q_id
stringlengths 5
6
| title
stringlengths 3
296
| selftext
stringlengths 0
34k
| document
stringclasses 1
value | subreddit
stringclasses 1
value | url
stringlengths 4
110
| answers
dict | title_urls
sequence | selftext_urls
sequence | answers_urls
sequence |
|---|---|---|---|---|---|---|---|---|---|
13wcq3 | differences between hong kong and china. economic, political, cultural, etc.. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/13wcq3/differences_between_hong_kong_and_china_economic/ | {
"a_id": [
"c77r1ud"
],
"score": [
2
],
"text": [
"Hong Kong was ruled by the British for over 150 years, up until 1997. Because of that they have western style capitalism with free trade and little government control. "
]
} | [] | [] | [
[]
] |
||
7ghtus | how does static cling work? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7ghtus/eli5_how_does_static_cling_work/ | {
"a_id": [
"dqj754o",
"dqjh7bg"
],
"score": [
2,
2
],
"text": [
"That is an honest to god mystery of the universe. Electrons get rubbed off on a surface through friction. This gives it a charge. This charge then electrostatically attracts other charges, causing ‘cling’. The how isn’t the mystery.\n\nThe mystery is why it can beat gravity (pull stuff up, or stick stuff on ceilings and stuff). And that is a very active physics problem.",
"Some materials do to their chemical structure have a stronger hold on electrons and we call this electronegativity. \n\nRubber has a greater electronegativity than your hair. So when you run a balloon on your hair it steals electrons.\n\nIn solid you have positively the positively charged nucleous of an atoms which doesn't move and the negatively charged electrons which can move around sometimes hoping from atom to atom think electricity.\n\nNow you take that negative balloon and place it on a wall this pushes back the electrons on the wall and creates an area of the wall that's positively charged this is attracted to the negative ballon. The attraction the ballon experiences from the positive part of the wall is greater than the repulsion it experience from the pushed away electrons because the electrons are farther. The electrostatic force is inversely squared proportional which just means if you double the distance you get 1/4th of the force; if you times the distance by 5 you get 1/25th the force and so on.\n\n The strength of of the electrostatic force is way stronger than the force of gravity but it can neutralize itself if you have an equal number of protons and electrons evenly spread out they cancel eachother out, and because the electrostatic force is so strong they usually do. But a little imbalance can cause a noticeable force. Where with gravity all masses always attract even if it is relatively weak the effect can stack because it is never \"neutralized\".\n\nTl;dr\nLikes repel opposites attract.\nSomethings like balloons are good at stealing electrons and get negative. When it goes to a wall it pushes the electrons away and makes a positive spot to stick to."
]
} | [] | [] | [
[],
[]
] |
||
5bdiar | why are sportspeople more likely to get injured now compared to decades ago? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5bdiar/eli5_why_are_sportspeople_more_likely_to_get/ | {
"a_id": [
"d9nmqw3",
"d9nmt4n",
"d9no5g0"
],
"score": [
6,
7,
2
],
"text": [
"It's not that they're more likely. It's more likely that we can diagnose/recognize injuries. ",
"Higher speeds and more wear and tear are the two major reasons. Think of this for a young pitcher. Back in the day he'd pitch a couple months during high school and then either go to the minors or college. Now kids have their high school teams and travel teams that play year round. So they're burning through their arms 4 times faster before the games actually mean anything.",
"Several factors:\n\n1. In the NFL (and other levels of football) guys would play with non-obvious injuries. Concussions in particular, but also strained muscles and lots of things that can only be diagnosed with MRI.\n\n2. In baseball, pitchers throw harder than ever. The Cubs' Aroldis Chapman throws around 2/3 of his pitches at over 100 mph, and there are numerous pitchers who will hit 100mph every night. In 1980 a pitcher hitting 100 mph once would have been the headline of the night. This extra speed means the pitcher's arm is that much more taxed with every throw.\n\n3. In some leagues (MLB and NBA in particular), players are guaranteed lots of money. If they suffer a career-ending injury, the team still has to pay them, so there's an incentive to push players less hard if it means keeping them in the game."
]
} | [] | [] | [
[],
[],
[]
] |
||
4owm5g | how does pickling work | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4owm5g/eli5_how_does_pickling_work/ | {
"a_id": [
"d4g91s4"
],
"score": [
3
],
"text": [
"I believe because the vinegar makes the water solution too acidic for most bacteria to survive in. "
]
} | [] | [] | [
[]
] |
|
6jes6r | why do bugs seem to fly in circles around one when out hiking, particularly around the head? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6jes6r/eli5_why_do_bugs_seem_to_fly_in_circles_around/ | {
"a_id": [
"djdpy4b"
],
"score": [
41
],
"text": [
"Generally, they are either attracted to the carbon dioxide you are exhaling or the body heat you are giving off. For flies, it's the CO2, mosquitoes seek body heat. And the head is usually the hottest part of your body, and it's usually exposed, especially in the type of weather that mosquitoes are an issue."
]
} | [] | [] | [
[]
] |
||
6wuz2e | why does getting something wet (like fabric) make it easier to squish into a smaller size? | It also happens with a lot of other dry things, like bread. Getting things wet often makes it easier to squish them down into a smaller size. This seems counter-intuitive to me as the presence of water indicates the presence of more *stuff*, and therefore the need for more space. Thanks. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6wuz2e/eli5_why_does_getting_something_wet_like_fabric/ | {
"a_id": [
"dmaykq7",
"dmbea4t"
],
"score": [
6,
3
],
"text": [
"Generally speaking, it makes the thing stick to itself.\n\nBread or fabric generally has a pattern to it, with holes that are held in place.\n\nThe water makes it so that the forces pushing the holes open are weaker than the forces holding them shut (once you have pushed them shut) via surface tension.\n\nIt may also (as is the case with bread) actually begin to break down the structural membranes, or at least render them soft. \n\nThe excess water is expelled when you squeez",
"I've built roads and highways. Water is absolutely needed to compact soils and gravels to get a density needed to hold traffic for years. You can't compact any material dry because it's full of air and you can't squeeze it out. So you flood the material with water which will replace the air and you CAN squeeze the water out. Then the particles stay compacted because air can't get back in so the vacuum holds the materials together. I have no clue if this hold true for fabrics but I'd wager a bit it's similar. "
]
} | [] | [] | [
[],
[]
] |
|
a2ifnd | why doees my navel fill up with lint every day, and why is it always dark blue? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a2ifnd/eli5_why_doees_my_navel_fill_up_with_lint_every/ | {
"a_id": [
"eaymv0l",
"eayx99z",
"eaz0gf8"
],
"score": [
10,
2,
2
],
"text": [
"What color shirt do you wear? Or are your pants high waisted and jeans/blue?",
"Maybe things you sit on (couch, pillows). Blankets. Pieces of clothing you wear. Or dust particles in the air or sticking to objects you touch. (Dust may have fibers in it.)\n\nSome days I have belly lint and some days I don’t. Usually when I do, it is because I wore my fuzzy hoody or I was rolling around on the carpet.",
"What color are your towels? "
]
} | [] | [] | [
[],
[],
[]
] |
|
1opn4b | if a doctor (hypothetically) were to transplant my testicles on to another man's genitals (still functioning) would those testicles continue to produce my sperm or begin to produce his? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1opn4b/eli5_if_a_doctor_hypothetically_were_to/ | {
"a_id": [
"ccuabao",
"ccuabr7",
"ccucp22",
"ccujftq"
],
"score": [
8,
136,
9,
4
],
"text": [
"No, they would never become his. They would always be yours. The cells that make up the testicles still contain your DNA.",
"They would hypothetically produce your sperm, but his immune system would attack the testes and the sperm they produce.",
"His. \n\nSperm originates from his sperm stem cells. The haploid DNA will be his as well as the proteins used to form the sperm structure.\n\nA real-life analogy would be an allogenic bone marrow transplant. A patients original bone marrow would be destroyed and replaced witg the donor's. All cell lines produced afterwards would essentially be identical to the donor's. \n",
"/r/askscience ... and then tell me what they say. Please."
]
} | [] | [] | [
[],
[],
[],
[]
] |
||
e7s3s8 | why do cinemas use projectors on a huge wall instead of a huge screen? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/e7s3s8/eli5_why_do_cinemas_use_projectors_on_a_huge_wall/ | {
"a_id": [
"fa40r2j",
"fa40xkk",
"fa46t3w",
"fa48j80",
"fa4cobs"
],
"score": [
2,
23,
3,
3,
2
],
"text": [
"It's cheaper to paint a wall white. Screens are expensive.",
"To make a huge image, it's much cheaper to get a powerful projector than to build a high-resolution video screen that big.",
"Price of a screen goes up exponencially the bigger it is. Its WAY cheaper to buy projector than a big ass screen.",
"Besides cost, a projector has a scalable size, so a theater with multiple cineplexes can use one type of projector to display different distances and different sizes. \n\nIt would be impossible for a company to produce enough size options for all of the different size theaters out there.",
"Because projectors are at least equal, if not superior, to screens in terms of image quality when you can control the light AND the viewing angle. And they are also much cheaper."
]
} | [] | [] | [
[],
[],
[],
[],
[]
] |
||
b79uyd | why is "imposter syndrome" so prevalent now? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b79uyd/eli5_why_is_imposter_syndrome_so_prevalent_now/ | {
"a_id": [
"ejq6olz",
"ejq8njr"
],
"score": [
3,
5
],
"text": [
"First of all, almost everything is machine made, so most of what we create will never live up what a machine can make. It's become easier to buy something than to make something so we've lost our drive to create, engineer, and build. Secondly, we have created a society where nothing is concrete anymore. Men and women are expected to change, so many people already hide 'who they really are' because they don't want to be chastised. We've made a society of social media where people's entire self worth thrives on internet points. It's this combination of knowing we can't make anything, hiding who we are, but wanting to be amazing for the internet attention that's created imposter syndrome. ",
"There's a lot of reasons, but I suspect social media is one of the main culprits. We are constantly being deluged with the \"best\" parts of other peoples lives (what they want us to see) and assuming that is their average. We know how bad our worst is, and so it brings down what our internal average is. So we think other people are doing better than they are, we are doing worse than we are, and are totally worried other people are going to realize how poorly we are doing.\n\nSo we double down on proving to others how well we are doing, and the more we do that, the more worried we are that they're going to find us out. Meanwhile, we're putting on our best face so the other poor sap sees how well we're doing, knows how poorly they are doing, and can't let anyone else see that, because then we'd realize how poorly they are doing. So they double down on proving..."
]
} | [] | [] | [
[],
[]
] |
||
5vjzsi | why are whole fat dairy products considered healthier than low/no fat products? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5vjzsi/eli5_why_are_whole_fat_dairy_products_considered/ | {
"a_id": [
"de2n61n",
"de2na51"
],
"score": [
3,
2
],
"text": [
"Two reasons. First, eating whole fat dairy is more filling and satisfying than eating no-fat versions, generally leading to fewer overall calories consumed for the rest of the day.\n\nSecond, no-fat dairy is, by consequence, a high-carbohydrate food filled with easily-digestible sugar. This makes it unbalanced and likely to lead to faster and higher insulin spikes in your blood...a generally unhealthy thing.",
"Mostly because in order to keep the low fat version tasting good, the fat is replaced with sugars, sweeteners and various things to maintain the texture. Overall, this combination can be less healthy than the fat they replaced. Also bear in mind that how healthy something is doesn't just depend on the number of calories it contains."
]
} | [] | [] | [
[],
[]
] |
||
3nahjs | techies of reddit, what is actually happening when my phone/laptop freezes but music continues playing in the background? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3nahjs/eli5_techies_of_reddit_what_is_actually_happening/ | {
"a_id": [
"cvmb2wr",
"cvmbjll"
],
"score": [
4,
2
],
"text": [
"The processes for the visual, be it the interface, or video, is glitching crashed, or many other things, while the process for audio is still going.",
"I'm guessing your display drivers (software that makes your display work) broke. There are plenty of other jobs your computer does in parallel and so music continues playing."
]
} | [] | [] | [
[],
[]
] |
||
5xc9rr | how would the gravity and environment of mars affect the people that colonized it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5xc9rr/eli5_how_would_the_gravity_and_environment_of/ | {
"a_id": [
"degxbux",
"degzcmo"
],
"score": [
3,
3
],
"text": [
"There is almost no atmosphere on Mars (1% of Earth's Sea Level pressure). This means Humans who colonize Mars will either be indoors or in a pressure suit all the time. That's a key feature in the design of their air-tight structures and vehicles.",
"This is a complex topic with many possibilities, and much uncertainty, but I'll do my best to ELI5. \n\n\nWe can separate the effects on 2 levels: **Physical** and **Psychological.**\n\nOn a **psychological** level, its hard to predict how it would affect the first colonizers. The feeling of belonging to a new place wouldn't be there right away, but with generations to come, it would eventually settle. \n\n\nThose 2nd generation Martians would be introduced to the science fields and exploration much sooner than your average Earthling. They could also develop a feeling of entrapment, due to not being able to experience the same things as people on Earth.\n\n\nWith enough time elapsed, routines would be created which would eventually give birth to a new set of habits, maybe even a culture.\n\n\nOn a **Physical** level: Mars gravity being 38 % of Earth's brings some problems like muscular/bone atrophy, eyesight problems, sleep disturbance. But since the first colonizers, would not experience the **raw** environment and gravity of Mars, it wouldn't be much different from the astronauts who now live on the ISS. \n\n\nIf there was a 2nd generation born on Mars, those people could experience differences in body morphism, like being taller and having leaner body parts. Also they would probably not be able to come to planet Earth without hurting how their body works, much less being able to move/walk.\n\n"
]
} | [] | [] | [
[],
[]
] |
||
3ap8w9 | why if i multiply any random number with 9 the sum of that number is always 9? | Examples:
1x9=9
2x9=18=1+8=9
5x9=45=4+5=9
25x9=225=2+2+5=9
456123789x9=4105114101=4+1+0+5+1+1+4+1+0+1=27=2+7=9
Please explain why the number 9 does this. And for example the number 7 doesn't?
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3ap8w9/eli5_why_if_i_multiply_any_random_number_with_9/ | {
"a_id": [
"csenzcz",
"cseof3p",
"csepvog",
"csesixs",
"csf15pb",
"csf6c60"
],
"score": [
66,
77,
2,
4,
2,
2
],
"text": [
"Suppose your number is\n > N = a + 10b + 100c + 1000d\n\nI can change 10 to 9+1, 100 to 99+1 and 1000 to 999+1, giving\n > N = a + (b + 9b) + (c + 99c) + (d + 999d)\n\nNow rearrange the order of terms to get\n > N = (a + b + c + d) + (9b + 99c + 999d) \n > N = (a + b + c + d) + 9(b + 11c + 111d)\n\nNow N is divisible by 9, and 9(b + 11c + 111d) is divisible by 9, so (a+b+c+d) must also be divisible by 9. So the sum of the digits of any multiple of 9 is also a multiple of 9.\n\nKeep summing the digits of each result and you'll keep getting smaller multiples of 9 until you only have one digit and can't sum the digits any more. But the only non-zero one-digit multiple of 9 is 9 itself, so 9 must be the answer you end up with.",
"Whatever integer is the base of your number system, the one before it will have this property in that number system. In other words, the largest digit of the number system has this property - in base ten that is 9. \n\nFor instance, in base eight: \n1* 7 = 7 \n2 * 7 = 16 → 1 + 6 = 7 \n5 * 7 = 43 → 4 + 3 = 7 \n25*7 = 223 → 2 +2 + 3 = 7 \n4561237 * 7 = 41031131 → 4 + 1 + 3 + 1 +1 + 3 + 1 = 16 → 1 + 6 = 7",
"9 = 10-1\n\n9*1 = 9\n\n9*2 = (10-1) * 2 = 2 * 10 - 2 * 1 = 1 * 10 + (10-2). The ones and tens digit sum to 1+10-2 = 9.\n\n9 * 3 = (10-1) * 3 = 3 * 10 - 3 * 1 = 2 * 10 + (10-3). Sum to 2+10-3 = 9.\n\netc.\nThis factorization works due to the nature of 10 as our base unit. In any base b, you will find this with b-1.\n\nFor multiplication by numbers with more than 2 digits, the trick makes the sum of their digits equal to 9 * (#digits-1). Ex 11 - > 99 - > 18 = 9 * 2.\n\nThe trick technically only works for single digit numbers (excluding 0, and including 10); they will sum to 18 for two digit numbers (excluding 10, and including 100), etc. The rule is slightly messed up by numbers with 0s in them, but oh well. Due to this sum again being a multiple of nine, the same exact factorization can be applied again to work its way down to 9.\n\nAgain, this is all due to 9 being exactly 1 less than our base 10.",
"This is a common example of [modular arithmetic](_URL_0_).\n\nOther respondents have explained why it works for 9. To add to their responses, it also works with 3 for the exact same reason (10 is 1 mod 3; 100 is 1 mod 3; etc.).\n\nAlso, it works with 11 in an odd way.\n\nIf you add the odd digits and subtract the even digits, numbers whose sum is divisible by 11 are themselves divisible by 11.\n\nExample:\n\n > 418 [11*38]\n\n > 4 - 1 + 8 = 11\n\nThis is because 10 is -1 mod 11, but 100 is 1 mod 11.\n\nYou can prove this pretty easily since 9x11=99, 909x11=9999, etc.",
"It is because of the divisibility rule of 9. \n\nIf you take any number which is divisible by 9 and add its digits, the sum will be divisible by 9. Now since this sum is divisible by 9, then the sum of its digits must be divisible by 9 too. You keep on adding and adding until you reach a sum that is only 1 digit. This must be divisible by 9. However there is only one single digit number that is divisible by 9, and its 9 itself.\n\nThis is why you always reach 9.\n\nThe divisibility rule is very similar to that of 3's. If you add the digits of a number divisible by 3, the sum will be divisible by 3. If you keep on adding until you get a single digit, that single digit will also be divisible by 3. Except in this case, there are 3 possibilities. They are 3, 6 and 9.\n\nObviously the follow-up question is how this divisibility rule came up. For this you need to be aware of 2 things. The first one is how the digits of a number can be expressed algebraically. Let's consider 456. You cannot say \n > 456 = xyz, where the digits are x=4, y=5 and z=6. \n\nBecause xyz = x × y × z = 4 × 5× 6 =120.\n\nInstead, you express it like this:\n > 100x + 10y + z, so for x=4, y=5 and z=6, we get 400+50+6 = 456.\n\nThe second thing is, consider two numbers, a and b. If both of them are divisible by another number n, then (a+b) will also be divisible by n.\n\nOK, showtime.\n\nA 2 digit number can be expressed as (10x + y).\n > 10x + y = 9x + (x + y)\n\n(x + y) is the sum of the digits. 9x is divisible by both 3 and 9. Now, if (x + y), i.e., the sum of the digits are divisible by 3, then the 2 digit number 10x + y = 9x + (x + y) will be divisible by 3 [the a and b divisible by n rule, here a = 9x and b = (x + y), n is 3 or 9]. Similarly, if the sum of digits is divisible by 9, then 10x + y will also be divisible by 9.\n\nIn case of 3 digit numbers, they can be expressed as (100x +10y + z).\n > 100x +10y + z = 99x + 9y + (x + y + z)\n\nHere (x + y + z) is the sum of the digits, 99x and 9y are divisible by 3 and 9. You can increase the number of digits, but this pattern will continue.",
"Magic.\nA special type of magic using a special set of rules.\nIf you look at 1, or 10, those are different numbers, but if you add the digits, you get 1 = 1, or 1+0 = 1, the same thing. You are taking the 1 in the tens place, and using magic to turn it into a 1 in the ones place. If you have 23, then we get 2+3 = 5, we are taking the 2 in the twenties place, and turning it into a 2 in the ones place, while the 3 gets left alone.\n\nTurning a 10 into a 1 is the same as subtracting by 9. Turning a 50 into a 5 is the same as subtracting by 9 five times, or 45.\nSimilarly, taking a 100 and turning it into a 1 is the same as subtracting by 99. Taking a 4000 and turning it into a 4 is the same as subtracting by 999 four times.\n\nThus, \"adding the digits\" and ignoring their original location is the same as subtracting some number of 9s and 99s, and 999s etc, all of which are multiples of 9. Thus, if you take a number which is a multiple of 9, and subtract another multiple of 9, you get a smaller multiple of 9, until eventually you reach 9 and stop."
]
} | [] | [] | [
[],
[],
[],
[
"https://en.wikipedia.org/wiki/Modular_arithmetic"
],
[],
[]
] |
|
4ynmpf | why are energy and mass similar? | I have heard this fact before, but I do not understand what it means and how it can be applied. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4ynmpf/eli5_why_are_energy_and_mass_similar/ | {
"a_id": [
"d6p7a3r"
],
"score": [
3
],
"text": [
"All mass is energy, but not all energy is mass. This is a result of Einstein's special theory of relativity."
]
} | [] | [] | [
[]
] |
|
326t8o | where did blacksmiths go after industrialization? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/326t8o/eli5where_did_blacksmiths_go_after/ | {
"a_id": [
"cq8flls",
"cq8g5rk",
"cq8hxve"
],
"score": [
2,
4,
2
],
"text": [
"Someone has to tell people how to run those machines that took their jobs...",
"Other jobs. A skilled blacksmith is probably a very valuable worker in many other professions. Since blacksmiths would have a very advanced knowledge of metals and toolmaking, factories would probably be very interested in hiring them.\n\nAnother point is that jobs don't die immediately. When industrial machines are invented that can produce things more efficiently, the reality is that most regions don't have immediate access to those new machines. It would take many years for mass-produced items to completely take over for handmade goods.\nThe Industrial Revolution happened between 1760 and 1820 (or 1840). 60-80 years is longer than any one person would be working, so many blacksmiths during that era would have most likely lived their entire lives as smiths, and done good business throughout.",
"There are still blacksmiths making artisan products, and they sometimes make a fair bit of money. Granted, this isn't very common."
]
} | [] | [] | [
[],
[],
[]
] |
||
1qrist | what causes that feeling in your chest when you're really horny? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1qrist/eli5what_causes_that_feeling_in_your_chest_when/ | {
"a_id": [
"cdfqybj"
],
"score": [
8
],
"text": [
"I'm going to take a stab at this one, someone will correct me if I'm wrong.\n\nAs far as I have always known, when we become aroused we go through a stage of vasocongestion which is in layman's terms, a sex flush, or rather an increased blood flow. Apparently this affects women more than men with almost 50% increasing chance of this happening to women.\n\nDuring the sex flush, light pinkish spots could develop under the breasts and spread to other parts of your body such as your face, arms, chest, etc. It also darkens the clitoris and the walls of the vagina. For males, the flush could start near the upper abdomen and then spreads to your chest, face and the rest of your body.\n\nOther changes include an increase in heart rate as well as in blood pressure, feeling hot and flushed and perhaps experiencing tremors."
]
} | [] | [] | [
[]
] |
||
1w6h2m | server wages in the u.s. are they actually making minimum wage? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1w6h2m/server_wages_in_the_us_are_they_actually_making/ | {
"a_id": [
"cez4mjr",
"cez4mpk",
"cez4n1b"
],
"score": [
2,
3,
2
],
"text": [
"Depends on the state. In some states they are allowed to make less than minimum, in other states they must make minimum or more. Depends on the restaurant as well. Some restaurants (such as fine dining) obviously pay their servers better than minimum wage.",
"Yes, an employer is required to compensate them up to minimum wage if they don't get it in tips.\n\nIf you're a server and work decent hours and can't earn minimum wage in tips, you're probably a terrible server.",
"Servers that do not get minimum wage through tips must be compensated up to that point by their employer."
]
} | [] | [] | [
[],
[],
[]
] |
||
5g02e6 | why can my phone accurately recognize spoken language in a crowded hallway but captchas are still used to prove you're human? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5g02e6/eli5why_can_my_phone_accurately_recognize_spoken/ | {
"a_id": [
"daode15",
"daodil5"
],
"score": [
2,
5
],
"text": [
"It reminds me of this _URL_1_ comic where what you think may be simple is much more complicated to a computer. \n\nCaptchas are surprisingly difficult for computers because their recognition for shapes is not amazing especially when other shapes are intersecting with them. \n\nRecognizing voices and language is just looking for patterns and weighing it versus similar patterns, but very quickly. If another voice enters it's easy to remove it, but in a captcha it's hard to tell what the voices are. \n\nAlso know, [those are not perfect, they make mistakes all the time and have trouble with many different accents](_URL_0_). And if you don't speak with that specific cadence, even a basic US west coast accent can have some bad quirks. ",
"There's a secret trick, *your phone* doesn't accurately recognize spoken language in a crowded hallway. The audio is uploaded to Google's huge cluster of computers dedicated to the cause. \n\nIt actually takes a lot of processing power to do voice."
]
} | [] | [] | [
[
"https://www.youtube.com/watch?v=SGxKhUuZ0Rc",
"http://xkcd.com/1425/"
],
[]
] |
||
c8d6oe | why do wine bottles usually use corks instead of lids or caps? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/c8d6oe/eli5_why_do_wine_bottles_usually_use_corks/ | {
"a_id": [
"esm1fa9",
"esm471z",
"esmg4uj",
"esml4er"
],
"score": [
27,
2,
4,
2
],
"text": [
"Yes, it is to do with the fermentation process and allowing oxygen to enter the bottle as it ages. \n\n\nFermentation is what we call it when the yeast (living organisms) change the grape juice by eating the sugar and creating the alcohol and flavors of the finished wine. \n\n\n \n\n*Many wines develop undesirable aromas under anaerobic –no oxygen– conditions; a small amount of oxygen will eliminate those trace* [*thiol compounds*](_URL_2_) *responsible for the aroma of rotten eggs* [*or burnt rubber*](_URL_0_)*. Oxidation products also react with the* [*red anthocyanin molecules*](_URL_3_) *from the grapes to create stable pigments in red wine.*\n\n*The way a bottle is sealed will directly affect how much* [*oxygen passes into the wine*](_URL_1_) *each year. That will directly affect the aging trajectory and determine when that wine will be at its “best.”*\n\n[*_URL_4_](_URL_5_)",
"At least for South African wine, screwtops are pretty common, except for some labels, and usually at a (sometimes considerably) higher price point.",
"It's all marketing. Our preconceived notion of a \"good\" bottle of wine is a bottle with a cork, and a screw cap doesnt fit that notion. I know that in the US markets some wines are sold with cork bottles, while in other parts of the world that very same wine is sold with a screw cap. Ultimately it makes no difference",
"Tradition. It used to be the most efficient and cheap way to seal the bottle in some wine growing regions."
]
} | [] | [] | [
[
"https://winefolly.com/tutorial/33-bizarre-wine-flavors/",
"https://winefolly.com/tutorial/the-truth-about-oxygen-and-wine-aging/",
"https://winefolly.com/review/where-wine-flavors-come-from/",
"https://winefolly.com/update/young-wines-better-than-old-wines/",
"https://winefolly.com/review/chemist-explains-corks-matter-storing-wine/*",
"https://winefolly.com/review/chemist-explains-corks-matter-storing-wine/"
],
[],
[],
[]
] |
||
83ylgy | what factors influence breast size? | Obviously genetics has a big part in it, but what else can influence breast size? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/83ylgy/eli5_what_factors_influence_breast_size/ | {
"a_id": [
"dvljpbx"
],
"score": [
9
],
"text": [
"The biggest determinant is genetics. Aside from that, the person's weight and fat deposits (more fat in the breast area means bigger breasts), and hormones. Hormones would be the 2nd biggest, as estrogen makes breasts enlarge or shrink (many women notice changes in breast size which correlates with their menstrual cycle). "
]
} | [] | [] | [
[]
] |
|
6auxfp | does our vision have a limit? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6auxfp/eli5_does_our_vision_have_a_limit/ | {
"a_id": [
"dhhmntl"
],
"score": [
2
],
"text": [
"Can you see galaxies however many light years away? Sure. \n\nYou don't really see distance. You see the light particles contacting the back of your retina. So if there's light bouncing off of the wall on the opposite side of the hallway and its been in existence long enough for the light to reach your retinas, you'll see the light. If not... you won't. \n\nWhere vision breaks down with distance is the loss of focus and refraction as more light particles bounce and scatter the farther away you are. \n\nSource: I wear glasses."
]
} | [] | [] | [
[]
] |
||
22qz3y | what is a zero-day attack? | Can somebody explain this concept to me? I do not understand it... I read the Wikipedia page and still don't get it. Explain like I'm five | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/22qz3y/eli5_what_is_a_zeroday_attack/ | {
"a_id": [
"cgpismt",
"cgpiudb"
],
"score": [
3,
4
],
"text": [
"the attack is seen in the wild zero days after it is discovered by security researchers. In computer science terminology, this usually means the person who wrote the exploit is also the person who discovered it, and rather than doing the ethical thing and reporting the issue to those people who own some piece of software, that attacker decided to try to profit from their discovery. \n\nA virus attacks some weakness in software. In a Zero-Day attack, the virus is released the same time it is discovered by someone who would care to fix it.",
"Essentially it's a computer attack that happens for unknown reasons.\n\nLook at it this way: say some researcher found a flaw in a program. He notifies the world of this vulnerability. Months go by, then one day some hacker exploits this flaw. This is *not* a zero-day attack. The flaw was known about for months.\n\nA zero-day attack exploits a flaw that was previously unknown. It's called \"zero-day\" because zero days pass between when people found out about the flaw and when it was exploited."
]
} | [] | [] | [
[],
[]
] |
|
4hhl99 | why do bacteria make us sick? why do some bacteria help us? why can't they just chill out in a hosts body and not do anything? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4hhl99/eli5_why_do_bacteria_make_us_sick_why_do_some/ | {
"a_id": [
"d2pnmdx",
"d2pnt23"
],
"score": [
3,
6
],
"text": [
"Put very simply, all a bacteria's actions are necessary for its survival. If you get sick, that means there's some micro-level crap going on inside your body. Most probably bacteria or a virus. And likely, they do that to gain their needs, and possibly to reproduce. Whatever they do, it is a necessity- to survive, and to pass on their genes. Such is the goal of life.",
"Most of them *do* just chill out and coexist peacefully. your skin, inside your nose, all along your intestines, you have more bacterial cells in and on you than you have *human* cells. One main advantage of these established bacteria populations is they are stable, and stop unwanted or new bacteria from moving in and setting up shop (new ones might harm us)\n\nBacteria in your intestines also help us, by digesting stuff we can't and releasing vitamins like additional forms of vitamin K that can *only* be produced by bacteria.\n\nSome bacteria are not normal to us, like salmonella (harmless to a bird or reptile though), and they can make us quite sick. Others live in soil like Clostridium tetani that produces tetanus toxin, if it gets into a puncture wound it can be fatal (the bacteria can't live in an oxygen environment but it loves dark wet holes, and produces toxin that poison us)\n\nEven different related species, or strains of the same species, can act very different, bacteria can change their genetic code more easily than animals because they reproduce faster and can take in RNA/DNA from other bacteria, picking up new abilities (like sharing antibiotic resistance genes)"
]
} | [] | [] | [
[],
[]
] |
|
3wiifm | why does it matter if barak obama is a muslim? | I hear this argument as a criticism of the US president every now and then, but I don't see how its relevance. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3wiifm/eli5_why_does_it_matter_if_barak_obama_is_a_muslim/ | {
"a_id": [
"cxwfgpf",
"cxwfhg1",
"cxwfq2d",
"cxwfqmb",
"cxwh46q"
],
"score": [
5,
18,
7,
3,
2
],
"text": [
"It's new and untested. All presidents until this point were of Christian denominations and white...Barack Obama changed the game by being black. Having a Muslim sounding name makes people think he's a Muslim, but the fact remains he is not (to my knowledge). If I remember rightly he's not of any particular denomination of any religion, but that doesn't mean he doesn't believe in God.",
"Despite the fact that the US claims to have separation of church and state, religion still plays a factor in politics. Because Christianity is the predominant religion in the US, the people tend to want their leaders to be Christian. Also, the general public thinks all Muslims are terrorists because of extremist groups.",
"Simply put. It doesn't matter. \n\nThe problem is that people in the US seem to think that it does. \"If you aint a christian then you a devil worshiper.\" Seems to be the general consensus among the half educated masses. Especially within the bible belt...",
"There's a whole stack of nitwits who will only vote for Christians as a conscious choice because they want to ensure the US is a Christian country (misguided, obviously). Then there is a pile of jerks who think every Muslim is responsible for the terrorists of 9/11. Add a bunch of fools who would be easily lead by the political opposition into a sort of vague fear of someone different and you've got your majority of voters. Voters. A lot of people don't vote but these people would show up to cast their ballot.",
"Because it matters. One of the main reasons I never considered voting for Romney was because he was a Mormon. Mormons have strict views on certain social issues...and since he never confirmed or denied where he stood in relation to his moral upbringing, I was left to make assumptions. Same with being a Muslim. Sure, there are great Muslims out there. But what sect of the faith do you ascribe to? \n\nJFK was the first catholic president. He had to state that he wouldn't be taking political direction from the Pope.\n\nI think it's reasonable and fair to see what role religion is going to play in someone's political life.\n\nFor me, I want a politician that can hold his job, the constitution's rules separate from his faith. Else we're going to have a Kim Davis president."
]
} | [] | [] | [
[],
[],
[],
[],
[]
] |
|
24io7e | why do some people not experience addiction withdrawal symptoms? | For example, I have smoked for years. I can quit cold turkey and have several times just to prove a point to people. In college, I partied a lot (7 days a week) and also quit all of that cold turkey because I felt like it. I've never met anyone else like this. And oddly enough, addiction problems run in my family. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/24io7e/eli5_why_do_some_people_not_experience_addiction/ | {
"a_id": [
"ch7iqqi"
],
"score": [
3
],
"text": [
"I'd like for you to consider the possibility you are in denial."
]
} | [] | [] | [
[]
] |
|
btfohc | when a human is buried in a coffin, what actually happens with the dead organic matter? | I mean, if one just dies on the ground, the bugs and animals and smaller organisms will consume it. But if it's isolated in a coffin, does it just, mummify? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/btfohc/eli5_when_a_human_is_buried_in_a_coffin_what/ | {
"a_id": [
"eox6sd4"
],
"score": [
27
],
"text": [
"depends how much embalming fluid there is in their veins. generally, after 10 years there's a lot of liquid in there, recognizable skin and bones lots of hair and a dank smell. if the coffin leaks and doesn't flood they get leathery but if it collapses its usually just dirt and bones. i woked at a cemetery. people move and a lot of times they want loved ones exhumed and cremated. the dead travel better as ashes. one time we dug up a teenaged overdose victim from the 70s. her father was retiring to California and wanted her near. she was perfectly preserved and still beautiful."
]
} | [] | [] | [
[]
] |
|
2vfa72 | why is 50 shades of grey rated r and not x? | sorry for the misunderstanding. I understand that they made it R to make more money etc. But I thought the story was mostly about BDSM. So wouldn't this just be a high quality porn movie with a decent plot line? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2vfa72/eli5why_is_50_shades_of_grey_rated_r_and_not_x/ | {
"a_id": [
"coh2rz6",
"coh2tgf",
"coh4dj4"
],
"score": [
9,
4,
2
],
"text": [
"They most likely toned down the sex in order to get an R rating. An X rating is pretty much a death sentence for a film trying to be successful mainstream ",
"Minor note: there's no such thing as X rating anymore. It was replaced in 1990 with the NC-17 rating.",
"Subject matter isn't that important, there have been other movies about BDSM that have gotten R ratings.\n\nWhat is important is the amount of nudity and explicit sexual situations they show."
]
} | [] | [] | [
[],
[],
[]
] |
|
820wem | ; if marijuana “stays in the system” for a week or two, why are humans sober after an hour or two? if it’s in the system, is it technically intoxication for all those days | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/820wem/eli5_if_marijuana_stays_in_the_system_for_a_week/ | {
"a_id": [
"dv6m4eq",
"dv6mfsn",
"dv6n6x0",
"dv6nf7e",
"dv6pxwk"
],
"score": [
8,
26,
7,
5,
6
],
"text": [
"It's not complex. The amount that stays is a very small percentage -- most of it is gone after about 24 hours. The remaining amount is too small to make you intoxicated, but can still be detected with sensitive chemical tests.",
"If I'm recalling my drugs class correctly the effects of marijuana come from it activating the cannabinoid receptors in the brain which are specifically designed to react to marijuana and things like it. Not all of the pot goes directly to these receptors in your brain(the site of action), but ends up hanging out in your fat cells for a while. So if it isn't activating these receptors it really isn't intoxication. ",
"This is how most things work. When you have cold medicine that tells you to take it every 12 hours it's not like at 12.000 hours all the molecules stop working. It has some sort of half life, where the liver and kidneys break it down. If the therapeutic dose is 10 units, you probably have 20 right after you take the pill, then maybe you lose 6% per hour. This gives you 18.8, 17.7, 16.6, 15.6, 14.7, 13.8, 13.0, 12.2, 11.5, 10.8, and finally 10.1. You need to take another pill or there won't be enough to treat your cold.\n\nSame sort of thing with pot, except we have a test that can measure 0.05 units. With that test, it takes 95 hours before there isn't a detectable amount.",
"Getting High is a reaction produced when your brain covers certain receptors with a chemical that it produces in reaction to the THC or CBD in your system. The body then processes the THC and CBD and stores them like anything else that we eat drink or inhale. How long it stores these depends greatly on level of activity, body fat, and metabolism. Someone with a slow metabolism who is overweight and does not exercise often could have traces in a urine test 45+ days after stopping smoking while an Olympic swimmer could probably detox in a 72 hour period. \n\nI would also point out that intoxication does not always mean impairment. Someone who has been drinking energy drinks is considered intoxicated but most would not considered impaired.",
"It’s important to point out that a drugs active form does not remain in your body for the length of a defection period. Marijuana is detectable for an extended period of time because it gets broken down into metabolites, which are not intoxicating, but measurable. "
]
} | [] | [] | [
[],
[],
[],
[],
[]
] |
||
1r5zyt | how do historians or linguists decode and translate an ancient language that hasn't been spoken in a long time? | I just don't even know where one would start. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1r5zyt/eli5how_do_historians_or_linguists_decode_and/ | {
"a_id": [
"cdjxhjo",
"cdjyqgb"
],
"score": [
2,
38
],
"text": [
"This is a really interesting question.\n\nI mean, I know some languages were decoded with Rosetta Stone equivalents. But what about extremely ancient languages like those spoken in Uruk? And, do we know how do they could be pronounced? How? ",
"I suppose it depends on what the circumstances are. In cases like Ancient Egyptian hieroglyphs, there wasn't anything that could be done until we got our hands on the Rosetta Stone. \n\nBasically, we have two options depending on how ancient it is and if there is text surviving from it. \n\nIf we have some sorts of texts from the language, they are compared to languages that are children of that ancient language. We can see residual words, phrases, sounds, and grammar from the children that can be compared to the parent language. We can then piece together different translatable portions so we can use context to determine other portions. It's certainly a very difficult task, and it's near impossible to make a full reconstruction without something like the Rosetta Stone in which a language still in modern use (sort of) is directly translating the unknown language.\n\nThe more challenging alternative is reconstructing an ancient language with no existing language data. In this case, the only thing that can be done is reconstruct a theoretical proto-language since there is nothing existing that can prove anything. It involves painstaking analysis of data on words, sounds, and grammar of languages born from that hypothetical language. \n\nIt becomes a game of \"what words seem to look similar in most of these languages? how can we reconstruct a proto-form from the similarities in those similar words (fake example: wodar, wuter, woter= possibly woter?)? how can we explain places where not all languages share a similar pattern/word for something?\"\n\nProto-language construction is seriously a headache, and requires a lifetime dedication to something that can't be proven and may never truly be complete. \n\nRe-construction translation is also quite challenging, but fruitful and enriches our understanding of history in a big way. It's very similar to cryptology, since it's about decoding a system of coding (turning ideas/words in your head into words out loud/on paper) through puzzle-solving and looking at related codes to draw out similarities (which is why Navajo was such an uncrackable code during WWII...they couldn't draw on past codes' characteristics since it was built on nothing we were used to in codes OR in language grammar in real languages)\n\nTL;DR: Very patiently, with luck and a very problem-solving oriented mind. Also, wall of text. Apologies."
]
} | [] | [] | [
[],
[]
] |
|
1g16wa | nuclear anti-aircraft weapons | Did they have any (theoretical) practical use or were they just to show off? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1g16wa/eli5_nuclear_antiaircraft_weapons/ | {
"a_id": [
"caftsjx",
"cafv0ol",
"cafvqjb"
],
"score": [
2,
2,
2
],
"text": [
"In a time when guidance systems weren't terribly advanced, being able to aim in the general vicinity of a swarm of aircraft was a great advantage. And having a nuke go off over your country was preferable to letting those planes drop several nukes directly on your cities or airbases.",
"They were meant to attack bombers that were themselves carrying nukes. Their heyday was before ICBMs became a thing.\n\nThey were very small nukes and they'd be exploding very high, so they wouldn't have had huge effects on people still on the ground, assuming everything went right. In any case, their effects for those on the ground would be presumably less than the effects of the actual nukes the bombers were trying to drop.",
"During the 1950's and 60's the USSR and USA still had a huge Nuclear Bomber fleet that used free fall bombs . A mass raid on the main land USA could be made up of anything up to 1000 bombers . The Genie missile used by the F102 and F101 interceptors could be fired into the middle of the bomber formations where part of the formation would be destroyed by the actual blast and those in front and behind could be damaged / destroyed by the shock wave (which travelled faster than the bombers like the Tu-2 Bull and Tu-95 Bear ) . \n\nAs a concept it was sound as each F-102 could carry 4 Genie Air-to-Air missile as well as guns . The less aircraft you needed to attack a large bomber formation and the further away then the quicker you can intercept not having to build up a large fighter force to deal with them . \n\nThis was a direct result of lessons learned during the Battle of Britain where 12 groups \"Big Wing\" idea had issues . RAF squadrons would try to link up en-mass to try and hit the German bomber formations as hard as they could . While the idea seemed effective in theory many aircraft had reduced combat time as they waited for other squadrons from the group to join up and the German bombers were able to get closer to their targets before being intercepted. \n\n"
]
} | [] | [] | [
[],
[],
[]
] |
|
2109w4 | why are the russians troops that invaded crimea wearing masks and in unmarked uniforms | Isn't it a law of war that they have to wear marked uniforms? And why the masks? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2109w4/eli5_why_are_the_russians_troops_that_invaded/ | {
"a_id": [
"cg8dby1"
],
"score": [
4
],
"text": [
"Plausible deniability--Russia can say they are \"thugs\", or \"gangs\" without taking direct responsibility."
]
} | [] | [] | [
[]
] |
|
2gk7hd | 3d printing over void space | I understand the basics of 3D printing involves depositing successive layers of material. In this process, the lower layers support the upper layers. However, I've seen a lot of 3D printed objects that include portions that enclose, cover, or extend over empty or void spaces/volumes. It doesn't seem like one could print a layer over void space, with nothing to support it ... so how is it done?
(I did a search before asking, and couldn't find any questions directed to this aspect of 3D printing.) | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2gk7hd/eli5_3d_printing_over_void_space/ | {
"a_id": [
"ckjv9j7",
"ckjvhzo",
"ckjwvwd"
],
"score": [
2,
3,
3
],
"text": [
"The stuff I've seen includes some disposable support 'scaffolding' that needs to be cut out after printing is finished. Basically, they'll just print a lightweight lattice inside the void.",
"It depends on the printer. Some printers will switch to a different material called support material and print the \"void\" solid. Once the object is done printing it is soaked in a chemical solution that dissolves the support material leaving the void. Other printers like the one I have will use the original material but print that section in a zig zag pattern that is weakly connected to the object so it can be snapped off creating the void. Almost like the void is printed but perforated for easy removal. Other printers use current methods to achieve the void. Does this help?",
"For builds without support, the answer is excellent temperature control. It is possible to set the temperature of the nozzles of a 3D printer, so that it is just enough heat to melt the plastic. When the the filament is extruded, and makes contact with the air it cools and hardens. \n\nIn this object: _URL_0_ you can see the suspended parts. If you nozzle is too hot, the suspended parts in the center will sag. If your nozzle is too cool you won't be able to extrude at all.\n\nFor the most part, designers and printers will build supports, but it is possible to do so without, just significantly harder. Getting the right settings all depend on the filament you are using, ambient temperature, ambient humidity, alignment of the planets."
]
} | [] | [] | [
[],
[],
[
"http://www.thingiverse.com/thing:9804"
]
] |
|
1pbgi3 | why is it illegal to download music without paying for it when i have access to the same music for free on multimedia websites, like youtube? | Basically, it doesn't make sense to me because if the music on YouTube is free to listen to (besides your internet bill), why does it matter if I have the same music on my iPod, for example, if I have free easy access to the music anyway? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1pbgi3/eli5_why_is_it_illegal_to_download_music_without/ | {
"a_id": [
"cd0ng4p",
"cd0nhhi",
"cd0nksx",
"cd0psew"
],
"score": [
3,
15,
5,
2
],
"text": [
"Because the record companies have those videos monetized, so they still get their cut. Videos that aren't owned by the record company that have those songs just haven't been taken down yet.",
"Because artists post music to YouTube themselves, and in turn get a cut of the ad revenue and the sales that those videos generate. ",
"Yes, the artists do get a cut of the advertising money. However, the hope is that you like the song enough to click one of the \"purchase on Google Play/Amazon/iTunes\" links at the bottom, and further support artists. It's the same reason radio stations and Pandora play music, to give exposure for those songs, and profit at the same time. Even if they already are famous, the more people that hear their song, the more likely it will be a hit. This is proven by the fact that most of the songs on the albums that people buy aren't well known. This is due to the fact that they weren't popularized by YouTube/Pandora/Radio.\n\ntl;dr: They do get ad money, but it's more for exposure, so you buy the song.",
"Youtube got a license to distribute and stream the music on their website from the Studios and Record Companies. They probably have clauses that require Youtube to show ads, whose profit is given to the record companies or distributors. \n\nYour iPod does not show ads and/or there is no way in which the companies can profit from you listening to the song, so you are not licensed, and downloading it becomes illegal."
]
} | [] | [] | [
[],
[],
[],
[]
] |
|
72n2y6 | if i die and i am eligible to donate organs, who would pay for the procedure? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/72n2y6/eli5_if_i_die_and_i_am_eligible_to_donate_organs/ | {
"a_id": [
"dnjqmbj"
],
"score": [
2
],
"text": [
"Insurance pays for it through the intended recipient generally "
]
} | [] | [] | [
[]
] |
||
7p3qhf | what causes the inside of toilet tanks to appear all poopy? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7p3qhf/eli5_what_causes_the_inside_of_toilet_tanks_to/ | {
"a_id": [
"dse9cn6",
"dse9ssq"
],
"score": [
3,
6
],
"text": [
"Minerals in your water. Iron in the water sticks to the porous inside of the porcelain tank and stains it brown.",
"You sure you didn't get an upper decker? "
]
} | [] | [] | [
[],
[]
] |
||
3mu8e4 | if we know that leptin suppresses hunger and triggers fat-burning, why hasn't a leptin pill/injection been developed to treat obesity? | Just a chunky looking for some answers | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3mu8e4/eli5_if_we_know_that_leptin_suppresses_hunger_and/ | {
"a_id": [
"cvi46kn",
"cvids33",
"cvin5hk"
],
"score": [
2,
2,
3
],
"text": [
"Experiments were tried and none of them produced significant weight loss results. There is a subset of people who are leptin deficient that become very obese who benefit from leptin supplementation and lose a lot of weight. ",
"Leptin is just one cog in the wheel of human metabolism. It's extremely adaptive so it will just compensate for the abnormal leptin levels and not effectively 'do' anything. That's because the human metabolism is designed to have energy readily available and extract it quickly from whatever you eat.\nThe answer to weight loss lies therein: do more and eat less. The leptin will do its job and you don't even need any extra.",
"Leptin is not used physiologically as an acute (i.e., short-term) sensor of energy. Instead, it evolved as a \"famine sensor\" - leptin is normally secreted by fat cells, and when all of the fat is used up, leptin is no longer produced. This signals only when there is no fat, i.e., during periods of extreme famine. \n\nThis is why giving leptin as a pill doesn't work - the body doesn't really care how much there is, as long as it's present. Adding more has no effect due to evolved \"leptin resistance\". In fact, the same thing (a lack of effect when giving excess leptin to the obese) happens in all mammals.\n\n[This](_URL_0_) paper is a great introduction to the mechanisms of weight defence, but it is quite technical. Leptin is poorly understood in general media, with many positing it as the master regulator of weight maintenance. In reality, we don't really have a master regulator - we've never had to evolve a strong mechanism to stop us eating!"
]
} | [] | [] | [
[],
[],
[
"http://www.nature.com/ijo/journal/v33/n2s/full/ijo200965a.html"
]
] |
|
3hnrz7 | how do networks calculate accurate ratings if so few people have a neilson box? | it seems like nobody has one and i've never heard of anyone - even myself being offered one. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3hnrz7/eli5_how_do_networks_calculate_accurate_ratings/ | {
"a_id": [
"cu90aog"
],
"score": [
2
],
"text": [
"Neilsen ratings are getting increasingly inaccurate. They're years behind the technology people are using now. They and others like them are slowly getting better at tracking ratings across media, like streaming, VOD, Cable, etc, but I'm surprised advertisers aren't pushing them harder to get their act together."
]
} | [] | [] | [
[]
] |
|
562x8q | why and how is the brain able to "forget" tragic events and pain? | A few years ago I rolled my truck in a field about 5 times: up a small bank, through barbed wire. Since the second it happened, I wasn't able to remember what caused the accident, or the accident at all, until I got out of the truck and walked away.
Women also say that you forget the pain of child birth.
How is the brain able to do that, and why? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/562x8q/eli5_why_and_how_is_the_brain_able_to_forget/ | {
"a_id": [
"d8fwwvf"
],
"score": [
3
],
"text": [
"I'm not sure I'd call this an \"ability\". This is something that is usually *caused* rather than the brain, well, deciding to do it. \n\nThat said, there are quite a few different things that might be happening here. Your personal experience if pretty obvious trauma, during which the brain might not have *recorded* the memories in the first place. There is a delay between you experiencing something and it being encoded into long-term memory. Trauma can prevent that from happening. \n\nDifferent kinds of physical trauma can cause physical damage, which may cause a person to forget things. \n\nThere is also *temporary* traumatic memory loss, where the brain will just refuse to *access* memories which *are* there. This is usually, as mentioned, temporary. \n\nFinally, women \"forgetting\" the pain of childbirth is more a natural Human ability to focus on the positive. It's pretty common to have an inherently mixed experience, but if the positives outweigh the negatives, we tend to ignore the latter. "
]
} | [] | [] | [
[]
] |
|
6t996o | how come different parts of our body have a different tolerance to heat? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6t996o/eli5_how_come_different_parts_of_our_body_have_a/ | {
"a_id": [
"dliv63k"
],
"score": [
5
],
"text": [
"Difference in the amount of sensing nerves. Fingers are the most sensitive (if earth is a perfectly round marble, our finger can feel the cars moving just by touching it)"
]
} | [] | [] | [
[]
] |
||
4trkii | why have recent us presidential elections typically come down to swing states of ohio, pennsylvania, florida? | I'm curious as to why recent elections have come down to several swing states to decide the US presidency of late. I know that there are more states than just those, but it seems since the year 2000 those states have been heavily involved.
I understand how the electoral college functions, but what makes these states such key components? Is there a vast divide that always makes it close? Are they highly populated by more minorities of late? Curious for an answer. Thank you | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4trkii/eli5why_have_recent_us_presidential_elections/ | {
"a_id": [
"d5jmb0v",
"d5jpu2g",
"d5kskch"
],
"score": [
2,
12,
2
],
"text": [
"One framework which is useful when thinking about the electoral college is thinking about how the popular vote in each state tends to differ from the national popular vote.\n\nIf the national race is tied, it is overwhelmingly likely that Vermont and North Dakota are not also sitting at 50/50.\n\nThis is a good way of showing the partisan lean of a state's electorate.\n\nSome states, most especially Ohio, Florida, and Pennsylvania tend to not be too different from the national popular vote and are also pretty large states. This makes them overwhelmingly likely to be the states that tip one candidate over 270 electoral votes.",
"Let's say you're running for class president, and you have a class of 100 people, that are sorted into 6 big groups of friends who all vote together: \n\n- Your best friend Carl and his 19 friends\n- Your other friend Nate and his 5 friends\n- Your enemy Tom and his 19 friends\n- His girlfriend Alice and her 5 friends, \n- These other kids who you know, but aren't really close with either way, Florence and her 30 friends, Oliver and his 20 friends\n\nYou probably don't need to spend a lot of time going after Carl and Nate. They're your best friends, and they're going to vote for your pretty much no matter what, unless you really go crazy. So you'll stop by and say hi, but you're not going to spend a lot of time lobbying for their votes.\n\nThere's not really any point in going after Tom and Alice, either. Tom hates you, his friends all hate you, her friends all hate you, and no amount of time spent talking to them is going to convince them to vote for you over your opponent.\n\nFlorence and Oliver aren't really friends with either of you, they don't hate you either. They can be swayed either way, depending on which ideas they like better. So you would spend more time talking to Florence and Oliver than anyone else, since the time you spend talking to them can actually influence the election.\n\nTo translate to the real world, you're a Democrat and Carl is California, Nate is New Jersey, Tom is Texas, Alice is Alabama, Florence is Florida, and Oliver is Ohio. \n\nWhy would Hillary spend time in Alabama? She's not going to win it. Why would she spend a ton of time in California? Most likely, they are going to vote Democrat. So she spends a lot of time in Ohio, Florida, and Pennsylvania since polling shows they could swing either way, and if her case appeals to those votes she can take the election.",
"The majority of States have more voters from one party or the other that they are effectively decided before the election season even begins. (i.e The Republican nominee will win Texas, South Carolina, Idaho etc., the Democratic nominee will win California, New York, Massachusetts etc.) there's about 11 States that are relatively up for grabs. Some might lean towards one party or another, but both parties have a realistic chance to win them. Of those swing States, Ohio and Florida have a lot of electoral votes, and will usually decide a Presidential election. Pennsylvania, Virgina, Wisconsin, and Colorado have a moderate amount and contribute to the result as well. New Hamphsire is a swing state too, but they don't have very many electoral votes so they don't get as much attention. "
]
} | [] | [] | [
[],
[],
[]
] |
|
2anzef | tipping out ( delivery driver ) | So I have been working as a delivery driver for the past year. I just applied to this job and online, it says that the position is split between being a delivery driver and doing other duties, such as dishwashing, which is fine is me. On there it says that while dishwashing, the driver will be tipped out. Does anyone know what this "tipping out" means? Thanks :) | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2anzef/eli5tipping_out_delivery_driver/ | {
"a_id": [
"cix0zsz",
"cix14c4",
"cix4iq3"
],
"score": [
4,
3,
2
],
"text": [
"An amount or percentage of a server's tips that the server shares, either voluntarily or as mandated in a tip sharing or tip pooling agreement, with other employees such as bus boys, bartenders, back waiters and hostesses whose job duties indirectly assist the server.",
"[Tip out](_URL_0_). That link explains it pretty well.\n\nIt means that you get part of the tip money that the other people earn. That way you won't lose a lot of money just because you're dishwashing (or whatever) instead of delivering. \n\nThe flip-side is that when you're out delivering you'll have to give some of the tip money that you earn to fellow drivers who were washing dishes while you were delivering. ",
"It means that if you spend your whole shift doing non-delivery duties without tips, the other drivers should be giving you part of their tip money.\n\nOn the flip side, this means that *you* should be giving the in-house guys some of your tip money."
]
} | [] | [] | [
[],
[
"http://en.wiktionary.org/wiki/tip_out"
],
[]
] |
|
5ac4ll | when you deposit to a bank, does the bank just store the money | So let me explain in more detail here. When it comes to a bank accepting a cash deposit to your account and you get said amount accredited to your account what does the bank do with said money. It's not like they would want to keep billions and billions of dollars of cash stored somewhere because it was deposited. How does that all work? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5ac4ll/eli5_when_you_deposit_to_a_bank_does_the_bank/ | {
"a_id": [
"d9f9f96",
"d9f9jgn",
"d9fay9f",
"d9firjz"
],
"score": [
20,
3,
2,
2
],
"text": [
"The way modern banking works is heavily reliant on what we call 'fractional reserve banking'. When you deposit money in the bank, a portion of that money (say, 10%) is set aside and actually kept in the bank. The other 90% of the money is made available for loans from the bank. \n\nThat is, effectively, what a bank's main business is. In return for putting your money in the bank, you get some money as interest, and the bank uses your money to give out loans, which will in turn be repaid to the bank with more interest. ",
"Google \"fractional reserve lending\" \nThe simplest way I can describe it is....\nWhen you deposit money, you have access to it but, it's technically the banks. \nWhat they do, is use the money they're holding to lend to other people.\n\n Say you deposit 1000, they can lend a percentage of that 1000 to someone else, with interest, so that person can do something like start a business, buy apples from a farm to sell at market etc.\n\n This way, instead of money being a stagnant thing that sits, it allows economies to grow wealth. Provided the bank is sensible, the risk to everyone is very low but, of course, there is always risk. ",
"If you are wondering about actual cash; Individual branches have varying level of security and capacity for carrying cash depending on their need for it. As a rule of thumb you are encouraged to carry as little cash as possible and usually once or twice a week an independent security service will take cash or deliver cash to the branch (generally you get rid of the large bills and order small ones).\n\nThe independent security companies have a much more fortified approach to defending their money. The banks want to look approachable, the security companies don't, so the branding works for bank if they don't have their own \"fortresses\". ",
"Extra history are doing a series about paper money and have been talking about this sort of thing. Link to episode 1 is below, but the answer to your question is I think in episodes 3-5\n\n_URL_0_\n"
]
} | [] | [] | [
[],
[],
[],
[
"https://youtu.be/-nZkP2b-4vo"
]
] |
|
5w5brs | why does chipotle cause diarrhea? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5w5brs/eli5_why_does_chipotle_cause_diarrhea/ | {
"a_id": [
"de7f3z9"
],
"score": [
3
],
"text": [
"It's not anything specific to Chipotle. I think you'll find that most fast food chains have this reputation to at least some degree.\n\nIt's because the food is made cheaply with a lot of fat, starch, sugar, and salt, and not a whole lot else. Anyone who eats too much of that kind of food in one sitting is going to make themselves sick, and some people tolerate it better than others. And then you add to that the fact that most people will order a caffeinated soft drink, which also adds to that effect because caffeine, as a stimulant, can cause gastrointestinal discomfort as a side effect. And then all of that gets multiplied even further if you like to go out for fast food after an evening of drinking.\n\n"
]
} | [] | [] | [
[]
] |
||
5o78b9 | why is field hockey a woman's sport in the us but a men's sport in the rest of the world? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5o78b9/eli5_why_is_field_hockey_a_womans_sport_in_the_us/ | {
"a_id": [
"dch9rjt",
"dchjr6j"
],
"score": [
6,
2
],
"text": [
"There is a law in the USA referred to as [\"Title IX\"](_URL_0_) that says educational opportunities cannot discriminate based on gender. \n\nThat includes sports sponsored by schools creating a situation where \"boys\" sports can't be funded more heavily than \"girls\" sports. \n\nSo usually you get mens and womens teams for each sport (soccer, basketball, softball/baseball, etc) but sometimes there needs to be different sports. There probably isn't enough interest to field a women's football team but if you can get enough girls to join the field hockey team then you can have a balance. \n\nMaybe without Title IX Field Hockey, regardless of gender, would have never taken hold in the USA like Cricket but with Title IX it has. Title IX is one explanation for why the USA is so dominant in Women's Soccer because there was a require to develop female athletics that isn't present in many other nations including ones where Soccer is by far the dominant sport. ",
"Your statement doesn't square with results in [women's international hockey tournaments](_URL_0_) where the US has occasionally had reasonable results but has never been ranked the [best team in the world](_URL_1_). So I'm guessing women do play in other countries."
]
} | [] | [] | [
[
"https://en.wikipedia.org/wiki/Title_IX"
],
[
"https://en.wikipedia.org/wiki/Women's_Hockey_World_Cup",
"http://www.fih.ch/rankings/outdoor/"
]
] |
||
3749u4 | game theory (relating to mathematics and john nash. not video game creation and analysis) | **edits:**
Super helpful explanatory videos:
posted by /u/ruk_hai -- [vid](_URL_0_)
posted by /u/justanothergamer -- [vid](_URL_3_)
playlist posted by /u/mylibertarianaccount -- [vid](_URL_1_)
excellent text explanation by /u/esbio -- [post](_URL_2_) | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3749u4/eli5_game_theory_relating_to_mathematics_and_john/ | {
"a_id": [
"crjkgyz",
"crjkkqv",
"crjkmqm",
"crjkoq4",
"crjkt4g",
"crjl9j7",
"crjloef",
"crjmcwo",
"crjmmuq",
"crjn3e5",
"crjojlj",
"crjqgef",
"crjqgxi",
"crjqopg",
"crjr9tj",
"crjszj0",
"crju000",
"crk5i0q",
"crkeyyw"
],
"score": [
871,
12,
7,
130,
2,
9,
28,
4,
2,
86,
12,
3,
172,
2,
5,
2,
3,
2,
2
],
"text": [
"Game theory is a mathematical analysis of how logical players should behave in a game to maximise their expected reward bearing in mind that everyone else is trying to maximise their expected reward.\n\nThe applications in the real world can be \"Where should I put my shop?\" because you want to get the most customers but everyone else is also trying to get the most they can.\n\nThere is also the famous Prisoner's dilemma \"Should I rat out my partner before he tells on me?\"\n\nSometimes we get situations called \"Nash Equilbriums\" where no player can improve their lot by changing decision if no one else changes. In the prisoner's dilemma it's not good that both you and your friend will go to jail but you certainly don't want him to run off with the stolen money to the bahamas while you rot so you both stick with telling the police on the other.\n\nHere is a scene from the film where John Nash thinks of game theory while at a bar trying to get girls. It's debateable however whether what is described is an equilibrium as the last person can get the blonde.\n\n_URL_0_",
"Imagine two people with buttons (a yes button and a no button). There are two possible actions for the two people to make (yes or no) and three outcomes. If they both press yes. They both lose. If they both press no, they both win, if they pick opposite answers the one who pressed yes will win. Its basically a numbers game, trying to determine your best odds on the possible outcomes\n\nThen this is applied to everyday actions. Especially political. For example the cold war, but also everyday campaigns and elections",
"A team of 3 guys run into a team of four girls. All three guys are a 6. and the girls are a 5,5,5,10. all three guys work independently and go after the hotty(10). in doing so they all fail. However if they changed their strategy and all went after the 5's. they would be working together to accomplish their independent goal of getting laid. thats from the movie a beautiful mind.\n\nI dont even know John Nash. Never seen him in real life or a photo. but to hear of his passing in such tragedy is sad. life can be so cruel and unforgiving.",
"In a nutshell, strategic thinking. A simple example could be penalty shootouts in soccer. If you are the shooter, do you shoot left or right? Maybe you like shooting to the right, so it's an easier shot. But the goalie knows that you like shooting to the right, so he'll jump to the right. But you know that he knows, so you go left. But he knows that you know that he knows...and so on.\n\nGame theory gives a mathematical framework for thinking about these kinds of situations and possibly coming up with an answer. A solution for this penalty shootout, for instance, might be to just mentally flip a coin.\n\nGame theory has its origins in WWII and the Cold War, where instead of penalty shootouts we might think of nuclear missile strikes and defense. As applied to economics, it might be applied to competition between firms. For instance, two competing pharma companies might have to choose whether to put their R & D resources into one drug or the other depending on what the other company chooses to invest in. \n\nNash's insight was, broadly speaking, showing that formulations of these competitive situations have stable solutions that we can calculate.",
"Real life has a lot of problems that math attempts to solve. One of the big ones is how people will react to decisions, inclusive of the decision itself. This may be a bit complicated, but consider the following:\n\nYou want to open a store. If you do this, other people will see your store and may open their own, creating competition. Also, opening the store may be a bad idea because it may not be successful. Lastly, someone else opening their store first may be beneficial because you could see what they did wrong and do it better, being more successful than if you started in the first place.\n\nGame theory is taking this problem (should I open a store?) and turning it into a game with rules and weighted outcomes (10k revenue per year = 1 point, competition = -5 points, etc) and processing it to see what the optimal solution (yes/no/wait) is and if there is a way in which you can \"play\" for a better outcome.",
"Game theory is the analysis of what a person should do in a situation that involves another person.\n\nIt can be applied any situation that has at least 2 people interaction, from markets, to dating, to social interactions. ",
"Game Theory is an incredibly broad field, and, though this is reddit, you're not going to get it all explained. However, I'll try to give you a concise overview.\n\nGame theory primarily deals with decision making, i.e. choosing between different options (duh), and the effect this will have on the outcome. It also includes the study of how **rational** decision-makers interact in their quest to get the maximum reward out of a situation. The rational bit is important, as we must assume that all actors in game theory problems will make the best decisions for themselves based on the information to which they have access.\n\nFor a more relatable example of a problem in game theory, take the prisoner's dilemma. In this example, two prisoners have been arrested **separately** for a minor offence. However, the prosecution suspects (he has no hard evidence) that they have each committed much more serious offences (robbery vs DUI), and that they have **collaborated** in committing the more serious offence.\n\nThe prosecutor interrogates each prisoner separately (i.e. they have no **knowledge of the other's decisions**) and offers each prisoner a plea deal, where they can admit to committing the crime, thus implicitly incriminating the other.\n\nThe minor offence carries a penalty of 3 years in prison. However, by accepting the plea deal, they get a 1 year sentence, as long as the other does not accept the deal (because then the prosecutor can take the case to trial and get a major conviction, 20 years in this case). If they both confess, they both get 2 years, as they have both cooperated.\n\nIn the following table, we can see the decisions of each of the prisoners (prisoner A in left column, prisoner B in top row). We can also see the outcomes (prisoner A *italic*, prisoner B **bold**).\n\n| |Confess|Deny|\n|:--------|:-|:--\n|*Confess*|*3 years*/**3 years**|*1 year*/**20 years**\n|*Deny*|*20 years*/**1 year**|*2 years*/**2 years**\n\nFrom an outside perspective, the optimal choice seems obvious - they should both plead not guilty on the count of robbery. This is called the *globally optimal scenario*.\n\nHowever, we must remember that they have **no information** of the other's actions. In this case, the rational option for each prisoner is to confess. This is what we call a *nash equilibrium*, which is where each party has picked the optimal alternative, given the possible decisions the other party can make.\n\nFrom A's point of view (left column, italic): Let's assume B has confessed. Then the best option for A is to confess to the serious offence as well (3 vs 20 years). Then let's assume that B has pleaded not guilty to the serious offence. Now, if A confesses, he will get 1 year, and if he does not he will get 2.\n\nWe have seen that in a situation where each party has limited information about the other's decisions, the best decision (both deny) is not the rational decision, even if both parties act completely logically.\n\n**EDIT**: As /u/ubernuke pointed out, the payoff listed in the table is wrong, though the one in the explanation below the table was correct. Now fixed!\n\nIncidentally, my \"more ELI5\" explanation was correct, while this one was wrong. Maybe I should go and (partially) decapitate myself with a shovel.",
"This is going to be more like ELI18, but I think it's worth people really understanding what game theory is and what Nash did.\n\nGame theory is the theory of strategic play. This can include situations in which all parties aim to cooperate (\"cooperative games\") and in which parties don't cooperate (\"non-cooperative games\"). Game theory focuses on questions like: what outcomes can be sustained in which all players know other players' strategies but do not regret their own. (A strategy here is defined as a plan of action, not necessarily an action. For example, when playing rock-paper-scissors, a strategy might be to choose R P or S at random.)\n\nJohn Nash did not invent game theory (this is probably best attributable to Von Neumann in his \"Theory of Games\"). Instead, Nash had an incredibly simple but brilliant insight: if we define a function that maps opponent strategies to best responses to those strategies, we can equivalently define an equilibrium as a \"fixed point\" of that function. (A fixed point is an x for which f(x)=x. So, an equilibrium is where everyone's strategy is their best response to everyone else's strategy.) Thus, Nash was able to leverage mathematical techniques from fields such as topology (e.g., Brouwer's Fixed Point Theorem and Kakhutani's Fixed Point Theorem) to demonstrate the existence of equilibria in large classes of games. More broadly speaking, by characterizing games and their equilibria in terms of mathematics, Nash made it easy for economists to apply the tools of mathematics to figure out optimal strategies, rationalizeable outcomes, and equilibria.\n\nSource: I'm a PhD student in economics at a top university.",
"In case this post is just a coincidence and wasn't inspired by the recent news: [John Nash and his wife were just killed in a car accident.]( _URL_0_)",
"There have been a bunch of amazing responses, but not a ton of explanations like you're 5, so I'll just give you a SUPER simple way to think about it (that's also a great way to teach your children about being fair, hehe);\n\n- You have a candy bar that you and your friend are going to split. If you just break it in half, you potentially risk the argument of which half is the \"bigger\" half (any of us who've had siblings have been there). So you do this -- You say to friend \"Hey, *you* get to split the candy bar in half...but *I* get first pick at which piece I want\".\n\nSee how that works (and also relates to everyone elses explanation)? Your friend, knowing that he wants to maximize the amount of candy bar he gets, but he also knows that you get first pick, so if he cut it in a 70-30 fashion you'd just choose the 70% piece and he'd be at fault for his own losses. This forces him to cut the bar in a 50-50 manner. :3\n\n",
"Game theory is thinking \"If I do this, he'll do that, but then I'll do this...\" and taking that line of thought to its conclusion. ",
"Game Theory is the study of decision making in situations where the decisions of others influences the consequences of your decisions. The most famous illustration of this is the Prisoners' Dilemma, which nobody in this thread has yet adequately explained.\n\nTwo criminals are suspected of a serious crime (murder) and caught in the act of a minor crime (robbery). They are arrested at the scene of the robbery and taken to be questioned **separately**. From this point on the criminals cannot communicate with each other.\n\nThe investigator offers them each a deal, the same deal. They can either testify that the other was involved in the murder, or keep quiet. \n\nIf they both keep quiet, they both serve 1 year in prison for robbery and the murder charges are dropped.\n\nIf one keeps quiet and the other testifies, the one who testified will go free and the other will go to prison for the murder for 30 years.\n\nIf they both testify against each other for the murder, they both go to prison for 20 years.\n\nObviously if the criminals could communicate and make their decision together, they would choose to both keep quiet and serve a year. However, somewhat paradoxically, if both act rationally and in their own best interests (we assume that they don't care about the other guy's sentence) they will both end up in prison for 20 years.\n\nFor both criminals, testifying is a *strictly dominant strategy*. Whatever the other guy does, each criminal is better off testifying. If he keeps quiet, you save yourself a year by testifying. If he rats you out, ratting him out as well saves you 10 years off a 30 year sentence.\n\nBecause of this, both criminals will testify and both will serve 20 years. This is called a **Nash equilibrium**. A Nash equilibrium is a situation where no player can change strategy to improve their payout, given the strategies of other players. \n\nWhile both players keeping quiet is best for both overall, it isn't a stable equilibrium so it won't happen (assuming both players act rationally). From this situation both players are individually better off changing their strategy so it can't be a Nash equilibrium.\n\nGames can get much more complicated or even simpler. Sometimes games are repeated which changes behaviour and equilibriums. The assumption is always that players act 'rationally' but, when these games are tested experimentally, people rarely do. I'd recommend reading around, it's a really interesting area of mathematics and economics.",
"Suppose you are at a stadium. Everybody is sitting down and enjoying the game. If you stand up, you can improve your visual, but people behind you won't be able to see the game, so they will force you to sit down. This is one Nash equilibrium condition.\n\nBut now suppose that a lot of people will ignore peer pressure and stand up. There will be a tipping point where sitting down will be too disadvantageous and everybody will be forced to stand up to see the game, and if you sit down you will have a loss. This is another Nash equilibrium.\n\nObserve how the two equilibria are not equivalent (watching a game while being forced to stand up is more unpleasant than watching while sitting, and your visuals won't improve if everybody else is also standing), and you can't get out of either of them without a simultaneous, coordinated action. ",
"In addition to the other explanations, the following simple example brought Game Theory to life for me: \n\nImagine that you are manager at a gas station, and there is another gas station right next to yours. The two look very much the same and offer the same services. How can you make sure customers come to you rather than your competitor? \n\nOne of the first things you may think of is to lower your prices. \n\nHowever, to make a proper decision you need to consider what your competitor will do. If you lower your prices your competitor has no choice but to lower their prices as well. As a result both of you will make less profit. \n\nGame theory deals with decision-making while taking other players' decisions into account as well. The situation described above is one of many 'games', and each competitor is a 'player'. There are many others like it, and game theory addresses how these games are solved, i.e. what the optimum decision is for each player. ",
"Most of the comments here are really good, but I'd like to give an even simpler take. \n\nGame Theory complicates the way we might be tempted to simplify competitive systems. The naive version of a capitalist economics holds that a capitalist system will gravitate toward optimal prosperity (perhaps under certain ideal conditions). [And the naive version of evolutionary theory holds that life forms will develop into the strongest and most sophisticated possible forms. -- Edit: I was corrected on this.]\n\nWe know that these implications aren't right, even making a few idealizing assumptions. But it's hard to understand why without completely abandoning a mathematical study of these systems. Or at least, it was before Game Theory. Game Theory examines the general framework of a competitive system without assuming that each step in the right direction is an improvement in itself. \n\nGame Theory represents actions (especially the choices of different players) in an abstracted space, with payoffs associated with each. A critical concept is an equilibrium. An equilibrium is a stable position in that space, where each actor wants to stick with that particular action. The main moral in Game Theory is that these equilibria can take place where the payoffs are pretty bad--that's the point of the Prisoner's Dilemma example. With the tools of Game Theory, we can be realistic about competitive systems but still study them in a rigorous mathematical framework.",
"The [Golden Balls game show]( _URL_0_) really sums it up nicely. Hilarious video. ",
"Game theory is, in it's simplest form, just a calculation of the best interests of individuals in a transaction or a set of transactions, and the resulting pattern of behaviour of players involved in such transactions based on their best interests. Much of game theory is unintuitive to people because it is highly non-linear.\n\nAs others have pointed out, probably the most famous \"game\" of game theory is the Prisoners Dilemma. It this circumstance, you have an opportunity of exchange with another individual. If you both cooperate and provide each other with value, you both get some intermediate value from the transaction. For example, you are buying a car from somebody in exchange for cash. If you both screw each other over, you are both worse off, i.e., you give them counterfeit cash instead and they give you a beat up lemon instead. But, if one of you cooperates (gives the goods at full value) and the other \"defects\" (screws the other over), you can gain the most and the loser will gain the least. That is, you get a good car and keep your real cash and they get counterfeit crap, or in reverse they get good cash, keep the good car, and give you a beat up lemon in exchange. \n\nThe result of such analysis is surprising to some. If you think the other person will cooperate, you are best to screw them over, as you'll gain the most that way. If you think the other person will defect (screw you over), you are also best to defect against them (screw them over). So either way, you are best to screw them over. Likewise, from their point of view, they are best to screw you over. So you both screw each other over out of individual best interests even though, had you both collaborated in good faith, you would have both been better off. And, even given a do-over the result is the same.\n",
"Game theory was originally created to predict rational moves (plays) in poker.\n\nIt was extended from its innocuous beginnings and used during the cold war to maintain an uneasy standoff between America and Russia by attempting to predict a set of \"plays\" that would convice Russia that a war was unwinnable (mutual annihilation).\n\n John Nash took the idea of stability through mutual mistrust and used it as a simplification of human behavor that basically says we are all self interested beings that distrust everyone all of the time and are in hostile competetion. \n\nHe was infamous in the Rand Corperation where he worked inventing cruel games to test his hypotheses, the most famous of which was called \"Fuck You Buddy\" where the only way to win was to completely betray your partner. \n\nIf you want to know where modern predatory capitalsm comes from-John Nash is your man! He was diagnosed as a paranoid schizophrenic, heard voices and was comitted.\n\nThere is a great explanation by Adam Curtis in [Part 1 of The Trap (Fuck You Buddy) ](_URL_0_) where John Nash is interviewed about ti. ",
"This is too late not to get buried, but my personal favorite example: The Rock, Paper, Scissors Sex Lizards.\n\nThere's a species of lizard that have three genetic \"strategies\" running through the male population, called \"Aggressive,\" \"Defensive,\" and \"Troubadour.\"\n\nDefensive lizards claim a little territory and a small number of mates, and keep a close eye on them. Aggressive lizards claim a huge territory and a large number of mates, and just try to spit out as many children as possible. Troubadours claim no territory, but go onto other lizards' territory and steal their mates.\n\nIf you have a mixed population of Aggressive and Defensive lizards, the Aggressives will out-breed the Defensives, If you have Aggressives and Troubadours, though, then the Aggressives are too busy defending territory to protect their mates, and the troubadours do more breeding with less expended effort. Troubadours and Defensives, however, leave the Troubadours with no un-defended mates to go after.\n\nSo, these lizard populations fall into a Nash equilibrium where each individual lizard does about as well with any strategy. "
]
} | [] | [
"https://www.youtube.com/watch?v=UkXI-zPcDIM",
"https://www.youtube.com/watch?v=iZKErrvVMaY&list=PL76B0EB6DDFC42D02",
"http://www.reddit.com/r/explainlikeimfive/comments/3749u4/eli5_game_theory_relating_to_mathematics_and_john/crjqgxi",
"https://www.youtube.com/watch?v=jILgxeNBK_8"
] | [
[
"https://youtu.be/2d_dtTZQyUM?t=1m10s"
],
[],
[],
[],
[],
[],
[],
[],
[
"http://www.nj.com/middlesex/index.ssf/2015/05/famed_a_beautiful_mind_mathematician_wife_killed_in_taxi_crash_police_say.html"
],
[],
[],
[],
[],
[],
[],
[
"http://m.youtube.com/watch?v=S0qjK3TWZE8"
],
[],
[
"http://www.disclose.tv/action/viewvideo/145347/The_Trap_Fuck_You_Buddy_BBC/"
],
[]
] |
|
3eqri1 | why does it seem that there are more news about police brutality/malpractice than actual criminal news in us? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3eqri1/eli5why_does_it_seem_that_there_are_more_news/ | {
"a_id": [
"cthi84t",
"cthi8lu",
"cthi91t"
],
"score": [
3,
2,
3
],
"text": [
"Easy it's a one word answer. That word is money. The media can sell more commercials now a days with police brutality than just regular criminal brutality. ",
"News stations don't report news, they report stories that will sell to the biggest audience. People don't tune in for the typical murder, they tune in for police brutality though. It is a hot topic and news stations want the attention.",
"'Number of news stories about a topic' is not the same as 'number of instances of topic'. There's no news stories about cats having dinner, but I assure you cats eat all the time.\n\nNews media pick stories that will sell well. The reason there are so many stories right now about police brutality is that people want to talk about it. Now, that doesn't mean that police brutality isn't a problem, it certainly is. But you should never rely on the media for statistical information of any kind, and especially never treat their discussion frequency as some kind of statistic about how often a problem comes up."
]
} | [] | [] | [
[],
[],
[]
] |
||
2kv89i | why are buildings in pripyat in ruins? | So I'm watching a littleYouTube documentary about Chernboyl (Czarnobyl by TubeRaiders if anyone Polish is interested).
I noticed that in all the buildings in Pripyat, the interiors are in ruins. Why is this?
Peoples' possessions are still on the floor and on shelves, but bookshelves and wardrobes have been tipped over, there's rubble all over the floor, etc.
You'd think the buildings would be nicely preserved, right? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2kv89i/eli5_why_are_buildings_in_pripyat_in_ruins/ | {
"a_id": [
"clp0hff",
"clp0to2"
],
"score": [
2,
3
],
"text": [
"They are in a state of disrepair. \n\"50,000 people used to live here... Now this place is a ghost town.\"\nGood mission.",
"No, because looting. You don't die instantly from being in an area of high radiation, like parts of the Chernobyl region. We think of that as a catastrophe, but people were back at work at the plant *days* later. Insane, right? Well, no, the plant was operational for years (like, 20 years) after. Chernobyl had a full-time staff and was producing power for Ukrainians until about a year ago.\n\nThe people whose homes got looted early on were in the \"Exclusion Zone,\" a range around the plant that actually was dangerous (and still is). They left, but there were actually very few people (relatively speaking, of course) hurt by the '86 meltdown. The creepiness of the photos you see of Chernobyl is not unique to Chernobyl, it's just the fact that places that are abandoned are creepy as shit."
]
} | [] | [] | [
[],
[]
] |
|
ayi9lm | why is adding a dark theme to an app/os so hard and doesn't take just a few color changes? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ayi9lm/eli5_why_is_adding_a_dark_theme_to_an_appos_so/ | {
"a_id": [
"ei0zd3n"
],
"score": [
3
],
"text": [
"from my experience, it's the chaotic way in which designers end up serving specifications. Might be more true in web but designers don't often enough get enough time or info to plan out a theme for their project in such ways that inversions of colors can just happen on the fly and you gets palettes with too many colors that get used inconsistently in the designs that you then have to flip somehow. \n\nthings aren't defined, for instance, as background color, title color, text color, link color from the start but a humble of colors that are sometimes backgrounds sometimes links sometimes 1 shade away from every other view/page in the project making the scope of such a theme change pointlessly more difficult\n\nbased on the average client's willingness to incorporate principles of accessibility design I'd be surprised if things got better"
]
} | [] | [] | [
[]
] |
||
2dhxrt | how do people get the smooth motion moving a camera in this video? | In the [video here](_URL_0_) the camera moves in slow motion through the scene. How do they get such smooth movement when it's taking thousands of photos? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2dhxrt/eli5_how_do_people_get_the_smooth_motion_moving_a/ | {
"a_id": [
"cjpru2x"
],
"score": [
2
],
"text": [
"If you are wondering about how they get the camera to move smoothly over a period of minutes or hours, they are using a motorized camera slider, which is a track with a small motor that can move the camera along it and also tilt the camera at any speed you choose, sometimes moving at millimeters per minute. "
]
} | [] | [
"http://vimeo.com/103223164"
] | [
[]
] |
|
69lraj | what is an "outgoing introvert" and how does it differ from a regular introvert? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/69lraj/eli5_what_is_an_outgoing_introvert_and_how_does/ | {
"a_id": [
"dh7izcv"
],
"score": [
35
],
"text": [
"Basically, being an introvert describes how your energy level and ability to recharge changes when experiencing social interactions. Introverts are drained by social interaction and need alone time to recharge.\n\nBut this is different than being shy. Shyness is how you confront the social interaction. Outgoing or shy has nothing to do with your energy levels.\n\nYou can be outgoing but still get drained by the interaction. \n\nI am an introvert. My favorite activity on a Saturday night is to stay home and do something familiar...like read, scan the internet, watch a movie....alone. But, I am not shy. If an opportunity at work comes up that requires a speech or interacting with customers, everyone's head turns to me because they all know I will nail it! But afterwards, I hide in a hole for 36 hours to recharge. I am outgoing and I am definitely an introvert."
]
} | [] | [] | [
[]
] |
||
a22738 | explain what’s happening here causing the bread to effectively vacuum seal itself | [bread front and pack](_URL_0_)
Can anyone explain what’s happening here? The packet on the left has been left under the stairs for a few months, taken out and now all the air seems to have disappeared from the packet. And on the right is a fresh packet of the gluten free bread rolls. Maybe it’s an ingredient in the bread? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a22738/eli5_explain_whats_happening_here_causing_the/ | {
"a_id": [
"eauj8ee"
],
"score": [
2
],
"text": [
"Expired? Mouldy and decomposing? "
]
} | [] | [
"https://imgur.com/gallery/WMcDmT7"
] | [
[]
] |
|
1b1m1r | why can't you give blood if you've received blood? | I've always wanted to give blood so I looked on the UK blood donor website and one of the items which would disqualify you from donation was if you had received or think you might have received blood since 1st January 1980. I suffered a ruptured appendix and subsequent blood poisoning in 2003 so I have definitely received blood after 1980. Why is this the case? I know AIDS/HIV was beginning to become recognised around that time. Is the risk of AIDS/HIV why I can't give blood? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1b1m1r/eli5_why_cant_you_give_blood_if_youve_received/ | {
"a_id": [
"c92q9hg",
"c92t06w"
],
"score": [
56,
12
],
"text": [
"Actually no, in your case it's about [mad cow disease.](_URL_0_) ",
"In general, it's to stop blood-borne disease having a ready-made transmission vector through transfusions (which are conveniently often given to people who are coincidentally not in the best of health). Blood gets screened as well, but it's possible that something could slip past (and some blood-borne diseases don't have effective tests which can be performed on raw blood). Without the ban, you could have received a bloodborne disease which doesn't present symptoms at the time of donating from your received blood, give a pint every few months, and unwittingly amplify the original contamination hugely. With the ban, the worst that can happen is one non-presenting carrier can infect one recipient. \n\nSpecifically, /u/kcell has your answer. "
]
} | [] | [] | [
[
"http://www.redcrossblood.org/donating-blood/eligibility-requirements/eligibility-criteria-alphabetical-listing#arc5"
],
[]
] |
|
80n7cy | why does any injury hurt more the next day | Why does the pain of some injury manifests itself after the body has rested for a prolonged time instead of time when the injury actually occurs. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/80n7cy/eli5_why_does_any_injury_hurt_more_the_next_day/ | {
"a_id": [
"duwq6oz"
],
"score": [
6
],
"text": [
"Your body is repairing itself. It may be swelling due to inflammation as well.\n\nAlso the endorphins that your body released at the time of injury are now gone, so no more natural pain killers.\n\n"
]
} | [] | [] | [
[]
] |
|
175opg | why should mushrooms be brushed off rather than washed, before cooking? can you really taste the difference? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/175opg/eli5_why_should_mushrooms_be_brushed_off_rather/ | {
"a_id": [
"c82fohf"
],
"score": [
2
],
"text": [
"People say not to wash mushrooms as they may take on water and lose flavour. However mushrooms are mostly water and washing them shouldn't be a problem anyway. Brushing off rather than washing is a myth."
]
} | [] | [] | [
[]
] |
||
khys2 | stocks that don't pay dividends | Why people buy stocks that don't pay dividends? I know that some of then allows a vote but in a big company you would need spend really big money to make a diference. For example, Apple. Why should I buy Apple stock? Why would I want such a small part of such a big company? I would understand if you are buying 10% or 25% of the company but if you are not a big investor aren't you just a part of a scheme? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/khys2/eli5_stocks_that_dont_pay_dividends/ | {
"a_id": [
"c2kduwk",
"c2ke0gh",
"c2kduwk",
"c2ke0gh"
],
"score": [
2,
3,
2,
3
],
"text": [
"You can make money on shares that don't pay dividends by buying them at one price and selling them for more. \n\nIf you buy a share of The Company for $100. Six months later, the market now says that the same share would cost $135. If you sell that share, you get $135 - meaning you just made $35.",
"There are two types of earnings you can have by holding stocks: capital gains and dividends.\n\nCapital gains are when you buy the stock at one price and sometime in the future you sell it for more. Thus, if you sell it for less, you have a capital loss.\n\nDividends are when the company pays part of its earnings out as cash to its owners (stockholders).\n\nWhile dividends may look like the obvious reason to invest in a company, they are actually used more often by mature companies that aren't growing any longer. When they have earnings, they don't have much to invest in, so they pay them out as cash.\n\nA company that doesn't pay out dividends is generally using its earnings to grow.\n\nSo one way to look at it is that if the company is reinvesting its money (and not paying dividends) it is because it believes it can make good returns on that money, and if it is paying out dividends it is because it doesn't have a better use for the money other than to give it to the owners.",
"You can make money on shares that don't pay dividends by buying them at one price and selling them for more. \n\nIf you buy a share of The Company for $100. Six months later, the market now says that the same share would cost $135. If you sell that share, you get $135 - meaning you just made $35.",
"There are two types of earnings you can have by holding stocks: capital gains and dividends.\n\nCapital gains are when you buy the stock at one price and sometime in the future you sell it for more. Thus, if you sell it for less, you have a capital loss.\n\nDividends are when the company pays part of its earnings out as cash to its owners (stockholders).\n\nWhile dividends may look like the obvious reason to invest in a company, they are actually used more often by mature companies that aren't growing any longer. When they have earnings, they don't have much to invest in, so they pay them out as cash.\n\nA company that doesn't pay out dividends is generally using its earnings to grow.\n\nSo one way to look at it is that if the company is reinvesting its money (and not paying dividends) it is because it believes it can make good returns on that money, and if it is paying out dividends it is because it doesn't have a better use for the money other than to give it to the owners."
]
} | [] | [] | [
[],
[],
[],
[]
] |
|
2xfbu2 | what's the point in distributing a video as a .rar file rather than an .avi or .mp4 file? | As far as I can tell, it just adds a pointless extra step where you have to extract the data. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2xfbu2/eli5_whats_the_point_in_distributing_a_video_as_a/ | {
"a_id": [
"cozm23l",
"cozm8mk"
],
"score": [
3,
3
],
"text": [
"A rar can be split into several parts. So if a download fails part way through you just have to retry a part instead of the whole thing",
"It prevents people from streaming your video by hotlinking in addition to jedwardsol's answer about multiple parts."
]
} | [] | [] | [
[],
[]
] |
|
34mahh | why does hate speech and whatever motives behind it still exist? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/34mahh/eli5_why_does_hate_speech_and_whatever_motives/ | {
"a_id": [
"cqvzwv5",
"cqwe6mh"
],
"score": [
6,
2
],
"text": [
"Humans spent the first 200,000 years of their existence in tribes.\n\nNon-human hominids spent millions of years before that in tribes.\n\nHumans have tribalism evolutionarily ingrained in their brains, there's our \"tribe\" and there are other \"tribes\" that we treat differently. Anyone who says they've *never* had a racist thought cross their minds is a liar.",
"There are two underlying issues behind your question. \n\n1. People naturally identify with a tribe and like members of the tribe and dislike \"others\". This could be the opposing sports team, immigrants taking jobs while your brother can't find one, the ethnicity your people fought with against in the last war. In those cases, the emotion is very negative, and that colors interactions with them toward name calling. \n\n2. Too many liberals are labeling opposing viewpoints as \"hate\". To debate whether affirmative action is good or bad by pointing out that promoting black kids to more competitive schools only to drop out, in the name of diversity, when more would actually graduate if they went to state school - that too often gets labelled \"racist\". Oppose illegal immigration because it undermines respect for immigration law, tax law, identity theft - get called racist. Say you don't like Hillary Clinton's policies, get called sexist. (I've been told that, as a woman, by another woman. The response that I might support Carly Fiorina was still deemed sexist, because she's Republican ...) \n\nSo one reason why \"hate speech\" seems to be prevalent is because debate is labeled hate, disproportionately by the left. \n\nThe other reason is that the most irrational and trolling people in the world can spend hours online trolling others for entertainment, either appearing to be hateful or expressing such views while the rest of society actually contributes. That means the extremists are overwhelmingly unemployed and trolling, creating a disproportionate number of comments compared to the rest of the discussion. "
]
} | [] | [] | [
[],
[]
] |
||
2tdniy | how come during olympics in beijing there was hardly any smog but in reality it's hard to see anything out there because of it? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2tdniy/eli5_how_come_during_olympics_in_beijing_there/ | {
"a_id": [
"cny2q7h",
"cny2tia",
"cny2xlr",
"cny2z8w"
],
"score": [
3,
5,
3,
10
],
"text": [
"It was there it was just not shown, but I remember the athletes talking about how they had to prepare in special conditions that would match the polluted environment ",
"My understanding is that a lot of the industrial plants emitting pollution were temporarily shutdown just before and during the games to avoid a smoggy environment. That's not to say the city was entirely pollution or smog free though.",
"Starting from July (the games was in the month of August) the Beijing Government shut down most of the industrial plants around Beijing and took half of the cars off the road for the duration of the Games (cars with plates that end in odd numbers can only drive on odd number dates, and even on even days).",
"China made huge efforts to clean up and make a positive impression for the Olympics because the world was watching. Factories were shut down, traffic was cut in half because you were only allowed to drive every other day. Even license places could only drive on even number days and vice versa.\n\nOnce the Olympics were over, factories started back up and the restrictions were lifted. "
]
} | [] | [] | [
[],
[],
[],
[]
] |
||
5egtmu | why do game developers keep stuff loaded out-of-screen? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5egtmu/eli5_why_do_game_developers_keep_stuff_loaded/ | {
"a_id": [
"dacbiy4",
"daccht5"
],
"score": [
2,
2
],
"text": [
"Moving things to different locations keeps them \"in memory\", where it's already loaded and really quick to use/move/whatever.\n\nIf stuff is deleted the second it disappears off screen, it has to re-loaded from the hard drive each time it's used, which is way slower.",
"I made a video game once. I'm not a coder, but did programming. It's much easier, from a design perpective, to lay out the whole thing, and then move the camera from place to place. But there's the second part, where even if game companies wanted to be more efficient, they'd be limited in that because they do not use custom tools. They use programs that already exist to design their video games."
]
} | [] | [] | [
[],
[]
] |
||
4dpk9i | the different military paths to becoming a civilian physician. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4dpk9i/eli5the_different_military_paths_to_becoming_a/ | {
"a_id": [
"d1t7gmr"
],
"score": [
2
],
"text": [
"Better to ask a school counselor. \n\nThere are 2 obvious ones, go into the military and get the G.I. BILL and use it to pay off college to become a physician. \n\nOr go into the military, preferably through OTC with some school under your belt majoring in medicine. That way the military only needs to to put you through some field medicine, then when you're out of the military they will pay the rest to finish your licensing and degrees. \n\nAfter either of those paths you can be a civilian physician. "
]
} | [] | [] | [
[]
] |
||
15sru1 | why are there several mandatory injections for schools? | Recently I received a notice from my school stating that I needed to receive a shot. Failure to comply would mean suspension* Is this within the school's scope of power? Also, what's the general purpose of these shots? Any alterior motives?
*The notice was given to me at school. Hopefully that clears some confusion up. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/15sru1/eli5_why_are_there_several_mandatory_injections/ | {
"a_id": [
"c7pgmje",
"c7ph1pz",
"c7pi0fg"
],
"score": [
10,
3,
2
],
"text": [
"Schools are the perfect places for diseases to spread. In order to protect the other students schools are allowed to mandate that you get vaccinated for some diseases. Some people cannot get vaccinated due to medical issues. So, having enough protected people around them creates a herd immunity where there aren't enough viable carriers for a disease to survive.",
"university is basically a giant dirty ass brothel. There are so many more ways for viruses and bacteria and bad things to get spread mainly because you're now living with people who most likely have never had to clean up after themselves (stereotype i know).",
"I wish they made them all take a flu shot yearly."
]
} | [] | [] | [
[],
[],
[]
] |
|
1f2rpy | sharia courts in the uk | They apparently they only deal with small disputes and family disputes at the moment.
But why are they allowed?
All I have heard is that they simply act to remove the rights of women in the court room. Even if it is optional surely women from Muslim communities will be forced to go even if they don't agree?
Why are we allowing such things in a so called equal society, surely everyone should be equal in they eyes of the law regardless of religion? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1f2rpy/eli5_sharia_courts_in_the_uk/ | {
"a_id": [
"ca68lhz",
"ca68oz1",
"ca69idd",
"ca6gtfz"
],
"score": [
4,
31,
5,
3
],
"text": [
" > Even if it is optional surely women from Muslim communities will be forced to go even if they don't agree?\n\nIt's possible in any circumstance for people to be forced into doing something they don't want. The only alternative to this is to force people to use government courts to resolve all their disputes.",
"They are allowed because all the Sharia court does is alllow discussion leading to a contract between the parties in question. The contract's terms are based in sharia law, but the contract is legally binding under UK law in the offer/acceptance/consideration manner that covers all contracts. They are used to settle disputes, rather than criminal cases, and anyone is free to settle disputes in whatever manner they see fit as long as they don't do anything illegal.\n\nExample: Dave lent Steve £5 a few weeks ago, but Steve has yet to pay him back. Dave wants Steve to pay £1 in interest on the debt, but financial interest is not allowed under Sharia law. A Sharia court is convened, the judgement is that Dave cannot charge interest and it is decided that Steve should pay back the £5. Dave and Steve agree to this and have entered into a contract to this effect, if Steve doesn't pay Dave back then Dave could take it to the small claims court as with any other minor, financial dispute.\n\nThe court cannot force payment, cannot impose fines and cannot imprison either of them. Both parties are free to refuse the judgement of the court or refuse to attend in the first place.\n\nIf they do coerce parties into attending, contravene anyone's rights or impose punishments then that is a matter for UK criminal law and there is already legal process in place to deal with this.\n\nThe good news is you can do exactly the same thing with your mates down the pub (accepting that inebriation can render a party unfit to agree to a contract), or you can set up a court of the Flying Spaghetti Monster.",
"I've been reading a textbook on this. I'll summarize what it says.\n\nIn the UK there are organizations, often run on a voluntary basis, that attempt to settle disputes between Muslims. They can offer mediation and such, but some of these councils are recognised as an Arbitration Tribunal. Parties sign an agreement beforehand that they accept the judgment of the tribunal, and this agreement can be enforced in normal court just like any other contract (also see Badgerfest's comment). Some cases are excluded from arbitration, such as criminal cases and certain matters of family law. \n\nIn divorce cases a sharia council will first make an attempt to reconcile the parties. Bano's research has shown that women often have a weaker position here, both because under sharia law their legal position is inferior and because they express themselves less assertively. Despite this inequality women apparently benefit from sharia councils because it gives them the opportunity to get an islamic divorce, and also because the councils can correct violent behaviour of their husbands. It is therefore concluded that women would be worse off if there were no sharia councils. \n\nRegarding your last question:\n\nI don't think the existence of these tribunals means that people are not equal in the eyes of the law. Everybody can submit a case to a tribunal, with certain exceptions as to the subject matter of the case, and courts will enforce the decision of the tribunal irrespective of whether it was a religious one. Within any society there are groups or subcultures with their own norms. Muslims are such a group, but also specific industries (for example thhe building industry) have their own norms. There are arbitration tribunals for many specific industries too. \n\nThe controvercy of the matter relates, in my opinion, to the question whether and to what extent immigrants should assimilate to a society. Should muslims adopt UK norms and values or is it ok if they continue to live and choose to be judged by their own norms (as far as this doesn't violate english law - and to what extent should the law take cultural differences into account?)? (EDIT: The existence of sharia councils shows that (a part of) the muslims in the UK have not given up the norms and values of their cultural background, even if they clash with UK norms and values. This is controversial because it so clearly illustrates the lack of assimilation that some think should be achieved.)",
"It's not a new thing. It's not a specifically Muslim thing. It's not a specifically UK thing.\n\nFor example Jewish people in America can choose (if they so wish) to have a dispute settled by [Beth Din](_URL_0_).\n\nJust like the Sharia \"courts\" in the UK, it's just a group of people sitting down and agreeing to settle their differences using the guidance of religiously-educated people.\n\nNothing sinister, nothing scary, nothing that's trying to subvert the law of the land."
]
} | [] | [] | [
[],
[],
[],
[
"http://bethdin.org/arbitration-mediation.asp"
]
] |
|
9o59tu | how does a clicking torque wrench work? | I cannot find any clear diagrams or explanations of how clicking torque wrenches work on a mechanical level. Can anyone explain (possibly with diagrams) ? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9o59tu/eli5_how_does_a_clicking_torque_wrench_work/ | {
"a_id": [
"e7rh6dl",
"e7rmy21"
],
"score": [
4,
3
],
"text": [
"On mine, the handle flexes once the set value is reached. There is a spring of sorts inside which creates resistance to keep the handle straight. You adjust the amount of force needed to \"pop the spring\" and make the handle flex by lengthening/shortening the mechanism. The mechanism makes the sound when the spring piece flips or pops. I'm not sure if spring is the exact word.",
"Here's a site I found with not exactly an eli5 but seems to be clear:\n\n_URL_0_\n\nthe setting of the torque screw pushes the spring with more or less strength to the head of the tool. The head can swivel, and if too much torque is applied, it will \"skip\" basically causing the red cube in the picture to rotate and give way under the pressure. If you imagine pressing on this cube with more force, it will be tougher for it to skip, meaning the tool will allow more torque. If the spring applies less force, the cube will skip more easily and the tool is set for less torque."
]
} | [] | [] | [
[],
[
"https://pickthetools.com/torque-wrench-work/"
]
] |
|
22rk5l | why aren't catholics considered christian? | I thought to be Christian one merely had to believe Jesus is the lord and savior, died for your sins etc. Catholics believe this. Yet when I mention this to some people, they insist Catholics aren't Christian. I understand the differences between Protestantism and Catholicism, but aren't both of them under the general umbrella of Christianity? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/22rk5l/eli5_why_arent_catholics_considered_christian/ | {
"a_id": [
"cgporr4",
"cgpoydr",
"cgpphq8"
],
"score": [
4,
3,
6
],
"text": [
"Catholicism is Christian, but are often segregated away from the rest of Christianity because they are the largest part of Christendom.\n\nSaying Catholics and Christians is like saying Dogs and Wolves. Dogs are wolves, like Catholics are Christians, it's just a slightly different flavour.",
"Catholicism is generally accepted to be a form of Christianity. They are, in some ways, the original Christians; most other sects, such as Lutherans, stem from Catholicism. Martin Luther, who some might call the original protestant, was actually a Catholic monk for some time before he tried (unsuccessfully) to reform the Catholic church. When they excommunicated him, he started the Lutheran church. Most other forms of Protestantism followed some time later. In general, any religion that teaches people to follow Jesus Christ and regard him as the savior of mankind is a form of Christianity.",
"Some Protestant Christians don't count Roman Catholics Christians as \"Christian\".\n\nPretty much everyone else does.\n\nOff the top of my head, I can think of two reasons why some Protestants believe this.\n\nFirst, Roman Catholicism and Protestantism have some pretty fundamental differences of opinion about doctrines central to the Christian faith. The Protestants in question think that these differences are significant enough to disqualify Roman Catholics from counting as \"Christian\". \n\nSecond, there's a widely recognized phenomenon in American Catholicism wherein people who have been baptized in the Catholic church continue to call themselves \"Catholic\" even though they never attend Mass (or do so only once or twice a year) and do not live their lives with any consideration for Catholic ethical teachings. To the extent that they are Catholic, it is purely cultural. The Vatican isn't very happy about this, but it still considers such people \"Catholic\" and therefore \"Christian.\" But Protestants tend to have a less institutional definition for what makes someone a \"Christian,\" and are far more willing to look at people's lives in their analysis. Such a Catholic would not count as \"Christian\" under that kind of Protestant analysis, regardless of the theological differences between the traditions. \n\nIn all fairness, the Protestants who don't think Catholics count as \"Christians\" would probably say the same thing about liberal Protestants too. They decide to call someone a \"Christian\" or not, not on the basis of belonging to a religious organization/institution, but on the basis of personal belief and conduct. In short, if you don't believe the \"right\" things *and* conduct your life in the \"right\" way, there is a significant segment of Protestantism that wouldn't consider you to be a Christian.\n\nFor the record, all I'm doing here is being descriptive. I make no comment as to whether any of this is *right*, only that it is an accurate description of how things are. "
]
} | [] | [] | [
[],
[],
[]
] |
|
mz67m | can someone eli5 how a kettle works? | Just wondering why a kettle knows when water is boiling? Can someone explain it to me, please? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/mz67m/can_someone_eli5_how_a_kettle_works/ | {
"a_id": [
"c350lyf",
"c351mlq",
"c351nx8",
"c350lyf",
"c351mlq",
"c351nx8"
],
"score": [
3,
2,
2,
3,
2,
2
],
"text": [
"When the water is boiling, the pressure in the kettle increases. This causes air to be forced out of the spout, which is designed to produce a noise when air goes through.",
"If the question is \"How does electric kettle know when to stop heating water\", then the answer is \"it has build in thermostat\". \n\nSimplest you can get is bimetallic thermostat. You get two metals fused together that each expand at a different rate. They start to bend instead of normally expanding so they breaka a circuit. \n\n\nThere are also electronic thermostats that are very precise. They respond to changes in resistance that happens when heat is applied. Very precise means also more expensive, so probably you won't see many of them around.",
"It uses something called a *bimetallic switch*. Your kettle heats the water using an electrical current. A switch is a break in an electrical circuit, which switches it off.\n\nA bimetallic switch is a switch made from two kinds of metal stuck together. One of the metals bends one way at high temperatures, while the other bends back as it cools.\n\nThe bimetallic switch is calibrated so that it bends to break the circuit when the water reaches boiling point. Once the water cools, it bends back, allowing you to switch it back one when you need to. Clever science in a simple household appliance!",
"When the water is boiling, the pressure in the kettle increases. This causes air to be forced out of the spout, which is designed to produce a noise when air goes through.",
"If the question is \"How does electric kettle know when to stop heating water\", then the answer is \"it has build in thermostat\". \n\nSimplest you can get is bimetallic thermostat. You get two metals fused together that each expand at a different rate. They start to bend instead of normally expanding so they breaka a circuit. \n\n\nThere are also electronic thermostats that are very precise. They respond to changes in resistance that happens when heat is applied. Very precise means also more expensive, so probably you won't see many of them around.",
"It uses something called a *bimetallic switch*. Your kettle heats the water using an electrical current. A switch is a break in an electrical circuit, which switches it off.\n\nA bimetallic switch is a switch made from two kinds of metal stuck together. One of the metals bends one way at high temperatures, while the other bends back as it cools.\n\nThe bimetallic switch is calibrated so that it bends to break the circuit when the water reaches boiling point. Once the water cools, it bends back, allowing you to switch it back one when you need to. Clever science in a simple household appliance!"
]
} | [] | [] | [
[],
[],
[],
[],
[],
[]
] |
|
a1tlk0 | what is a po (purchase order) and how do they work? |
My manager has asked me to arrange a purchase order for a few invoices and would like to know how they work and what they're for. Thanks everyone
| explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a1tlk0/eli5_what_is_a_po_purchase_order_and_how_do_they/ | {
"a_id": [
"eask40u"
],
"score": [
8
],
"text": [
"Purchase orders are really just authorizations from the company to purchase a specific set of products. It is an assurance to your vendor that you have permission to place the order, so the vendor can bill you later for the purchase.\n\nHow your company does that is not something we can answer - you should talk to your Accounts Payable team."
]
} | [] | [] | [
[]
] |
|
1rghfy | why do certain accents sound different in real life than how they're portrayed in movies? | For example: if you talk to someone from Russia, they sound nothing like what a Bond villain would sound like. Also, an Italian speaking English sounds nothing like what you might hear in, say, Boardwalk Empire (think typical New York Italian accent). Is it that the italian accent has changed over the years? Same with the Irish. Someone from Ireland sounds nothing like what you would hear coming from an Irish character on TV. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1rghfy/eli5why_do_certain_accents_sound_different_in/ | {
"a_id": [
"cdn1oy4"
],
"score": [
3
],
"text": [
"Because actors are fallible and don't always spend weeks with a dialect/accent coach to get it right?"
]
} | [] | [] | [
[]
] |
|
8esjpl | why is it so much easier to converse with people, strangers or friends, online than in real life? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8esjpl/eli5_why_is_it_so_much_easier_to_converse_with/ | {
"a_id": [
"dxxoxyh",
"dxxp57f",
"dxxpwxn",
"dxxrxkw"
],
"score": [
4,
2,
3,
2
],
"text": [
"On the computer you have time to come up with and think about all your responses. In real life you don’t have that luxury. You’re also probably more nervous in real life which shows ",
"IRL tone of voice, body language, facial expressions and environment (etc.) influence the conversation. Those elements don't influence online conversations.",
"We only have text to read. No facial expressions, body language, tone. Online interaction delivers very little. We read it and interpret everything else.",
"Also there’s the question of written language vs spoken language. Spoken language is spontaneous, you don’t have that much time to think and it’s much easier to blurt out things you’ll regret saying later. This doesn’t happen with written language (aka the one you use online) simply because you have time to think before you “talk”."
]
} | [] | [] | [
[],
[],
[],
[]
] |
||
59i419 | how do djs get the individual song component tracks (synths, beats, melody, etc) to make unofficial remixes that modify all of these? | I searched before posting and either the question isn't answered well, or people say the DJs get the track components from the studio with a contract -- but I'm asking new or aspiring DJs, not those that already have a contract. Is there a DAW or software setup that can extract the individual tracts from a song for he purposes of remixing?
[ edit / update ]
Somebody corrected my terminology below, and now I'm thinking the phrasing in my title and question might be confusing people. Sounds like I'm talking more about producers, not DJs? Do producers remix songs as well? or remake songs all together? Now I'm getting confused about how this all works... | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/59i419/eli5_how_do_djs_get_the_individual_song_component/ | {
"a_id": [
"d98lexa",
"d98lgaj",
"d98lwot",
"d98w314",
"d98xf9v",
"d98xnd7",
"d98xzps",
"d98zoal",
"d992aho",
"d99jicw"
],
"score": [
59,
3,
22,
3,
7,
6,
3,
2,
4,
2
],
"text": [
"Most of the time, DJs get access to the original tracks. Keep in mind most studios *want* remixes - it ultimately makes their song more popular and they get more money.\n\nNo, there isn't any software that can split music into all of its separate tracks.\n\nThere are some special cases that sometimes work. Sometimes vocals are mixed perfectly in the center channel, so you can subtract the left channel from the right channel and remove the lead vocals. That works maybe 25% of the time. There are also some plug-ins that can isolate the bass and drums. The end result sounds odd since most of the energy from middle frequencies has been removed, but it's one starting point. If you hear a remix that mostly seems to pull from the original song and occasionally just isolates some parts like that, it could have been done this way.\n\nBut yeah, if you hear a piece that seems to take all of the different tracks (guitar, synth, drums, vocals, etc.) and rearranges them in totally different ways, there's no way it was done automatically - it means the DJ got access to the original tracks.\n",
"Sometimes there are parts of a song without much background instruments where they can extract something. \n\nIn some situations, EQ tricks can make other instruments quit and leave one loud. Doesn't work all the time. Though. \n\nThen there are ones where they were actually given the stems to work off of. Probably not what you mean by unofficial. Though. ",
"Since DJing/remixing is such a large thing now, many sites now offer stems, or the separate components of a track. Stems are simply the track broken down into its core components such as srums, vocals, bassline, etc. Beatport offers these. Also, (and what I like the idea of a lot more) Splice is a good site to take a look at. Through Splice, a lot of artists are offering up their tracks completely broken down for others to download; a little more robust than beatport's offerings. These can range anywhere from just the midis for tracks, to complete track projects. Here is an example: _URL_0_!",
"In addition to the other answers (get them from the artists/producers themselves), a similar question has been asked before ([ELI5: How do DJs get acapella vocals to remix a song?](_URL_0_) by /u/LoopF) where /u/spaceicream2 gave an more or less detailed explanation on how to extract the vocals by yourself. \n\nI imagine this would work basically for most parts of a song, however it requires quite some time for polishing the extracted parts to make them sound naturally and not cut-out.",
"Simple. When you've partnered up with someone to do a remix, officially, you get the parts (stems) either wet or dry. \"Wet\" refers to the components with the same types of filters and effects originally in the song already applied to them, and \"dry\" refers to all the components of the song without any adjustments made.\n\nUnofficial remixes are a different story. Sometimes you'll know someone who knows someone who worked on a soundboard in a studio and had the pieces to rip. Sometimes you'll just have to EQ the living hell out of something to isolate the components you're looking for. Sometimes you're cutting and editing to find the little bits that work. Sometimes, most times, it doesn't work the way you want, and so what you originally started with, turns into something new as a compromise.\n\nLike anything being made from something else, it's usually messy, and the only way to clean up the process is to have a close connection to the source. This simple rule applies to nearly everything humans do.",
"There's a technique that does an acceptable job of \"extracting\" the vocal track if you have the instrumental version. If you \"invert\" the waveform of a song (flip it upside-down using software), it won't be audibly different when you play it back--HOWEVER, if you play the inverted version simultaneously with the original version, the two signals will essentially \"sum\" to zero and you'll hear silence.\n\n\nSo, taking that concept a step further, if you take the original version of a song and play it along with the instrumental version, inverting one of the tracks will essentially cancel-out (\"subtract\") what both tracks have in common (the instrumental) and you'll be left with just the vocals!\n\n\nYou can sometimes accomplish the same thing by sampling instrumental parts of the original track in the right places (if you don't have a legitimate instrument), although it generally doesn't sound as good for a variety of reasons and depends entirely on how the song is structured.",
"Depending on how simple a song is, it can be recreated from scratch with its component parts for a near match. This isn't too common, though.",
"For a few years, I independently made and sold music tracks. When making a track that utilized a sample, my partner and I would essentially do a modern version of the process you see in \"The Getdown,\" for those familiar.\nEssentially, we'd literally sit and listen to various records/tapes/CDs/etc for hours on end, hoping to stumble-upon that perfect sample. Sometimes, this was a clean beat with no vocals, sometimes it was all vocals during a musical break, sometimes it was a mix of the two. We're talking something along the lines of a .5-second to 2-second sample. Then, we would loop that indefinitely and get to work making our drumbeat, bass line, and other tracks. \nDoing this gave me a whole new appreciation for sample-based music production, especially from the 80s-90s. \nHope that helps, feel free to ask me detailed questions if you're curious.",
"You're getting DJs and producers confused. These are two different things completely. Not all DJs produce and vice versa. \nWhen remixing a song, youre given the stems by the producer to remix to re,-produce the track, this isn't DJing. DJs most of the time are just playing tracks and mixing the songs in time. ",
"It depends on the DJ. It's true that there is nothing new under the sun and likely the people who made the original track used certain samples that anyone can purchase, or used synthesizers and patches that anyone can make. In this case you simply find out what they used, and you can use the same to re-make parts of the song. For instance the Linndrum is a very famous rythym machine that was used in a lot of 80's music. Need to do Prince drum beat from Purple Rain? Get a Linndrum. \n\nOn the other hand you can try to dissect the original song. There are tricks you can use to isolate an individual instrument or passage. For instance vocals tend to be directly centered in a song. So if you subtract left channel from right channel, you are left with only sounds that were dead center, usually the singer, bass, and maybe drums. You can then use a high pass filter to get rid of the bass and drum sounds, and if you happen to catch bits and pieces of other instruments you can try to re-create the passage using bits and pieces of similar passages. Like cloning part of a photo in photoshop and using it to hide somebodies bad hair day or a bruise. \n\nYou can also use very narrow filters to get rid of everything that is higher or lower in pitch than the part you want to capture, and you can mute parts of the passage for instance if there is a drum beat etc. \n\nIf you want to get really fancy, you can remake part of the song and if you get it close enough you can invert the phase and this will cancel out that instrument in the mix. \n\nFor instance say that you want to capture just the guitar part of a song, and there are drums mixed in you can't separate. You can sample just the drum in another part of the song, or even find out what kind of drum sample it was and you can use that out of phase to cancel out the sound. \n\nIt all depends on how much trouble you are willing to go through. \n\nVery rarely, an artist will have an acapella version of a song you can get isolated vocals, or the artist themselves will share samples or individual tracks in a multitrack recording. \n\nIf it's an official remix they may just call up the artist's rep or studio and ask for the masters. \n\nSource: I do many cover songs, mashups, and remixes for fun. "
]
} | [] | [] | [
[],
[],
[
"https://splice.com/mattlange/consider-this-stems#"
],
[
"https://www.reddit.com/r/explainlikeimfive/comments/4c5suz/eli5_how_do_djs_get_the_acapella_vocals_to_remix/e"
],
[],
[],
[],
[],
[],
[]
] |
|
1p89lp | why can't neutron stars collapse just because they're made of degenerate matter? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1p89lp/eli5_why_cant_neutron_stars_collapse_just_because/ | {
"a_id": [
"cczqvy5",
"ccztawk"
],
"score": [
4,
2
],
"text": [
"I'm not sure what you're asking -- why don't they collapse into black holes, or why don't they collapse into nothing?\n\nFor black holes, a star has to start out with a certain mass within a certain size (technically, a certain radius). If the mass is greater than the limit for that size, then it will collapse into a black hole once it stops making energy through fusion -- when the fusion stops, there's nothing to hold the star \"up\" against its own gravity.\n\nA neutron star forms when there isn't enough mass to keep it squishing until it's a black hole after fusion stops. The star stops collapsing when all of the neutrons in the original star bump together, so to speak, and they can't get any closer because their own gravity isn't strong enough to make it happen.\n\nImagine it like water in a bottle with a cork in it. Turn the bottle upside down. If it has two or more gallons of water in it, that's enough weight to pop the cork and the water runs out -- voila, black hole. But if it's less than two gallons of water, the cork doesn't pop. Instead, all the water collects in the space at the bottom (well, upside-down top) and takes up as little space as possible, but there's nowhere for it to escape to after that. Hello, neutron star.",
"So you start out with a star, gravity is trying to smoosh the proton in the star together, but electrostatic repulsion is working against it and the energy produced by fusion is working against that.\n\nOnce the pressure gets too great, all the protons smash together, giving off positrons and turning into a big soup of neutrons.\n\nThose neutrons contain quarks, which also don't want to be smooshed together, and repel each other. That's what quantum degeneracy force is. If the force of gravity is stronger than that, they ceasing being quarks, and the neutron star collapses into a black hole."
]
} | [] | [] | [
[],
[]
] |
||
3rnaju | why can't we 'store up' sleep? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3rnaju/eli5_why_cant_we_store_up_sleep/ | {
"a_id": [
"cwpjjj2"
],
"score": [
3
],
"text": [
"No expert here, but I can give this a shot.\n\nBecause the body doesn't just immediately go into a good nights sleep. Your body goes through different cycles of sleep, and it takes time to get to them.\n\nThis explains the sleep cycles fairly decently-\n_URL_0_\n\nImagine if your phone took about to an hour from the time you plugged it in, until the time it started charging. Charging it for 2 hours and then unplugging it would result in only 1 hour of charging. Plugging it in again for 2 hours would give you only 1 more hour of charge, a total of 2 hours of charging. If, however, you charged it for 4 hours straight you'd have 3 hours of charge. Think of it similarly for sleep.\n\nAlthough to be fair- The sleep schedule you described would probably be okay for a lot of people."
]
} | [] | [] | [
[
"http://www.sleepdex.org/stages.htm"
]
] |
|
a7vh98 | do genetics affect our intelligence, personality or habits/hobbies? if so, how much? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a7vh98/eli5_do_genetics_affect_our_intelligence/ | {
"a_id": [
"efna1fl",
"ec6442l",
"ec67p1v"
],
"score": [
2,
14,
3
],
"text": [
"This is old, but in my wheelhouse and I'm addicted to the topic, so... \\^\\^'\n\nThe heritability of personality and intelligence has been studied with so-called twin studies - these involve taking a lot of people and comparing how similar they are to each other. If something has a genetic component to it, people should be more similar to each other the more related they are, which then lets us calculate the share of genetic influence on the trait being measured. These kinds of studies show that genetics play a large part in why people's personalities differ from each other.\n\nIn these kinds of studies, the total differences between people get allotted to three different categories:\n\n* *heritability*, or genetic effects that make people more similar to each other\n* *shared environment*, or effects that make people more similar to each other but cannot be attributed to genetic inheritance, so scientists classify them as being caused by the environment.\n* *nonshared environment*, or environmental effects that make people *different* from each other.\n\nIn studying personality in this way, one striking discovery has been made: Family environment is traditionally thought to be part of the shared environment because parents are generally consistent with their childrearing style, and the family is in any case a lot more similar than many other experiences children may have.\n\nThe shocking discovery? The impact of the shared environment is close to zero. A hasty reading would be that family environment has no effect on children's character, which we intuitively resist because it seems wrong from experience. Yet the numbers show something is worth attention. What is it?\n\nA more nuanced explanation of the numbers is that environmental effects largely serve to make people more different from each other, and similarity between family members is literally genetic, driven by the environment's reaction to the child's genetic character, and the child choosing their own environment so that it reflects their genetic temperament. \n\nParents' childrearing, if anything, serves to make children more different from each other than more similar to each other. It is not that there is no effect, but parents respond to the child's temperament when raising them, so the genes end up being responsible, kinda.\n\nThe heritability of personality traits differs a bit based on the trait, but generally 40%-60% of differences between individuals are genetic in origin. For intelligence, by adulthood that number is 70%-80%. \n\nThere's a curious phenomenon where the heritability of intelligence is actually *lower* in young children - don't remember the exact numbers, but it's lower by a ton. One explanation for the phenomenon is that as we grow older, we become more and more able to choose our own environment and what stimuli we use, as opposed to them being dictated to us by eg. our parents or kindergarten or school, and so on, and those choices seem to reflect our genetic character a ton, as far as intelligence goes.",
"Apparently yes, in a lot of aspects. \n\nCurrently my gradeschool project is to study the link between genetic and PTSD.\nWhile it's not clearly shown in human yet, studies on rodents make us think that stuff like a traumatizing event can impact your DNA and impact future generations.\n\nIn rodents, they found out that male exposed to a extremely stressfull environement in their young age would experience some DNA modification on some genes related to stress...and so would their offpsring.\n\nBut those DNA modifications are not mutations, it's epigenetic modifications (epigenetic is basically what affects the expression of some genes but don't affect the gene itself,it's very very linked to the environement. )\n\nEDIT : Forgot to add, the offspring of the male would be more resilient to stressfull situation next to normal rodents, and that without ever being exposed to a traumatic situation themselves.",
"Ill only focus on the 1st part of your question since others have answered the rest. \nYes. Your genome (your entire genetic composition) is essentially the blue print for your being so genetics factor into so much of your life its mind boggling. An eili5 version is for the most part your intelligence is passed down from your mother. Of course more comes into play. For instance your nutrient intake during the first 2 years of your life greatly affects your intellectual potential. Think of it this way. Based on your mother's intelligence you get a \"window\" of your intellectual potential. Based on your nutrient intake during this crucial developmental period depends where you will fall within that window. After that period there is nothing that you can really do to change that. I feel it is important to add that intelligence should not be mistaken for education. And that there are a variety of ways to classify intelligents. For example emotional intelligence vs the more commonly thought of problem solving intellengce. \n\nA fascinating thing about genetics is that we are discovering more and more ties to behavior every year. Infact research into genetics has advanced almost on par with technology in the past 60 years. \n-source studies biology for 5 years with a passion bordering obsession for genetics. "
]
} | [] | [] | [
[],
[],
[]
] |
||
cqliq0 | how does ice freeze upwards? | I made a tray of ice cube yesterday at work, and when I pulled the tray out, 2 of the cubes had a spike rising at a diagonal plane. No one moved the tray and it sat perfectly flat in the freezer. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cqliq0/eli5_how_does_ice_freeze_upwards/ | {
"a_id": [
"ewx785n"
],
"score": [
4
],
"text": [
"It would be best explained in drawings representing steps of the process, but I'll try do without:\n\nIt is known fact that ice is lighter than water - icebergs float only partially sunk. \n\nIt is also known fact, that if you put the water in a container (here, a single pit in a tray, a single cube) into the freezer, it will not get colder in an uniform way. The middle will maintain initial, room, temperature the longest, and the surface (and sides and bottom) will freeze first because they will cool down below zero first.\n\nYeeeet... Freezing is also a complicated process. Very complicated, with lots of extra clauses. Two I will mention here are supercooling and ice nuclei. It is possible to lower the temperature of liquid below it's freezing point (in given atmospheric pressure) and yet it will remain liquid until it gets physically shaken - and the process of freezing (crystallization) will begin around the ice nuclei in the instance. Try googling some videos about beer instantly freezing. \n\nWhatever happened in your freezer, was a process breaking the basic path of ice cube forming. The process went along some less common route and either already frozen \"surface plate\" broke off the forming cube, or water got partially supercooled and formed mini-iceberg floating around the not yet frozen cube. Whatever way, the ice was free to float - meaning some of it stuck out of the surface. And being an already existing nuclei for further freezing, it grew fast, sticking out even further. \n\nIf it stuck out diagonally, the plate scenario is more likely. \n\nOr something else happened, I just posit a possible scenario :)"
]
} | [] | [] | [
[]
] |
|
5jov6m | why do we "smile" when we cry? isn't smiling a way to show happiness? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5jov6m/eli5_why_do_we_smile_when_we_cry_isnt_smiling_a/ | {
"a_id": [
"dbhul5p",
"dbhztaa",
"dbi3sdp"
],
"score": [
6,
2,
3
],
"text": [
"Whenever this happens to me, it's usually because I'm feeling a mixture of things all at once and it can be quite overwhelming. Things like happiness, reward, relief, sadness, excitement, and maybe even a little anger or frustration all come at me and then the smile cracks and the tears flow. \n\nThis has happened to me during very happy events or experiences like getting accepted into college after *months* of trying to get in, getting straight As in all my classes this semester, learning I do not have HIV after fearing I had been exposed to the virus, learning I do not have breast cancer after a couple lumps were found, and even sometimes after experiencing an amazing yet intense orgasm. \n\nI heard the theory in one of my Psychology classes a long time ago that when we are experiencing an immense positive emotion, our bodies may release a \"negative\" emotion or tears to sort of *balance* us out again. Pretty neat!\n\nEdit: spelling",
"Its likely associated with embarrassment for crying in front of others over something that seems silly. Like as Jilltheredhedgehog mentioned when she got straight As. ",
"Smiling also squeezes the tear ducts. Have you ever heard of tears of joy? Well, some people get so happy that they literally squeeze tears out of their eyes.\n\nIf you try it, you'll notice that smiling applies pressure to your tear ducts.\n\nHope this helps!"
]
} | [] | [] | [
[],
[],
[]
] |
||
5kq70i | how does swallowing ssris or any medication get the chemicals into your brain or other body part where it's required? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5kq70i/eli5_how_does_swallowing_ssris_or_any_medication/ | {
"a_id": [
"dbpqo8k"
],
"score": [
2
],
"text": [
"It is the same way food is processed. It is broken down and absorbed by the digestive tract, then distributed throughout your body via your bloodstream. Medications do not target a specific region. "
]
} | [] | [] | [
[]
] |
||
asf0pz | what does it mean to plea “no contest?” | What does it mean when someone pleas no contest in court? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/asf0pz/eli5_what_does_it_mean_to_plea_no_contest/ | {
"a_id": [
"egtst24",
"egtsvqc"
],
"score": [
10,
5
],
"text": [
"Basically it means, \"I'm not pleading guilty, but I can't or won't fight the charges.\" Functionally, the court operates as if the defendant plead guilty, but the plea can not be used against them in any future proceedings; for example, if you plead guilty to a traffic violation that caused an accident, that guilty plea can be used against you in civil court as an admission of fault, while a no contest plea can not.",
"It means they don't admit to the charges, but they also won't put up a defense. In practice, it's the same as pleading guilty, except that you aren't automatically subject to civil penalties.\n\nLet's say you run over somebody with your car and kill them. This generates a manslaughter charge; and the person's family may also sue you for damages. If you plead guilty to manslaughter, this will be used in the lawsuit against the person's family as evidence of your guilt. On the other hand, if you plead no contest, then the person's family must provide their own evidence that you are guilty of manslaughter."
]
} | [] | [] | [
[],
[]
] |
|
a6x19v | how does a brain aneurysm kill you? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a6x19v/eli5_how_does_a_brain_aneurysm_kill_you/ | {
"a_id": [
"ebyoki0",
"ebyq4rp"
],
"score": [
8,
3
],
"text": [
"Oxygen is like food for cells. They start dying really quickly when there's no oxygen. See how long you can hold your breath for. Now, we are our cells, if they start dying so do we.\n\nBlood transports oxygen to your cells. If your blood supply is cut off, you die. An aneurysm is what happens when a portion of the vessels that cary blood begin to expand. Just as inflating a balloon thins the walls, so does our vessels. \n\nI know the name sounds alarming but most of the time aneurysm don't cause any health problems. Many people live their whole lives without even realizing they have one. The danger is in the fact that it could burst. The exact risk is in the size and extent of the aneurysm. Keep your heart rate low and your blood flowing smoothly and you won't need to worry about aneurysms. ",
"Aneurysm is a balooning of a blood vessel because the walls have become weak. If it bursts it will start leaking blood. There is only limited room in your skull, the blood will push up against the brain. \n\nAlso, if the vessel bursts then whatever area it was supplying is gonna die"
]
} | [] | [] | [
[],
[]
] |
||
38leqj | what events led up to the tiananmen square massacre | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/38leqj/eli5_what_events_led_up_to_the_tiananmen_square/ | {
"a_id": [
"crvxu9r",
"crvyr0t"
],
"score": [
3,
2
],
"text": [
"The Soviet Union collapsed without triggering a bloody revolution. Despite the efforts of the communist party in China, word spread about the Soviet collapse and it became common knowledge. In China, the idea that the communist party could be removed \"peacefully\" fired the imaginations of a lot of people (especially young people with no direct experience of the Cultural Revolution, the great famines, or WWII).\n\nStudents organized in Beijing, and eventually at many large cities across the country, calling for the replacement of the communist system with a western-style democratic process. Those students were joined by increasingly large numbers of the emerging Chinese middle class.\n\nThe communist leadership tried to defuse the crisis and was split between those who wanted to try to find an accommodation with the protestors and those who wanted to put the protests down with violence. Eventually the momentum of the protests grew so powerful that the leadership elected to go with forceful repression. They considered it an existential moment (as in, if they didn't act, the communist party would cease to exist in the same way it had in Russia). The hardliners believed that the Soviets had made a grave error by not cracking down on dissent and protest and that was the reason the USSR had dissolved. They were determined not to see a repeat in China.\n\nThe military was ordered to go into the protest zones and break up the protests and arrest the protest leaders. Some units refused - a shocking development in a communist-run military and an indication of how right the hardliners were about the close-run nature of the thing. If they'd waited a bit longer it might have been too late to stop a revolution. Eventually enough forces were assembled willing to follow the leadership's orders, and they moved into the protest zones all over the country but especially and notably in Tienanmen Square, and shot and killed people until the protest effort collapsed.",
"To put it very simply, after Mao died, the economic reforms(free markets and international trade) were so dramatic that it seemed natural that political reform would follow. Students got passionate about challenging the government and wanted opportunities in a democratic political system that would complement the capitalist economic system.\n\nSeemed like a no brainer that the government could be challenged, they were wrong.\n\nThere were slight concessions being offered by CCP moderates(which were huge in the scope of PRC history), but the students weren't satisfied. Moderate leaders were no longer able to keep old-fashioned Maoists under control, and the army was sent in.\n\nThe army was seen very positively at the time, which contributed to the shock."
]
} | [] | [] | [
[],
[]
] |
||
44g3qx | if you saw a picture of a waveform, could you recreate the audio? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/44g3qx/eli5_if_you_saw_a_picture_of_a_waveform_could_you/ | {
"a_id": [
"czpxtmt",
"czpxzmj",
"czq7eg0"
],
"score": [
3,
15,
2
],
"text": [
"There was a point when I could, in a limited way. Not anything specific like speech or complex sounds like that; but for a while I worked producing video, and I could tell a note from looking at the waveform in the oscilloscope. I could also generally tell the instrument that was producing the note. I probably can't anymore, it's been 3 decades.",
"This is actually how a projector reads the sounds of the film.The sound is recorded next to the image on the film, and the projector shines light though the waveform as the film is moving by.\n\nDifferent amounts of lights gets though as the waveform gets wider and narrower. on the other side there is a light sensor, converting the amount of light in to an electric signal that is then sent to a speaker.\n\n_URL_0_",
"Absolutely, you just need a high enough resolution image. In practical terms, when editing speech I can get quite good at recognising the shape of certain words and phrases."
]
} | [] | [] | [
[],
[
"https://youtu.be/En__V0oEJsU?t=6m24s"
],
[]
] |
||
9dyren | why do microscopic images always look cartoonish? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9dyren/eli5_why_do_microscopic_images_always_look/ | {
"a_id": [
"e5kwvnp"
],
"score": [
2
],
"text": [
"Depending on the type of microscope, they are often false color, or use a contrast dye. The shallow depth of field tends to make borders stand out looking more like outlines. There's also just not that much stuff in the field of view compared to what were used to in the chaos of the macro world. So simple lines and high contrast look cartoony."
]
} | [] | [] | [
[]
] |
||
2y2pio | why does being upset mentally cause physical symptoms of sickness? | Like diahorrea, headaches , loss of appetite and body aches etc | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2y2pio/eli5why_does_being_upset_mentally_cause_physical/ | {
"a_id": [
"cp5odx9"
],
"score": [
3
],
"text": [
"Mental upset causes your body to release stress hormone. Prolonged presence of stress hormone triggers shut down of digestive functions which causes the diarrhoea, loss of appetite, inappropriate reaction to certain foods, ect. It also alters brain functions which can cause headaches, brain fog, ect. The immune system also has reduced functioning making you prone to infection, which may result in additional symptoms later on. There's also the effect it has on the heart and muscles, changes in blood pressure, ect. These can cause you to feel dizzy, light headed, chest pain, muscle tightening, muscle soreness, ect.\n\n"
]
} | [] | [] | [
[]
] |
|
3l7y72 | why is inflation not tied to population? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3l7y72/eli5_why_is_inflation_not_tied_to_population/ | {
"a_id": [
"cv3yef8"
],
"score": [
3
],
"text": [
"This is a pretty complex question, as inflation is a pretty in depth topic. I'll try to address it the best I can in a Reddit post.\n\nAt a high level, some inflation is _good_ for an economy, regardless of population. You want goods to slowly get more expensive because that encourages spending and investing over straight saving as well as serves as a buffer against deflation (which is really, really bad). Inflation is also necessary for population growth, as you need an ever increasing monetary supply to support growing populations, else we run into that deflation problem again.\n\nThat all said, inflation levels that are too high are also very bad for the economy, regardless of population growth. You want the number to hover right around 3%ish, as that seems to be the sweet spot where the benefits are greatest and penalties the lowest.\n\nInflation doesn't have much of an impact on inequality, so long as wages increase along with inflation. Even if they don't, the inflation targets are still good for lower income people, as inflation reduces the value of any debts they may have."
]
} | [] | [] | [
[]
] |
|
3wizve | why have global oil prices tanked so dramatically? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3wizve/eli5_why_have_global_oil_prices_tanked_so/ | {
"a_id": [
"cxwjovy",
"cxwvu51"
],
"score": [
5,
2
],
"text": [
"The main reason is a massive increase in oil production. In America, oil production had been decreasing for years. Oil prices had been going up and up. Then in 2013-4, a new technology, called hydraulic fracturing, for extracting oil suddenly took off. It was expensive, but the new high oil price made it worth it.\n\nHuge amounts of money started flooding into setting up hydraulic fracturing oil production in the US. As a result, a huge amount of new oil production came online and flooded the market. US oil demand has been going up for the last couple of years, but the increased production has more than made up for it.\n\nThe market flood has been made worse by countries like Saudi Arabia who depends on high oil prices for income. The government needs the oil money badly, and as the price drops, they need to sell more to make up for the lower price. They have pumping oil at maximum speed in order to try to get as much money in as possible. \n\nFinally, it had been expected that oil consumption in China would be increasing at a lightning speed, and even though more supply of oil came, it would only be a few months or a year before China started using it. However, recent figures from China suggest that their oil consumption is increasing much more slowly, so it will take many years before demand catches up with supply.",
"The US experienced an oil boom a few years ago. Oil prices were around $70-90 a barrel. Only problem was they used fracking. More expensive than traditional oil drilling like Saudi Arabia and the other OPEC countries do. Fracking let's say costs $30 a barrel to operate, while classic drilling costs $10. So US companies were making $40-60 a barrel driving industry. OPEC sales fell, so controlling the market, they increased output flooding the market. Now with the increased supply, oil today is $40 a barrel. Their goal is to bankrupt more expensive US fracking. So now all these US frackers expecting to make $40-60 a barrel are now only profiting $10 a barrel. 25% their previous rate. They grew too fast with the new oil boom expecting prices to still be in the 70-90 range. The other oil nation's goal is to bankrupt these US fracking businesses so that they can raise the prices once they're all out of business. That's how despite being more scarce and in turmoil, oil is in a 8 year low.\ntl-dr; OPEC increases production because they have a lower per barrel cost hoping to drive out more expensive US fracking"
]
} | [] | [] | [
[],
[]
] |
||
61pxrg | when people thought that the earth was the center of the solar system, how did they explain planets moving behind the sun? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/61pxrg/eli5_when_people_thought_that_the_earth_was_the/ | {
"a_id": [
"dfgdtas",
"dfgdv2p",
"dfge2pr",
"dfggavj",
"dfghkel"
],
"score": [
30,
2,
9,
3,
5
],
"text": [
"If I am remembering correctly, the understanding was that the order went something like this:\n\nEarth - > Moon - > Sun - > \"Stars\" (including planets with everything else that's just a bright dot). \n\nSo to the extent they observed the planets moving behind the sun, it made sense since they were behind the sun. ",
"They believed the Sun was very small and was the closest thing to Earth aside from the Moon, so that would seem to explain why planets moved behind the sun.",
"One thing to consider is that only Venus is bright enough to be visible in the daytime, and even then the sun was simply too bright for them to really track the planets moving near it without any fancy filters or IR stuff like we'd have today.\n\nThey had a hard time seeing the discrepancy in their theory",
"The Ptolemaic geo-centric model of planetary motion, developed to explain and predict planetary motion based on a geocentric view of the universe, was very complex, which is why Copernicus' model was so attractive to scientists. Wikipedia has an explanation of the Ptolemaic model.",
"By center if we mean frame of reference no one is actually wrong.\n\n Explaing/predicting motion of planets would be pretty complex. Indian astronomers used epicycles - basically modeling planets as moving in circles around a point which in turn moved around the earth. \n\nFrom the ancients point of view planetary motion was taken as a problem of solving the relative motion - Copernicus showed a more convenient frame of reference. \n\nThere is a whole religious angle which I'm not mentioning here though."
]
} | [] | [] | [
[],
[],
[],
[],
[]
] |
||
28tyoo | why do planes need a billion buttons and switches in the cockpit? | I've been in one of the pilot school simulators before and it seemed like the only important things were radio, lights, landing gear, flaps, engine speeds, tail rudder, and the steering wheel. What do the rest do and why are they important? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/28tyoo/eli5_why_do_planes_need_a_billion_buttons_and/ | {
"a_id": [
"ciegvyo",
"cieh6jd",
"ciei8dg",
"cielpoi",
"ciels9r",
"cien3mm",
"cieo0tw",
"cierayf",
"ciergoo",
"cietcg0",
"cievf7o",
"cif0zkz"
],
"score": [
133,
4,
63,
10,
8,
25,
3,
2,
2,
2,
16,
2
],
"text": [
"When you're in a flying box with upwards of a hundred people as your responsibility, the last thing you want to do is rely on a computer having 100% control over ANYTHING.\n\nThe cockpit has manual controls for damn near (if not all) subsystem onboard. Most switches/buttons probably never need to be flipped, but you want to have absolute control over everything for any sort of \"just in case\" moment, because at 30,000 ft. you don't have any other options if something goes wrong.",
"In more concise words, those are probably the most important things, but there are numerous panels and instruments that monitor things like altitude, weather (being a good pilot requires you to have some basic working knowledge of weather patterns), fuel status, auxiliary systems, flight paths, navigation systems, air conditioning, oxygen, and also very important things like anti ice controls, (get too much ice on the wings and you are well and truly fucked.) The design may be more complex or simplified depending on the manufacturer/aircraft, but for commercial airline jets, you can control essentially every system on the plane from the cockpit.\n\nSource: My dad has been a pilot for 45 years.\n\n",
"An awful lot of those switches you see are circuit breakers as well. Electrical failures and trouble shooting have to be handled while still flying the plane. ",
"One of the best explanations I've ever seen on this topic: _URL_0_\n\n(It's the first answer, so don't worry about registering.)",
"If you ever have the chance, I suggest reading Airframe by Michael Crichton. It will give you a sense of scope for how complicated airplanes are. \n \nAlso, it's a banging book.",
"A & P mechanic here. I apologize in advance if my typing is off as Im on my phone. \n\nSo lets get started. Putting aside all of the essential controls such as main power and distribution, engine control switches (one set for each engine), Flaps, Main landing gear, and lighting youre left with, well....everything else. There's literally so much going on. Each engine, and every aircraft is different..so bare with me..usually has a set of master switches or starter switches, Each engine has its own AC generaator with its own set of switches usually located on the power panel. Each engine has its own hydraulic pump switches and bleed air switches. The fire detection and extinguishing panel has its own set of \"T handles\" as well for each engine. Multiply these switches by the number of engines the aircraft has and you can start to see exactly why the cockpit or \"box office\" for our female crew, has so many switches. Then theres lights. You have Position lights, Anti-collision lights, Landing lights, Formation lights for our military bros, storm lights, Interior lights, eyebrow lights...etc...all with their own switches..Then you have the power distribution panel. Which usually contains all the generator switches, inverter and rectifier switches, DC and AC bus switches and so on. Then you have the bleed air panel which usually has all thr heating and A/C switches along with their manual and Auto mode switches. The fuel section has its own set of switches one for each tank containing all the boost pump switches feed and cross feed switches and anything else it needs. APU control switches...Youve got an Anti-skid control panel various avionics and navigation panels, trim switches, test switches, and circuit breakers out the ass which are mainly used in flight to isolate systems from various busses. NOT troubleshoot in flight. \n\nA lot of people dont realize the amount of systems all working at one time to keep an aircraft in flight safely while monitoring all the flight data. There are MANY systems working together and each system has its own set of switches and redundant back up systems with their own switches. It looks confusing and it can be when youre brand new to the field but once you start to learn systems readily used in an aircraft it all starts to make sense. \n\nEach new aircraft I work on is a new clusterfuck to map out but I always figure it out pretty quick. Its like adding new shit to your cars dash board. Eventually you get so much shit going on that you k ow exactly where everything is and what it does but to some poor sap looking in he has no clue what the hell you got going on in there. ",
"Most of those important things are actually systems, comprised of many many parts and also backup systems. An example, you say radio, but an average army blackhawk has two FM radios, one UHF radio, one VHF radio, one SATCOM radio, one Blue Force Tracker, one HF radio, and an internal communication system. Each of those has a control box (with like....eleven buttons,) a receiver/transmitter, and possibly an amplifier. That's well over a dozen components and we're just on the first thing you mentioned, radio, which is simply being able to talk, try flight controls and navigation. Some of the small single engine planes can be pretty barebones, but the bigger aircraft have a lot of stuff going on and there has to be a switch for everything.",
"Why is more than 1 pilot needed? is it because one flies while the other sleeps in long flights? is only 1 pilot needed in short flights?",
"A lot of the switches have duplicates as well because most systems have backups.",
"Most of those round things you see aren't buttons. They're circuit breakers.\n\nEvery time I show someone the cockpit of my aircraft they ask about \"all the buttons\", but the circuit breakers are right there for pilot access to let me immediatly know if a component shorts out, or so I can isolate and secure equipment during an electrical fire. I don't want to JUST TURN EVERYTHING OFF in an aircraft like you would on the ground.\n\nSource: Im a Helicopter Pilot",
"Former pilot here.\n\nA very large amount of those switches and dials never get touched. Most of them are \"idiot lights\": it's when they're off their normal parameters that you got to look at them.\n\nTo give you an idea, take a look at [the interior of a Cessna 172, one of the most popular small airplanes in the world](_URL_0_).\n\nNow! Here's what the dials do.\n\n* **Mini-dial on the top left:** Suction meter. Many of the airplane's systems rely on an input from the outside air. If this falls outside of ideal parameters, you'll get erroneous readings on several of your instruments.\n\n* **Top left:** Chronometer. Used to get an idea of your actual ground speed. You count the time taken to fly between two landmarks and you compare with your estimate to figure out if you're going faster or slower than expected.\n\nGoing towards the right...\n\n* **Air speed:** keep this in the green zone!\n\n* **Artificial Horizon:** Used to figure out your airplane's posture, especially in low visibility.\n\n* **Altimeter:** Keep that above zero. Whatever you do.\n\n* **VOR-ILS:** This device is able to lock onto a ground beacon and tell you in which direction you are from it. These beacons are essential to \"instrument flying\" in which you navigate the airplane without ever looking outside your window. This one also contains an \"ILS\" package which is meant to assist in landing. All the pilot needs to do is to keep the white cross dead center.\n\nNext row!\n\n* **Upper square dials:** Fuel tank level.\n\n* **Lower square dial:** Battery charge status. One to tell if the battery's charged, the other to tell if the battery is charging.\n\n* **Turn Coordinator:** For coordinated flight. When banking the airplane, the pilot will press the rudder a bit so that when the airplane turns, it turns on its center axis. If he doesn't press the rudder, the airplane will turn around an axis located somewhat above itself, and this is overall less efficient. You also see two angled white lines. By banking such that the aircraft diagram's wing touches one of those lines, it ensures that it will take exactly one minute to do a full 180-degree turn. Often used when you're waiting for your turn to land: air control will tell you to do circles around a spot and you'll use the Turn Coordinator to do that in a predictable fashion.\n\n* **Heading:** Where you're going. Unlike a magnetic compass, the heading indicator reacts to the perceived movement of your airplane.\n\n* **Climb Indicator:** Measures your rate of climb.\n\n* **VOR:** Another VOR! You'll see why later.\n\nBottom row:\n\n* **RPM:** Rounds per minute. This is an extremely important part of small aircraft as a loss of power can signify engine failure.\n\nOn the middle panel are the radios. Each is a combination of standard spoken radio frequency (left) and VOR frequency (right). Aircraft tend to pack two of those, this way a pilot can listen in on two frequencies at once and/or keep one frequency \"saved\" so he doesn't need to work the dial all the time. It's common for pilots to prepare their next frequency in advance and then switch from one radio pack to another. This is why you saw two VOR dials: each is linked to a different radio pack.\n\nBelow the radio pack:\n\n* **NDB:** This is a predecessor to the VOR. Quite simply, the arrow will point directly at a chosen ground beacon! It is a lot less precise however.\n\nRed screen below:\n\n* I think this is the *DME*, the Distance Measuring Equipment. This tells the pilot how far away from a VOR beacon he is, allowing him to better ascertain his position.\n\nBelow that:\n\n* **Transponder:** This is used to make you visible on air control's radar. If that thing's off, they can't see you!\n\nYellow patch on the right:\n\n* **CO2 indicator:** If this patch turns black, this means you have CO2 contamination in the cockpit and should land as quickly as physically possible!!!\n\nWooden-like panel below all that:\n\n* On the left are **circuit breakers**.\n\n* The switches are the various **lights**.\n\n* The black and red levers are the **engine controls**. The pilot will almost always have his hand on the black one, to control the throttle.\n\n* At the far right are the **flaps**, which are used in landing: they allow the aircraft to lower its speed and achieve more control over its descent.\n\n----------------------------------------------------\n\n**Do you REALLY look at all of these?!**\n\nNo. The six big dials above the steering column are the bread and butter of flight. Most everything else is situational and are not looked at nearly as often.\n\n**And what about big aircrafts?**\n\nThe bigger you get, the more stuff you have to control: landing gears, interior lights, various systems located around the passenger area, etc. While the basic control surfaces remain the same, there are tons more circuit breakers and misc. switches to go around. The entire instrument panel is duplicated (unlike my Cessna screenshot which has it only once) and there are oftentimes duplicated per-engine dials.\n\nTake RPM for instance. The Cessna has one engine, so only one set of engine dials. Take a big jetliner, which might have two or even four engines... and that many more engine dials.",
"Let's look at just the things you listed:\n\n > radio, lights, landing gear, flaps, engine speeds, tail rudder, and the steering wheel\n\nNot only are these systems much more complex, than lets say on a car, but you also have redundant parts to these systems in case part or all of the system fails. Plus you have systems that diagnose problems with these systems. Also, when it comes to the critical systems you might have a completely different system that provides the same information but in a completely different way (digital vs analog) so you can identify potential mistaken readings. This can all add up to a lot of buttons, switches, dials and gauges.\n\nThen there are lots of other systems other than what you listed.\n\nHere are some good pictures and descriptions of [the 787 cockpit](_URL_0_)."
]
} | [] | [] | [
[],
[],
[],
[
"http://www.quora.com/Airplanes/What-do-all-the-controls-in-an-airplane-cockpit-do"
],
[],
[],
[],
[],
[],
[],
[
"http://3.bp.blogspot.com/-cuJ9C1x7EI0/TkX8ER45PpI/AAAAAAAAKG8/N-akWc1MOdM/s1600/Cessna+172+Interior+%25285%2529.jpg"
],
[
"http://www.wired.com/2011/10/cockpit-tour-of-all-nippon-airways-boeing-787-dreamliner/?viewall=true"
]
] |
|
3t3k5d | how do illegal immigrants apply for welfare if they dont have any social security card or formal identification? | I hear a lot of talk in the American debates about illegal immigration constantly and how they are using welfare. How is this possible if they dont even have the right credentials to sign up for welfare? I cant even get my new drivers license without several forms of ID. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3t3k5d/eli5_how_do_illegal_immigrants_apply_for_welfare/ | {
"a_id": [
"cx2sgl3",
"cx2suoh",
"cx2tn51",
"cx2uvd7",
"cx32sa7",
"cx396nz"
],
"score": [
15,
2,
5,
6,
3,
2
],
"text": [
"Under circumstances where you are eligible for such a program, there are usually alternatives to a Social Security Number. For example, illegal aliens can legally receive the child tax credit for their dependents, and can file their tax returns using an IRS-provided International Taxpayer Identification Number instead of an SSN. If you are otherwise eligible for a program, most agencies do not require you to provide an SSN or similar documentation if you can prove you do not have them and cannot obtain them.\n\nAs for welfare fraud, illegal aliens who participate in that do it the same way as other people, by making false statements and using false documents. There's a lively market in Social Security cards and birth certificates, which illegal aliens often use without knowing they belong to a real person.\n\nYour driver's license is not a welfare program. Many states try to make it easy to apply for welfare (though others make it hard), because they feel it is important for the poor to have access to these programs, but they make it hard to apply for a driver's license for the first time, because they want to apply extra scrutiny before providing an identification document.",
"Their children are born citizens and can receive benefits. \n\nThey could also qualify for homeless benefits, which require very little in the way of documentation for obvious reasons. For example, they can be verified via \"collateral contact\" which may be a shelter employee or employer, and are not required to disclose where they live, though that would help their case in some situations. Sometimes stuff like schooling and emergency medical care are also thrown under the \"welfare\" umbrella.",
"I would like to know what happens to all the funds collected on behalf of the multiple illegal workers using one SS#. Many years of working in the foodservice industry, whole families using a single SS#. Must be going somewhere. ",
"I'm Australian, so I can't really speak for how the US handles this. But over here, any illegal immigrants wouldn't be able to get anything directly from the government.\nTo receive money from the government you need to provide quite a bit of identification (citizenship, driver license, etc..) and other things like prior tax receipts.",
" > hear a lot of talk in the American debates about illegal immigration constantly and how they are using welfare. How is this possible if they dont even have the right credentials to sign up for welfare?\n\nThe people saying it probably don't know either. They just know that the thought of *anyone* getting welfare riles up conservative voters, when it's illegal immigrants they're *really* angry about it.",
"According to the Mexican Migration Project about 15% of undocumented migrants receive some form of federal assistance and about 50% pay federal taxes. \nState & local programs aside, I don't think the premise of your question is correct. The sort of rhetoric about immigrants and migrants that is popular amongst some presidential primary candidates isn't the most accurate.\n\n*Couldn't get the link to work in text for some reason _URL_0_"
]
} | [] | [] | [
[],
[],
[],
[],
[],
[
"mmp.opr.princeton.edu"
]
] |
|
59j6if | what is the point of throwaways? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/59j6if/eli5_what_is_the_point_of_throwaways/ | {
"a_id": [
"d98ufte"
],
"score": [
3
],
"text": [
"No. If you say something like \"I intentionally ruined my best friend's life\", and then later (or at an earlier time) posted your personal information, people will know. The point of a throwaway is to use ONLY for telling how you ruined your best friend's life, nothing else. That way, you action can't be associated with you."
]
} | [] | [] | [
[]
] |
||
1wjcb4 | with evolution, if human beings are always evolving from one generation to the next, at what point in the future are people no longer human beings? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1wjcb4/with_evolution_if_human_beings_are_always/ | {
"a_id": [
"cf2is0w"
],
"score": [
6
],
"text": [
"By definition they will no longer be homo sapiens when they cannot successful procreate with homo sapiens.\n"
]
} | [] | [] | [
[]
] |
||
54ip2y | what are the differences between different types of missiles/rockets? | I have often hear of Ballistic Missiles, Cruise Missiles, Rockets, and other types of similar weapons. To me, they all represent a weapon that flies threw the air and destroys a target.
What are the differences between these, and other types of similar weapons?
Honestly, I am having difficulty wording this question because I know so little about military weaponry. I am asking this question because whenever I read a story about military conflicts or potential conflicts, I often here these weapon terms but cannot differentiate between them.
Thank you. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/54ip2y/eli5_what_are_the_differences_between_different/ | {
"a_id": [
"d8279zi",
"d828bfc",
"d82dnv2",
"d82hs5a"
],
"score": [
3,
2,
2,
6
],
"text": [
"Rocket vs missile is sort of based on who you are talking to. In general a missile is a guided weapon that can make course corrections as needed. A rocket is aimed at launch and generally can't make course corrections. Although guided rockets do exist.\n\nA ballistic missile follows an arc to the target. Kind of like how you'd throw ball underhanded. \n\nA cruise missile is generally a terrain following weapon. Kind of like how an airplane would be flown to the target. A much more level flight instead of a parabola shaped flight path.\n\n",
"The terms tend to get used interchangeably.\n\nWhen you're talking about weapons generally the difference is guidance. A missile is guided. It flies *to* it's target. A rocket is unguided. It is launched *at* the target. Though unguided missiles and guided rockets exist, so the general rules isn't always true.\n\nBallistic missiles are generally quite large, have a long range, and a relatively large payload. They range from smaller truck-transportable weapons like the [SCUD](_URL_1_) missile to larger, fixed-based weapons like the [Minuteman ICBM](_URL_2_). Ballistic missiles are usually divided into categories based on their range. Short-range (SRBM), medium range (MRBM), and intercontinental (ICBM) are the most common categories you'll hear about. Ballistic missiles are so-called because they follow a [ballistic arc](_URL_0_) as they fly.\n\nCruise missiles are best thought about as an unmanned aircraft. They are launched, fly towards their target much like a jet would, and then either strike the target directly, or release submunitions (small bomblets) or other weapons over the target. Some are pre-programmed with target coordinates, some are actively guided through a radio link with their launch vehicle, and some have onboard systems that can identify targets. Most modern cruise missiles have options to use more than one guidance/targeting system and some of the newest models can network with other missiles and drones to locate targets.",
"A rocket is a means of propulsion in which the fuel system is entirely self contained (all the components necessary for thrust are a part of the rocket).\n\nA missile is a projectile weapon which may or may not be powered by a rocket. (The V1 rocket used by Germany in WW2 was powered by a jet engine).",
"The guided vs unguided rule is mostly true, however - a little more information for you:\n\n[Rockets](_URL_14_): Such as the [Mk66m6 Hydra 70](_URL_19_) are 'cheap', high volume, rapid-fire projectiles for causing general chaos. Modern variants can, indeed, be guided and can be fused to explode on impact, in the air above the target or when it detects that it is near a target. You may also have heard of the [RPG-7](_URL_5_) or the classic [Bazooka](_URL_22_) - both man-portable.\n\n[Air to Ground/Air to Surface Missiles](_URL_7_): Such as the [Brimstone II](_URL_18_) are generally assigned a target - like a position on the surface, a specific heat signature on the ground, a laser-designated target, etc. and then fired from an aircraft. That could be an attack helo, a CAS Aircraft like the [A-10 Thunderbolt II](_URL_31_), or most other strike aircraft. These are also the kind of missiles you will hear about when people say 'Drone Strike'. The [MQ-9 Reaper](_URL_2_) carries 4 [AGM-114 Hellfire](_URL_25_) air to ground missiles. It also carries a bunch of guided bombs (we'll get to those) and has been tested with the Brimstone missile system.\n\n[Air to Air Missile](_URL_37_): Such as the well known [AIM-9 Sidewinder](_URL_0_). These do what they say on the tin - how they do it, however, varies massively. Generally, you somehow target or cause to be targeted a (hopefully) enemy aircraft then set your missile loose. Due to the rapid pace of anti-missile technology (beyond our scope here), there is a rapid turn-over of AIM (Air Intercept Missile) variants. Some use heat (IR guided), other onboard radar (active), some ground or aircraft-based radar (semi-active) or passively detect enemy radar and radar jamming signals (passive, or home-on-jam). Yet more, such as the [Python 5](_URL_8_) can use target visual identification to track their target, and can acquire and attack their target *after launch*. Anti-aircraft missiles typically make their kills by firing a cone of shrapnel at the target, shredding vital equipment, control surfaces and possibly people like a giant rocket-propelled, guided shotgun shell.\n\n[Surface to Air/Ground to Air Missiles](_URL_29_): Such as the short range (8km), man-portable [Stinger](_URL_6_) or the huge (5.8m, 700kg), long range (160km) ([Patriot missile system](_URL_36_). These are very much the same as the air-to-air variety but come with a collection of ways to get the missiles into the fight. Without the benefit of the aircraft doing the donkey work of getting the missile up to altitude, they often have booster motors or are generally much larger than their aircraft mounted counterparts. Some, such as the Patriot (again) can be used to protect against ballistic and cruise missiles.\n\n['Cruise' Missiles](_URL_38_): Such as the well known [BGM-109 Tomahawk](_URL_20_), not so well known [Storm Shadow](_URL_23_) or the often forgotten [V1 Flying Bomb](_URL_27_) from WWII. These fellows are basically small (or not so small), incredibly fast aircraft consisting of an airframe, a guidance computer, all the stuff you need to make it fly and generally a pretty hefty payload - in some cases, even nuclear (the Tomahawk TLAM-N for example). Starting with the V1, which was pretty dumb by modern standards (but astonishing by the standards of the day, eventually hitting a target area 7 miles in diameter with a calculated, powered dive) and moving on to modern stealth cruise missiles, which skim inches above the terrain, and even down city streets to sneak up on their targets. Typically GPS/GLOSNASS guided, and sometimes able to make decisions about the final attack vector on approach, because of the big plus that cruise missiles bring - *range*. Ranges can be 190 miles, up to well over 1000 miles. This stand-off capability lets you launch low-risk strikes from far, far away - often on or under the sea. Yes, they can also be launched [from submarines](_URL_9_).\n\n['Ballistic' Missiles](_URL_30_): These are often called 'nuclear missiles', though they don't have to be. Examples are the US/UK nuclear armed [UGM-133 Trident II](_URL_33_) submarine-launched ballistic missile (SLBM), the short range but still scary Soviet-era [SCUD](_URL_12_) which can have anything from a standard high explosive tip to chemical and nuclear warheads. They are called 'ballistic' missiles because they are (generally - there are always exceptions) only powered during their ascent. Once they reach the apex of their trajectory, the motors are spent and the rest of the trip is done under gravity. Control surfaces such as fins are used to target the missile, but essentially its reaches the top and turns into a dangerous sling stone. The technical aspects of the warheads vary, with some very clever ways to deliver maximum death to maximum people - we won't go into it, it's all very depressing. It must be noted that *ballistic missiles are in use in the world today* in Syria, for example. Modern defence systems are getting much better at shooting them down, but those clever ways to deliver death I just mentioned... well, they're always working to make the place a [little worse](_URL_1_).\n\n[Unguided/Dumb/Gravity Bombs](_URL_28_): These are the various unguided, unpowered, low precision explosives dropped from aircraft since we realised [we could](_URL_32_). 'Modern' variants, such as the [Mark 82](_URL_35_) are usually upgraded to be 'smart weapons' by strapping a seeker on the front and some control fins on the back. This significantly increases the effectiveness of the weapons.\n\n[Guided/Smart Bombs](_URL_21_): Around since the end of World War II, guided bombs allow smaller explosive charges to do more precision damage. These are still unpowered, relying on the height and speed of their launching aircraft to impart momentum for their flight systems. Modern examples include the [GBU-39 Small Diameter Bomb](_URL_11_) and the [JDAM](_URL_16_) (a Mark 82 unguided bomb with fancy bits stuck on). Some weapons also cheekily cross the divide, such as the [AGM-123 Skipper II](_URL_4_) which was an unguided bomb platform with two rocket motors taped to its ass to give it a little extra range and earning it the AGM designator - they call it 'rocket assisted'.\n\n[Artillery](_URL_24_): This is your classic 'big gun' and covers everything from the cannon on a tank, through to a cannon on a pirate ship in days gone buy. The general principle is - load a shell that will do the thing you want (blow up, fragment, make smoke, lay a mine, seek its target, etc.), stick a known quantity of explosive behind it, seal it in a tube and light the lot on fire. With a bit of trigonometry (ok, a lot of trigonometry when you consider these things can fire upwards of 40km such that the rotation of the earth becomes a factor). Your current fancy shells can be satellite-guided like the [M982 Excalibur](_URL_34_), laser guided like the [M712 Copperhead](_URL_26_), or classically unguided like [most other shells](_URL_17_).\n\n[Mortars](_URL_13_): A subset of artillery, often man-portable to provide rapidly moving offensives with indirect fire support, or to cover a withdrawal with a staggered fire-move-fire. They can drop everything from your common or garden explosive round, to flares, smoke screens and IR Illuminators (invisible flares). From the wiki article - \"*A mortar is a device that fires projectiles at low velocities and short ranges. The mortar has traditionally been used as a weapon to propel explosive mortar bombs in high-arcing ballistic trajectories.*\" What that means is, you drop a bomb down a short, angled tube and it detonates a propulsion charge of known strength when it hits the bottom (other launching methodologies are available, see arms suppliers for details). This lets you accurately calculate the landing point of the mortar bomb, given environmental conditions such as wind, humidity, temperature, etc. Once the bomb leaves the mortar, there usually isn't any further propulsion - again, modern weapons are complex beasts and super fancy mortar shells exist, like the [XM395 PGMM](_URL_3_).\n\nThere is more to see, from [FAE](_URL_15_) to [HVMs](_URL_10_). It is a fascinating journey into engineering in an extreme environment and man's creativity when it comes to harming his or her fellow man.\n\nTL;DR: **boom**"
]
} | [] | [] | [
[],
[
"http://imgur.com/a/hyFHl",
"http://imgur.com/a/9DlHM",
"http://imgur.com/a/HjJj9"
],
[],
[
"https://en.wikipedia.org/wiki/AIM-9_Sidewinder",
"https://en.wikipedia.org/wiki/Multiple_independently_targetable_reentry_vehicle",
"https://en.wikipedia.org/wiki/General_Atomics_MQ-9_Reaper",
"https://en.wikipedia.org/wiki/XM395_Precision_Guided_Mortar_Munition",
"https://en.wikipedia.org/wiki/AGM-123_Skipper_II",
"https://en.wikipedia.org/wiki/RPG-7",
"https://en.wikipedia.org/wiki/FIM-92_Stinger",
"https://en.wikipedia.org/wiki/Air-to-surface_missile",
"https://en.wikipedia.org/wiki/Python_%28missile%29#Python-5",
"https://www.youtube.com/watch?v=FwV-JucQktQ",
"https://en.wikipedia.org/wiki/Starstreak",
"https://en.wikipedia.org/wiki/Small_Diameter_Bomb",
"https://en.wikipedia.org/wiki/Scud",
"https://en.wikipedia.org/wiki/Mortar_%28weapon%29",
"https://en.wikipedia.org/wiki/Rocket_%28weapon%29",
"https://en.wikipedia.org/wiki/Thermobaric_weapon",
"https://en.wikipedia.org/wiki/Joint_Direct_Attack_Munition",
"https://en.wikipedia.org/wiki/Shell_%28projectile%29",
"https://en.wikipedia.org/wiki/Brimstone_%28missile%29",
"https://en.wikipedia.org/wiki/Hydra_70",
"https://en.wikipedia.org/wiki/Tomahawk_%28missile%29",
"https://en.wikipedia.org/wiki/Guided_bomb",
"https://en.wikipedia.org/wiki/Bazooka",
"https://en.wikipedia.org/wiki/Storm_Shadow",
"https://en.wikipedia.org/wiki/Artillery",
"https://en.wikipedia.org/wiki/AGM-114_Hellfire",
"https://en.wikipedia.org/wiki/M712_Copperhead",
"https://en.wikipedia.org/wiki/V-1_flying_bomb",
"https://en.wikipedia.org/wiki/Unguided_bomb",
"https://en.wikipedia.org/wiki/Surface-to-air_missile",
"https://en.wikipedia.org/wiki/Ballistic_missile",
"https://en.wikipedia.org/wiki/Fairchild_Republic_A-10_Thunderbolt_II",
"https://commons.wikimedia.org/wiki/File:SSZ_class_blimp_dropping_bomb_WWI_IWM_Q_67695.jpg",
"https://en.wikipedia.org/wiki/UGM-133_Trident_II",
"https://en.wikipedia.org/wiki/M982_Excalibur",
"https://en.wikipedia.org/wiki/Mark_82_bomb",
"https://en.wikipedia.org/wiki/MIM-104_Patriot",
"https://en.wikipedia.org/wiki/Air-to-air_missile",
"https://en.wikipedia.org/wiki/Cruise_missile"
]
] |
|
7sp33x | how would the billionaires of the world "end poverty" ? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7sp33x/eli5_how_would_the_billionaires_of_the_world_end/ | {
"a_id": [
"dt6eo2r",
"dt6f08b"
],
"score": [
2,
2
],
"text": [
"I think allot of the money would go towards building infrastructure so that people can support themselves, it definitely wouldn't be a over the night type of thing and a good amount of work will end up in failure but with enough money and time it would surely reduce poverty and hunger world wide but not without consequences. Charities or individuals who do donate a good percentage of the money and resources are stolen especially in third world countries I think what would help end hunger is using the money to expand control over unstable regions so that people can live relatively safely and begin to build a functioning society ",
"It's not enough to end global poverty forever, it's enough to give everyone $60.\n\nWhat is would be enough to do though, is radically upgrade the infrastructure in a few of the poorest regions of the world. Over many years of spending that income you could upgrade a lot.\n\nOf course there are massive logistical and geopolitical issues first, many of these areas are unstable and work can't be completed or even initiated peacefully.\n\nEven if you could confiscate that wealth, the project would be enormously difficult and occasionally violent."
]
} | [] | [] | [
[],
[]
] |
||
1ebpq1 | regular expressions in programming | Really have no idea where to even begin with these. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ebpq1/eli5_regular_expressions_in_programming/ | {
"a_id": [
"c9yom6t"
],
"score": [
3
],
"text": [
"Regular expressions are patterns that a computer can understand and compare with a given piece of text or numbers.\n\nThey are helpful when you want to make sure a text matches a specific pattern. For example to validate email address or credit card number and things like that.\n\nThey can also be used in the same way, to extract some parts of a text. For example, maybe you have a paragraph and you want to extract all the words in that paragraph that start with 'A'.\n\nComputers can process regular expressions very fast.\n\nIn regular expressions there are different patterns and each one means a specific thing that the computer knows in advance.\n\nSo let's have a real example.\n\nSo imagine I have a list of thousands of reddit users, and I want to find those usernames that start with 'G' and end in 'o'.\n\nIn this case I would write a regular expression like this,\n\n > G.*o\n\nlook at that pattern, it starts with G, then a dot, then an asterisk, and ends with o.\n\nTo the computer the dot means 'any character' and the asterisk sign means to 'it may or may not be there, or there may be many'.\n\nNow the computer reads the pattern once and turns it (or 'compiles' it) into something that it can run repeatedly and very fast. So it doesn't need to read and understand that pattern many times.\n\nNow if you test 'Great' against that regular expression, the computer says, oh there's a 'G', after 'G' I might see more characters, or there may be an 'o'.\n\nOh there is 'r', 'e', 'a', and 't'. Ok, but I know it should end in 'o'. So this doesn't match.\n\nIf you try it with 'GFandango', it says ok, there's a 'G' and 'F', 'a', 'n', 'd', 'a', 'n', 'g' and finally 'o'. This matches the pattern I was expecting."
]
} | [] | [] | [
[]
] |
|
74py7b | how do programmers incentivize ais | I often see it stated with little explanation in articles about AI research that programmers use incentives to get Artificial Intelligences to do certain tasks. They never say what the incentive is or how it works.
How exactly does one go about giving an AI an incentive and what would that incentive be? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/74py7b/eli5_how_do_programmers_incentivize_ais/ | {
"a_id": [
"do07wr2",
"do07wtu",
"do07z7k",
"do0aysq"
],
"score": [
5,
11,
2,
2
],
"text": [
"Incentives are basically what the AI wants. It’s usually expressed as a number and the AI is just finding ways to maximize(or minimize) that number. Let’s say you are making an AI to play Super Mario Brothers. The incentive would be the level count. You can also have several incentives that have different weights. So after maximizing the level count, you might want to maximize the score, or remaining lives, or how far to the right you got on a certain level. Level count is the most important, so moving to the next level might be worth 100 points, and the other things are worth 10 or 20, but that’s the idea. One of the complex parts of AI is figuring out how to set these incentives so that the AI does exactly what you want. ",
"Incentive is a misleading word. It's just a weight.\n\nLet's say it can do action A, or action B 50/50. If it picks right, you up the score +5, if wrong, -5.\n\nSo if an answer should be A, and the AI picks A, it becomes 55/45, with a stronger weight towards A being the way to do things.\n\nIt's not an actual consciousness, so it's not incentivizing like a person. it's just math that reweighs things if it gives the correct output.\n\nHere's some previous posts on the topic:\n\n_URL_0_",
"You give it a function that produces a value, and you ask it to maximize or minimize that value.\n\nKind of dumb example since it's solvable in other ways, but maybe you're trying to get AI to find you the fastest driving directions between points A and B, with a potential stop off at point C. You give it a way to calculate how long any set of driving choices would take (e.g. a way to plug in: take I-405 south to I90, then east to I-5, then south to US 101, and out of that get \"2.5 hours\"), and then you ask it to minimize that value. That is its \"incentive\".",
"It is kind of like reddit karma, it is all just numbers.\n\nIf you had an AI trying to learn tic-tac-toe, to pick the first move, you would do the programming equivalent of putting 90 marbles in a bag, 10 each of 9 different colors, corresponding to each starting square. You draw one, make that move, and if you win, you **incentivize** the AI by adding a marble of that color, and remove one if you lose. The next game, it is a little more likely to make the best move, and eventually all the marbles will correspond to good starting moves."
]
} | [] | [] | [
[],
[
"https://www.reddit.com/r/explainlikeimfive/search?q=ai+reward&restrict_sr=on"
],
[],
[]
] |
|
zn7cc | what are the rules for craps? (the dice game) | I've watched games of craps go on and the rules are still foreign to me. How do you play? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/zn7cc/what_are_the_rules_for_craps_the_dice_game/ | {
"a_id": [
"c6631ta"
],
"score": [
2
],
"text": [
"The basic rules are this: \n\nThe player rolls the dice - on the first roll if he or she gets a 7 or 11, it's a winner. 2, 3 or 12, it's a loser. Anything else becomes the \"point\". If the game goes beyond the first roll (that means if a point value is set), the player's goal is to roll the point again before rolling a 7 (and no longer needs to worry about 2, 3, or 12).\n\nGamblers around the table can either bet with the player (\"Pass\") or bet against the player (\"Don't Pass\"), as well a number of side bets (such as betting a 6 will be rolled before a 7). "
]
} | [] | [] | [
[]
] |
|
8e3vrt | what exactly happens when (in movies) the police trace a call and why can't they do it if the call is less than a minute long? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8e3vrt/eli5_what_exactly_happens_when_in_movies_the/ | {
"a_id": [
"dxs5vt3",
"dxs5w4u",
"dxs5wi8",
"dxs5z1b",
"dxs6sn7"
],
"score": [
9,
2,
5,
3,
2
],
"text": [
"It's just a movie plot device. The phone carrier knows immediately where the call originated from. The police would get a warrant and the phone company would hand over the information. \n\nWith cell phones, they would triangulate the call using 3 or more cell towers. Again, it is immediately available as soon as the phone makes contact with the towers. ",
"That's a great question and I've wondered it myself. I'm not an expert on the subject but I have a hypothesis. It probably takes seconds to trace a call now where as it took longer when analog and hybrid technologies were immature. So Hollywood probably adds this in films only to create suspense. Again, just an uneducated assumption. ",
"It's instantenous in the digital era. All the data related to your call is stored, so even if you hang up, the police can still request the operator for the location of the call. Though it's possible that they can't get an exact location for your mobile, especially if it's turned off. Instead, they might only get the list of connection towers the phone was last connected to.\n\nBefore being automated digitally, mechanic and electromechanic [telephone exchanges](_URL_0_) needed a bit of manual effort to pinpoint the location of a caller. 1 minute wouldn't have been enough for it far as I can tell. Probably it'd been more like 15 minutes in the least.",
"The tracing the call as seen in movies is fake. The need to keep them on the line for a certain amount of time is just a plot device used to add tension to the scene. So the easiest answer is... In movies the ot sometimes require a phone trace. In real life this is a fairly quick process and unexciting and would result in a glance at a screen and a \"he's at the payphone on 5th.\" So by having an arbitrary time for the trace to work tension is added to the moment as it's suppose to leave the audience wondering if they are going to get the trace or not. (Spoiler: they don't) ",
"If the movie is set more than about 30 or 40 years ago, it's possible the call was put through manually by operators plugging wires into sockets. It would likely take several minutes for all the operators concerned to figure out exactly where the call was coming from: each would have to work out which wire was carrying the call and see which socket it was plugged into, which would tell them which switching station was next along the line.\n\nBut if the movie is set in the days of digital switching, tracing the call is pretty much instantaneous. Of course they wouldn't rely on caller ID (because that can easily be spoofed or blocked), but the carrier always knows exactly where the call is placed.\n\nSo what's happening when the good guy is desperately trying to keep the bad guy talking, but the bad guy hangs up after 59 seconds and the FBI guy in the background shakes his head apologetically is just a way for the scriptwriters to inject some suspense. In the real world, the location of the bad guy would immediately be revealed and there wouldn't be much of a movie.\n\nThese days there are better and more realistic ways of doing this. Have the bad guy use a cellphone while driving somewhere: although the authorities can triangulate his position using signal strengths from different cell towers, he'll be somewhere else by the time they get there. Or have him use an internet service like Skype but through a VPN, making it not actually impossible but really hard to trace the call."
]
} | [] | [] | [
[],
[],
[
"https://en.wikipedia.org/wiki/Telephone_exchange#History"
],
[],
[]
] |
||
whkco | what is supposed to happen astronomically on december 21,2012? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/whkco/eli5_what_is_supposed_to_happen_astronomically_on/ | {
"a_id": [
"c5ddajs",
"c5ddz51"
],
"score": [
13,
6
],
"text": [
"NOTHING\n\nThe Mayans were going to introduce a new calendar. Full stop. However, they did not survive long enough to need one, so their current calendar just sort of. . . stops. So then white people interpreted this as meaning that the world will stop.",
"Neil deGrasse Tyson explains the whole dec 21 2012 thing here: < _URL_0_;"
]
} | [] | [] | [
[],
[
"http://www.youtube.com/watch?v=9ldflrUD4qQ>"
]
] |
||
jwbr3 | hiv, aids and how are they related to each other? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/jwbr3/eli5_hiv_aids_and_how_are_they_related_to_each/ | {
"a_id": [
"c2fmskk",
"c2frvr2",
"c2fmskk",
"c2frvr2"
],
"score": [
17,
3,
17,
3
],
"text": [
"HIV is a bug that causes AIDS. AIDS is a sickness where the bits of your blood that hunt down other sicknesses stop working. Those bits are your T cells. HIV can sneak into T-cells and take them over, so instead of hunting down sickness, they make more HIV. When there is enough HIV, then many sicknesses can attack you all at once, and that is what kills you. ",
"HIV is the virus. Human Immunodeficiency Virus.\n\nAIDS is an eventual symptom of a runaway HIV infection. Auto-Immune Deficiency Syndrome.\n\nHIV is the virus. AIDS is when you've got no T cells left to detect infections of any kind _because the HIV virus killed them all_",
"HIV is a bug that causes AIDS. AIDS is a sickness where the bits of your blood that hunt down other sicknesses stop working. Those bits are your T cells. HIV can sneak into T-cells and take them over, so instead of hunting down sickness, they make more HIV. When there is enough HIV, then many sicknesses can attack you all at once, and that is what kills you. ",
"HIV is the virus. Human Immunodeficiency Virus.\n\nAIDS is an eventual symptom of a runaway HIV infection. Auto-Immune Deficiency Syndrome.\n\nHIV is the virus. AIDS is when you've got no T cells left to detect infections of any kind _because the HIV virus killed them all_"
]
} | [] | [] | [
[],
[],
[],
[]
] |
||
5orrvu | tesla released all its patent on their car in 2014 so that anyone can use them. why isn't there any other car co. using them atm? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5orrvu/eli5tesla_released_all_its_patent_on_their_car_in/ | {
"a_id": [
"dclj87h",
"dclmtg7",
"dclsvgf"
],
"score": [
7,
5,
2
],
"text": [
"There is no way to know they aren't. There are a lot of patents and licensing that you would have no way to check on who is using what and How.\n\nAlso using a Patent doesn't mean it will look like Tesla, that is a different thing.",
"Any number of manufacturers easily could be using various parts and concepts invented under a Tesla patent and you'd never know it. \n\nAs far as you know the latest Ford Hybrid is using the battery charging systems of a Tesla, and Ford-Original everything else. Nobody's told you because the particular design of the alternator isn't exactly flashy in a banner ad or sales pitch. Nor is admitting that another company does something better than you. \n\nIf you're wondering why nobody has taken ALL the Tesla patents and made a clone, that's just business. Tesla is already having trouble finding markets for their vehicles. Even if you skip the most of the engineering, as a new manufacturer you'd have to still pass all the regulations and safety standards and figure out exactly how to buy/make the exact parts required for the whole car. THEN you could START marketing your new car, and MAYBE find some buyers. \n\nThis represents billions of investment to make a vehicle that would now be 5-10 years out of date (depending on how long it took you to solve the startup problems), and still have a tough time selling against a cheaper, newer, and arguably better standard transmission vehicle. \n\nAnd consumers expect you to repeat the entire operation within a calendar year to produce the 2020 Edison (that they still won't buy). ",
"If memory serves right, a few companies are using their batteries which means they are probably also using charging technology from Tesla. "
]
} | [] | [] | [
[],
[],
[]
] |
||
cscz2f | what changes in how the engine works when switching between different driving modes like eco, sport, etc.? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cscz2f/eli5_what_changes_in_how_the_engine_works_when/ | {
"a_id": [
"exe22j2",
"exe3p65"
],
"score": [
3,
3
],
"text": [
"Nothing much really, between normal and sport(+) the only difference is that your car will shift later up open the exhaust valve to make more noise(if you have a sport exhaust) stiffen up the suspension. You don’t habe over all more power or something and everyone who says that is an idiot, you just get the power sooner and the car feels mire aggressive.",
"Engine mapping is the answer. Engine mapping tells the engine:\n\n\"if the driver is using X% throttle, give him Y% power\"\n\nNow, you may think that pushing the throttle to 30% will give you 30% power, but many times this is not the case.\n\nIn normal driving mode, 30% throttle may equal 25% power, 70% throttle equals 80% power and so on. (I'm just making the numbers up)\n\nIf you switch to sport, at 30% throttle you may get 40% power and at 70% throttle you may get 90% power.\n\nEssentially, the same throttle input results in more power, which can appear to make the car more powerful, but the car does not actually produce more power\n\n\nHere is an excellent video on the topic. Also, keep in mind I wildly simplified it, as lot of other variables are involved, not just throttle input (rpm are also important, for example) _URL_0_"
]
} | [] | [] | [
[],
[
"https://youtu.be/1cr4uIzkD0k"
]
] |
||
83oedp | why is fusion considered the holy grail of energy? | I have a degree in engineering and read a lot of science material, and my own reading has shown:
"The power output of the core of the Sun is about 276.5 watts per cubic metre — that's almost three of the old 100W light bulbs. On a power/volume basis, it's a lot less than your body emits (about 100 W) and around the same as a compost pile."
Basically the only reason the Sun yields so much energy is that it is so staggeringly large.
So, that being said, what is the use in creating a reactor that - albeit will generate a net positive power - will only output such a piddling small amount?
I feel we are wasting millions (likely billions by now) on this. Is there some basic conceptual scale up that I am not aware of?
| explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/83oedp/eli5_why_is_fusion_considered_the_holy_grail_of/ | {
"a_id": [
"dvjbxpf",
"dvjc991",
"dvjds9u",
"dvjef0y"
],
"score": [
22,
9,
5,
3
],
"text": [
" > So, that being said, what is the use in creating a reactor that - albeit will generate a net positive power - will only output such a piddling small amount?\n\nThe fusion output of the sun per given volume doesn't really apply to how it would be performed in a reactor as our designs aren't reliant on what will naturally occur. Consider the difference between a fission bomb and a fusion bomb, the fusion bomb has a far greater output. A practical reactor will be generating far more energy per cubic meter than the Sun does.\n\nWhile fission of uranium releases about 17 times the energy of deuterium and tritium fusion, the key difference is the availability of the fuel. There is enough deuterium in a gallon of sea water to produce an equivalent energy output of about 300 gallons of gasoline. Instead of refining trace isotopes of an already rare mineral into fuel we can just essentially dump water into such a reactor and create huge amounts of energy; that we need 17 times more water than uranium isn't really a problem.\n\nEdit: Consider that U-235 has a natural abundance of 0.72% and there is about 40 trillion tons of uranium on Earth. That means there is conceptually about 288 billion tons of U-235 on Earth.\n\nOn the other hand deuterium has a natural abundance of about 0.015% and there is about 1.36 million trillion tons of water on Earth. That means there is conceptually 204 trillion tons of deuterium on Earth.\n\nThis means fusion fuel is approximately 708.3 times more commonly available than fission fuel. Oh, and the waste products are far less hazardous.",
"The power density of a fusion reactor is not necessarily the same as the power density of the sun.\n\nBut anyway unlike fossil fuels or fission reactors currently used for power generation, the fuel for fusion reactors on Earth is essentially unlimited.\n\nFusion is a nuclear reaction, so the energies involved with the reactions are typically millions of times higher than those of chemical reactions, like combustion.\n\nPer reaction, the fission reactions used for power generation actually releases much more than the typical fusion reactions. But both fission and fusion are millions of times better than chemical reactions in energy released per reaction.\n\nFusion is not a waste at all. It will be a major achievement for the human race.",
" > So, that being said, what is the use in creating a reactor that - albeit will generate a net positive power - will only output such a piddling small amount?\n\nBecause we're not building a sun.\n\nJET, an already build fusion reactor, reached 16 MW of power in 1997, with a plasma volume of 100 cubuc meter.\n\nSo, that's roughly 160 000 W/m^3. Bigger fusion reactors go even higher.\n\n",
"I don't know your exact reasoning, but it looks like you used to total volume of the sun in your calculations. Definitely not all of the sun is actively participating in the fusion. Otherwise the sun would burst in a gigantic explosion. It's a slow chain reaction that slowly burns up the entire sun over the next 5 billion years. \n\nIf we assume all of the sun's 1.4 * 10^(18) km³ burn up evenly over the next 5 billion years (or 1.6 * 10^(17) seconds), that's only 10 km³ (or 10^(9) m³) each second. With a luminosity of 3.8 * 10^(26)W, that's 3.8 * 10^(16) W per cubic metre, wich is quite fenomenal. "
]
} | [] | [] | [
[],
[],
[],
[]
] |
Subsets and Splits
No saved queries yet
Save your SQL queries to embed, download, and access them later. Queries will appear here once saved.