmas' in place of 'christmas'? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/aanq1o/eli5_what_spurred_the_usage_of_xmas_in_place_of/ | {
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"\"X\" is the Greek Letter Chi, which is the first letter of \"Christ\" when written in Greek. The X is just an abbreviation, and was used for many years by Christians as a secret code that only others would know to show they are Christian in times when it wasn't best to be open about it. ",
"**Please read this entire message**\n\n---\n\nYour submission has been removed for the following reason(s):\n\n* ELI5 requires that you search before posting.\n\nThere are absolutely no exceptions to this rule. Please see this [wiki entry](_URL_0_) for more details (Rule 7).\n\n\n\n---\nIf you would like this removal reviewed, please read the [detailed rules](_URL_2_) first. If you still feel the removal should be reviewed, please [message the moderators.](_URL_1_?)"
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2nxyc5 | how do vegetables get vitamins and minerals if they only "eat" water and sunlight? | Where does it all come from? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2nxyc5/eli5_how_do_vegetables_get_vitamins_and_minerals/ | {
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"They also take in nutrients from the dirt. That's how you can get things like iron etc. ",
"In order to make sugars, a plant needs certain elements in its diet. It gets Carbon from the Carbon Dioxide in the air. It gets H2O from water. When it transfers in the water, it uses a tube in its stem, called the xylem. When this absorbs water from the soil below it, it carries nutrients in the soil occasionally, giving the organism certain vitamins and minerals. Of course, some plants will adapt to this, giving them a dependency or a new feeding pattern where they can mature faster with minerals.",
"They do eat other stuff than water from the dirt. Phosphorus and stuff."
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6ql1zc | what gives fire its shape? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6ql1zc/eli5_what_gives_fire_its_shape/ | {
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"When air is heated, it tends to expand.\n\nTo explain why it expands - Heat is basically the measure of vibration and movement of the actual molecules within a substance. When something is solid, these vibrations don't have enough energy to stop the attractive forces between the molecules thus they stay mostly in place.\n\nWhen something is a liquid, the molecules have enough energy to repel a LITTLE bit from the attracting forces, but can at least move so they tend to slide over one another and create something that flows - A liquid.\n\nSomething that is a gas has enough energy for each molecule that they have completely freed themselves from one another, and will expand to fill any container that they are in because they are basically just constantly slamming into one another as they move. This is what causes pressure because the molecules are constantly bouncing off of one another and forcing each other away, and WANT to move outward.\n\nThe hotter something is, the more it wants to expand as the movement of the molecules increase. Thus the lower density it would have as it expands.\n\nThis expansion lowers the density of the air that is being heated by the flame, as such it wants to rise upward because the cold air around it is more dense and forcing the hot air upward. Hot Air balloons work on this idea. \n\nSo in essence what you are seeing is not the exact shape of the fire, but what the air that is moving upward forms it into.\n\nIn space, fire would be much more stable in its shape and be mostly rounded as there is no gravity for hot/cold air to convect against.\n\n"
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1d651z | how do free softwares like vlc player make any money? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1d651z/eli5_how_do_free_softwares_like_vlc_player_make/ | {
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"Broadly speaking, they don't, but that's okay because they aren't trying to. VLC is \"community-developed\" software; it's just a bunch of people who got together to write a video player because they wanted to.",
"Maybe not VLC specifically, but a lot of them are side projects. Get the producer's namde out there with a free product, and maybe the consumer will look into their paid products",
"Some have a community of developers donate their time, others sell support service for their software etc. \n\nRedHat makes a linux distribution, but also teaches training for a healthy sum. I'm sure they have other services too.",
"Imagine, if you can, for a moment a world in which people's first thought is not 'how can I make money out of this?' but is instead, 'how can I make the world a better place?'"
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85olxj | how do air brakes work? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/85olxj/eli5_how_do_air_brakes_work/ | {
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"The air is applied to a large gasket that pushes on an acutator rod. That in turn pushes a lever attached to a rod that goes into the brake drum, the rod has a double ended cam shaped like an S that forces the brake shoes into the drum",
"They are not that much different than regular brakes.\n\nReguar brakes use hydraulic fluid. You push the brake pedel, and your master cylinder forces fluid down the brake line, and that squeezes the brake pads against the rotor.\n\nAir brakes are the same thing. You have a compressed air tank, and when you press the brake, air pressure is forced down a brake line which forces the brake pads against the rotor. \n\nAir brakes can also work the exact opposite way. In a train, the air will keep the brakes open. A reduction in pressure is used to apply the brakes. This has the advantage that if a train car was disconnected or there was a loss of air pressure, the train car or train would come to a stop. It should prevent a runaway train.",
"Air brakes are essentially regular drum brakes on steroids. Disclaimer: I’m an auto insurance adjuster, not a mechanic or engineer. I know the systems; you may not get the perfect technical language but I’ll probably describe them in simpler language. The way a drum brake works is like this:\n\nImagine that you have a cup, like a regular cup for drinking. Stick your hand into that cup, but not enough that you can’t turn it. Now imagine that cup is spinning quickly and your hand is just hanging out in there not really creating any friction with the inside walls of it. Now imagine that you form a fist with your hand and the friction between your expanded fist with the inside of the spinning cup causes it to stop spinning. \n\nIn this analogy the cup is the Brake Drum. Your hand is the Brake Shoes, and the actual skin on your hand that makes contact is the Brake Lining. In a drum brake system the Shoes and Linings are two horizontally opposed plates that remain stationary attached to a backing plate, while the Brake drum they’re inside of spins with the wheel. The Shoes and Linings don’t contact the Drum because a Return Spring keeps them tight. When you press the brake pedal, brake fluid travels through the brake lines, though the Master Cylinder and Power Booster, where it becomes pressurized, and enters a Wheel Cylinder (piston) between the Shoes and Linings, that pushes them out. They make contact with the Drum, like that fist in that cup, and that friction stops the vehicle. \n\nNow, the stopping mechanisms on an Air Brake system are generally the same with a few exceptions. Instead of hydraulic brake fluid, pressurized air is used. This is achieved much in the same way that an A/C systems work: a compressor, series of lines, and receiver-dehydrator to keep it all dry. Instead of a wheel cylinder (piston) pushing the Shoes and Linings against the Drum, a push rod activates a lever attached to a cam, which pushes the Linings out. The Cam looks like that meteorologist symbol for a hurricane, it just sits in there and turns when activated, pushing out the brake Shoes and lining against the Drum, like your hand in that cup."
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2av1ki | how does 'immigration reform" aka legalizing 11 million people and allowing for more foreign workers help create more jobs? | Bills Gates is laying off thousands of American workers yet at the same time says that we need to bring in more foreign workers. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2av1ki/eli5_how_does_immigration_reform_aka_legalizing/ | {
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"As far as I know, it doesn't. The only thing it will do is further depress wages. Simple supply and demand. \n",
"Im not sure how it creates more jobs but it should create more revenue. Undocumented individuals often CANT pay taxes because they cannot get a social security number nor a Taxayer ID number. The people who they propose legalizing are not people who just came here but those who have been here a long time and are already part of the economy. When Regan legalized immigrants they had to prove that they had been residing in the U.S. since 1981 i believe. No one is proposing opening the border to new immigrants. ",
"None of these answers are ELI5 so I will try to make one. It is all about supply and demand. Company's in USA need high skill workers and currently there is a shortage of skilled workers. They hope to attract more skilled and educated foreign workers which takes less time and money than training or educating your current workforce . At the same time there is an excess of so called unskilled workers in America who are competing for the few available jobs. Therefore American company's can be very picky in hiring and employing unskilled laborers, since there is such a large supply of them, so company's lay off workers who are not performing to their standards. "
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xisdd | what causes the static screen when you go to a nonexistent channel on your tv. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/xisdd/eli5_what_causes_the_static_screen_when_you_go_to/ | {
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"It's just noise in the electronics.\n\nIn old televisions, where you were capturing things with an antenna and adjusting with a dial, a small portion of the static at night was caused by the cosmic microwave background radiation.\n\nNumerous other more local sources contribute most of the noise."
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523jfq | how do returns work at retail stores? what does the store do with broken returns? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/523jfq/eli5_how_do_returns_work_at_retail_stores_what/ | {
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"I used to work at Best Buy. When we get a return, it goes into something called functionality check where someone checks the device for accessories or any damage/defects. If it's good, they mark it \"open box\" at a discount. If it's broken, they send it out to their service center to be repaired and then resold in the same fashion. If it's beyond economical value to repair, they send to \"PRC\" or Product Return Center which is sending back to the manufacturer for a small kickback so it's not a total loss. "
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dn3swo | how do podcasts make any money on advertising when their ads are just commercials for other podcasts? | I listen to a few podcasts from the iHeartRadio network and HowStuffWorks network. During ad breaks, most of the time it's just an ad for another podcast. Does the parent company just find these podcasts to bring up the amount of listeners and then eventually put ads for products and services? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dn3swo/eli5_how_do_podcasts_make_any_money_on/ | {
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"They also advertise other things that cost money, like Audible books, mattresses, website hosting/design, etc.",
"Casper, Hello Fresh, Blue Apron, _URL_0_, Audible... just to name a few things I've heard ads for on podcasts. It's probably just the specific podcasts you decided to listen to.",
"Less popular podcasts advertise on podcasts. These podcasts know that you listen to podcasts. Much like advertising movies in the lobby of movie theaters.",
"So these are networks so they make the most money when all their podcasts are making money. So for iHeartRadio you have a super sized podcast like SYSK and while they can make a ton of money just doing ads on that if they can get you listening to three or four of their podcasts instead of just one now reach week they are tripling their money off of you. \n\nGetting one long time listener to a new podcast (a fairly easy feat in comparison to someone buying a new mattress) is way more value per impression than the core of people who buy mattresses."
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ecjj6i | with the release of last christmas in 4k, how are old music videos that are so low in resolution remastered in 4k? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ecjj6i/eli5_with_the_release_of_last_christmas_in_4k_how/ | {
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"The original was shot in very high quality to physical film (35mm probably) and then was compressed for the media standards and capabilities of the day.\n\nThey just get the original footage and compress to 4k instead of whatever the first release was. They may haved digitally altered the colours to make it more saturated etc"
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6g1ufa | the difference between architects and engineers in the design of a project, and how they work together | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6g1ufa/eli5_the_difference_between_architects_and/ | {
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"In as simple terms as possible, the architect comes up with the design of the building/area/whatever itself, and engineers figure out how to make the design work as closely to what the architect wants. They go back and forth about what is and isn't possible, costs, etc to come up with the final plan.\n\nIn short:\n\nArchitect \"I designed this, can we build it?\"\n\nEngineer, \"Yes, but it would triple the budget. We could change this slightly to make the cost better\"\n\nA, \"Hmm, that takes away from the original design i was hoping, what about this?\"\n\nE, \"Yeah we can work with that\"\n\nEtc, more back and forth.",
"Architects work on the overall design of the building. What surface each room need to be able to fulfil the need of the client, how these room need to be located in the building, etc. They also design the exterior and are responsible to respect the code (aka exit, size, number of toilet, that kind of things). They are also responsible for the building envelop, meaning what protect the building interior for the outside (insulation, walls, windows, etc) and finally they are responsible for the interior (doors, paint, etc), they may or may not work with an interior designer for that last one.\n\nEngineer work on structural integrity. Basically, they look at the design of the architect and make it work. They get information on the composition of strength of the soil and find solution to make the building that the architect stay up. They will calculate how much weight and stress will apply to the building and design the strength of material needed to make it work.\n\nHow they work together will depend on the type of building. For the vast majority of building, they don't have that much interaction. The architect work with the client to find what he need and create a coordination drawings. The engineer will look at the drawings and design a structure and emit coordination drawings. If there is something that doesn't work with the design of the architect he discuss with him to find a solution (change the design or change the structure). Usually by e-mail, in person if there is too many problems. For bigger project there will be regular meetings during the conception.\n\nBut from time to time, the architect will want to make a non standard building. For example a stadium, a skyscraper, a large building in wood, etc. In that situation, the engineer will work with the architect from the start because a lot of design decision will be made depending on what is possible or not with the structure.\n\nSource : I'm an engineer. But keep in mind that this is how we do things in Canada, and this may differ in other country.",
"Here's a rough oversimplification: An architect is an artist. An engineer is a technician. However, architects have to understand math and physics, and engineers need to understand human interaction with their design.",
"This is a very simplistic description. Architects know a little bit about everything (structure, electrical, mechanical, civil), but specifically design. Design being defined as creative problem solving. Engineers know a lot about one thing. Architects coordinate between all the different engineering consultants after coming up with the initial concept design. "
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5uovu0 | why did competing video stores not have any issues getting all new films, yet competing online services seem to have to fight over content? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5uovu0/eli5_why_did_competing_video_stores_not_have_any/ | {
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"[First sale doctrine](_URL_0_), which was court ruling that stated that once you purchased something you could do with it as you pleased. If a video was available for sale, any video store was free to purchase it and rent it out. Studios could (and often did) release VHS tapes for like $100 at first (\"priced for rental\") to maximize revenue from video stores, and then later on drop the price to consumer-friendly levels. Or they might provide discounted pricing to preferred rental chain, ie. Blockbuster's \"guaranteed in stock\" titles.\n\nStreaming, however, works differently where the platform (Netflix, Hulu, etc.) have to buy the rights to stream for a specific period of time for a negotiated price...",
"Exclusivity costs more. The online services *want* to be the only place you can get something, because that will drive people to subscribe to them. So they enter a bidding war to get content with exclusive rights.\n\nIf they were all fine with all having the same library, it wouldn't be an issue, but then Netflix, Hulu, Amazon, etc. wouldn't have any real reason for you to choose one over any of the others."
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4fg9rz | if food contains so much energy in the kilocalorie scale, why can't we use that energy to power our homes? | We can see the nutritional value of foods sold always provide lots of energy often in the kilocalorie scale (food calorie) and if you convert that to energy values like: joules and watts, it's quite a lot!
The energy one person should eat in a day according to the officials is quite a lot. 2,000 kilocalories as said in Thailand and we know that people are getting obese because they are packing on more calories that that.
2,000 kilocalories is 8.368 megajoules or about 2.324 kilowatthours.
If food packs in so much energy and McDonalds is easy to find and packs in a lot of energy. Why can't we convert the energy in food into real energy like our bodies do it? Why can't we convert this and heat our homes and power our light bulbs? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4fg9rz/eli5_if_food_contains_so_much_energy_in_the/ | {
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"We do, its called diesel fuel. They have similar energy densities, and this is why petroleum is the most common form of transportation fuel. For stationary power plans coal is more common, but it is pretty much the same thing, a complex hydrocarbon.\n\nEdit: also Ethanol, we straight up turn corn into car fuel sometimes, but its generally cheaper to dig up crude in Saudi Arabia...",
"To release the enregy in food we would have to burn it. And there are cheaper things to burn for energy. Wood for example. But while many people still heat their homes with wood, there are a lot more efficient ways to produce energy. That is why we have power plants ;-) Additionally they are equipped with filters to reduce pollution.",
"Food contains energy in the form of stored carbon, just like coal or oil. Pretty much the only technology we've devised to extract that energy involves burning the carbon, using the heat to make steam, and using the steam to drive turbines. This is exactly what happens inside of coal-fuelled and oil-fuelled power stations.\n\nSo to turn your Big Mac into energy we'd basically need to set it on fire and use that energy to boil water. But given all the time and money that's gone into growing grass to feed the cattle to make the burger, we'd be better off simply growing biomass to burn directly.\n\nTLDR -- we *could* turn our food into electricity, but it's far simpler and cheaper to make electricity from other sources."
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1ouu48 | the bank crisis 1837 | Can someone explain to me the causes and lasting effects of it? I kinda understand that inflation went way up, but all the websites I look at use complicated terms that I'm unfamiliar with. Thanks | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ouu48/eli5_the_bank_crisis_1837/ | {
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"Cause:\n\nLocal banks receive federal bank money and loan too much paper money (not gold or silver) out.\n\nDetails:\n\nJackson hated the national bank and decided not to recharter its bill in 1832. This was the start of the BANK WAR. Jackson believed that a national bank had high interest rates and exploited smaller, western banks. The director, Nicholas Biddle, responded by calling in some of its loans early, creating a mild crisis. Jackson reacted by saying that any loan money the national bank collected would be taken away and put into local banks. These local banks received the deposits in the form of gold and silver and, as banks do, loaned it out to people who needed money. Unfortunately, these local banks loaned the money in the form of redeemable paper notes and loaned out more money than they could back with gold and silver. This caused the PANIC OF 1837.\n\nEffects:\n\nInflation, unemployment, and bank closings skyrocket. The next president, Martin Van Buren, received a bulk of the criticism even though he had nothing to do with the crisis. The panic allowed the rival party, the Whigs, win the office in the next election, which helped serve as a catalyst to the two party system we see today."
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dvrxuz | how does turning down the temperature while away from home actually save energy? | It seems to me that maintaining an internal temperature would require less energy than letting the house cool and then having to crank the furnace on high for an hour or more to raise the temperature back up to a comfortable level, assuming the external temperature is much colder than the internal temperature.
Follow up question: When the external temperature is much colder than the internal temperature, are there any energy savings in keeping the internal temperature lower, say around 17 Celsius vs 21 Celsius? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dvrxuz/eli5_how_does_turning_down_the_temperature_while/ | {
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"Heating the house back up is something of a fallacy. What you are doing is replacing heat lost to the outside. Think of it as a \"black box\". The only input is your power supply. The only output is heat escaping that needs to be replaced by the supplies you are paying for. The energy loss is a function of the difference between inside and outside temperature summed up over the day so you want to keep that as low as possible.",
" > It seems to me that maintaining an internal temperature would require less energy than letting the house cool and then having to crank the furnace on high for an hour or more to raise the temperature back up to a comfortable level, assuming the external temperature is much colder than the internal temperature. \n\nEverything I've learned about heat transfer says this isn't true. \n\nIn short, heat transfers faster when the temperature difference is greater. \n\nHeaters and A/C output a constant temperature when they're on, no matter what your thermostat is set to. \n\nThink of it this way, if it's 40 F outside and your thermostat us set to 70 F, you're trying to keep the house at a constant temperature. As soon as it hits 70 F, your heat shuts off, because 70 F to 40 F is a big difference, it loses heat very quickly. As the difference in temperature falls, the rate of heat loss also lowers. In comparison if you have your thermostat set to 60 or 65 while you're away, there is still a big difference from 60-65 down to 40 but that difference is less than from 70 down to 40, which means your house loses heat more slowly because your thermostat is lower. This means the heat doesn't run as often as if you try to keep it 70 the whole time. \n\nSo yes, it may seem maintaining a higher temperature would be better, but the actual energy required to raise the house (in winter) from a maintained 65 F to 70 F when you return, is less than the energy required to maintain 70 F the entire time. This is because the greater the temperature difference between inside and outside your house, the more often your units have to turn on, the more often they turn on, the more energy they use. While on, they use the same energy whether they are heating the house 1 degree or 10 degrees, the only difference is how long they run, and heating the house 10 degrees takes less time than heating the house 1 degree 10 times (due to how heat transfer works).",
"I turn my heat / AC completely off if I'm going to be away for more than a day. It doesn't take long or cost much to warm/cool the place when I get back.",
"How much energy your house loses at any given moment is proportional to the difference between the temperature inside minus the temperature outside. Where I am the mid-winter differential is about 40C (+20-(-20)). If I reduce the inside temperature to 15C the temperature difference drops to 35C. For the time period I keep the temperature low, I save 5/40 or 12.5%. \n\nSo if I spend $600 a year on heating, temperature setback would save me $25 a year. (1/3rd of time saving 12.5%)\n \nNow it is not quite that straight forward as the outside temperature is not constant, efficiency of your heating system might affect reheating, your system has to have sufficient capacity to bring the temperature back up, etc. And in a well insulated home, that spends less on heating overall, those saving shrink more (not as a %, but as an absolute $ amount). But the proportion of hours setback can be increased (night, daytime when no one is home, etc).",
"The energy to heat up a house a degree is constant, that is as long as the house is warmer than the freezing temperature of water.\n\nThe rate that heat leaves the house trough thermal conductivity trough the wall depends on the temperature difference. The energy loss is a constant that depends on the isolation multiplied by the temperature difference.\n\nSo the lower temperature difference the lower the heat flow from the house is and the temperature drops lower.\n\nLet's say that it is required 720 000J= 200Wh to raise the temperature 1 degree and the heat loss is 10W/(degree difference). The number is completely made up of simple calculations. So not correct for a real house but they show the principle. \n\nIf the outdoor temperature is 0 and the indoor temperature is 20 the heat loss is 10\\*20= 200W so 200Wh per hour. That is the energy required to keep the house at that temperature per hour. For 3 hours you need 3\\*200=600Wh\n\nIf you turn off the heater and simplify the calculation so the temperature only change at the end of the hour to avoid differential equation. A correct solution will show an even larger difference.\n\nThe first hour you loos 200Wh. That would result in a drop in the internal temperature of 200/200=1 degree to 19 degrees.\n\nIn the second hour, the temperature difference is only 19 degrees so the energy loss is 10\\*19=190Wh . The temperature will drop by 190/200=0.95 degrees to 18.05 degrees.\n\nThe third hour the energy loos is 10\\*18.05=180.5Wh and temperature drop is 180.5/200=0.9025 and the temperature is 17.1475 degrees\n\nTo heat up the house to 20 degrees you need to heat it 20-17.1475=2.8525 degrees and you need 2.8525\\*200=570.5Wh of energy to do that. That is lower then the 600Wh you need to keep it a lover temperature\n\n & #x200B;\n\nSo that simplified calculation shows that the energy needs to keep a constant temperature is higher than to let it drop and to heat it up again.\n\nFor the same reason, you save energy by lowering the temperature because the heat flow is lower. \nEstimation of energy-saving is (17-outdoor temp)/(21--outdoor temp) so at \n\n* 0C is 17/21= 0.81 so a reduction of 19%\n* \\-20 C ( 17+20)/(21+20)= 0.90 so 10 % less\n\nThe most extreme case is if it is 17 degrees outdoors when you need no heating if indoor is at 17 degrees but you need heating to get to 21 so the difference is infinite.\n\nReality is more complex than this, for example, the ground does not have the same temperature as the air, you have ventilation and heat is lost that way."
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5un4u1 | why don't we treat addictions by putting the addicted people into medically induced coma for a long time? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5un4u1/eli5_why_dont_we_treat_addictions_by_putting_the/ | {
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"This wouldn't address the behavioral factors that brought people to their addictions.",
"I like to think half of it is a change of lifestyle.\n\nYou can get rid of the physical addiction, but it'd probably still be on your mind because it's part of your normal day routine.",
"Because addiction isn't just a physical/biological addiction. There is a significant behavioral component. If you don't change the habits, you don't deal with the addiction....pretty much at all.",
"For the same reason that we don't imprison people for simple traffic violations: It would be overkill.\n\nThe costs alone would be more than other treatments that have been proven to be effective. So why use a nuke when a smaller/different tool works just fine?",
"* medically induced comas are expensive and cost more than the harm addiction causes\n* long term comas have very serious side effects\n* they don't treat psychological addiction\n* they don't treat the mental illnesses that lead to addiction\n* they don't treat the environment and economic conditions that lead to addiction"
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6mrg3q | shouldn't many more of us have bed bugs? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6mrg3q/eli5shouldnt_many_more_of_us_have_bed_bugs/ | {
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"Oh they are a real problem. \n\nBut they don't get around too well by riding on people. \n\nThey aren't like fleas, who are highly mobile. Bed bugs are slow and don't jump. So if you sit on a couch with bed bugs, you might pick some up, but they won't be leaping leaping onto passing strangers. \n\nHowever, when you put your clothes in the laundry basket (or on the floor) they will make their steady way into the rest of your stuff.\n\nThe best way to transfer bed bugs is by moving bedding (especially mattresses, obviously) or upholstered furniture between buildings. ",
"Those stories are very true. I just got done dealing with an infestation. Its become an epidemic: _URL_0_\nBut no, you're not just lucky. Currently, you have a better chance of having no bed bugs at all. Only around 15% of apartments currently do.\n\nAlso keep in mind that you may have bed bugs and not know it. For some people, the bites leave no marks, no itching, and no sign anything happened at all. "
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500zby | what is the difference between decibel and sone? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/500zby/eli5what_is_the_difference_between_decibel_and/ | {
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"The decibel (dB) is a unit used to express the ratio of two values of a physical quantity, often power or intensity. One of these values is often a standard reference value, in which case the decibel is used to express the level of the other value relative to this. \n\nThe sone is a unit of how loud a sound is perceived. Often times engineers and scientist refuse to use sone because many consider it to be a subjective measurement and not accurate. "
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1a1ah2 | what is the big deal about "unlocked" smartphones? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1a1ah2/eli5_what_is_the_big_deal_about_unlocked/ | {
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"an unlocked smart phone would allow you to use it on any carrier, and in the case of Europe put in any SIM card that is prepaid (or pay as you go). It means that you can have a phone that can work on any carrier and not be forced to select from the phones that they have available.\nIts quite useful for international traveling, just get a prepaid SIM and put it in, all your contacts will still be there and everything.",
"Smart phones are quite expensive and so present an entry barrier to cell phone companies who are trying to provide a service. To solve this they sell phones which might cost $800 at only $200 if you agree to a 2-year contract, planning to recoup the cost over the course of the agreement.\n\nHowever, if you can unlock your phone you could switch to a different carrier after taking advantage of the discounted price. They could lease the phones instead, but that puts them in a position of risk where people would break phones they don't own and rightly expect maintenance in the agreement. Rather than switch around their business model and hope it flies, carriers would prefer to just pass laws to enshrine their monopolies on the hardware."
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889wka | mechanical advantage | Could anyone explain me how does it become 4 times lighter in this system of pulleys?
_URL_0_ | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/889wka/eli5mechanical_advantage/ | {
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"Pulleys provide a mechanical advantage depending on how many wheels they have. \n\nThis can be explained using a few simple concepts. \n\nIf you were to tie a rope to an object (let’s say it’s a brick) and you threw the other end over a tree branch, when you pull that end, you pull the brick up even though your pulling the rope down. This doesn’t provide any mechanical advantage, but it is a single pulley system. So the mechanical advantage would be 1/1. \n\nIf you were to tie one end of a rope to a branch, then you swing the other end over that same branch, the. Attack a hook with your brick on the slack between, you have just created a two pulley system. When you pull on the remaining end, the force required to lift your brick has now been halved, and the distance needed to be traveled has doubled. By counting the pulleys you can see that you now have a mechanical advantage of 2/1. \n\nWith odd numbers of pulleys it becomes tricky, as the end of the rope must be attached to the load (like the first example), and then you need to hang the rope from the branch, through a hook on the load/object, and back over the branch. Since there is three pulleys in this system (branch, hook, branch), you have a mechanical advantage of 3/1. \n\nYou can easily expand this to a forth by tying one end of the rope to the tree, then though a hook on the brick, over the tree, through the hook again, and finally back over the tree, you now have 4 pulleys. Just like marks, you will now have a mechanical advantage of 4/1. \n\nIn this example, every time the rope went over the tree or through a hook, it was a pulley. You could actually try this pretty easily at home. \n\nI haven’t yet really explained it, so here is how it had it’s mechanical advantage. The reason you must pull the rope 4 times as far, is because excluding the length of rope your pulling, there are four strands in the system. So every inch you pull must be evenly distributed along all the other ropes. However, this also allows the force of your pull to be distributed across four ropes, essentially multiplying the force you put in by 4 this is your mechanical advantage. "
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f69j35 | why do some cuts heal quicker than others | Ever since i started working as an electrician i frequently get small cuts on my hands. Nothing serious but i noticed these cuts tend to heal a lot slower then when i cut my self while shaving for example. Can somebody please enlighten me? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/f69j35/eli5_why_do_some_cuts_heal_quicker_than_others/ | {
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"Some parts of your body, like the inside of your mouth, are \"primed\" to heal and will heal much faster than other parts. Cuts on your hands, or anywhere where the skin is constantly being stretched and bent will take longer than places where the skin is basically left alone to get on with repairing itself.",
"If you're working as an electrician, odds are that you're working a lot with copper (wires, etc.). Copper is toxic for the human body (although trace amounts of it are necessary for your body to function properly). My guess would be that your hands still have a residue of copper on them when you cut yourself or that you cut yourself on the copper itself. The cut heals a lot slower because of the toxic copper residue that got into the wound. Although copper prevents your cells regenerating it also kills a lot of bacteria that could infect the wound so the cut will heal slowly but there's generally not a huge risk of infection if you keep it clean and maybe put on a band aid.",
"While shaving, you cut yourself with something that is quite literally \"razor sharp\". This produces a clean cut which doesn't do as much damage to the tissue than a cut with something dull. Think about using a dull vs sharp knife in the kitchen: a dull knife will squash and tear the tomato or whatever it is you're cutting. The less tissue damage there is, the easier it is to heal.\n\nYou can't easily see this difference with the naked eye, but it's still a large enough difference to matter for regeneration rates. That's why surgical scalpels have an almost legendary level of sharpness, in order to ensure the minimal amount of tissue damage possible."
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51xirr | advertising with use of a competitor's name | Apologies for that bad title but I'll explain more here..
I've recently seen an advertisement for the Microsoft Surface tablet where, within the advert, the proposed user of the tablet claims they "couldn't do that with my mac".
Does Microsoft have to gain permission from Apple to do this? Do they have to pay Apple to be able to do this? I assume there's something put in place to monitor this kind of advertisement? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/51xirr/eli5_advertising_with_use_of_a_competitors_name/ | {
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"A Mac is a real thing that exists. You don't need permission to call something by its name. It's honestly that simple. "
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1jzcx8 | how come bottled water is such a hot commodity while other animals can still drink water from unfiltered lakes and rivers? | I understand that pure water = good for you, however why do we place such a high priority for it when any other mammal can drink lake water without any repercussions? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1jzcx8/eli5_how_come_bottled_water_is_such_a_hot/ | {
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"Wild animals have lots of parasites and DO face serious repercussions. There's a reason the animals in zoos live longer and grow bigger than in the wild, and it's not just that they have no predators. Try adopting a stray dog right when it arrives in the shelter; they're full of parasites and need a LOT of medicine to get healthy.\n\nAlso, you've lived your whole life on clean food and water. Your gut is full of friendly, weak bacteria, unadapted to killing off parasites. If you drank contaminated water, you'd build up some degree of resistance as your bacterial flora adapt. But even that won't save you from tapeworms and the like.",
"Animals aren't as susceptible to marketing",
"Marketing. No really, tap water is perfectly fine. Although don't try the lake thing if you are unsure. ",
"Bottled water was mostly a push by the soda companies (Pepsi & Coca Cola) to deal with soda sales that had stopped growing. It's a brilliant scheme, as it is even cheaper to produce than soda, just bottle up tap, and market to the consumer as if there's a difference to sell at rates more expensive than gasoline.",
"Some tap water got contaminated in Europe in the 1970s. Ever since then, the Europeans have primarily drank bottled water.\n\nIn the throes of the revolution that swept across New York City high society in the 1980s, restaurants began serving bottled water. Wall Street financiers were flush from the roaring bull market, and could afford to pay for bottled water that evoked European sophistication (even though NYC tap water is the most delicious shit evah). This caché, I assume, trickled down into the American mainstream. ",
"[this](_URL_0_) if you've ever had it you'll do everything you can to prevent it. Drinking untreated lake water is a good way to catch it. "
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5u5xxe | why does it always feel like there's somebody behind you in the dark? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5u5xxe/eli5_why_does_it_always_feel_like_theres_somebody/ | {
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"Most human instincts are based on a time and place when it was super dangerous to be out and about in the dark. There were no street lights or flashlights to guide the way. There was little to no protection from dangerous animals. So our subconscious evolved to pay extra attention to sensory input when it's dark out. In our modern lives it's easy to see how this can lead to lots of false positives. ",
"It doesn't feel like that to me. I love the bliss of the night.\n\nGenerally, evolution gave us a better safe than sorry mentality. Checking if someone isn't sneaking up on you is easily done at little cost to you. Facing the consequences if someone does happen to be sneaking up on you is very costly. Any impetus to make you check—especially at a more dangerous time when it's hard to see and help is less likely to be nearby—will generally be advantageous, even if the vast majority of the time nothing is there."
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9rwmgg | why doesnt earthing a connection discharge all the electricity in the circuit? | And if there need to be a completion of a circuit for current to flow, how can the earth ever complete a circuit? Even lighting isnt a complete circuit, is it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9rwmgg/eli5_why_doesnt_earthing_a_connection_discharge/ | {
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"In normal circuit operation, you need a closed loop to keep the current flowing. But that is only true in \"steady state\"; you can have short term current flow without a closed loop. \n \nAll you really need to get current to flow is a voltage differential and sufficient mobile charge carriers. If you don't have a closed loop (and an energy source), the charge flows and eliminates the voltage difference, then no more current is going to flow. There's no reason that it would. ",
"It would, if the earth ground was connected to every single component in the circuit. \n\nBut this would defeat the purpose of those components since electricity would flow from the source of voltage and out through the earth connection, rather than flowing through the components themselves.\n\nIn general, an earth connection is used to prevent metal structural parts of an appliance such as the outside casing, from becoming electrically \"hot\" if a power wire accidentally contacts them. In this case the excess current will simply be shunted to the ground, keeping the voltage on the casing to basically zero.\n\nIn electrical engineering, this is known as a \"Ground fault\" \"Residual Current\" or \"Leakage current.\" Specifically, a current that travels out through the high voltage \"hot\" prong or terminal, but doesn't return the same current through the low voltage terminal.\n\n\n An example might be the all time stupid idea of using a hair dryer in the shower. Current could potentially flow from the heating coil in the dryer, out through your body, through the bathwater, and into metal plumbing pipes. But having a direct ground connection to the chassis reduces the likelihood of this.\n\nIn any case this is dangerous since even 30-50 miliamps of leakage could cause lethal heart failure. This small of current would not trip a breaker and is much less than the appliance draws in normal use. Many outlets and breakers also have a residual current detecting circuit, designed to detect small differences in output and return current, and quickly shut off the circuit in that event."
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3i91uf | why are some people able to survive huge falls while some die instantly from much smaller ones? | Vesna Vulovic survived a fall from 33,333 feet. There are people that fall from apartments windows, much lower down yet they often die. Is it just down to how they land? Or something more complex? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3i91uf/eli5_why_are_some_people_able_to_survive_huge/ | {
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"A mixture of extreme luck and what you land on. If its concrete your dead, if its grass or dirt you have a very small chance of bouncing a few times breaking lots of bones but still potentially surviving. Human terminal velocity is 120 mph (your top speed in a free fall) so just think about the different types of materials that you could hit in a 120 mph collision and survive.",
"Certain parts of your body are much more important if you want to stay alive than other parts. For example if you fall 5 feet and land on your head, the force of that fall might cause a small fracture in your neck or other part of your spine. Because the spine carries nerves, even a small fracture can damage the nerves you need to breathe or move at all. This can easily kill you.\n\nOn the other hand landing on your feet from 5 feet up is unlikely to hurt you at all, and if it does a fractured ankle won't kill you.\n\nAnother factor here is that the neck is actually easier to injure than the legs or feet-- this is pretty much because the legs are meant to be the ones on the ground and the neck is not supposed to be there. Injuries of this kind are not common enough for humans to develop tough necks when they usually don't need them.\n\nHead injuries are also very nasty. Breaking the femur, which is large bone in your leg, can also kill you because of the internal bleeding that huge injury causes. But most other bones in the limbs are not life-threatening if you get medical care. So it's partially about what part of your body gets hurt. "
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7o4q5u | why does perception of color change after taking off ski goggles? | I was out shoveling in the snow storm that hit NYC wearing red-pink ski goggles. When I came back into the house and took them off, everything had a greenish hue. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7o4q5u/eli5_why_does_perception_of_color_change_after/ | {
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"The brain automatically tries to balance our perception to a reasonable white balance which means a tinted lens or lighting will be compensated for given time. But once they are removed it also takes a while to adjust back.\n\nUltimately this tendency probably goes back to some very basic functions of nerves which reduce response to repetitive sensations.",
"Your brain handles \"white balance\" the same way a camera does, in that it recognizes an artificial tint and \"normalizes it\" so that a white object viewed through an orange lens still registers as white to your brain. When you take the lens off suddenly, it takes the brain a little while to re-calibrate for the difference in colors.\n\nYou can notice the same thing when it comes to different light sources. If you are indoors around dusk, you can look around your house with the lights on and see things as \"normally\" colored, but if you look out the window, everything outside looks very blue. The outside isn't actually lit by blue light, it's that the light in your house is very orange, and your brain has corrected for that color cast. ",
"Your eyes have special cells called Cone Cells that give you the ability to see color. You have three types of cone cells - S (short wave), M (medium wave), and L (long wave), but for the sake of simplicity, we'll respectively call them blue, green, and red. (Fun fact: The absence of any or all of these cone types are what result in the different types of color blindness).\n\n\nNow when you wear your snow goggles, the rose colored lenses are effectively blocking all of the visible light and only allowing the red color wavelength to pass through and reach your eyes. AS a result of this, your red cones are detecting the red light while the other two cone types are essentially in the dark. After awhile, your eyes will become adjusted to the condition while wearing the rose goggles. Once you go back inside and take off your goggles, your green and blue cones will suddenly be bombarded with light, as if somebody quickly opened the curtains in a pitch black room. From the blue and green cones' perspective, everything will appear much brighter while your red cones don't notice any difference at all. As a result, your mind will see the blue-green color wavelengths much more clearly and overshadow the red color wavelenth and make everything appear a greenish blue hue. This will continue until your green and blue cones become acclimated to the light and balance everything out."
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5gngc3 | why can't you pay for gift cards with a credit card? | I get the redundancy of it. You're basically transferring money from one card to another. But why is it not allowed as opposed to not being recommended? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5gngc3/eli5_why_cant_you_pay_for_gift_cards_with_a/ | {
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"At some stores, the 2-3% bank charge on a credit card transaction isn't worth it. Let's say you buy a $100 gift card with your credit card, the store only gets $97.50. That's losing $2.50 up front, and usually the reason you can't get cash for unused gift card balances.\n\nThat said, I bought several as gifts this weekend with my credit card, at merchants that figured they'd lose that money when they take a credit card for merchandise. So you can pay for gift cards with credit cards in some stores.",
"I'm not sure what you mean. I've bought plenty of gift cards using a credit card, and recently too, since it is the holiday season.",
"Gift cards are a common avenue of fraud. \n\nWhat happens if you steal a purse and want to steal money from the person? You take the cash from the wallet but these days it probably isn't much. So now you try to use their credit cards before they are cancelled.\n\nSo what do you buy? You don't want to race out to Macy's and buy a bunch of clothes because what you really want is cash for rent, alcohol, and drugs. Instead you buy a gift card with your stolen credit card, and sell that gift card below face value somewhere such as online. By the time they figure out the transaction was fraudulent and revoke the gift card the thief is long gone with their cash. \n\nIf the store has been burned a few times that way they can just refuse to sell gift cards on credit.\n\n\n\n\n\n\n\n\n",
"Gift cards, especially to major businesses (such as grocery stores) have a second-hand market very close to purchase price, and can be resold relatively easy without much worry about being caught. Many other goods are difficult to quickly resell for any appreciable value. In places where card fraud is prevalent, many businesses restrict the purchase of gift cards. \n\nIf I were a criminal with a new batch of CC stripes, I could easily go around buying $50 gift cards, turn around and sell them off for maybe $40, do this a few times on that one card and then ditch the number, and pocket the cash.\n\n"
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cki7ls | what is a motif in music? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cki7ls/eli5_what_is_a_motif_in_music/ | {
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"Your motif is part of music that's repeated to invoke a specific emotion or feeling in a musical piece.\n\nI'm some styles of music a motif will come back always the same to create familiarity, In other pieces a motif can change a little bit every time it comes back so the motif develops like a character in a story."
]
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[]
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||
3uu5lh | why do astronauts wear white? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3uu5lh/eli5_why_do_astronauts_wear_white/ | {
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"Astronauts wear white to reflect sunlight. Otherwise the spacesuit would get too hot and the person inside could be in serious danger, or even die, from being too hot. One layer of the space suit is called the [Liquid Cooling and Ventilation Garment](_URL_0_) which also helps the astronaut from getting too hot.",
"To reflect heat.\n\nAlthough we hear about space being very cold, in fact it is difficult to lose heat in space due to the lack of any substance to transmit the heat to. The only way to get rid of heat is through infra-red radiation, which takes a long time.\n\nThe problem is that astronauts generate body heat faster than they can get rid of it, so much that they have to have cooling fluid pumped around their spacesuit. \n\nSo the last thing you want is the spacesuit and occupant also warming up due to exposure to the sun, hence the suit is white."
]
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"https://en.wikipedia.org/wiki/Liquid_Cooling_and_Ventilation_Garment"
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||
2tlhls | whatever happend to kony2012 and why isnt there something similar for boko haram who's actions have been much worse? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2tlhls/eli5_whatever_happend_to_kony2012_and_why_isnt/ | {
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"Probably because Kony2012 didn't do anything. ",
"If I recall correctly, there were two main reasons why the Kony 2012 hype quickly died down:\n\n1) People who were actually familiar with the situation spoke up and basically said the Kony issue was no longer relevant / significant anymore and they had no idea why this guy was trying to start the campaign\n\n2) The director of the campaign was caught publicly masturbating shortly after Kony 2012 started to become a thing and this news (which made a lot of headlines) mostly discredited the campaign",
"Remember #saveourgirls ? That was about Boko Haram. We sent advisors to help find them, but things didn't work out because the Nigerian army was found to be too corrupt and incompetent to work with. It's no longer a hopeful or good-news story.\n\nThere are anti Boko - Haram activities going on all the time in Africa. That group has lost some battles and many soldiers.\n\nBut what else would you expect to hear about it? It's not big news in America. You have to search for it & find the details in international news. \n"
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fblc3y | why does vasoconstriction lead to better blood flow? | I keep reading, as a science student, that when blood flow or pressure goes down, arterioles constrict in order to raise blood pressure. But vasoconstriction actually increases resistance, thereby depriving the tissue further of blood flow.
So what is it that I'm not understanding? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fblc3y/eli5_why_does_vasoconstriction_lead_to_better/ | {
"a_id": [
"fj4zlnr"
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"text": [
"Vasoconstriction does not increase blood *flow*. It increases blood *pressure*. If all things were equal, that would normally increase blood flow. But as you note, making the blood vessels smaller increases the resistance to flow. \n \nIf you grab a hose or piece of tubing with liquid flowing through it and squeeze, the upstream pressure rises due to the resistance you've added. But the rate of flow goes down."
]
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[]
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|
79fbf6 | why are "girl" pushups so much easier than regular ones? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/79fbf6/eli5_why_are_girl_pushups_so_much_easier_than/ | {
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"There was an r/askscience post that blew up a couple days ago about what percentage of you body weight do you lift up while doing push ups. \nIIRC: Knee push ups had a smaller percentage, meaning you were pushing up less weight. \n\nEdit: Provided by u/crnaruka\n\n“Your question made me curious and a quick search yielded the study linked below, which looked at exactly this question. The researchers found that the answer depends both on the variant of the exercise as well as the stage of the exercise. For example, in a traditional push-up the number is about 69% in the up position (at the top of the movement) and 75% in the down position (bottom of the movement).\n\nIt's also worth mentioning that the study also looked at a \"modified push-up.\" This modification [as shown here](_URL_0_) is essentially just an lazier easier version of the exercise where the knees stay on the floor. Surprisingly (to me at least), even in this simpler version you still lift quite a bit of your body mass (54% in the up position and 62% in the down position).\n\n[Link](_URL_1_)”\n\nFormatting is shitttt, I’m on mobile ):\n",
"Think about a spanner. It is much easier to turn a nut if you pull on the spanner at the far end, rather than near the nut. Forces which cause rotational motion are called moments (also called torques), and the distance from the point of rotation matters.\n\nNow when you do a push up the man way (from the feet), your centre of mass is further away from the pivot (your feet) than it is for girl push ups (from the knees). This means gravity induces a stronger moment on your body when doing a man-pushup, hence it is harder to fight against it and \"do\" the pushup.\n\nWhen going from the knees, you have shortened the distance between your centre of mass and the pivot, which weakens gravities' moment on your body, which means you have less resistance to pushup against."
]
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"https://i.imgur.com/2PagQIv.png",
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||
3kgh0w | how long does holy water stay holy? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3kgh0w/eli5_how_long_does_holy_water_stay_holy/ | {
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"Any water blessed by a priest is Holy Water. \n\nIt's mostly used for anointing something. We would dip our fingers in Holy Water and do the sign of the cross when entering and exiting mass, for example. People get baptized in holy water, or the priest would splash holy water on the congregation during certain ceremonies.\n\nGenerally, you don't drink it. You're not supposed to. There's nothing that says anything special or bad will happen to you if you do drink it, though- from what I remember.\n\nI remember a child drinking holy water once in church, and everyone thought it was just a cute kid thing. He wasn't cast out and called a heathen. \n\nNo, it wouldn't be \"holy urine\" when you peed it out.\n\nI honestly don't know about diluting it. I would assume it just wouldn't be considered holy water anymore.",
"I believe you are taking it too literally. \n\nHoly water is water that has been blessed by a priest to be used in various traditions (baptisms, holy cross when entering church, etc). \n\nHoly Water should only be disposed through regular use, or by disposing of it in a special container. I would imagine that using holy water to water plants, diluting holy water or drinking holy water would fall under the \"improper disposal\" category.\n\nThat being said, there is no holy water police, so traditions may vary from family to family and region to region. ",
"Like all religious things, it comes down to faith. Catholics believe the water to be holy because a priest blessed it for use in special rituals. Obviously it's not like the water went through some molecular transformation and I'm sure you know that. \n\nI think you are probably trying to poke fun at this matter of faith (and as an aetheist myself, I understand the urge) but it's considered holy as long as the people who believe in it consider it holy. Tautology! \n\nIt doesn't do shit to vampires because they don't exist. Your plants won't grow any better or be more blessed, and your half & half holy water would probably be thought of as now being unholy just because you are fucking around with it.\n\nIt's like the idea of the wine becoming the blood of Christ. How long does it stay bloody? The premise itself is outside of faith. "
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25fcpw | is it possible for humans to choose their own personalities? | This seems a bit philosophical… There is no limit for age of the individual (early adult/later in life). I am just curious in general.
Does the individual have agency in personality change?
Any personality psychologists out there?
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/25fcpw/eli5is_it_possible_for_humans_to_choose_their_own/ | {
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"There are some things you can't change. For instance, I am a very anxious person. I don't like that about myself, but I can't just stop being one. With a lot of personal effort and some counseling, I will become a slightly less anxious person, but it's still a root element of my personality that can't be chosen or unchosen. I imagine everyone has some aspects like this."
]
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|
5nua75 | is there a science behind photographers telling us to say cheese? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5nua75/eli5_is_there_a_science_behind_photographers/ | {
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"The \"eeeeeeeeeeeeee\" bit results in a kinda-natural looking smile. And everyone knows that word, it's a very common word with a drawn out long e sound.\n\nIf you tell people \"make a natural smile\" you get everything from \"not a natural smile\" to \"please dont eat me.\" "
]
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||
e7scmc | what is pencil tip made up of? lead or graphite or both? why? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/e7scmc/eli5_what_is_pencil_tip_made_up_of_lead_or/ | {
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"It contains no lead at all. It's made of graphite. The term \"pencil lead\" is only a reference to graphite's color, which is similar to lead's color.",
"There is no lead in pencils. Rather, the core is made up of a non-toxic mineral called graphite. The common name “pencil lead” is due to an historic association with the stylus made of lead in ancient Roman times.",
"There's no lead, it's a mixture of graphite and clay. The graphite makes the mark, and the clay is mixed in various proportions to alter the hardness of the pencil."
]
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9yhdqh | when you're awaiting surgery why will they not even let you have a glass of water if you're thirsty as hell? why aren't all the iv fluids quenching the thirst anyway? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9yhdqh/eli5_when_youre_awaiting_surgery_why_will_they/ | {
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"If you throw up while you’re asleep you can choke to death. IV fluids are all salt water, they keep you hydrated but don’t keep you from getting thirsty.",
"You can't drink anything because there is a chance you may regurgitate whatever is in your stomach as your body's reflexes are stopped while under anesthesia. If regurgitation happens whatever is in your stomach is pushed back up into your throat and mouth which you could accidentally inhale, causing you to suffocate or it can make its way into your lungs and cause pneumonia or something similar. The reason the IV doesn't quench thirst is because thirst is usually a feeling of your mouth being dry and your brain being triggered by this causes a feeling of being thirsty. So you can be hydrated and still be thirsty at the same time. ",
"When giving you anesthesia one of the major issues is people throwing up and, by virtue of being unconscious, breathing in their vomit into the lungs. That is a very bad thing, potentially deadly, and reducing the amount of fluid in the stomach reduces the danger. "
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acfjrs | how do locks and keys work when it comes down to uniqueness? is every lock-key combination unique? or could i get lucky and could i find another door or bike lock that matches my key? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/acfjrs/eli5_how_do_locks_and_keys_work_when_it_comes/ | {
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"Great minds think alike. I may have found yer answer, matey. Yer not alone in askin', and kind strangers have explained:\n\n1. [ELI5: Is each lock and key combination unique, or do I share the same house key as a bunch of other people? ](_URL_2_) ^(_83 comments_)\n1. [ELI5: How are keys unique? There must be millions of doors out there. Do \"overlaps\" happen? What are the odds that my key will open a random door in the same city? ](_URL_3_) ^(_18 comments_)\n1. [ELI5: if every lock is unique and requires a different key to open in, how does a skeleton key open any lock? ](_URL_0_) ^(_6 comments_)\n1. [ELI5: is every house key completely unique? How is this done? ](_URL_7_) ^(_11 comments_)\n1. [ELI5: Does every single car in the world have a unique key? ](_URL_8_) ^(_37 comments_)\n1. [ELI5: How do padlock companies make so many locks, yet ensure that your key only opens your lock? ](_URL_4_) ^(_43 comments_)\n1. [How are there enough variations for keys that every key in the world can only unlock it's specific lock? ](_URL_1_) ^(_18 comments_)\n1. [ELI5: How do lock makers mass produce locks that can only be opened with one key? ](_URL_5_) ^(_12 comments_)\n1. [ELI5: How are locks/keys made so that no other key works in any other lock? ](_URL_6_) ^(_8 comments_)\n",
"Locks have a set of pins. These pins have a break in them. Keys lift the break in the pins to line up with the barrel of the lock allowing it to rotate. Rotating the barrel then moves the bar of the lock out of the way. Typically a lock will have 4 pins, but there is no limit. I've seen single pin locks and dozen pin locks. \n\nSo is every combination unique? No. I have a masterlock with 4 pins, it looks like each pin has 10 possible break points, meaning there are 10^4 possible keys for that lock. If they've sold more than 10,000 of those locks there are duplicates out there. \n\nIt gets more complicated though -- keys also have a shape. You can't just put any key in any lock. Some keys are round, some are straight, some are dimple based....then there are the fancy locks that have discs not pins.\n\nThen as locks get old the tolerances get looser. You start finding that keys that didn't used to work start working on a lock. Eventually even a simple screwdriver will turn a lock. ",
" > **Is every lock-key combination unique? Or could I get lucky and could I find another door or bike lock that matches my key?** \n\nMost key-lock combos are unique, but there are some exceptions. Many locking file cabinets use the same key or one of just a few keys, as do a lot of those intercom/security panels on buildings that require a code to get in. There are some YouTube videos about physical penetration testing that give more information.\n\n & #x200B;"
]
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"https://np.reddit.com/r/explainlikeimfive/comments/3omzyv/eli5_if_every_lock_is_unique_and_requires_a/",
"https://np.reddit.com/r/explainlikeimfive/comments/1vb1ev/how_are_there_enough_variations_for_keys_that/",
"https://np.reddit.com/r/explainlikeimfive/comments/2zkuvz/eli5_is_each_lock_and_key_combination_unique_or/",
"https://np.reddit.com/r/explainlikeimfive/comments/18pgm6/eli5_how_are_keys_unique_there_must_be_millions/",
"https://np.reddit.com/r/explainlikeimfive/comments/2j3gpc/eli5_how_do_padlock_companies_make_so_many_locks/",
"https://np.reddit.com/r/explainlikeimfive/comments/36a6b2/eli5_how_do_lock_makers_mass_produce_locks_that/",
"https://np.reddit.com/r/explainlikeimfive/comments/4rtx5c/eli5_how_are_lockskeys_made_so_that_no_other_key/",
"https://np.reddit.com/r/explainlikeimfive/comments/2rzqx3/eli5_is_every_house_key_completely_unique_how_is/",
"https://np.reddit.com/r/explainlikeimfive/comments/76jzx3/eli5_does_every_single_car_in_the_world_have_a/"
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70mzfk | why is there such a loud sound when we clap? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/70mzfk/eli5_why_is_there_such_a_loud_sound_when_we_clap/ | {
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"You're compressing the air between your hands rapidly, creating a pressure wave. Which is, you know, what sound is.\n\nThe best, loudest claps involve cupping your hands to trap more air between them. Your hands squeeze that air together before it rapidly expands again out through the gaps between your hands. That rapid compression and expansion is the sound wave that your ears detect. The more air you compress, the faster you compress it, and the harder you compress it, the louder the sound will be.\n\nCompare that to, say, clapping with wide open hands, palm against palm, and you won't get much of a sound, not matter how hard you clap, especially if you can get the heel of one palm into the center of the other so very very little air is trapped. You'll get a smacking sound, but that's mostly the sound of your skin smacking and vibrating the air, rather than a good solid compression of air like in a proper clap."
]
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1d76ak | why does lettuce, the white part, get all brown and slimey? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1d76ak/eli5why_does_lettuce_the_white_part_get_all_brown/ | {
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"text": [
"It's residue from bacterial decomposition. Basically, the lettuce is going bad (rotting). "
]
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||
7bw706 | why is it seemingly impossible to sync your blinker with the car in front of you? even if it's the same make/model? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7bw706/eli5why_is_it_seemingly_impossible_to_sync_your/ | {
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"(This may not be true for all cars, but it has been on the cars I've owned). The on/off blink timing for your turn signals isn't controlled by a chip, its controlled by an analogue circuit that uses the relative resistances of the lights/lamps in it. And even if you get the timing right with the same make/model car, no two light bulbs are identical, so the resistance of your two sets of lamps isn't going to be identical. \n\nHave you ever noticed that when one of your side or signal lights goes out, the blink on that side goes faster? I'm driving around right now with a busted running light and the signal blink on that side is about 50% faster than the other."
]
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fzujof | how can people with alzheimers/dementia remember to speak and understand, for the most part, general conversations - but can forget things like their children, to eat, basic personal hygiene, etc? | Are these memories held in different parts of the brain? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fzujof/eli5_how_can_people_with_alzheimersdementia/ | {
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"Things like speech and understanding are impacted as well, but they are distributed in the brain over many neurons, not necessarily in the same spot, so they are easier to access even with impediments. Specific memories will tend to be localized and it's more likely that the disease can block or destroy them.",
"One doesn't \"remember\" to speak and understand, as in that it is not a memory. Language is a cognitive function in itself, as is memory, and it can also be impacted by dementia. The deterioration of language functions that is associated with dementia or other neurodegenerative illnesses is called Primary Progressive Aphasia. Dementia affects memory first, usually, but it can also impact other cognitive functions and it definitely affects language, but it's often not as early in the progress of the disease and it's often the more complex processes of language that can go away first, hence going undetected for longer."
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66o562 | why do athletes get heart attacks? | I've known of two professional athletes that have died of a heart attack in the last few days. Both past their prime but definitely not old either and still fit (retired from competitive sport). why would someone still very fit get a heart attack? If anything id have thought professionally fit people who look after their diet and exercise regularly would be less likely to get cardiac arrest. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/66o562/eli5_why_do_athletes_get_heart_attacks/ | {
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"Exercise and activity is good for your body and for being fit, but athletes by definition go much farther than the state of being fit with the activity that they do. As such it is not uncommon for them to over tax their hearts and lungs, and if they have any kind of damage or defects that can prompt a heart attack. \n\nMany athletes also use various chemical and herbal aids (some legal, some not) to help them in their training and development and some of these aids can cause heart attack as well. "
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2nm49l | if somebody shot a gun directly at you, how far away from the shooter would you have to be to realistically jump out of the way of the bullet in time? | I realize it also depends on the kind of gun. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2nm49l/eli5_if_somebody_shot_a_gun_directly_at_you_how/ | {
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"When I was in the army, we were taught to count a second for every three hundred metres (meters, for the american audience), when estimating how far away a shooter is. If you knew exactly when the shot was fired, you'd probably need about 600m to get out the way.\n\nYour problem is that you've no reliable way of knowing when the shot is fired, as with most rifle rounds, the sound of the gun will arrive after the bullet does.",
"Mythbusters did this. Because most bullets travel faster than the speed of sound, you would be hit before you knew the gun was even fired. No dodging possible.\n\n_URL_0_",
"A German TV show tested it but there is no translation: _URL_0_\n\nIn the end I think the result was about 2 seconds on 1000meter / 0.625mile with a sniper rifle.\n\nAs mentioned by /u/glyttch it depends on many factors for example speed of your projectile, reaction time, ...",
"You cant. That's why we have guns and not bows and arrows any more :)",
"There are just too many variables with this. It depends on what you're shooting the gun with. Is it a cannon, a bow, slingshot, or another gun? They all affect how fast the gun can travel. Also what kind of gun is it? A pistol and machine gun travel through the air differently.",
"The type of ammunition is actually one of the most important things. A 22 short is a very slow round as are certain shotgun loads. These travel well below the speed of sound. If I recall 22 shorts travel at something like 500 fps where the speed of sound is around 1100 fps. Nobody is going to be shooting at you with 22 shorts though. What is possible is someone shooting at you with subsonic ammunition. Most rounds have a subsonic variant, the use of these rounds varies but a common role for these subsonic rounds is in the application of a suppressor. This combination can make some rifles almost silent and impossible to see the muzzle flash from. \n\nTechnically you can easily move out of the way of a bullet if shot from 300 yards with subsonic ammo. Problem is you would never know when the shot was fired, even if you had a magnified line of sight on the shooter. The bullet would reach you at almost the same instance as the sound. This is a best case scenario. \n\nThe only scenario i can think of that would actually allow you to dodge a Bullet is if you were being shot at by some artillery. Due to the massive blast of an artillery piece you could see the artillery fire a mile or so away and then book it away from where you were. This of course is not how modern artillery works. Artillery is almost always hidden behind something and firing beyond the line of sight. \n\nSo no, you will pretty much never be able to dodge a bullet . ",
"Great question! It depends on the speed of the bullet, which is affected mainly by the casing, but also by the style of bullet (hollowpoint vs. FMJ, percent lead makeup, etc), the type and amount of powder used in the load, the type of rifling in the barrel of the gun, the barrel length, not to mention atmospheric conditions (physics is hard!). For general purposes, a \"slow\" bullet would be a .45 ACP, which actually travels just under the speed of sound. A \"fast\" bullet would be something in a magnum rifle class, such as a 300 Win Mag round, which travels around 3,000 feet per second. There are specialty rifle rounds which travel upwards of 5,000 or 6,000 feet per second, but we're not going there because we want to talk about dodging the bullet! \n \nThe best case scenario is obviously a slower round, such as a .45 ACP could theoretically be dodged not only by having the proper magnification to see the trigger being pulled (muzzle flash or with a scope), but also by hearing the bullet and then dodging. Assuming a light .45 ACP load which causes the bullet to fire at 800 f/s or about 550 mph, the absolute time to dodge with visual warning would be 6.5 seconds at one mile. As sound travels that distance in just over 4.5 seconds, almost a full 2 seconds would be available to a person to dodge the bullet with auditory warning alone. The .45 round would need some serious tilt to travel this distance, and it would be ridiculous to try and shoot someone like this. More likely, one would be firing a round that travels at 3000 f/s out of something like a 300 win mag, which travels much faster than sound, but at one mile gives you a second and a half to dodge with the benefit of visual forewarning. \n \nEDIT: I'm assuming the time of light travel to be 0, as it is negligible with these small distances.",
"A .45 is a \"slow\" bullet, relative to most other rounds. It's so slow that it is -almost- perceptible as it goes down the range. Almost in the sense that your eye can detect something, some sort of movement, but even then, you can't truly see anything more than a sliver of a steak. So no, I don't think you could dodge a bullet, not in the sense that you could see the bullet and dodge, as opposed to seeing the gun and reacting to the idea that someone was getting ready to fire it. ",
"Assuming you're fighting at dusk or night and the enemy is using tracers, you could feasibly dodge fire around 800m. Bullets only travel so fast, and if you've ever seen night-fire exercises or, more rare, dusk combat footage, you can see just how slow they really are at these ranges. \n\n\"Jump\" is a very specific way to dodge fire anyway; maybe you only need to stick your head back down or roll over.",
"Mythbusters did this. Under controlled circumstances 500m (provided you know the instant the bullet leaves the barrel). Under \"normal\" conditions you cant see the muzzleflash over 200m distance and the bullet travels 3 times the speed of sound....\n\nFYI They used a sniper rifle in the 30cal range since less powerfull weapons would not reliably hit the target at that distance.",
"You would have about 1 second time to move if a bullet was fired out of the barrel of a gun roughly 950 feet away. A .45 caliber round depending on brand travels around 900-1000 feet per second.",
"Let's assume for a second that you know, instantly, that the bullet is about to be fired. Ignore, for the moment, all the problems with this assumption. \n\nA bullet moves about approximately 770 MPH, which is about seven times faster than a hockey puck shot by an NHL player at its fastest. Many NHL goalies (among the quickest reflexes of any athlete) can flash out a part of their body and meaningfully move their position enough to make the save when a puck is shot at this distance from between 5m and 10m away. \n\nExtrapolating, we could say that somebody with extremely quick reflexes could, in theory, get out of the way of a moving bullet if it's fired from between 35m and 70m. This would include the time required to process the shot being taken, provided you were expecting it (as NHL goalies expect the opposition to shoot but try not to react until after the shot is taken). \n\nUnfortunately, for this to be useful, you would have to be carefully watching the shooter and know, based on his finger position, when the trigger has been pulled. You aren't going to hear the shot in time and you are unlikely to see the flash. If you wait until you see the recoil, you have given up valuable reaction time. The further away, the harder it is to see the finger move. \n\nIt's more or less absurd, therefore, to think that you can dodge a bullet from any distance if you wait until the shot is fired to react, even if a professional athlete can move quickly enough to get out of the bullet's way if it is fired from the other side of a football field, assuming no delay in warning. "
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cffyeh | where and how do mountains, rivers, forests, and deserts form? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cffyeh/eli5_where_and_how_do_mountains_rivers_forests/ | {
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"Generally speaking mountains form in one of two ways.\n\nThe primary way is due to plate tectonics. The surface of the Earth, the continents and sea floor are broken up into a series of plates which sit on top of the mantle which is made up of liquid molten rock. As a result the plates are in constant but very slow motion. When the plates suddenly jerk and move we get an earthquake.\n\nWhere the thicker and tougher continental plates meet the thinner and weaker oceanic crust, the plates heave over each other. The Oceanic plates subduct (go underneath) the continental plates which causes the continental plates to be forced up creating mountains.\n\nThe second way to make a mountain is through volcanism. Hot molten rock finds a way to punch through the crust of the earth spewing onto the surface creating a volcano. Over time this volcano erupts numerous times, causing molten rock to pile up to form a volcanic mountain. These are most prominent in the ocean because the oceanic crust is thinner and weaker.\n\nMountains and the continents themselves are what cause forest, deserts, and rivers to form.\n\nIce forms at high altitudes from rain falling on mountains. This melts creating the sources of rivers. Rivers will then flow downhill and across the ground until they reach an open body of water like the ocean. Rivers are also fed by smaller streams form fromed rain water collecting over a large surface area.\n\nDeserts often form due to mountains. Moist air from the ocean travels over land, but when it reaches mountains it is forced up. This causes the rain water to fall on the mountains, so by the time this wind reaches past the mountains it is hot and has no moisture left. In time this forms a desert.\n\nBut mountains can also cause create an area rich in moisture due to the rivers they spawn, which can form a rain forest like the Amazon."
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6ofrt5 | what happens to the newly "dead" bacteria on your hands after you use hand sanitizer that "kills" bacteria? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6ofrt5/eli5_what_happens_to_the_newly_dead_bacteria_on/ | {
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"They are still there just dead. This reason is why antibacterial soap doesn't work as well as it sounds it should. Washing your hands actually removes bacteria from your hands, it may not kill it but it is a very effective method of sanitation for that reason. ",
"Like another poster has said, you can't really wash off the dead bacteria because water acts differently on them due to their size. \n\nAlso when you use antibacterials, the area will quickly become repopulated with bacteria from your environment, other parts of your skin and by the bacteria that wasn't killed multiplying. \n\nAs the area becomes repopulated, the new bacteria will use the dead bacteria as a food source. In essence, the dead bacteria becomes food for the still living bacteria. \n\nEdit: words - silly phone predictive text. ",
" > I'd prefer not to have bacteria corpses on my hands, thanks.\n\nThe irony here is that the human body contains just as much bacteria as our own cells. Not only that, but we are desperately dependent upon the bacteria that lives on our skin to protect us from all sorts of nastiness.",
"So basically using germ-x is a waste of time and it's better to wash your hands?",
"[Excellent answer from a few months back.](_URL_0_)",
"The super bacteria feed on the corpses of its weaker brethren. It makes them stronger. We are only feeding the itty bitty beasts",
"Hand sanitizer kills bacteria by lysing cell membranes. You are quite literally cutting them open and spilling their juice all over you. By rubbing your hands together there is mechanical removal of bacteria, to some extent, but your best bet is to wash under water with soap. The soap will help lyse the cell, and allow the bacterial remnants to become suspended in water. Then, they should slide off, as running water does. ",
"Objects can be made \"bacteria-corpse\" free with depyrogenation using gamma irradiation. Pyrogens are bacteria fragments left over after cell death.\n\nYou cannot be depyrogenated, because you have bacteria that live with you all the time. They eat the dead ones when they find them, and they keep your outsides happy and healthy. If you lost them, you would end up with all kinds of horrible side effects because your microbiome (or personal bacteria ecosystem) is just as much a part of you as your own cells are.",
"don't worry, the dead bacteria will be very quickly eaten by the bacteria that survived, bringing forth a mini revolution of stronger hardier bacteria.\n\nYes, you read that right. Hand sanitizers are bad for you and the world we live on.\n\nNever use hand sanitizers unless you've just touched something you are pretty sure had something contagious on it, or if you yourself have a contagious bacterial (viruses won't care about alcohol) illness and are about to cook for someone. In those cases, having less bacteria on your hand for a brief period is actually beneficial.\n\nBest way to stay healthily clean? soap. It'll get rid of the brunt of the gunk mechanically, not leave any corpses behind, and most importantly not give preferential treatment to the worst bacteria.",
"I'm sure someone else has already said it, but you're covered in and surrounded by dead bacteria all the time. Don't worry, you're used to it.",
"So i had to remove the top reply in this thread. I know people are going to want to know why, and my explanation is buried there.\n\nIt was a copy and paste of [this comment by /u/TheTimeNotTheMiles](_URL_0_). That is one of the reasons that the OP of the removed comment didn't respond to anyone.\n\nThat violates our [rule #3](_URL_1_) explicitly. I think though that it violates the spirit of rule #1 as well. \n\n\n---\nI'll post the contents of that original comment here for convenience.\n\n > So lets say we have a scalpel, right? Simplest medical device there is. There's a number of ways to make it totally(ish) sterile- gases, steam, dry heat, gamma radiation.\n\n > But as you ask- the little bacterial corpses are still there. Waiting, one presumes, for tiny necromancers.\n\n > The problem occurs when you stab someone with the scalpel, preferably in a medicinal way. The bodies immune system works by identifying certain chemical triggers in bacteria, and has no way to know that, for example, the lipopolysaccharide hanging around in someone's heart is not part of a bunch of living bacteria, but the floating corpses of dead bacteria.\n\n > The dead byproducts of bacteria are called \"pyrogens\" because they cause (among other things, such as death) fevers.\n\n > Where do they go? Nowhere. Bacteria are small enough that water has completely different properties on their level. Beyond rinsing off gross matter and reducing bacterial load, washing can't do much.\n\n > So for things like heart surgery scalpels, there will usually be a second step of \"Depyrogenation\" This is the process, not of killing bacteria, but of removing the bits left behind so they don't trigger an immune reaction. This varies widely in complexity depending on what you have to depyrogenate- steel scalpels are easier than an injectable drug, for example. Typically, the goal of the process is to so thoroughly break down the biological material left behind.\n\n > **Are my hands covered in bits of dead bacteria?**\n\n > No your hands aren't covered in dead bits of bacteria. They're covered in happy, healthy bacteria.\n\n > **Then why wash my hands??**\n\n > Washing your hands removes dirt and debris that carry the nastiest bacteria. Sterilizing your hands is a ridiculous notion however- your hands are made of cells, bacteria are made of cells. Anything that would kill them would kill your cells. Your hands, and literally everything else on the world not currently under direct gamma radiation bombardment, are covered in bacteria,\n\n > Quick run down on terms:\n\n > \"Cleaning\" a medical device is basically doing dishes-getting blood n bits off the reusable ones. (plz dont reuse single use medical devices that makes regulatory professionals sad 😭)\n\n > \"Disinfecting\" is using chemicals to get something purty darn clean.\n\n > \"Sterilization\" is killing all* the germs on something\n\n > \"Depyrogenate\" is taking bacterial corpses and reducing their remaining structure to a point where your immune system won't recognize it and freak out.\n\n > *SALx10-6 is the typical sterility level for a medical device. one in a million germs/one in a million devices\n\n---\n\nEdit: I'm going to unsticky this as i think this and my original removal reply are visible enough on their own by now.",
"This reminds me of a Harry Hill joke where he memed about not using mouthwash to avoid having a mouthful of dead germs.",
"What was the explanation? I clicked on this to see what the answer was. Can anyone repost the answer and properly cite the source? I am really curious. "
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4bxdcd | why do our eyes "burn" when they are red? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4bxdcd/eli5_why_do_our_eyes_burn_when_they_are_red/ | {
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"Red eyes usually mean there's a degree of inflamation going on. During inflamation, several chemicals are released and they cause blood vessels to become swollen and they become visible. Burning and Itching sensations are transmitted through unmyelinated nerve fibers that can be easily stimulated from those chemical I mentioned before."
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2pl6uv | how did they make glass 1,500 years ago? | Referring to the post on the front page about the discovered mummies:
_URL_0_
There were glass artifacts dug up, how did they manage to make them without modern tools and machines? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2pl6uv/eli5_how_did_they_make_glass_1500_years_ago/ | {
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"You just need a really hot kiln.\n\nIf you can make iron things you can make glass.\n\nGlass isnt hard to make."
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"http://www.livescience.com/49147-egyptian-cemetery-million-mummies.html"
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3l0lrt | how can a color blind person correctly name previously unseen colors when wearing enchroma glasses? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3l0lrt/eli5_how_can_a_color_blind_person_correctly_name/ | {
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"My guess is that they already know what color the object they're looking at is, but can't see it correctly.",
"Just a guess but I would assume they have been told their whole lives what objects are purple and they see different shades of colors for purple. So when the put on the glasses, prior to, they know it's the \"purple\" they see prior to putting them on. So after the glasses are on, they see the new color as normal vision would see it but know what the color is already.\n\nHopefully that helps.",
"Colorblindness isn't black and white.\nIt's not \"I don't see purple\"\nIt's a shades thing, some Greens look more red, some purples look more blue.\n\nThe enchroma seperates the wavelengths of light that is close together. It doesn't make purple appear, it makes the red more distinct / separate from the blue light.\nThis makes the purple more vibrant. What was a dull, mostly blue color is now a vibrant purple.\n\nWe know what the colors are, these glasses just help in making them \"better\" and stand out",
"By the time you're an adult, you'll know that grass is green, whether or not you can see it. It's just one of those bits of knowledge that everyone at some point will be told. \n\nIf you put glasses on and can now see that grass is a colour you've never previously been able to see, that won't stop you knowing that colour is green. ",
"It's just a matter of mapping some visual input to a label.\n\nI see largely in continuous grey, lacking cone receptors in my eyes. I learned to map what I see (the ocean or grass) to certain labels (blue or green). Colors that were not widely used when I was growing up (and learning \"colors\") are total mysteries to me. So, for example, I struggle with teal when it's presented to me."
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63es0h | why does zalgo text seem to display everywhere regardless of localization? | I'm talking about t̠͚̺̝̠̤̟h̜͙̤i͏s̵ ̞͇̝k̛̗͉i̭͕͓̻̲ņd͍̼ ͍̮o̙̯̬͔͍̗̝͜f̘͕̠͕͕͓ ͙̘̠̖̞̠b̘͝i͕̲z
I understand that they're combinations of "stacked" characters. What I don't understand is that it seems to break localization restrictions. Take a phone messaging service - why are the combined characters able to go beyond the speech bubble, above and below? Is it simply because no one actively prevents it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/63es0h/eli5_why_does_zalgo_text_seem_to_display/ | {
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"Zalgo text takes advantage of tricks built into unicode. \n\nUnicode is a standard for how text in all the world's major languages should be handled. It includes support not just for the latin alphabet but quite a few writing systems, including ones where text goes in other directions than left-to-right. On modern computers and technology, supporting unicode is pretty much required if you want your device to be usable globally.\n\nUnicode has some characters built into it that aren't \"real\" letters, but indicate \"this next symbol goes above/below the previous one\" or \"this next stretch of text is vertical, not horizontal.\" It's intended for languages where that happens... but if you cram a bunch of those characters together you can get weird effects like the zalgo text.\n\nBecause unicode just changes how characters are arranged, it can't really be used for glitches or code exploits, so nobody loses sleep over \"if I try really hard I can make this messaging app look weird.\""
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733jpf | why do (most) americans reject cars with a manual shift stick? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/733jpf/eli5_why_do_most_americans_reject_cars_with_a/ | {
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"1. Automatic transmissions are price-competitive here (and in many models the auto is actually cheaper).\n2. Gas prices in the US have historically been very low by European standards. So the gas-saving nature of a manual wasn't as big a selling point in the US.\n3. We drive big cars on busy roads, and we drive them *a lot*. Commuting 3+ hours a day is not unusual in America. That much time on a stick shift in traffic is no fun at all.",
"There used to be good reasons to drive a manual shift car (regarding getting good gas mileage), but that's really not an issue these days. The margin is so small that people would rather not have to deal with it.\n\nSo if you are given a choice of manual or automatic, it becomes \"why not automatic?\" And the only legit answer to that question is price (it adds about $1500 to the price on most cars).\n\nMost automatic cars made in the last 10 years can also still manually shift, without the use of a clutch.",
"Automatic transmissions are what most people here learned on and they won't know how to drive stick. These days, advanced auto trans with 7+ gears tend to be more fuel efficient than manuals, and many cars don't even come with a manual option due to slower sales.\n\nAutomatics began taking over simply because of the nature of stop and go traffic - people drive everywhere, cities in the US are far more spread out than cities in other parts of the world, and manual transmissions are a hassle when you treat your car like an appliance that gets you from A to B. I own a manual car myself but I take my automatic into san francisco in the (rare) times I have to drive in there, because manuals in stop and go traffic suck and any sort of mistake causes unnecessary clutch wear.\n\nAt this point in the game, manuals are fully in the realm of the 'enthusiast option' as they no longer present advantages to the average joe consumer"
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bi1ddn | how are artificial color dyes made differently from natural color dyes? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bi1ddn/eli5_how_are_artificial_color_dyes_made/ | {
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"Natural dyes are made by taking something that's the right color and processing it into a dye.\n\nArtificial dyes are made by putting generic, commodity chemicals into a chemical reaction process that ends up with a dye."
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2gw40r | what did roger goodell do to cause such an uproar for him to resign? | I'm from London, and so not a lot of talk about Goodell here, but all I see on reddit is that he should resign, but not much of why. Any explanations will be appreciated. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2gw40r/eli5_what_did_roger_goodell_do_to_cause_such_an/ | {
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"He is the commissioner of the NFL and a lot of people are angry over how he handled the domestic violence controversy plaguing the league right now.\n\nRay Rice was allowed to stay on the team and play while the issue played out in the legal system. There was a lot of uproar over this and Rice has since been deactivated and let go from the Baltimore Ravens.",
"much of it because of a tape that eventually \"leaked\" to the press, through one of the websites, I think TMZ not sure. The tape showed Rice punching his wife and knocking her out cold in an elevator. Before the tape was shown to the public, there was no real outcry, although some concern, the basic concept was that he has to have his day in court first. And of course this concept has been play for many years in many sports, the problem has played out many many times in the last few decades. Its pretty standard to wait for a legal decision. \n\nOf course, Rice did get a legal decision, it was some sort of probation if I recall, and the league gave out a 2 game suspension as some sort of comparable punishment. (the league has rarely handed out any stiffer suspensions for any sort of criminal activity. I want to say never, there was some information released on this but rare or never has punishment exceeded this.) \n\nAlso, tangential, but part of the big picture, a St Louis Ram player Leonard Marshall had been found guilty of manslaughter for killing someone while driving drunk and he continued to play. This happened some years ago. Also last year, a New England player: Aaron Hernandez was arrested and held on murder charges, the evidence looks very bad against him. And then there was Rae Carruth a few year before that, he had his pregnant wife killed in a murder for hire, he's in jail. And then there was OJ Simpson 20 years ago. \n\nSo there is a large back story to all this. \n\nAnyhow, after the tape was shown, the outcry became immense because it is visually disturbing or perhaps for whatever reason. A few days after the tape was broadcast an anonymous police official told the media that he had sent that tape to the league, and even got a telephone call to verify that it had reached the league. He played the tape of the call to the press to prove it. But sending a police tape, part of an investigation to another party is dead wrong.\n\nBut the knowledge of the tape seems to be what got people most upset at Goodell (your own opinion may vary0 saying that Goodell had seen the tape he should have suspended Rice, because dont we all agree on how bad that is?\n\nAnyhow, I would stick up for Goodell on certain points. His league received criminal evidence from an anonymous source. How are they supposed to treat that? In all fairness, they should refuse to acknowledge it. That stuff should not have been sent them to and they should not be able to look at it and judge Rice. \n\nTHis sort of thing is happening a lot recently. THere was a scandal in Illinois when the governor Ryan and his wife who was a tv star, had some sort of sex tape leaked that was supposed to kept under seal. There was also the name of major league baseball players linked to PEDs in the Mitchell report that was supposed to be secret. But some jackass feels that it has to be out there. \n\nSo I can see Goodell's legal position on the tape; they just cant acknowledge stuff that is supposed to be secret and even worse when it comes from anonymous sources. But try to explain that to the public. "
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dvzfnp | how do children acquire word meaning? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dvzfnp/eli5_how_do_children_acquire_word_meaning/ | {
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"Tell someone to pick something up and make up a word. boom. They pick up a \"rock\" nah, that's a gangalafuck.",
"Most of it is context and repetition. You see a dog, you point at the dog, you say \"dog\". Your kid associates all things that shape with being a dog. Then you repeat that a million times a day for everything you see.\n\nWith other words, like \"what is that?\" They learn from our tone, and from what we leave out of our sentence. You see a dog, you point at a dog, you don't say \"dog\" so your kid says it for you. You get excited, they know they've succeeded.\n\nPlus listening to people talk normally helps them figure out what order words go in."
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1m718d | how do employer personality assessment tests work and how could someone possibly fail one? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1m718d/eli5_how_do_employer_personality_assessment_tests/ | {
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"If you're applying for a sales position (or any customer-facing position), but your personality test indicates that you're strongly shy and introverted, they might consider that a \"fail\". It's not a judgement of you as a person, just an evaluation that perhaps you may not have the disposition to be well-suited for the position in question.",
"You don't \"fail\" personality tests. They are supposed to show whether you are a good match for a position. If you were non-confrontational, you might make a poor security guard. If you were extroverted, you might make a poor researcher.\n\nAs for how they work, not everyone agrees that they do, and their use remains controversial. The often will ask you questions like \"which of these do you prefer?\" or \"What best describes you?\", and give you options to choose. After enough questions, trends emerge that are supposed to give insight into your personality."
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80hfk7 | if the sun and moon are both visible (and well above the horizon), how could the moon still have a shadow? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/80hfk7/eli5_if_the_sun_and_moon_are_both_visible_and/ | {
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"About half of the Moon is always in shadow, just like Earth. The lit side of both spheroids is the side facing the sun. The only time we can't see that shadow is when the moon is on the exact opposite side of the earth from the sun. ",
"The moon's shadow is the side that isn't lit by the sun. It's not a place where the sun's light *would* shine, but is blocked by something else. \"Shadow\" is a bit of a misnomer. Half of the moon is in \"shadow\" at any given time, including when it happens to be visible alongside the sun.",
"Grab a tennis ball and a lamp. Turn off every other light in the room. Hold up the tennis ball. Half is lit, half is dark. If you are looking from the side (you can see the lamp and the ball) you can see some of the dark side of the ball. \nThe ONLY way to see nothing but lit ball is to have the lamp directly behind you, with the ball just outside your shadow. EVERY other angle that you look at the ball will expose some of the dark side."
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72xnok | why are polygons in 3d modelling software by default triangles/rectangles (pentagons & up) | title is sort of vague, but I've worked in a few 3D modelling programs and while you can have as many vertices to one polygon as you please, and even make your own shapes, but they are by default only made as triangles or rectangles,
(excluding circles.) I've always wondered why instead of using less vertices, and polygons to make something like a pentagon or hexagon, they will default to using 1 triangle, 1 rectangle, or 2 rectangles. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/72xnok/eli5_why_are_polygons_in_3d_modelling_software_by/ | {
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"Any polygon can be divided up into multiple, adjacent triangles without changing the vertex count. Math for interacting with 3D object can be quite complex, but it can be made much simpler if you know that every face is a triangle. You write code to test points against triangles and you can use it on any mesh of triangles. So algorithms for things like collision detection, occlusion, and shading can all rely on the same math equations. And the hardware can be optimized to do this kind of math in parallel.",
"Triangles, as the simplest polygon, are the easiest to process and draw. You don't have to worry about weird cases where the vertices aren't all in the same plane, producing some sort of curved surface - an issue as soon as you go beyond 3 vertices. Edit: plus they have the useful property that they are always convex (all interior angles less than or equal to 180 degrees) which makes some geometric calculations easier, e.g. viewport clipping and ray-polygon intersection. Once again this property is not guaranteed with more than three vertices.\n\nGraphics cards are also heavily optimized to deal with triangles; if they even accept more complex polygons, there's a good chance they're converting them to triangles under the hood anyway.\n\nIt keeps everything simpler all round just to work with triangles.",
"Polygonal modeling isn't actually the only type of modeling, though it's probably the most common in games. You have NURBS/NURMS which modeling that is based off of curves. Nurbs is more common in product design. You have surface and patch modeling and sub-division modeling where you're making a cage and sub-dividing with tessellation to generate the surface. You also have parametric solid modeling typically CAD that's based around actual machining proceses.\n\nThat being said, polygonal modeling is dominated by triangles today because the process is optimized for a triangle. A triangle is simple form of a mesh. You can just as easily make a \"nGon\" in Maya, which is a polygon made of n sides.. usually more than 4. The problem with nGons when applying a blinn type smoothing algorithm that makes surfaces appear to be smoother but without adding geometry is that you'll often get poles or pinches in the smoothing. Game engines, especially older engines relied on these types of geometry smoothing algorithms to improve visual quality, which makes it bad modeling practice for games. Gaming optimisation is centered around cutting surface counts as well as limiting draw calls, which makes breaking every piece of geometry down to a series of triangles means using the least amount of verts and surfaces as possible and knowing where the lines of the two Tris that make up a quad are allow for better topology when volume for animation (example, laying out your quads very specifically when creating a human face to mirror the muscular structure). If you're making nGons, then how the geometry bends to the animation could make unintended pinches and transitions.",
"Triangles are the \"atom\". You can divide everything into triangles, but you cant divide it further. So, it becomes a practical common ground for every part of the system to work with. Having one basic shape means that you can focus optimizations heavily on that.\n\nAlso, as soon as you get more than three points, they can be on different planes. Take a piece of paper and lift two corners, creating a \"valley\". Now, flatten the paper and instead hold it high and bend down the lower corners, creating a \"ridge\". Now, from the same corner positions (coordinates), you've created to completely different shapes. Say that you wanted to trace a ray of light through what you interpret as a valley (or fly a cruise missile through it), and it actually was a ridge, that wouldn't give the intended result.",
"Imagine a perfectly square piece of paper, lying flat on a table. The square has 4 corners, and if you imagine that 3 of the corners are attached to the table, and you start pulling the 4th corner away from the table, then the paper would fold. You would end up bending the original flat square into two triangles.\n\nNow think of a pentagon, with its 5 corners, and you attach 4 corners down to the table, and then pull on the fifth. Once again you'll cause a bend in the original shape, this time creating a triangle and a quadrilateral.\n\nNow take a piece of paper cut into a triangle, and attach 2 corners to the table. Pulling the third corner will not cause the triangle to bend into other shapes. You still have one entire triangle. In fact if you move the other two corners around as well, you will still always have just a single triangle with no bends.\n\nMathematically, this is because, when working in 3 dimensions, it takes exactly three points to define a flat surface (\"plane\"). Any more points than that, and you can no longer guarantee that the surface created by those points is still flat.\n\nAnd having perfectly flat objects to render makes the math needed to draw 3D objects on a 2D surface as fast and reliable as possible.\n\nWhen games and other software draw things that look curved, generally this is done as a lighting effect. Older games look angular and chunky because they didn't have enough processing to perform lighting calculations on every pixel of every triangle, causing the underlying edges of the triangles to show through. These days, graphics cards perform a crazy number of lighting calculations on every pixel drawn, so a gradient of colors across an otherwise flat triangle gives the illusion of a smooth curve without any edges."
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1d6a20 | when does it stop being an homage or reference to another great work and cross over to becoming plagiarism/stealing copyrighted works? | I often hear stories about how certain movie or TV show lines are references to other movies/TV shows. How come these are okay, when I doubt that the writers tracked down the original creators and asked permission to use those lines? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1d6a20/eli5_when_does_it_stop_being_an_homage_or/ | {
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2wjdju | why is a 'swiss bank account' such a bigger thing than other countries bank accounts? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2wjdju/eli5_why_is_a_swiss_bank_account_such_a_bigger/ | {
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"Someone explained this a long time ago to me. IIRC, it has something to do with Switzerland's odd banking policies. People who want to evade taxes or hide their money (especially if it was made shadily) put their money in a Swiss account. Even if they get in trouble in their own country, their government can't seize the money due to the Swiss laws. ",
"Switzerland has very strict privacy laws regarding banking - it is illegal for a bank to reveal the identity of an account holder. It also has a very stable economic and political position which means it is generally a safe place to keep your money.\n\nEDIT: the court can order the bank to reveal the identity of an account holder if it is deemed necessary. This includes account holders from overseas.",
"It's not \"bigger\" and it's not just for rich people, lots of people have swiss bank accounts. here are a few reasons:\n1) Laws make your info private, no one will know your account exists.\n2) Swiss economy is stable and your money is safe\n3) Swiss currency is stable and somewhat protects your money from inflation. Example if you deposited $20,000 in 1980 in a USA bank, that would have been a quite decent annual income for that time. but withdrawn today, you'd be at the borderline poverty level in terms of annual income. So your money actually de-valued.",
"Can anyone ELI5 how this relates to Nazi gold? I thought that those accounts were just recently disclosed and there was some plan to return the money to the families of the jews murdered during the Holocaust...",
"The answer is that they aren't, not anymore anyway, but everybody knows what you're talking about when you say \"Swiss bank account\" which means that people keep using the term. \n\nSwitzerland has recently rolled back their bank secrecy laws, mainly due to the immense pressure put on them by the US and Europe (they want their taxes), making it much less appealing to people with money to hide. Those people have moved their money elsewhere and there are still many places around the globe that are eager to accept money of dubious origin (\"Sunny places for shady people\").\n\n\"Swiss bank account\" as a term is here to stay, even though it now refers to a no questions asked philosophy more than something located in the country of Switzerland.\n\nCome check out /r/MoneyLaundering if you're interested!",
"The Swiss used to be able to store your items without scrutiny, but recently they're becoming more and more obsolete ",
"During WW2, the Nazis appropriated bank accounts, and made it illegal to move money out of the country (and out of their reach). People moved the money anyway, and Switzerland was a favored destination. Nazi investigators would travel to Switzerland and bribe bank officials to reveal the names of Germans who had moved money (who they would promptly execute). The Swiss government learned about this, and passed laws making it a crime to reveal banking details so that the bribed bank officials could be prosecuted.\n\nLater, criminals discovered that these laws were convenient for concealing their ill-gotten gains. Swiss bank accounts became synonymous with shady money. Foreign governments began pressuring the Swiss to reveal more banking account details to them so they could more easily discover and prosecute tax evaders and other criminals. The foreign governments threaten to cut Swiss banks out of the international financial system. This is a potent threat, and so the famous Swiss banking secrecy has eroded over the past few years.\n\nOther countries have stepped in to fill the void.",
"To REALLY answer your question, \"Swiss Bank Accounts\" AREN'T a bigger thing than other countries bank accounts. \n\nThey WERE, however. And the reasons have already been outlined here I imagine. Swiss banks were regarded as an extremely safe place to store funds discretely. All that changed, however, upon the U.S. investigation into UBS clients a few years back. To be perfectly honest, it's been changing for years at this point.\n\nMy former boss did have banking arrangements with UBS but it was one of four now global banks that his arrangements were with that runs the gamut from Citibank (U.S. based) to Barclay's (British based). The fact of the matter is that nowadays it matters precisely not at all whether your assets are located in a Swiss based bank. There is no tax advantage, no privacy advantage, and certainly no rate advantage (UBS was never competitive with either time deposits or currency exchanges.) Swiss banking is really on the way out as Ultra HNWIs don't see the benefit of them anymore.\n\nWhat has replaced the Swiss banking arrangement has been the Cayman Islands Holding Corporation, the Luxembourg Limited Parternship, or BVI companies. My former boss is a Greek citizen but because his holding corporation is based in the BVIs and he resides in Monaco, he paid nothing in taxes on either his holding corporation or individual level in 2014, a year in which he earned and deposited apprxoimately £300 million in various accounts. There was no preference given to Swiss banking except as a means of diversification.\n\ntl;dr: Swiss banking is not a bigger thing than banking in other countries anymore",
"Long story short: they ~~don't~~ didn't snitch!",
"Several years ago the US Gov't had a huge lawsuit for them to give up 5000 accounts suspected in criminal investigations. They fought it tooth and nail and ended up giving about 5%. ",
"The Swiss have NO ETHICS whatsoever. Swiss banks gladly accepted the illegal seizings of the Third Reich... the property of millions of Jews, including the gold from their melted-down teeth fillings. The Swiss basically covered their eyes and ears and said \"bring us your Nazi gold... we'll keep is safe for you and won't ask any pesky questions about where any of it came from! Wink wink!\"",
"I don't know why it would be now, but one of the things that was very important earlier. Was the Swisses ability to remain neutral, in past wars. And where would you rather likely be putting your money? In a bank that can survive a \"catastrophy\" or a bank that is very likely to be conmdemned bankruptcy because of a war?",
"Swiss banks use Switzerland's privacy laws to hide money for criminals.",
"Secrecy. \n\nSwiss banks were notorious for keeping information of their depositors away from foreign tax collectors (among many other national agencies). And while they did have to report any suspicious transactions, rarely did they provide information about their customers who had presumably committed tax fraud in their home country. This was largely in part due to the Swiss' narrow definition, where non declaration of income and assets was only qualified as tax evasion, which was not a crime according to Switzerland. \n\nThere were many law suits by the U.S. against UBS (a Swiss bank) in 2008 to 2011 involving the OECD (US Organization of Economic Cooperation and Development) and the G20 (UN group of 20 nations) to require member states (including Switzerland) to \"provide information about foreign taxpayers as long the requesting country provided prima facie evidence that they had violated the requester's domestic law.\" (Switzerland: Foreign Pressure and Direct Democracy by Julio J Rotemberg and Jonathan Naharro Martin[requires Harvard Business Review subscription])\n",
"People who use the term \"anonymous numbered Swiss bank account\" don't know what the hell they're talking about. Swiss accounts have never been completely anonymous. Swiss banks want to know as much about the client as possible so they can provide the best service possible. The point of a \"numbered account\" is to protect the privacy of the holder from low level bank employees. Only senior bank executives have access to the holders identity and those executives are often barred from leaving the country for fear they will be arrested and forced to divulge bank secrets. After 9/11 the US came down hard on international banks, as a result their impenetrable wall of privacy is mostly gone. The banks have changed focus from asset protection and privacy to providing higher returns with lower fees. \n\nIf you want a truly anonymous account you have to go through a process called 'layering'. This involves setting up a large network of shelf companies and trusts through multiple jurisdictions in places like Panama, BVI, Nevis, Belize, Cyprus and Hong Kong. The money is then routed through the companies in several different ways to obscure the source. This is how despots and dictators hide their money. There are a number of shady law firms that specialize in layering. \n\nYour average wealthy family can easily avoid taxes and protect their wealth through some straight forward and completely legal means. Trusts are a wonderful thing. \n\nTL:DR; Banking privacy is gone, rich people don't need to break the law to avoid taxes. \n\nSource: Family has Swiss accounts, as do friends families. ",
"It's not anymore. It used to be because they were super secret and wouldn't tell anyone else about your money, but now Swiss banks roll over for the US government like other banks.",
"Because, the moment you mention you have a Swiss Bank account, you get the chicks.",
"The best response is that it's purely a perception issue. As SZ was one of the most stable and favorable banking regimes around, and also had the most stringent secrecy laws about disclosure, a Swiss bank account used to be the preferred vehicle for hiding money overseas and not reporting income to the US federal government. There are also stories about drug dealers, terrorists, despots, etc. keeping tons of money in these accounts, using them to launder money, that kind of thing. There is a (from the US perspective) social stigma associated with having one. It implies that they are attempting to dodge taxes.\n\nWith the recent changes in legislation (and some momumental political black eyes), the Swiss have enacted some transparency to their banks. Whether it's real or window-dressing is an open question, but it seems to be resulting in some cases of tax fraud being located.\n\nIs it a 'bigger thing' than other countries? Nope. For instance, the Cooke Islands has incredible stringent banking secrecy laws, no interest in changing, and is a preferred place to launder money/evade taxes. It's just the average guy on the street hasn't heard about them.\n\nSwiss bank accounts don't currently deserve their social stigma, though at one time they most certainly did.",
"Because until recently they would take money from absolutely anyone. The mistake they made was helping americans evade taxes so now they can't do that anymore. But it remains the destination of choice for dictators, corrupt politicians, criminals and other non-americans with ill gotten wealth to hide. Switzerland has gotten fat off money siphoned by third world politicians. They come into power with the help of the American CIA and steal with the help of Swiss banks.",
"You're going to hear a bunch of fluff about privacy, but what it boils down to is tax evasion by foreign account holders is not prosecuted nor does it result in frozen assets, and the Swiss bankers who abet them are held harmless in the process.\n\nAll you'd have to do is charge less than the marginal tax rate on the investors next dollar. As you can imagine, this is insanely profitable for both the Swiss banker and the tax evader.\n\nEdit: wording",
"Tax avoidance.\n\nSwitzerland operate on a *neutral* footing - they try to not align to any particularly nation, ideas, interests.",
"Because Switzerland is the fiefdom of the ancient banking dynasties, look at their flag, what does that look like? Where did that symbol come from? What is that related to? What else does that flag grant people?(entry into any country in the world and a global network of logistics and support - \"the red cross\" - a permanent \"observer\" status at the UN). Why are they neutral in every conflict yet extremely well-armed and trained as a society? How do they make it so everyone sends them their money?\n\nIt's a place that's part of something greater that has happened throughout world history and commercial history. It's a sovereign state controlled by bankers, for bankers. The bankers don't enter the conflicts(they merely fund and payroll both sides) so no one will ever enter the country and seize the funds held there because the people in power on both sides have their personal funds held there, and the Swiss claim neutrality. It's a stable place in Europe based on ancient treaties and banking dynasties/sovereign military orders, so they can make their own laws and hold their own without being interfered with by external legal or military entities.\n\nLet's say it's just a place that has been run by smarter people than most places have been for a longer period of time.",
"Huguenots (French Protestants) escaping persecution in France came to Switzerland and basically created modern banking there in the 17th century. Most industries that have a long unbroken history built up through generations of continued development are almost always leaders in whatever sector they find themselves in. \n\nThat is, it's no accident that the Swiss banking sector is as successful or respected as it is. ",
"Confidentiality and neutrality, coupled with legitimacy. It's extremely difficult and time-consuming for foreign (non-Swiss) government investigations to actually ferret out a paper trail with regards to the contents of your Swiss bank account, and there's very little that they can do to freeze it: they would need evidence of wrongdoing that is normally almost impossible to attain without the very information that they're trying to acquire through the banks. Meanwhile, so many legitimate enterprises use the Swiss banking system--including said foreign governments--that nobody wants to simply go after them and force them to change the way they do business. ",
"It's not. In case you hadn't heard, the Swiss have *negative* interest rates. That's right, the bank charges you to keep your money there.",
"I'm living and working in Switzerland.\nOne update to what's already in the topic.\n\nIf you hold US passport, it's now damn difficult to open even simple current account for salary (if you're US citizen working in CH).\n\n\nAnd don't forget, that from certain amount, interest is negative. You have to pay money to save them in Switzerland.",
"Swiss lawyer here: Until recent years swiss banks were not allowed to give away any kind of informations considering bank accounts, no matter what.",
"It means nothing to an American nothing now. The Swiss don't accept new US customers, and are throwing out existing customers because they don't want to deal with US regulations. It used to be a safe place to park money with no questions asked. Not anymore.",
"Swiss economy is very stable. So it is very safe to keep money in Swiss Bank, especially for the rich. They securely store billions of dollars in Swiss bank. As they are a stable economy, there is no chance that there will be a bankruptcy or something like recession affecting Swiss Bank.\nThe privacy is also very high. You can't just withdraw your cash. You need to show your passport and other documents to prove that 'you are you'. This lets the rich to hide their money and evade tax in their native countries.",
"\"Name-less\" bank accounts are the holy grail of tax evasion. If you can deposit money in there and not have it traced back to your identity, you can essentially live a tax-free life. The hard part is wiping away the finger prints to your identity. You essentially could do this in Switzerland, Bermuda and certain other jurisdictions until recently when governing bodies believed it would be in their best interests to disclose the information."
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6dnu84 | how do farmers make sure that no fertilized/developing eggs make it to market? | I assume hens and roosters aren't put together, but especially for free range, I'm sure at some point a rooster and hen must have found a way to get frisky | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6dnu84/eli5_how_do_farmers_make_sure_that_no/ | {
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"Eggs can only get fertilized when there are roosters around to fertilize the eggs. No roosters, no fertilized eggs. So the way farmers make sure that no fertilized eggs get to the market is by separating them from the chickens.\n\nNow the tricky thing here is that farmers also need fertilized eggs to grow new chickens to replace to older ones. Half of the chicks born are female, whereas the other halve are males. This isn't so much a problem for the chickens that are grown for meat consumption (both are eaten). However, roosters are useless for the production of eggs. So most roosters are killed early on.",
"Most egg processors \"candle\" each egg, shining a bright light through it. If there is something growing, it's not sold. Roosters aren't common at egg farms, as chicks are sexed early in life and the boys that live are destined to be part of the meat cycle.",
"Most hens are not raised near roosters. Even free range. But they do check the eggs. They do so with a method called candling. This is where you shine a light through the egg and look for the embryo. In olden days this was done with an candle by eye (thus the name). In modernity it is done with bright electric lights and cameras in an automated process. It is possible that some get through, but even that is not an issue since eggs are washed and chilled quickly after being harvested which stops development. ",
"They separate the roosters from the hens when old enough to determine sex of chick... a pen of egg laying chickens won't have any roosters.",
"I worked for a turkey producers and visiting the hatchery was fascinating. \n\nThe sexers look at the vents of the poults and determine, with a 98% success rate, whether it's a stag or hen and throw it into a chute. Depending on what the farms are placing depends on what sex is more desirable. But it was usually Hens that were needed more. \n\n50k poults could be hatched per day and there was pretty even split of male/female. 52/48% I believe. Every time. \n\nThe unwanted, deformed, dead in shell poults then go off to the gas stunner and then to the IMD (Instant Mechanical Destruction) \n\nIt's brutal. "
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16q17m | what does java do for the computer? | With the problems with having to disable it, I'm just wondering. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/16q17m/what_does_java_do_for_the_computer/ | {
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"Java is an environment that programs can run in, kinda like Flash Player.\n\nWithout Flash Player, you cannot watch Flash animations or play Flash games. Similarly, without Java, you can't play Java games or use Java programs. (Minecraft is a Java program.)",
"The big thing about java is that it is a language that lets you run the same program on multiple OSs. You know how you can't take a Windows program and run it on a Mac? Well, you usually can if it is developed in Java. The java client on your computer allows it to run the java code and converts it so your PC can run it so they just need different client versions for the different operating systems."
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qxadu | - xkcd comic #1028 | I don't really understand [it](_URL_0_). Does this mean I'm bad at communicating information to others, or understanding pictorial array's attempts at communicating? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/qxadu/eli5_xkcd_comic_1028/ | {
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"White hat sees a dangerous trench, tries to warn others verbally. \n\nShort Hair and Woman don't understand (or at least don't pay attention to) the danger until they experience it for themselves by falling in the trench.\n\nMeanwhile, Woman's seen a similar danger in the other direction; she tries to warn White Hat, who is too busy assuming Woman will warn Short Hair about the first trench to pay any attention, and falls in the second trench.\n\nWhen Beret sees the danger, rather than simply telling No Hat about it, he takes him and shows him first-hand; No Hat understands immediately.",
"Just gonna throw this out there for future reference: _URL_0_",
"Panel 1 - Hat Guy sees a hole in the ground. \nPanels 2, 3, 4 - Hat Guy tells Hair Guy. Hair Guy doesn't understand, and Hat Guy gives up trying to explain. \nPanels 5, 6 - Hat Guy tells Girl about Hair Guy not understanding him. Girl tells Hat Guy about a different hole in the ground. Neither of them understand one another. \nPanels 7, 8, 9 - Hair Guy and Girl encounter one another. They tell each other about Hat Guy, and walk off. \nPanels 10, 11 - Hair Guy and Girl are too busy thinking and talking about Hat Guy that they fall down the hole that Hat Guy was trying to warn them about in the first place. And at the same time - \nPanel 12 - Hat Guy falls down the other hole that Girl was trying to warn him about. \n\nMeanwhile -\n\nPanel 13 - Beret Guy sees the hole in the ground. \nPanel 14, 15, 16 - Beret Guy encounters No Hair Guy, and asks him to follow back to where the hole is. \nPanels 17, 18 - Beret Guy *shows* No Hair Guy the hole. They leave both knowing about the hole. \n\nMoral of the story - show, don't tell.\n"
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803vxi | why do you feel unsafe when limbs are sticking out under your blankets? | And why does this not apply to your head? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/803vxi/eli5_why_do_you_feel_unsafe_when_limbs_are/ | {
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"I’m not a psychologist but I imagine it has to do with feeling exposed. When you sleep you’re at your most vulnerable so I think the body is trying to protect itself as best as possible before falling asleep. It’s that or because my parents let me watch Jurassic Park when I was too young and the velociraptors are still out to get me. ",
"So far all the answers are wrong. You don't feel unsafe. What you feel is that something is different. You've forever slept with feet under covers then you try to sleep with them out and it interrupts your sleep. It's the same if for a long time you haven't been chewed on by a velociraptor and now you're being chewed on. Can't tell if its bad or not but better run just in case.\n\nTo see how this works try sleeping with kitchen gloves on. You'll have trouble sleeping for 3 days then it will seem normal and you'll sleep just fine.\n\nTo see how this works add a new sleep partner that tosses and turns. It's sleepless misery for the first 3 nights then it seems normal.\n\nTo see how this works stick your feet out on a hot night. You'll have trouble sleeping for the first 3 nights. Then you'll sleep no different feet in or out.\n"
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3jnnqx | why is there so many muslims in indonesia, malaysia ... ? | Edit : My question may seems a bit racist for some of you but I am not. I thought it would have been more logical for these countries to be animist or buddhist. I don't have any problem with muslims and people from there ! I just wanted to understand why that's it. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3jnnqx/eli5why_is_there_so_many_muslims_in_indonesia/ | {
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"Back in the day the Indian Ocean was host to a lot of trade (for the time). Monsoon winds helped reliably carry trade from as far as China to East Africa. \n\nA lot of the trade came to be dominated by Muslim merchants. In much the same way that West African kings and merchants began converting to Islam to share a religious ties with their Arab trade partners, some rulers and wealthy traders in what is, today, Indonesia and Malaysia (and Brunei and some other places) converted to Islam. \n\nIslam grew slowly in the region over centuries, but it was always primarily due to trade links to Islamic polities on the Indian subcontinent and Arabia."
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bglqtz | why are some gun calibers stronger than others, yet going by name 7.62mm is weaker than .338? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bglqtz/eli5_why_are_some_gun_calibers_stronger_than/ | {
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"The caliber refers to the size of the projectile, not the amount of powder used to propel that projectile.",
"Different calibers use different amounts of powder and different weights of bullets. 7.62 is a metric measurement that equals .308 in inches compared to .338.",
"The naming of ammunition doesn't give you all the relevant information about a round. Most of them are simply named based on the caliber - the diameter of the bullet. That doesn't tell you anything about the length/mass of the bullet or how big the powder load is.\n\nUltimately, if you want to understand these things, you just need to look them up & memorize them - there's no real logic behind a .22LR being a child's plinking round while a .223 Remington is the round of choice for the US military.",
"You've only listed diameter. That's about as helpful as listing the length of a car and trying to estimate its speed. You've basically said \"I've got a 3 meter long open wheel car and a 3.4 meter long open wheel car, why does the 3.4 meter long one go faster?\" You've missed that one is a GoKart powered by a lawnmower engine and the other is an Ariel Atom with a V8 engine in the back.\n\nYou need three dimensions of a cartridge(bullet+case/powder) to estimate its power. The diameter of the round is one of them, but without knowing how long the case is and how large of a diameter the case is you have no idea how much gunpowder is involved. Even between 7.62mm rounds, there is a huge difference between the 7.62x39mm round used by AKs and the 7.62x51mm round used by NATO sniper rifles and the 0.300 Lapua Magnum.\n\nThe 7.62x39mm is the shortest round of the bunch and therefore the weakest, the 7.62x51mm has significantly more gunpowder behind it thanks to its much longer case, but the .300 Lapua Magnum has an even longer 69mm case that is 25% wider.\n\nYou really care about the volume of gunpowder vs the mass of the bullet, not even the diameter of the bullet."
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2s8bjt | how does using cough medicine help your health? | I always thought cough medicine would be worse for you in the long run, since it stops you coughing up stuff that shouldn't be where it is. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2s8bjt/eli5how_does_using_cough_medicine_help_your_health/ | {
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"text": [
"It doesn't help your health, it simply suppresses your cough. IOW: It alleviates a symptom; it doesn't cure an infliction. "
]
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|
5y7lh8 | what happens to dead bodies without any family or friends? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5y7lh8/eli5_what_happens_to_dead_bodies_without_any/ | {
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"Depends on the state but if there is no will or estate left behind then they will usually be cremated. In my area if organ donors are found this way they sometimes make it to our forensic labs to help with decomp analysis or experimental use for high profile cases ",
"Many counties have paupers cemeteries where they would bury unclaimed deceased. Now a days dye to cost, many bodies are cremated, and if their ID, etc is known the box of ashes will be stored for a bit trying to notify next if kin. "
]
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65prfd | how did nail polish become a thing? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/65prfd/eli5_how_did_nail_polish_become_a_thing/ | {
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"In Ancient Egypt and a few other ancient cultures the wealthy lacquered or otherwise painted their nails as a sign of status. The fact that they were able to afford the make-up and lived a leisurely enough life that they did not have to use their hands for labor thus breaking/damaging them was a major thing for the wealthy. That carried on through various cultures up until modernity where make-up became cheap and most people's jobs stopped being physical. ",
"So this is kind of bizzare- When women ovulate (so when they are fertile) they sometimes can have a slightly flushed skin tone. Some people realized it was attractive for a woman to add blush to her cheeks, and red coloring to her lips and nails. The subconscious reason it's attractive is because it's a sign of fertility. "
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2z52yz | why do humans seem to be the only animal that actively helps and feeds other strange* animals? | How many times do you see people helping a baby after it hurts itself. Or how many people feed wild animals.
How come you never see (I guess my question is DO they) a wild animal help another wild animal? Like, I've heard stories of wild lions and snakes taking care of a human baby. (Okay, not take care of but protect). What is going through these animals heads?
Do wild animals actively help other wild animals that are injured? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2z52yz/eli5_why_do_humans_seem_to_be_the_only_animal/ | {
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"There are cases, noy entirely sure why(instinct?) but there are cases.\nFor instance when X female mammal breastfeeds some other X mammal.",
"Many animals have a protective/parenting instinct. Dolphins are known to protect humans from sharks"
]
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|
1zosjs | if there was a nuclear strike, why wouldn't be able to make the missiles explode at a safer distance with a drone or a different missile? | I know that we can use missiles to shoot down other falling objects, so why couldn't we scramble a missile or drone to intercept and explode one before it reached its destination? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1zosjs/eli5if_there_was_a_nuclear_strike_why_wouldnt_be/ | {
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"text": [
"ICBM's are extremely fast (upwards of Mach 23 on the LGM-30 Minuteman) towards the re-entry phase of the missile as it returns into earth's atmosphere. \n\nThe best odds would be to strike one before it re-enters earths atmosphere which would involve creating military bases to track enemy projectiles and send out missiles to intercept them - which means they have to be built close to the hostile country to be effective."
]
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96n2qp | why do so many game devs tie physics and other calculations to frame rate? | So many games ported to PC have horrendous support for higher refresh rates, which I know is because the developers have tied certain things like physics calculations to the frame rate. Is this done for a good reason today, or is this a relic of the bronze age of gaming that should and will get better? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/96n2qp/eli5_why_do_so_many_game_devs_tie_physics_and/ | {
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"text": [
"Because it's easier. There are two other options:\n\n1) make physics and logic still tied to the actual framerate but scale it by the time between each frame\n\n2) run physics seperately at a fixed rate and interpolate data when you render. So the FPS may be, say, 100, but physics calculations is still running 30 or 60 times a second.\n\n---\n\n1) has issues, notably that if you have very high framerates then you'll get into stability issues with 32 bit floating point numbers. It's also not deterministic (testing issues) and for games with replay systems, well, no luck here.\n\n2) is the most \"complete\" option, but it's also very complicated to implement.\n\nTo tie physics and kinematics into frame rate is a simple solution that does the job. For consoles where you'll only target one framerate, it's a practical solution. \n\nThese days, as third party engine use is more common it's not as much an issue, since the hard engineering work is already done by Unity or Epic.",
"Because it's quick and easy.\n\nWhen making a game you need to decide how often it's going to refresh. Since the player will only ever see the difference between two frames (if an update occurs between two updates corresponding to different frames, that specific refresh will never be seen by the player) it makes sense to link the refresh rate of the engine with the framerate - why waste resources on stuff the player won't even see? \n\nOf course, this does make sense on the specific condition that the framerate is constant. And a lot of players don't want to be tied to a specific framerate. ",
"It's the easiest way to get consistent physics on a platform where you expect a constant framerate. Game consoles are the most common example since they all have the exact same hardware.\n\nVariable frame rate means you either have to decouple the physics from the graphic frame update or write the physics engine to 'step forward' in time in variable-length time steps. Neither option are easy and it's very common to have strange bugs like falling through floors because of weird corner cases in collisions.",
"You're kind of misunderstanding the issue.\nDevs don't do it on purpose necessarily to mess with gamers, but it's something that can be remedied with properly planned programming.\n\nSo let me explain it as simply as I can without too much game dev garble.\n\nWhen programming anything, the speed of the program is automatically tied to the power of the hardware it's running on. Programmers can make their programs run on any platform at the same frame rate using an added calculation. (Time.DeltaTime in the Unity3D engine)\n\nGames for consoles only are usually programmed directly for the consoles specifications, and therefore programmers neglect to plan ahead with these added calculations.\n\nSo if a programmer doesn't plan ahead, a PC port can prove to be glitchy, because PC gamers usually run hardware much higher than current consoles.\n\nHope it clarifies a bit.\n\nEdit: This answer is 100% correct. Downvoting it won't make it any less right. Source? I'm a game developer, with a degree in game design. I've programmed and scripted for years. "
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a2tu83 | what happens in the us when a president dies? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a2tu83/eli5_what_happens_in_the_us_when_a_president_dies/ | {
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"You haven't been paying attention. When Gerald Ford died they closed the stock market on January 2, 2007. When Reagan died the markets were closed on June 11, 2004. Not a new thing. It's a national day of mourning so the markets are closed and flags will be half mast. They have been doing this since William McKinley died in 1901. ",
"The same happened when Reagan died a few years ago. Federal services, banks, and the stock market shut down on the funeral day. The funeral is televised, including the processional parade. Flags are also flown at half staff from the announcement of the death until the day after the funeral. ",
"Well here the president declared a national day of mourning and practically that means that Federal Workers get the day off. Since some companies follow along with what the government does in terms of closures that does have a ripple effect and so Wednesday will be a de facto holiday. But a somber holiday, not a \"woohoo!\" holiday. \n\nThe \"stock market\" (there are a lot but principally the NYSE) doesn't have to close but apparently there is a tradition of doing so. ",
"ELI5 is not for current events. Questions like this are better in r/outoftheloop or r/askanamerican."
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Subsets and Splits