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 |
|---|---|---|---|---|---|---|---|---|---|
alekrb | almonds trees and alike 'use' a lot of water, where does all that water go? | This is in reference to a recent TIL post saying how much water almonds use to produce. Don't trees filter out water and cause a microclimate which in turn makes it rain more? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/alekrb/eli5_almonds_trees_and_alike_use_a_lot_of_water/ | {
"a_id": [
"efde3jg",
"efdxzop"
],
"score": [
6,
4
],
"text": [
"It goes away quite quickly: they run it up to their leaves, and it evaporates from there. This in turn pulls more water up, and so it continues.",
"most water consumed by plants is evaporated from the leaves (and stem, when they're young) to accomplish some essential work, like the absorption of nutrients (roots sucks water and solutes, in thanks to the negative pressure from evaporation at the top, like sucking from a straw) and thermoregulation (evaporation chills the leaves, a bit like sweating)\n\n\na minor amount is photochemically broken (with sunlight) to extract electrons (a form of usable energy) from it, creating oxygen gas as \"waste\" and proton gradient (another form of energy)."
]
} | [] | [] | [
[],
[]
] |
|
2d7pl1 | how do people tame predators such as tiger or lions? | Do they have to raise them from a young age? How would you know that they don't look at you as food? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2d7pl1/eli5how_do_people_tame_predators_such_as_tiger_or/ | {
"a_id": [
"cjmwd56",
"cjmxqku"
],
"score": [
3,
2
],
"text": [
"Raising them from birth helps. If you feed something and give it enough food and space and entertainment, it won't be as inclined to kill you. Although they're tame, not domesticated, so they could snap at any moment.",
"It depends largely upon the species you're training, understanding their instincts, and how animals communicate. In order to train a predator, you have to earn their trust and provide for their needs.\n\nIf you become a source of food, you're far less likely to become a food source. You also have to learn how to be confident and fearless around them. Raising some species from a young age does help -- lions and tigers and bears, oh my, for example. (Here's a great [example](_URL_0_) of that.)\n\nAnd, of course, there are many, many examples of cross-species relationships that would seem to defy conventions -- dogs and cats, dogs and elephants, cats and owls, rabbits and sheep, and on and on. \n\nThink of the primary example of predators that have become a part of human life. Dogs started out as wolves, and wolves are predators who'd just as soon eat us. Same thing with cats. By becoming partners with them, we have extinguished their instincts to eat us. Same thing with tigers and lions. Or any other animal."
]
} | [] | [] | [
[],
[
"https://www.youtube.com/watch?v=ms-piPxEzbk"
]
] |
|
f0jffa | if you’re short sighted, are you able to see something clearly in a mirror that is close to you showing a reflection of something that is further away? or is it still not readable even in the mirror? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/f0jffa/eli5_if_youre_short_sighted_are_you_able_to_see/ | {
"a_id": [
"fguh2oj"
],
"score": [
2
],
"text": [
"Looking into a mirror or directly at this far away object, the light from the object has to travel such a distance any way you look at it, so the object would still not be readable even in the mirror."
]
} | [] | [] | [
[]
] |
||
b8pri1 | is a "meal-in-a-pill" theoretically possible? if so, what are the current limitations in developing it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b8pri1/eli5_is_a_mealinapill_theoretically_possible_if/ | {
"a_id": [
"ejzcnzc"
],
"score": [
4
],
"text": [
"So we've got ones that have all the vitamins and minerals already, that part is down.\n\nThe issue would be shoving all the calories in there, in a way your body could digest them. That part is a lot harder. There is going to be a lot more mass to the pill suddenly trying to fit 2000 calories into it (though odds are you'd get like 4-5 pills with 400-500 calories each throughout the day). That isn't even thinking about fitting different macros into the pill. You can't survive on carbs alone, you need things like amino acids ect.\n\nBut the single biggest barrier to this ever happening is demand. People fucking LOVE food. We love it to the point we often eat ourselves to death when there is lots of it around. We developed holidays and celebrations around food. We developed entire industries around food.\n\nWe love to eat. No one will want to make something that removes eating. We are more likely to see an anti-calorie pill to let us eat more than a calorie pill that makes us eat less. we kind of already have anti-calorie pills but they'll give you the shits something wicked."
]
} | [] | [] | [
[]
] |
||
ebhbd3 | what is the point of having a separate police force? why not just have the army do the policing? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ebhbd3/elif_what_is_the_point_of_having_a_separate/ | {
"a_id": [
"fb4qm84",
"fb4qqos",
"fb4r2vp"
],
"score": [
5,
3,
3
],
"text": [
"The army is trained to kill enemies. The police is trained to keep the peace. It's not the same training at all, having the army do the policing is a recipe for an authoritative government.",
"The military is trained to a force of war capacity. That's excessive for most checkpoints and responding to disputes. Civilian police forces are trained in law enforcement for each state. The military is one standard. Not to mention it is better to scale up for a call in terms of force. Not a good idea to start at the \"time to blow the door open and stack on this house\" policy.",
"In addition to what's been mentioned, you need to be able to deploy the army internationally. What would happen if everytime you sent the army elsewhere, you lost your law enforcement capability at home?\n\nYou'd need a dedicated force which stayed home to keep the peace, and once you have that, why not specialize them into a police force rather than using line infantry."
]
} | [] | [] | [
[],
[],
[]
] |
||
2izunf | how does the information travel through cords to make sound on speakers? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2izunf/eli5_how_does_the_information_travel_through/ | {
"a_id": [
"cl717vw"
],
"score": [
10
],
"text": [
"As electrical voltages and currents. If you put a 1 kHz AC current (current that swap directions 1000 times a second) on the wire, it causes the speaker to move at 1 kHz, which causes the air to move at 1 kHz, which makes you hear a 1 kHz tone. To play more complex sounds, you just put a more complex electrical current on the wire that matches the shape of the sound. "
]
} | [] | [] | [
[]
] |
||
1cwu6f | why does built-in navigation cost so much more? | I'm looking at cars and it looks like getting GPS navigation included costs abut $1000-$2000 extra. But I can buy a Tom Tom, Garmin etc. for ~$100.
Is this just about profit-seeking by the car manufacturer? Or is there something different about the GPS that's built into the car? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1cwu6f/eli5_why_does_builtin_navigation_cost_so_much_more/ | {
"a_id": [
"c9l042i"
],
"score": [
2
],
"text": [
"Because they can. It's not exactly rare that the official accessories and addons costs more than 3rd party alternatives that often are better as well. The reason for why it works out for them is that lots of people simply don't bother to look for alternatives."
]
} | [] | [] | [
[]
] |
|
3c456x | what is the white stuff (i assume it's ice) that i always see falling off of space shuttles at take off and what does it do? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3c456x/eli5_what_is_the_white_stuff_i_assume_its_ice/ | {
"a_id": [
"css35tt",
"css3kg4",
"css46gh",
"css6dxi",
"css9wop",
"cssac7c",
"cssatt8",
"cssb9nc",
"cssjl6z",
"cssks75",
"cssnp24",
"cssnxan"
],
"score": [
3180,
529,
5,
59,
2,
2,
4,
10,
4,
10,
2,
2
],
"text": [
"It's ice. It forms on the fuel tanks becauce the fuel is very cold. What does it do? It falls off. \n\n\n\n\nEdit: Our benevolent overlords have required more details about the fuel and tank. Very well, but no peeking in this section if you are under five. The fuel consists of liquid hydrogen, along with a liquid oxygen oxidiser, both of which have very low boiling points at pressures typically encountered on earth. In order to be liquid at the pressures inside the fuel tank, the fuel and oxidiser are kept at an extremely low temperature. This, combined with relatively thin fuel tank walls (gotta save weight on rockets), means the outer surface of the fuel tank will be very cold, bringing the temperature of the water vapor in the air around it low enough that ice forms on the tank and then falls off as the whole contraption shakes mightily as it takes off. There's no purpose to the ice, it's just a byproduct of the fuel used.",
"It actually is ice. \n\nRockets store their fuel as liquids, so they can be pumped around easily and take up as little space as possible. Many fuels have a boiling point below room temperature, so they need to be cooled down and pumped into the tanks that make up the structure of the rocket itself.\n\nThese fuel tanks need to be as light as possible so that the rocket can carry more useful weight to space as payload so the sides of these tanks are *very* thin. When moist air meets the outside surface of the rocket, water condenses just like on a cool drink glass. Because the fuel is so cold the water turns to ice, and ice forms on the side of the rocket.\n\nWhen the rocket is ignited it shakes violently, causing the ice to break off.\n\nIt is odd that you choose the Space Shuttle as an example, [as this is one example that *does not* have ice falling from it](_URL_0_). The external tank is insulated and the boosters use solid fuels. [The Saturn V rocket is a famous example of the ice falling](_URL_1_).\n\nNB: 'Fuel' in this explanation includes oxidiser. There are plenty of rockets that don't use cooled fuels but this is a simple explanation.\n\nEDIT: I is not ice, as it turns out.",
"I'm pretty sure the ice forms because fuel tanks contain liquid oxygen whose temperature must be below 55K for it to stay liquid.",
"The fuel used in many rockets is made of liquid Hydrogen and Oxygen which have to be very cold to stay a liquid. So the skin of the rocket is below freezing which makes all of the water vapor in the air freeze onto itself. The stuff breaks off upon takeoff because it's not stuck on very well.",
"The shuttle is powered with liquid hydrogen and oxygen instead of gasoline like cars use. \nWhen they are stored, they need to be very-very cold to not make an explosion. \n \nJust like a cold soda bottle, they get wet from moisture in the air, but since the tanks are super-cold, the water freezes into ice. \n \nWhen the shuttle takes off, the vibrations shake off flakes of ice that has built up on the very cold sides. Cool eh?",
"A lot of people are saying ice, but that's not all there is. There is heavy duty paper covering a lot of exhausts and other stuff to prevent water from getting into it during storms. \n\nSome of these covers break upon launch, others fall off or disintegrate when the boosters etc that they are covering get fired. \n\n[Here](_URL_0_) is a great documentary about the shuttle launches. Lots of interesting views, and specific analysis of the white pieces falling of the shuttles. \n\nEdit: I was wrong in it not being ice, edited to reflect that it's not only ice. ",
"It's condensed water that turned into ice.\n\nHave you ever used an air duster? There's a property in physics that says that the temperature of a gas is proportional to its pressure. If you increase the pressure, temperature goes up. If you reduce the pressure, temperature goes down.\n\nWhen you use an air duster, gas escapes and the pressure inside the can drops. As a result, the temperature drops to a freezing point. \n\nThe space shuttle works in the same way, but bigger and with fuel.",
"Surrounding moisture in the air condenses and forms ice particles on the surface of the fuel tanks which contains liquefied hydrogen at the temperature of -423 degrees fahrenheit.\n\nWhen the shuttle takes off, the sheer vibration coming from the vehicle shakes/cracks off the ice from the surface of the fuel tanks. Because we have gravity on Earth, said ice particles drop onto the ground.",
"It is ice, remember their main propellant is liquid oxygen. So it falls off the tank, then evaporates, condenses as rainfall and then it's processed by your local municipality as drinking water. Turn on your tap for some space rocket water.",
"The rocket carries liquid oxygen which is super duper cold. The outside of the rocket is then super duper cold. Florida is super duper humid and the humidity condenses on the outside of the super duper cold rocket. The ignition of the engines shakes the entire rocket really hard which shakes the ice right off the outside of the rocket.",
"While everyone says that the liquid fuel being cold is the reason. A large contribution to this temperature is the Joule-Thompson effect. This is where when a gas gets reduced in pressure it cools off. The same way an air conditioner works. ",
"Take a can of compressed air. Spray it. Feel it get cold. The ice forms on the outside of the can in the same way the ice forms on the outside of the space shuttle; by spraying the can, you're decreasing the total pressure. Since PV = nRT, Pressure = [(amount of gas)*(a constant)*(Temprature)]/(Volume). As the gas exits the rocket, we know the pressure is decreasing, since the gas is escaping, but the volume stays the same, meaning as the gas escapes, the remaining gas inside cools down. You can see this on a hot day with a propane tank as well after grilling."
]
} | [] | [] | [
[],
[
"https://youtu.be/xIoRWIgzvbM?t=1m23s",
"https://youtu.be/y-cv_JJOxGI?t=40s"
],
[],
[],
[],
[
"https://www.youtube.com/watch?v=vFwqZ4qAUkE"
],
[],
[],
[],
[],
[],
[]
] |
||
a5sydq | if looking up personal information on public wifi is considered dangerous, why does no one seem to warn about doing the same on cell phone networks shared by way more people? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a5sydq/eli5_if_looking_up_personal_information_on_public/ | {
"a_id": [
"eboyxr6",
"ebozigv",
"ebp2rgy"
],
"score": [
14,
2,
2
],
"text": [
"In a cell phone network, data is encrypted between you and the tower, this makes it fairly secure unless someone pretends to be the tower\n\nOn public WiFi, if it's open then your data is flying around in it's natural exposed form that anyone can read. If it's a secured network, then your data is encrypted on its way to the access point, but everyone else on the network has the key so they can all see all of your data. This is combined with the possibility that the public WiFi hardware may have been breached and be copying data because your coffee shop isn't going to be a technical expert.\n\nWPA3 will make public WiFi a lot more secure by encrypting everyone's traffic with a different key so people can't read your packets flying through the air",
"Good hotspots like Ubiquiti nowadays will have an Open SSID , but will use device isolation to encrypt data between clients. This does not encrypt your data to the access point , it just makes it so that IPs and MACs are hidden to other open wifi users on same network. \n\nCell phones have end-point encryption similar to this device isolation technique, although with more “checks” and more obfuscation than a completely open SSID network. \n\nSource: worked for a company that set up hotspots in hotels, Dorms, businesses etc ",
"Wifi routers are are consumer-grade gear made down to a price, often set up by amateurs and are not always properly secured. Also, public wifi is a prime soft target for hackers so attracts more hacking attempts.\n\nCellular networks are **not** perfectly secure (it's public knowledge the security services can intercept your phone on 2G and 3G and it's safe to assume the boffins at the NSA etc. are always a few steps ahead) but as their business is built on charging money for access & data-use it's far more secure from the ground up. They are using more complicated and closed protocol(s) that you (often) need specialist gear & knowledge to work with, far higher grade equipment installed & configured by professionals and with a far more strictly managed network."
]
} | [] | [] | [
[],
[],
[]
] |
||
84n30q | in the classical period, being homosexual seemed quite socially acceptable (just based on what i've seen from greeks and romans); why then did the bible have parts in it that discouraged homosexual relationships? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/84n30q/eli5_in_the_classical_period_being_homosexual/ | {
"a_id": [
"dvqr2u3"
],
"score": [
3
],
"text": [
"The original text of the bible wasn't written by Greeks or Romans.\n\nEventually people tangentially related to the late Roman empire collected and translated various texts to compose the modern bible, but they didn't write it.\n\nThe various books of the bible were written by culturally distinct Middle Eastern peoples over a *very* long period of time, and those cultures weren't so forgiving."
]
} | [] | [] | [
[]
] |
||
b7i3yh | why does the world appear faster at night? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b7i3yh/eli5_why_does_the_world_appear_faster_at_night/ | {
"a_id": [
"ejrwa8b",
"ejrweb3"
],
"score": [
2,
4
],
"text": [
" > Ever since I was a kid I always felt like everything was faster at night.\n\nIt's all in your head. Things don't feel faster at night. This is your own subjective experience. There is nothing to explain.\n\n",
"Next time you're in a fast moving vehicle (and not driving) look as far off into the distance as you can, then look right beside the vehicle. Things really far away barely seem to be moving while things really close to you appear to be zipping by. At night, the distance you can see is greatly reduced so all you can see are the things closest, which appear to be moving the fastest, making it feel as though you're going faster than during the day. "
]
} | [] | [] | [
[],
[]
] |
||
2k92w2 | studded tires vs winter tires. | Live near Calgary, Gmc Sierra RWD. I commute 100 km or so a day, inside and outside the city. Which tires should I get and why? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2k92w2/eli5_studded_tires_vs_winter_tires/ | {
"a_id": [
"clj24uv",
"clj27g8",
"clj2ozk"
],
"score": [
2,
2,
2
],
"text": [
"Honestly if studded tires are allowed where you live get studded tires",
"Alaskan here. Not going to ELY5 because I'm no expert. However, I drove with winter tires on a front wheel drive sedan and had trouble stopping and getting traction in bad conditions. Got stuck a few times. The next year I upgraded to mid shelf tires with metal studs and had better traction and stopped better, got stuck in deeper snow less than I did with the tires lacking studs. Haven't looked back since. Really it comes down to how you drive, but the studs IMO are your best bet.",
"Winter tires are made of a rubber that stays fairly soft in cold temperatures. They retain their ability to deform around imperfections in the road, which keeps as much tire-to-road contact as possible.\nStudded tires are normally made of the softer rubber, but include metal studs. On a sheet of ice, studded tires can be great. The weight of the car forces the studs to break into the ice, not unlike a cat's claws. On dry and wet roads, the studs prevent the rubber around them from contacting the road, significantly reducing traction. Braking distance increases quite a bit. They also cause lots of damage to the roads over the years.\nMy advice is to use studless winter traction tires, keep a light foot and plenty of space between you and the car ahead. Driving in snow and ice is dangerous and too many people believe that studs or 4x4 means they can drive like its a sunny day. In the end, the driver will affect safety far more than any tires. In my area, the local race track has courses on winter driving and skid control. You may want to see if any such courses are available in your area."
]
} | [] | [] | [
[],
[],
[]
] |
|
ee7wfu | why is the severity of bad weather so different from when a cold front moves into a warm area, versus a warm front moving into a cold area? | A cold front tends to bring thunderstorms and tornadoes, but a warm front tends to bring moderate, longer lasting rainfall. Why? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ee7wfu/eli5_why_is_the_severity_of_bad_weather_so/ | {
"a_id": [
"fbssru3"
],
"score": [
4
],
"text": [
"Warm fronts tend to slide above the cold air they are pushing out. This means they have a long, horizontal, almost flat border. Since that border is what produces the clouds, the clouds are high up in the air, thin, flat and cover a vast area. So the rain is light because the clouds are thing, but last a while because of the large flat area they tend to cover.\n\nCold fronts are heavier, so they form a tall, almost vertical border. This means the clouds they forms, are very, very tall, but not very wide. This produces a huge amount of rain and other unpleasant weather, but it doesn't last as long. The following picture may help.\n\n[_URL_0_](_URL_0_)"
]
} | [] | [] | [
[
"https://www.vectorstock.com/royalty-free-vector/weather-fronts-vector-2569064"
]
] |
|
2aci9s | why when guys pee it some times splits into a double stream? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2aci9s/eli5_why_when_guys_pee_it_some_times_splits_into/ | {
"a_id": [
"citnce0",
"cito3sz",
"citqyfv",
"citurtv",
"ciu5qtv"
],
"score": [
19,
16,
5,
2,
2
],
"text": [
"sexytime fluids caught in the urethra. ",
"The pee hole isn't a perfectly round hole, under lower pressure the 2 middle parts can close leaving 2 smaller gaps either side.",
"[This helpful video from Hot Rod will explain all](_URL_0_)\n\n[This video will let you know that you are not alone](_URL_1_)\n\n\n\n",
"Usually when I get the double stream it means I have lint caught in the tip of my dick.",
"Sometimes a bit of skin (I'm uncut) gets in the way and makes the double stream, or sprays it like a mist setting on a hose.\n\nSource: I have a penis."
]
} | [] | [] | [
[],
[],
[
"https://www.youtube.com/watch?v=VY6PAkLG2p4",
"https://www.youtube.com/watch?v=XvsTmKzR-jM&feature=kp"
],
[],
[]
] |
||
d2widm | why or how videos on youtube differ so much in quality of image? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/d2widm/eli5_why_or_how_videos_on_youtube_differ_so_much/ | {
"a_id": [
"ezxb9eg",
"ezxbh22"
],
"score": [
2,
2
],
"text": [
"Some people have potato quality cameras, and some people have multi-thousand dollar 8K cameras and everywhere in-between. There is also lossy video compression (used to get a smaller video file size at a given resolution but lowers quality).",
"The 720P is just the resolution of the video it say nothing about the how good the image look just how many pixels the video contain.\n\nHow good it look depend a lot of the source of the video. The video might have been recorded at even worse resolution with a bad camera and the upscale it to 720p."
]
} | [] | [] | [
[],
[]
] |
||
3nj1op | why does placing a plastic bag over a credit card help a device read its magnetic stripe better? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3nj1op/eli5_why_does_placing_a_plastic_bag_over_a_credit/ | {
"a_id": [
"cvojos1",
"cvolo6v",
"cvoonx3",
"cvosxkz",
"cvotqh0",
"cvouf5b",
"cvov55c",
"cvov5sy",
"cvowepd",
"cvowq5v",
"cvowwse",
"cvoygm0",
"cvozyi7",
"cvp10bg",
"cvp16c4",
"cvpavpm"
],
"score": [
2547,
146,
22,
242,
4,
12,
7,
5,
2,
2,
2,
8,
2,
2,
2,
2
],
"text": [
"The black rectangle on your card holds a number. Actually it's a set of numbers separated by delimiters, but that's not important. Just pretend it's one number.\n\nIf your card gets damaged, gaps appear in the electrical reading of the black strip, which means that inconsistencies appear in the number. That's no good; that's cause for error detection to throw the whole thing out.\n\nPutting a plastic bag around the card spreads out the electrical influence of each individual atom in the card. This neutralizes (to some degree) degradation the card, because while the interaction with the reader is reduced as a whole, the relative reduction between the bad parts and the good parts are reduced. Consequently, the machine can read it.\n\nTo simulate what's happening, open up Microsoft Paint (assuming you're on Windows). Write, in huge size font. a number. Doesn't matter what.\n\nNow scribble all over one or two of the characters. I'll bet it it's hard to read the number! Now zoom out until you can just barely make out the numbers. I'll bet you can get the original number you wrote.\n\nIt's the same effect, but through electricity instead of your eyes.",
"It does? This is a TIL for me, i didnt actually know that. Thanks OP.",
"It smooths out the signal, Sonny. Kinda like how looking at zoomed in pixel art is easier if you squint your eyes.",
"The best demonstration I've seen about this is drawing black ink strips on a piece of paper, like a bar code. If you smudge it with your finger, then between the black bars there will be lots of intermediate shades of gray. However, if you put another sheet of paper over it, it will be easy to see the solid black bars and the bits of gray in the middle will disappear. \nSwitch the ink out for magnet card stuff, and that's a pretty simple approximation of why it works.",
"I come from the past, when reel to reel 'tape recorders' were all we had. Putting plastic between tape and read-head would have made the music mighty muffled. Normally, the analog signals read weren't 'true', but needed 'equalisation' before they sounded right. So my guess is that in a modern digital reader, the plastic film makes all the 'bits' muffled, so the reader automatically jacks up the gain/equalisation, and by pure serendipity you might actually be able to get enough to satisfy the checksum",
"The black stripe on the back of the card is filled with magnetic filaments. When the card is blank the filaments are basically laying down. They are not magnetized. The card receives its data using a magnetic encoding head. The encoding head magnetizes the filaments so they stand up. This can then be read by a magnetic read head. (sort of like a barcode)\n\nAs you use your card and swipe it. The read head in the machine basically \"smears\" some of the magnetic filaments. This produces small imperfections BETWEEN the standing filaments. \n\nAs you swipe it, these very small imperfections between the filaments causes the read head to not understand the code. \n\nThe plastic bag is a small barrier to make the machine ignore or not be able to read the small imperfections.\n\nSome scotch tape will act in the same manner.\n\n",
"I just want to know who the first person was to try this. \"Hmm, still not scanning. I'll just throw this plastic bag over it!\"",
"Easiest way ive learned to explain it is this.\nImagine you have a painting. After a while it starts to age. Gets a bit worn, some tears. If you look at it normally you can see all the imperfections. If you look at it while squinting really hard however it blurs the painting a bit. You can still tell what the painting is but you cant see the little flaws anymore.\nReceipt paper also works quite nicely ;)",
"I don't know but I've found a piece of clear tape over the stripe can bring some new life to a beat up card",
"TIL places don't swipe cards anymore. How does the chip work exactly? ",
"As a bartender who gets a lot of worn out cards from guests, the receipt paper works just as well. ",
"Sorry to be dim but I am guessing this is the US? No one has swiped my card in Europe in at least 5 years (although Germany is still fond of signatures) because they all use the chip and pin system.",
"This whole thread is asking \"who uses swipe anymore?\". **Where is the answer.**",
"Related: I'm a cashier, if your card doesn't work the first time, try swiping from the bottom up. It works every time.",
"Working in retail that doesn't have plastic bags around? Use a strip of the receipt paper, works just as well.",
"I remember from an old eli5 that when the strip gets scratched the computer can't read the code. The bag blurs the lines just enough to cover the scratches but still read the code. Similar to when you squint your eyes and look at something like a house. You still can tell it's a house even though it's blurry. "
]
} | [] | [] | [
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
||
491zfq | what are the known psychological effects of long periods in space? | This is a line from a [Bloomberg Business article.](_URL_0_)
> The isolation carries psychological effects, among the most significant and most mysterious aspects of long periods in space. Understanding and ameliorating the psychological effects of extended missions will be critical to any future human exploration of space, because NASA expects these impacts will be larger as mission lengths increase.
I understand that the psychological effects are incompletely understood, but what DO we know? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/491zfq/eli5_what_are_the_known_psychological_effects_of/ | {
"a_id": [
"d0oiuj8",
"d0opa8f"
],
"score": [
3,
8
],
"text": [
"Maybe [this article](_URL_0_) has something you're looking for.\n\n\n\nIsolation and hallucinations: the mental health challenges faced by astronauts",
"From the article it makes it look like bad psychological effects, however, there's such a thing as the [Overview Effect](_URL_0_), in which astronauts change their perspectives about life after seeing the earth as a tiny little part of the immense universe. It ultimately makes them see our problems as meaningless compared to the vastness of the universe and makes them get a sense of humanity as a whole instead of the way we see our geopolitical divisions."
]
} | [] | [
"http://www.bloomberg.com/news/articles/2016-03-04/six-things-that-happen-to-you-after-a-year-in-space"
] | [
[
"https://www.theguardian.com/science/2014/oct/05/hallucinations-isolation-astronauts-mental-health-space-missions"
],
[
"https://en.wikipedia.org/wiki/Overview_effect"
]
] |
|
9xcsng | why does stomach pain from a virus or food poisoning come in waves? | I’ve been struggling all day, and have just been wondering why the pain gets super intense for about 5 minutes, then stops pretty much all together for 10-20? What happens in those 10-20 minutes?
I’m certainly not complaining about those wonderful 10-20 minute breaks, just curious as to why. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9xcsng/eli5_why_does_stomach_pain_from_a_virus_or_food/ | {
"a_id": [
"e9r9322"
],
"score": [
3
],
"text": [
"Many intestinal issues come in “spasms”, wich is a way your guts tell you there is something wrong. It is a short term activity spike (spasm) that we can feel.\n\nI believe this is because most of our digestive tract doesnt have that many nociceptors, thus you feel only the big spikes of abnormal activity.\n\nA constant pain would be unbearable for our body and probably cause you to faint and/or curl in a little ball on the bathrooms corner!\n\n"
]
} | [] | [] | [
[]
] |
|
1le9sx | can you "break" the hippocratic oath? if that's possible, does doing so prevent you from working as a physician? | Is it just a formal thing or does it bear weight?
I imagined it being something like lawyers being members of the bar, and can thus be dis-barred (?), but then again I'm probably way off. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1le9sx/eli5_can_you_break_the_hippocratic_oath_if_thats/ | {
"a_id": [
"cbycivw"
],
"score": [
2
],
"text": [
"It is more a formal thing that you can elect to take when you graduate but are not required to. _URL_0_\n\nYou can break it all you want, so long as doing so does not violate the standards of where you are working."
]
} | [] | [] | [
[
"http://en.wikipedia.org/wiki/Hippocratic_Oath#Modern_use_and_relevance"
]
] |
|
a5hgfy | why did russia decide in the late 1500's to attempt to conquer siberia - an unimaginably large & frigid territory - which would increase the size of its kingdom by ~17x? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a5hgfy/eli5_why_did_russia_decide_in_the_late_1500s_to/ | {
"a_id": [
"ebmk26w",
"ebmn38o",
"ebmn9l3",
"ebmnl86",
"ebmnsd1",
"ebmpb7i",
"ebmqjbz",
"ebmqls0",
"ebmr3w6",
"ebmryjk",
"ebms8y8",
"ebmt7x7",
"ebmxsu9",
"ebn1pjg",
"ebn2nzq",
"ebn341p",
"ebn5oxs",
"ebn9mqv",
"ebnc2gf",
"ebnel85",
"ebniozo",
"ebnjrtv",
"ebnnnv1",
"ebnz3no",
"ebo20er",
"eboij1l"
],
"score": [
8543,
618,
24,
95,
97,
66,
11,
1231,
9,
3,
33,
3,
25,
67,
3,
2,
2,
3,
2,
2,
2,
2,
2,
2,
2,
3
],
"text": [
"The time of Russian territorial expansion was a time of colonialism for all the great powers of Europe. Russia was not well situated to become a maritime power like most of Western Europe, but it did have essentially exclusive access to \"unclaimed\" territory to its east. While Britain, France, Spain, Portugal, and the Netherlands were creating empires for themselves in the Americas and to a lesser extent in Africa and Asia, Russia spread east to Siberia. They were seeking what everyone was seeking, new lands to colonize and cultivate, new resources to tap, new people to spread the gospel of their religion to. \n\nAnd it was \"available\", so to speak. There were not, at the time, any great empires or powerful states laying claim to the territory. Only relatively undeveloped societies, mainly herders and hunter-gatherers, who could be easily conquered and subjugated. Just as Spain and France had laid massive territorial claims in North and South America, so did Russia to the vast northern expanse of Asia. ",
"Russia has always been vulnerable to potential Western adversaries due to its geography. Its heartland is located on the [North European Plain](_URL_1_), completely indefensible due to the absence of natural barriers. Thus, having a backup plan in case of it being overrun is a great idea. Siberia is protected by the Urals from the West. For instance, during WW2 a lot of the industry and parts of the population [were evacuated](_URL_0_) beyond the mountains to support the war effort from a safe distance. ",
"Thanks to Anthropogenic Global Warming, Siberia will probably be one of the only hospitable regions on earth in less than two centuries. \n\n & #x200B;\n\nRussian forecasting, I say.",
"Here is a video that answers this exact question.\n\n\nThe video theorizes that geographic expansion was in order to ensure survival from ongoing invasions (Russia is largely flat, there are few natural barriers to assist in deterring attacks.. so they needed massive buffer space). \n\n\n_URL_0_",
"Not a complete Eli5, but I’ll summarize the best explanation I’ve ever come across, which is [this video from Caspian Report](_URL_0_). Basically, there is long-standing a concept in Russian mindset that ‘geography determines destiny’. The country is flat and doesn’t have a lot of hard geographic borders oceans, mountains, significant rivers, which makes it tough to defend / easy to conquer in many ways. Having land to act as a buffer has been a long-established strategy for stability.\n\n[edit:a word]\n[edit 2: someone beat me to it with the video link. Seriously, The Caspian Report is a fantastic yt channel on geopolitics that is worth a look if you are interested in this subject matter in general]\n\n\n",
"People are not mentioning the great amount of resources available in Siberia, such as minerals and more importantly furs.",
"It was free, nobody else wanted it, why wouldn't you gradually take it? There might be some cool shit over there? Several centuries before Western Russia was barely inhabited",
"There are a bunch of reasons, but like most things human, there wasn't one cohesive decision point or really even a single decision made.\n\n & #x200B;\n\nYou've pointed to the late 1500's - that's the end of the Rurikid Dynasty (the most recognizable member being Ivan the Terrible). At the start of the 1500's, the Russian state as you likely think of it didn't really exist. It was a bunch of loosely confederated city-states with Moscow simply being one of several - and decidedly less powerful than Novgorod, Kiev and Tver at various times. And until 1480, they were still paying tribute to the Tatar Golden Horde. \n\n & #x200B;\n\nBut we're basically talking about the expansions of Ivan IV (The Terrible) since he ruled the Grand Duchy of Moscow from 1533 and was crowned Tsar of All the Russias in 1547. He died in 1584, so we're talking over 50 years. The thing to remember is that he pushed the borders west and south as well as east. He annexed Kazan and was the first Russian ruler to go to war against the Ottomans. He became such a powerful military force that several Siberian states pledged fealty to him and became vassal states in the hope that Ivan and the Russian army would help them against their enemies. Once the boyars (nobility) figured out that not only was Siberia sparsely populated but also rich in things like timber, furs and trade goods, they sent private armies (with permission from the throne) to grab what they could. It took another 100 years, moving in fits and starts, for the conquest to the Pacific to be concluded, and Peter the Great's half-sister, who was ruling as regent for him and his half-brother, concluded a treaty that drew the border with China at the Amur River, where is been (more or less) since then.\n\n & #x200B;\n\nAdditionally, it's dangerous to think of Siberia as a monolithic frozen wasteland - some of it is, especially as you approach the Arctic Circle, but the Russians were working much farther south as well, in some very temperate climates. \n\n & #x200B;\n\nFinally, the Muscovite Rus and the following political entities (including the Soviets and modern Russia) have worked from a \"next hill\" defensive strategy - basically they see the next hill as a threat to their safety and need to take it in order to achieve security. ",
"[Let this guy explain it to you.](_URL_0_)\n\nThat basically is the answer. It was there for them to take and they wanted a bigger kingdom. It is easier to just take the land right beside you than to go across seas like other countries were doing.",
"Also i think George Friedman explained this in his book \"The next decade\" if i'm not wrong. Basically from what i remember they were under attack from nomad peoples (huns, if i remember?) and then decided the best course of action was to just conquer the land for themselves. Also no acces to seashores must've been an important aspect.",
"Russia didn't attempt to conquer Siberia in the 1500s. Russia didn't really exist until 1547. What they did in the 1500s was to establish the Russian empire and to get rid of their muslim overlords in the south. Ivans original obejctive was to expand westward but Russia lost wars to Sweden and Poland. \n\n\nRussia then overthrew the weakening hordes and took Kazan and Astrakhan. After that in 1580s Ivan contracted the Cossacks to attack and conquer the Sibir Khanate. ",
"There's a few theories for it. Some historians view it as more a series of ad-hoc events - for example, there's a tribal group on the border causing problem, you attack to subjugate them and get tribute/stop the attacks... and suddenly there's a new group. Rinse and repeat.\n\nThe other main theory is one of ideology. That is, the Russian empire/rulers deliberately kept pushing east in a more general plan, to secure the frontier (subjugating khanates, tribes, etc), extract tribute (furs, as an example) from the people there, and help open up trade routes to the east. Think of it like this - the Russians knew that Siberia had a lot of fur trading, and that was valuable. The khanates/tribes on their borders were always troublesome. So they went in, subjugating them, and forcing them to pay tribute to them. To guarantee they don't get any ideas, they built forts in strategic places, which then serve as jumping off points for the next series of subjugations/expansion. \n\nSiberia itself took a long time to become anything but a low population backwater of the Empire, or for it to really be colonized/explored in detail. And of course the whole process took over 100 years - that's a long time!\n\n(For more info, check out these: \n_URL_1_\n\n- this is a short answer about some of the reasons behind it.\n\n_URL_2_\n\n- a longer answer about how much the Russians knew about it\n\n_URL_0_\n\n- answers about *how* the Russians conquered Siberia)",
"I think part of the answer is in your question:\n\n > \"which would increase the size of its kingdom by ~17x\"\n\nIt was all about expansion.",
"Expansion into Siberia was originally undertaken by Cossack volunteers. The truth is difficult to discern, but the beginning of the long process of Siberian conquest is believed to have started with Yermak, a Cossack ataman. Cossacks are a unique people, and the only apt comparison I've seen was with the cowboys of the Wild West. They were a fiercely independent people, their livelihood centered around horses, which they also used in wars. Throughout Russia's history, they have been at the frontlines of every war. \n\nIn 1580s, after the end of Russia's war with Rzeczpospolita (at the time, Polish-Lithuanian Commonwealth), Yermak and his Cossacks were hired by some merchants to guard towns against the Sibir khan's raiding parties. Apparently Yermak thought that the best way to deal with the problem was to eliminate the Sibir khanate, and set out with considerable forces, though much smaller than those of the khan. Cossacsk, however, had superior weaponry. Eventually, Yermak took the Sibir town (also known as Qashliq), after which he sent a messenger to the Tsar. Ivan was quite happy with the news, and sent some reinforcements to Yermak. \n\nYermak's story reached a sad end, as he and most of his troops could not survive the Siberian winter (temperatures reached -47C that year). But the Sibir khanate was severely weakened, and when the winter was over, the Tsar's men settled in, founding the city of Tyumen. Russia's hold of the region was made certain, and by the end of the century the last of the Sibir khanate was conquered. Then it just kept going. There were unclaimed territories to the east, and though Russia was already big, men seeking adventure and a share of the land or riches joined the Cossacks that kept going east. The Cossacks mainly traversed the expanse by rivers, rarely venturing by land, unless they could quickly cross to a different river and keep going. As such, the size of Siberia hadn't been too much of an issue, as rivers are a much faster way to travel. Cossacks usually started with diplomacy, offering the locals to swear loyalty to the White Tsar and pay yasak (tax), but it was usually an \"or else\" situation. Often it came to arms, and gun-slinging Cossacks always won. The locals were subjugated, but as Russia was becoming an empire, they were becoming its subjects, which meant roughly equal rights to those of native Russian territories. \n\nSo, the reason for expansion beyond the Urals and the Sibir khanate wasn't wholly the state's command. But as the lands were rich (and though colder than most, they weren't and aren't a wasteland. It's continental climate, meaning cold winters and fairly warm summers), there was no point in stopping. Where the resistance was too great, Russia stopped. It had clashed with China, but didn't keep going when it proved to be too troublesome. ",
"Russia is all about \"buffer zones\" to make sure that, in the event of war, most of the fighting happens on either some other countries' territory, or on territory that can suffer damage without really affecting the country's ability to defend itself. \n\n\nRussia had some really bad invasions from the east -- specifically the Mongolians. When they had an opportunity to forcibly \"annex\" Siberia, they took it. They're also doing that westward, but since countries to the west are populated by people who want no part of any annexation, Russia is facing some opposition there.",
"So it could increase the size of its kingdom by 17x.\n\nBesides, it's a fallacy to think that Siberia is not valuable just because it's frigid. Frigid, \"empty\" land is typically *very rich* in mineral resources. ",
"Extremely high-quality furs were available and the inhabitants were both not as advanced militarily and susceptible to diseases like how native Americans were, so it was easier to take over. In addition to the national glory, their church got converts out of it, too.",
"they probably didnt have to conquer it, just walked in and was like, ya no one lives here, its ours now",
"That huge territory was occupied by the mongol golden horde, which collected taxes from russian principlaities. When moscow subjugated the principalities to itself and started pushing the horde out, moving east, it just didnt stop.",
"To put it simply, because it could. \n\nSiberia was territorially adjacent to areas inhabited by ethnic Russians in Eastern Europe, but it was sparsely inhabited by peoples at lower level of technical advancement, who were not organized into states and could not effectively defend themselves against Russian encroachment. \nIn some ways, this process of conquest and civilization was comparable to what happened in Northern America, but it was less brutal to the native peoples. The technologica/civilizational distance between Russians and native peoples was not as big as between Native Americans and European colonizers. Usually, Russians simply settled on uninhabited areas (clearing land for agriculture) or engaged in similar activities as the natives where agriculture was not possible due to climate (i.e. hunting and fishing). Also there was no comparable effect of disease spread. Native peoples either assimilated to the Russian culture and way of life or (culturally) survived until today. \nSettlement of Siberia was beneficial and supported by the Russian state because it eased demographic and social pressures (esp. pressure for new land). Siberia was settled by escapees from serfdom (peasants were not enserfed there) and adventurists. They enjoyed a sense of freedom there which was denied in European Russia. \n",
"Don’t forget, after occupying Siberia they also occupied Alaska and Tried to claim Northern California \n",
"Russian eastward expansion has many similarities to US westward expansion.\n\nResources, control or benefit from natives, more tax revenue, etc.\n\nThe railroads are what really made the expansion worthwhile. And Jefferson didn't send Lewis and Clark to find and control Wyoming, Idaho, etc. It was about getting to the coast, and having unimpeded access to the coast. This is true for both Russian and US expansion.",
"Even hazardous territory like Siberia can be useful. In at least a few wars, Russia's main defensive strategy was to turn their outermost territory into wasteland. This forces invaders to waste considerable resources just to reach valuable territory.",
"Because it was unimaginably large and would increase the size of its kingdom by ~17x, I imagine.",
"To all the folks saying they did it because it was easy, have you ever been to Siberia? First of all it's cold a hell. The rivers there flow south to north which means when they freeze they back up and destroy the land. Swamps are massive, as are the mountain ranges. Bugs are fucking huge and everywhere, not to mention the bears and gigantic packs of wolves.\n\nImagine going there in the 1500's with primitive technology. One fuck up and you freeze and/or starve to death. It was certainly not easy.",
"Recently learned this in whap... aside from the obvious reason of “to expand”, it would greatly increase the fur trade, helping the economy."
]
} | [] | [] | [
[],
[
"https://en.wikipedia.org/wiki/Evacuation_in_the_Soviet_Union#Evacuation_of_industry",
"https://upload.wikimedia.org/wikipedia/commons/3/38/Europe_topography_map_en.png"
],
[],
[
"https://www.youtube.com/watch?v=HE6rSljTwdU"
],
[
"https://youtu.be/HE6rSljTwdU"
],
[],
[],
[],
[
"https://www.youtube.com/watch?v=yNxPVj0hejg"
],
[],
[],
[
"https://www.reddit.com/r/AskHistorians/comments/21em10/how_did_the_russians_conquer_siberia_how_long_did/",
"https://www.reddit.com/r/AskHistorians/comments/8kn2mh/why_was_the_steppe_trade_route_replaced_by_the/dzc8ws5/",
"https://www.reddit.com/r/AskHistorians/comments/4uch3y/what_did_the_russians_know_of_siberia_before_the/d5pow3x/"
],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
||
44osx6 | what's the difference between an application and a server? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/44osx6/eli5_whats_the_difference_between_an_application/ | {
"a_id": [
"czrq8a0"
],
"score": [
6
],
"text": [
"Think of an application as another word for a program, or a piece of software. Microsoft Word is an application and so is the game of candy crush on your phone. \n\nA server is basically a computer that acts like a central repository of programs or files that many different people can connect to and access. A business might have a server filled with necessary data files, like sales records and customer information, that different employees can connect to and get that information from if they need. \n \nSimilarly, Netflix has servers filled with movies that its customers can connect to and watch those movies from. It doesn't matter what the files may be, if it's serving up files that users request, it can be called a server. "
]
} | [] | [] | [
[]
] |
||
9nbmig | why can only 2/3rd’s of a plastic be recycled? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9nbmig/eli5_why_can_only_23rds_of_a_plastic_be_recycled/ | {
"a_id": [
"e7l4b8k"
],
"score": [
4
],
"text": [
"Certain types of plastics, urethanes in particular, are chemically cured thermoset plastics which cannot simply be melted down to be re-formed into new shapes. \n\nThey do not melt but instead slowly degrade on heating to a variety of toxic compounds. They could potentially be burned as fuel with the proper exhaust handling but the process cost for these types makes them uneconomical to recycle at the moment. \n\nWe are working on bacteria that can break down such plastics, so recycling or at least properly disposing of them may not be such a problem in the near future."
]
} | [] | [] | [
[]
] |
||
4gfmdl | why do tortilla chips not come in individual-sized bags? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4gfmdl/eli5_why_do_tortilla_chips_not_come_in/ | {
"a_id": [
"d2h480c",
"d2h5gg2",
"d2h5naq",
"d2h74w2"
],
"score": [
32,
2,
4,
3
],
"text": [
"Because regular tortilla chips are a bit too bland and dry to eat by themselves and are mostly consumed at parties or a home environment, where they can be dipped in salsa.",
"They do, at least in Canada. They sell them at convience stores and gas stations with little dipping sauce sized containers of queso and salsa.",
"They do sell individually sized bags of tortilla chips. A quick Googles search led to _URL_1_ or _URL_0_ for example.",
"Because why waste your time with chips and dip if you're only going to have that much?"
]
} | [] | [] | [
[],
[],
[
"http://www.amazon.com/Garden-Eatin-Tortilla-Chips-Ounce/dp/B000EQYQBO",
"http://www.staples.com/Tostitos-Crispy-Rounds-Tortilla-Chips-3-oz-Bags-28-Bags-Box/product_364548"
],
[]
] |
||
2dopz2 | how do one-time pads work? | For those unaware, it's a form of encryption that's supposed to be unbreakable. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2dopz2/eli5_how_do_onetime_pads_work/ | {
"a_id": [
"cjrk46f",
"cjrk4mp"
],
"score": [
3,
3
],
"text": [
"Two people get together and exchange some random data. Say we got together and \ngenerated some random numbers, like 16 3 23 8 8 21 0 2, which is the pad.\n\nI want to send \"aardvark\", so I advance all the letters by those amounts, and it becomes \"qdoldvrm\". I send this string to you, and you subtract all those amounts (wrapping round at the end of the alphabet) and you get \"aardvark\".\n\nEven if someone else were to try every possible pad, they would actually end up \"decoding\" every possible 8-letter word. There would be no clue which was the correct one.\n\nThis only works if the one-time pad is truly random, in other words unpredictable. It also only works if we agree on the pad in person. If the pad is transmitted over a network, there's a chance someone could intercept the pad, in which case it's useless.\n\nThese restrictions make it much less useful than the asymmetric encryption which is generally used in internet communications.\n\nedit: Another restriction is that the pad you generate must be as long as the data you send. If you reuse any part of the pad, it's possible for someone to break the encryption. So one time pads will run out, and then you have to meet up again to generate a new one.",
"When the key is as long as the message, that makes it next to impossible to break.\n\n_URL_0_"
]
} | [] | [] | [
[],
[
"https://youtube.com/watch?v=FlIG3TvQCBQ"
]
] |
|
7i53qs | how does sunlight remove stains from clothes? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7i53qs/eli5_how_does_sunlight_remove_stains_from_clothes/ | {
"a_id": [
"dqw6g9o"
],
"score": [
3
],
"text": [
"It doesn't. Sunlight has the ability to bleach things by breaking down their chemical properties via radiation. This is why many plastics will yellow if left outside. But it does not have the ability to actually remove stains from clothing. Some kinds of stains will have the stain break down chemically faster than the other pigments of the cloth but this is not universal for all stains, and even when it does work it is not highly effective. "
]
} | [] | [] | [
[]
] |
||
aoq5hy | why does your house get colder when it's cold outside? is it problem insulation or air flow? | Like do your walls get colder or is the problem that your house has to circulate and probably isn't airtight so cold air gets in? It's weird to think the structure around you is colder. If your walls were really thick or made of special material, could it stay warm in your house? Like your walls acted like a thermal container for hot food? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/aoq5hy/eli5_why_does_your_house_get_colder_when_its_cold/ | {
"a_id": [
"eg2ratf",
"eg2rufy",
"eg2tcaw"
],
"score": [
2,
6,
3
],
"text": [
"Both of those are the major reasons. If you build a truly air-tight house *and* have great insulation on the walls, doors, and windows, you can spend extremely little on heating and still keep it warm.",
"tl;dr because houses in North America are built like shit. \n\nHouses here are built with wood framing for the exterior walls and thin sheeting over that, usually. Fibreglass or rock wool goes into the void spaces between the studs, however, the studs usually still contact the interior wall face and conduct heat surprisingly well. \n\nA side effect of this is that homes are also not very airtight, which lets cold air get in fairly easily.\n\nIn summer, on the other hand, you can bankrupt yourself paying for the ac, and you'll just be wasting that energy.\n\nThere are things you can do, however. If you build with Insulated Concrete Forms or ICFs up to the roof, you can have very thick and very well insulated dense walls. Not only does the insulation keep cold out and heat in, the extra thermal mass of the concrete greatly slows down the rate at which the wall transfers heat. Choose a light-coloured exterior. Triple-pane windows facing south, while expensive, also insulate well, because the thermal gradient gets broken up. What does that mean for your ac bill? What ac bill? Your house stays cool by itself and won't need one.",
"The actual physics answer is that the bigger the temperature difference between two things, the faster heat transfers. So if you have a cup of hot coffee and you want to add cold milk, it's better to add it sooner than later to keep it hot. It you have a hot house and it's cool outside, there will be less rapid temperature change than if it's super cold outside.\n\nThe next part about this is related to how fast certain materials exchange heat. If you touch a metal pole outside, it's feels colder than the air. But really they are both the same temperature. But metal is a better conductor of heat. The goal of insulation is to get more air, wood, and other bad conductors of heat into the side of your home. \n\nSo the practical answer is that it's related to both insulation and air flow. You should make your house airtight in the winter. You should use air as an insulator just like thermal containers do. That means creating gaps in the outside walls for air to fit instead of 1 solid wall. "
]
} | [] | [] | [
[],
[],
[]
] |
|
5mxiex | why do airplains not have enough parashoots for everyone in case of total failure and crash to avoid loss of life? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5mxiex/eli5_why_do_airplains_not_have_enough_parashoots/ | {
"a_id": [
"dc71vrq"
],
"score": [
2
],
"text": [
"This is a repost of a question asked earlier today, but summarizing.\n\n\nMost incidents involving fatalities are close to takeoff or landing, in which case parachutes would be useless. \n\nAccidents involving high altitudes would involve jumping from a fast moving plane at high altitude. It's likely that passengers would pass out either before jumping or mid-jump and not survive.\n\n\nThe weight penalty of a hundred parachutes is huge, and would dramatically increase ticket prices. "
]
} | [] | [] | [
[]
] |
||
53n8cq | how can companies sue people for bad reviews as "liable and slander"? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/53n8cq/eli5_how_can_companies_sue_people_for_bad_reviews/ | {
"a_id": [
"d7uin5v"
],
"score": [
2
],
"text": [
"They probably can't... but they might be able too.\n\nThere is a fairly nuanced (detailed) view of what is and is not slander. A product review is something that should probably be immune... but given what I've seen on the internet it may not be so simple. If people are spamming the review boards alleging things about their product that is categorically not true or personally attacking the company... they might be able to get a libel/slander accusation to stick. "
]
} | [] | [] | [
[]
] |
||
axj03z | how does a v configuration of an engine make it better than a normal engine? | How is a V8 better than a normal engine with the same amount of cylinders? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/axj03z/eli5_how_does_a_v_configuration_of_an_engine_make/ | {
"a_id": [
"ehtv8dx",
"ehtvcp5",
"ehu1305"
],
"score": [
6,
3,
3
],
"text": [
"It's mainly about saving space. 8 in a line is long and thin. Two rows of 4 is only about as long as a 4 cylinder engine but twice as wide. ",
"It is shorter. What you call a normal engine is most likely a straight cylinder engine. In this configuration all the cylinders are placed in a line. However if you have eight cylinders all in a line the engine becomes very long and can be hard to fit. This may not be a problem in for example a bus where a long thin engine can be easy to fit under the floor. However in a normal car this is not so easy. So a straight engine usually only have at most four or five cylinders to fit in the engine bay.\n\n & #x200B;\n\nHowever a V configuration have two rows of cylinders. So a V-8 is the same length as a straight 4. This allows you to fit more cylinders into the same engine compartment. In addition the V configuration allows the cylinder banks to share intake manifold and cam shaft making it overall smaller. In for example a boxer engine where the cylinders oppose each other they need separate manifolds and cam shafts for each row of cylinders as they are too far apart. Another way to reduce the overall size of the engine is to have oval cylinders so they can be placed closer together or to stagger the cylinders from each other. The last option is what the W configuration does which can allow you to fit a W-16 in the same length as a straight 5 cylinder engine.",
"It doesn't from a performance perspective. As everything has said it just makes it more compact.\nFor example: You might fit a V8 engine in your sports car, but if you had to fit a straight 8 engine you would have to increase the size of the engine compartment dramatically, and then it would be more like a truck or bus than a sports car. \n\nThe other advantage is reduced materials and weight. Having the cylinders closer together rather than all apart in a straight line means less material in the block, shorter crankshaft, etc. Huge weight savings and production cost savings. "
]
} | [] | [] | [
[],
[],
[]
] |
|
anrglf | what is particle physics? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/anrglf/eli5_what_is_particle_physics/ | {
"a_id": [
"efvewa6",
"efvg8rd"
],
"score": [
3,
2
],
"text": [
"Particle physics is the branch of physics that investigates the smallest components of matter and energy.\n\nEvery piece of matter in the universe is made up of atoms. Inside those atoms are electrons, protons and neutrons. Inside of the protons and neutrons are various kinds of quarks. \n\nParticle physicists explore the nature and interactions of those particles.",
"That is a rather general question and I am probably not able to really explain it to a five year old. But I will try to simplify. \n\nParticle physics is trying to describe the nature of particles and how particles interact with each other. \n\nBut what are particles?\n\nParticles are the smallest existing things we know. There are compound particles, which are made up of other particles, and there are elementary particles. Elementary particles are not made up of other particles, that is why they are called elementary, they are indivisible. Different particles can do different things. Some make up everything you see, they are matter. Others are are responsible for the interactions between the matter particles. \n\nFor example, quarks make up protons and neutrons. Protons and neutrons make up nuclei. And nuclei and electrons make up atoms which can take the form of any chemical element.\n\nBut gluons hold the quarks together so they can form nuclei. And photons are what light is made of.\n\nSo what does a particle physicist do?\n\nThere are two main types of particle physicists:\n\n1. Think of ways to describe what we know about particles and make own predictions. This type of particle physicist is a theoretical physicist. They make complicated theories that try to explain everything.\n\n2. Do experiments to find out more about the particles. It is hard to tell if some idea of a theoretical physicist actually describes reality or if it is just another fruitless idea. So to find out, you have to measure what the particles actually do. This is very hard as well, as you need to first get the required particles, then have them interact in a certain way and then detect the results of these interactions. Some experimental physicists use particles that were created somewhere in space, others build giant machines to produce and and then collide particles with each other. Both need to build detectors that tell them exactly what kind of particles were observed."
]
} | [] | [] | [
[],
[]
] |
||
9m1m8t | why do thermostats have a heat and cool setting? shouldn’t 70 degrees on heat feel the same as 70 on cool? 70 degrees is 70 degrees. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9m1m8t/eli5_why_do_thermostats_have_a_heat_and_cool/ | {
"a_id": [
"e7b4vzg",
"e7b4xq9"
],
"score": [
7,
4
],
"text": [
"One is where the heater should turn on. One is where the AC cooling should turn on. There should be a several degree space between them, the zone of comfortable temperatures.",
"In winter you don't want the AC kicking on if it gets above 71.\n\nIn summer you don't want the heat kicking on if it gets to 69 overnight.\n\nHeat, Cool, Auto just makes sense. Plenty of reasons to only want one function of the heat pump/exchanger to be functioning."
]
} | [] | [] | [
[],
[]
] |
||
cyi1h8 | how does wind get such speed as 300kph? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cyi1h8/eli5_how_does_wind_get_such_speed_as_300kph/ | {
"a_id": [
"eys3ysa"
],
"score": [
4
],
"text": [
"It always comes down to density, really. All (or almost all) wind comes from less dense air going up and more dense air going down. The bigger the difference in density, more air is moving, or the longer the distance that dense air falls/light air rises, the stronger the winds. The simplest example is a microburst. In a microburst, a column of cold air plummets from the sky due to its higher density, As it falls, it picks up speed, and when it hits the ground it is going fast enough to knock down trees. Hurricanes are just complicated systems of air getting spun due to Coriolis forces and such, but ultimately the input energy comes from the same source."
]
} | [] | [] | [
[]
] |
||
2devyt | why do companies care about their employee diversity? | Just read an article on Apple's disappointment in their diversity and wondered.
Is there an actual business/money making reason for this or is this more about social justice or something?
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2devyt/eli5_why_do_companies_care_about_their_employee/ | {
"a_id": [
"cjou63p",
"cjougf9"
],
"score": [
2,
5
],
"text": [
"Different kinds of people have different ideas and different ways of thinking. If your business often has problems to solve (and most do) it can be useful to have many different perspectives and gender and racial diversity can bring that.\n\nAlso, people tend to naturally value traits they see in themselves. Enforcing diversity can sometimes offset that and result in higher quality hiring.",
"There's a phenomenon called groupthink; where if a company would hire people with same views and stuff - they could not progress fast; and innovation would die, because they would all think the same thing with no one daring to contradict. Sometimes, some healthy conflict in brainstorming sessions would generate great ideas.\n\nApple is losing the touch, because everyone in the company just follows the roadmap that Steve Jobs or whoever brings upon and loses sight of the actual reality of the market; and no one is daring enough to come up with brilliant ideas that would be the next big thing, like the iPod or iPhone.\n\nThus, they could lose innovative ideas or some important aspects when discussing."
]
} | [] | [] | [
[],
[]
] |
|
46ihu6 | is there any unclaimed land in the united states? | I can't imagine that every single square foot of land is claimed by an entity. Does the state own the land that no one owns? How does one go about getting this land? Like, think of the land in the middle of a desolate forest; who owns that? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/46ihu6/eli5_is_there_any_unclaimed_land_in_the_united/ | {
"a_id": [
"d05e9v1",
"d05eh6c",
"d05f7gz",
"d05haka",
"d05kmeo"
],
"score": [
23,
10,
5,
4,
2
],
"text": [
"A vast amount of land is owned by the federal government, including most of the land in the middle of desolate forests.\n\n_URL_0_\n\nSo yeah, all the land is owned by someone, probably the federal government for most land that you wouldn't think is owned by someone.",
"Yes and no. The United States has rarely had much in the way of true unclaimed land, because when it acquired new territory without population it was the property of the federal government or a state. Some of that land was later granted to settlers (the last federal homestead claim was in the 80s in Alaska), but much of it remains in government hands today. The government does not exercise effective control over it everywhere, but formally it is owned.\n\nThere is a lot of land of which the ownership is unclear or disputed, though. Think of how many cities have abandoned buildings with owners that have died or moved away and who have no known descendants. This happens with non-urban plots, too, though somewhat less often. You could claim this land through adverse possession, perhaps, but it's not really unclaimed in the way you had in mind.",
"I'm pretty sure you can still \"claim\" land in Alaska, assuming you are a US citizen and have lived there for more than a year. ",
"_URL_0_\n\nFree land is as good as unclaimed land ... of course it's in Kansas, though. ",
"It actually is all owned. The way land purchases work on a federal level usually involve absorbing another country (like Texas), buying it (Louisiana Purchase and Alaska), or threatening to kick someone's ass (Manifest Destiny and Hawaii). When buying land, it's not like \"I want this land and this land and this land.\" It's more of \"I want all the land from here to here.\" For instance, the Louisiana Purchase was all the land from the US to the Mississippi River. When absorbing another country like Texas, you basically take all of the land from them. Texas fought for their independence in the early 1800's and claimed in the treaty that they get all of the land North-East of the Rio Grande. Texas joined the US and then gave its land to them. Threats are basically the same way, except not as happy. The US wanted Hawaii because they wanted island nations closer to Japan and they had pineapples (that is not a joke, pineapples were the #2 reason for taking Hawaii). The US sent a ship over to Hawaii asking them to join. The queen said no so they sent some battleships over and asked again. The queen signed a deal to give all of her land to the US."
]
} | [] | [] | [
[
"http://nationalmap.gov/small_scale/printable/images/pdf/fedlands/fedlands3.pdf"
],
[],
[],
[
"http://www.freelandks.com"
],
[]
] |
|
56o0w7 | supposedly paper made a few centuries ago had better quality than paper nowadays, is this true, and why? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/56o0w7/eli5supposedly_paper_made_a_few_centuries_ago_had/ | {
"a_id": [
"d8kvp08",
"d8kvrbh"
],
"score": [
2,
6
],
"text": [
"Yes it is true. The reason is because we *chose* to make lower quality paper these days, because it is cheaper.\n\nWe could make paper better than they did centuries ago, there is just not really a need for us to do it. ",
"Wood pulp paper is what we are familiar with today. It is made in a similar way today as it was many years ago. However, today, it is made by machines. Before, it was made by hand. Making extremely thin paper is possible with a machine because you can precisely set up the exact dimensions of paper to create. Because making paper by hand is much less precise, paper-makers would rather make slightly thicker paper to avoid problems, than make paper that is too thin.\n\nNow, that's all talking about modern wood pulp paper. Before modern papermaking, paper was made in different ways around the world, and out of many different materials - like Papyrus, Hemp, and Parchment (animal skin). Note that animal skin parchment is not the same kind of parchment you buy at the store for using to cook. Anyway, papers made from materials like Papyrus or Parchment were thicker and more durable than modern paper, in part because they were made by hand and in part because they were made of better materials (in terms of durability).\n\nYou must also consider the way people used paper before modern paper processing was invented. Prior to the invention of the printing press, manuscripts had to be written by hand in ink. If you're constantly writing in ink, you want strong paper for two reasons. First, you must be able to erase and re-write on the paper. The way you erase ink from paper is by scratching the ink off the paper with a knife. Therefore, the paper has to be relatively high quality and thick to withstand this \"abuse\". Second, the paper must last a long time, because getting someone (a scribe) to hand-write you a document was expensive and they would put many hours into it, so you (and the scribe) would definitely want it to last."
]
} | [] | [] | [
[],
[]
] |
||
45cv3a | what is the difference between a suit and a tuxedo? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/45cv3a/eli5_what_is_the_difference_between_a_suit_and_a/ | {
"a_id": [
"czwx7si",
"czwxb2z",
"czwxdqc"
],
"score": [
2,
3,
2
],
"text": [
"To quote [this site](_URL_0_):\n\n > The primary physical difference between a tuxedo and a suit is the presence of satin. Traditionally tuxedos have satin facing on the lapels, buttons, pocket trim, and a satin side stripe down the leg of the trousers. Suits don’t incorporate any satin and usually have either plastic buttons or buttons faced with the same fabric as the coat (aka self buttons.) Some modern tuxedo options have minimized the use of satin to a thin satin trim on the lapels and a thin satin bead down the pant leg, but the primary difference between the two is that tuxedos have satin on them and suits don’t. Of course, to every rule there are exceptions.\n\n > Other physical differences like appropriate accessories generally only come into play when talking about traditional black tie standards. For most modern tuxedo functions like proms and weddings, the lines between what is appropriate to wear with a tuxedo vs. suit have been blurred. It’s common, though increasingly less so, to wear long ties and high stance vests with tuxedos. However, this is traditionally a look only appropriate with suits. Tuxedos are historically only to be worn with bow ties and cummerbunds or waistcoats (low stance vests.)",
"There are lots of kinds of suits. One type of suit is called a Tuxedo.\n\nThe Tuxedo is characterized by colored or black flat lapels that don't connect, bow ties, a waistcoat/low cut vest, trousers with a stripe down the side that match the lapels, diagonal buttons and a handkerchief in the pocket.\n\nThe Tuxedo is the traditional clothing for a man at a 'black tie' event or for people who work at places that host such events, like hotels. Other types of suits are suited for other purposes.\n\nSo, in short, asking what the difference is between a Tuxedo and a Suit is alike asking the difference between cargo pants and pants. A Tuxedo is a suit, and what differences it has with other suits depends on the suit.",
"A tuxedo is a kind of suit with satin lapels and a stripe down the leg, that conforms to Black Tie dress code.\n\nIt can be used more generically to refer to an fancy, very formal suit, especially those worn by groomsmen at weddings."
]
} | [] | [] | [
[
"http://www.mytuxedocatalog.com/blog/tuxedo-questions-and-answers-what-is-the-difference-between-a-tuxedo-and-a-suit/"
],
[],
[]
] |
||
2halto | if a child was raised in a home where a different accent was spoken around it everyday (7 different accents, same days every week), when it was at the age of holding a conversation what accent would it have? | Hypothetical situation but I've been trying to figure it out. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2halto/eli5_if_a_child_was_raised_in_a_home_where_a/ | {
"a_id": [
"ckqx0dh",
"ckqx8c2",
"ckr3ft4"
],
"score": [
9,
6,
2
],
"text": [
"They would say some words in one accent and then other words in other accents. If the person who spoke in an Irish accent mostly talked about food with them, then food vocabulary would be spoken in an Irish accent. It's also quite possible that the child would speak with each person with the accent of the adult. \n",
"Mostly they would have the accent of whatevers on TV. I always find it hilarious that I have friends who have native accents but their children who have not ever gone to school have these midwestern American accents from watching TV",
"I grew up with a mix of accents being spoken around me and now no one I know has been able to identify my accent. Some kind of chinese/korean/canadian hybrid weird thing."
]
} | [] | [] | [
[],
[],
[]
] |
|
6kql46 | - how do counterfeit pens work? | Further, why do they mark skin as genuine? Like, I mark on my hand and the ink color signifies genuine "money" rather than counterfeit. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6kql46/eli5_how_do_counterfeit_pens_work/ | {
"a_id": [
"djo136c"
],
"score": [
6
],
"text": [
"currency paper is a mixture of cotton and linen with no cellulose. The iodine in the pen reacts with the starch (cellulose) in lower quality counterfeit bills paper causing a dark stain to form. Genuine bills fail to react and the iodine evaporates after a short time. "
]
} | [] | [] | [
[]
] |
|
2tvhuh | how do/can/why do smaller carriers (metro pcs, cricket etc.) offer unlimited 4g data for $50 while at & t/sprint charge upwards of $100? | Further more, why do the bigger companies have more customers than the smaller companies with rates like that? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2tvhuh/eli5_how_docanwhy_do_smaller_carriers_metro_pcs/ | {
"a_id": [
"co2o3tn"
],
"score": [
3
],
"text": [
"Bigger companies have better network coverage."
]
} | [] | [] | [
[]
] |
|
2mpo37 | why is affirmative action rase-based on not class-based for colleges? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2mpo37/eli5_why_is_affirmative_action_rasebased_on_not/ | {
"a_id": [
"cm6fw6x",
"cm6gcym"
],
"score": [
4,
3
],
"text": [
"Student Aid is made available on the basis of income level.",
"A rich black man is *still* not equal to a white man of the same income due to subconscious and not not-so-subconscious racism throughout his life. For example, somebody with a black sounding name is [50% less likely to receive a call back](_URL_0_) for an interview than someone with a white-sounding name, even if the resumes are the exact same. \n \nStudent aid is still available for poorer people, regardless of race."
]
} | [] | [] | [
[],
[
"http://www.nber.org/digest/sep03/w9873.html"
]
] |
||
cg771k | how does the body know what to take in and put out? | For example, how does the body know that it should absorb Vitamin A from carrots, and how does it know what things should be gotten rid of? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cg771k/eli5_how_does_the_body_know_what_to_take_in_and/ | {
"a_id": [
"euf33ej",
"euf3a01"
],
"score": [
6,
5
],
"text": [
"It isn't a question of \"knowing\", the body simply does what the chemistry dictates. Think about a set of interlocking gears, how do they \"know\" to turn in sync? They don't of course, they don't have any way to do otherwise. This is basically how the body works, just with chemicals rather than gears.",
"Don't think of it as picking and choosing. Your body absorbs everything, and different organs like the kidneys or liver filter out anything the body doesn't need. Harmful substances, like alcohol for example, are removed as soon as possible. Vitamins are just chemicals your body needs, and any excess of even those good chemicals are filtered out."
]
} | [] | [] | [
[],
[]
] |
|
5hd2wf | why is it that when you uninstall something on your computer, there are still folders related to what you uninstalled left behind with nothing in them ? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5hd2wf/eli5_why_is_it_that_when_you_uninstall_something/ | {
"a_id": [
"daz978p"
],
"score": [
14
],
"text": [
"On Windows, you can't immediately delete a file that is being accessed by some application or service. Consequently, you can't remove the directory that contains this file, even if you don't need it anymore.\n\nNow, you can tell Windows to delay the file's removal until it's closed (no longer accessed). That's why the file will be gone eventually. However, there's no way to tell Windows to delay the directory's removal until it's empty. Hence, occasional leftover empty directories."
]
} | [] | [] | [
[]
] |
||
1kmrab | how do they simulate the smoking of crystal meth in shows such as "breaking bad"? | I Started Watching Breaking Bad Recently and there are many scenes in which someone smokes meth. I know for films they have developed a form of marijuana that contains no THC for use by actors, so what's the story for meth? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1kmrab/eli5how_do_they_simulate_the_smoking_of_crystal/ | {
"a_id": [
"cbqi2yn",
"cbqim50",
"cbqomir"
],
"score": [
6,
5,
2
],
"text": [
"Its just rock candy that they dont inhale. ",
"You can't have people smoking meth on TV sets, for many reasons that shouldn't need explaining. However, there are plenty of ways to make it look like someone is ingesting drugs. One movie I read about simulated the smoking of crack or meth (can't remember which) by having a couple pieces of broken ceramic, stained brown with coffee or tea, sitting in a pipe on top of a little tobacco. The ceramic looked like the drug, and the tobacco provided the puff of smoke. Viola. ",
"I refuse to believe Meth and Red were smoking fake weed when filming How High............ Same goes for Half Baked and Soul Plane...."
]
} | [] | [] | [
[],
[],
[]
] |
|
8zvxag | from where do you measure height of moutains and depth of seas? | Is there a point somewhere on Earth, which is considered ground level? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8zvxag/eli5_from_where_do_you_measure_height_of_moutains/ | {
"a_id": [
"e2lrvjh",
"e2lteuz",
"e2lweps",
"e2m3uan"
],
"score": [
4,
2,
3,
2
],
"text": [
"Mean sea level is an average level of the surface of one or more of Earth's oceans from which heights such as elevations may be measured.\n- Wikipedia",
"Sea level is used for zero altitude.\n\nActually there are a number of different points used by different countries around the world to determine where exactly sea-level lies.\n\nEspecially if you have more than one coast there can be quite a difference so there are official reference points that each country recognizes. Those may differ by a few centimetre or decimetre, but that doesn't matter much when you are talking about the height of mountains.\n\nSometimes it can result in awkward situation though like when you try to build structure that cross between different regions that use different system. There is a bridge between Switzerland and Germany that crossed such a boundary. engineers were aware that the two countries used different systems and planned accordingly but someone managed to add the difference where they should have subtracted it and the bridge almost ended up with a step in the middle. (They notice and corrected the mistake before finishing construction.)",
"Sea level is tremendously complex. The WGS84 system used for GPS defines the earth & mdash;and therefore its sea level & mdash;as an ellipsoid, i.e., a slightly flattened sphere. But in some places there are more heavy rocks near the surface than in others, making our gravity field quite lumpy. Sea level varies from what WGS84 says by up to about 100 metres as [shown here](_URL_0_).\n\nCountries usually have their own mapping datums which vary from WGS84, just because of this issue and others, like continental drift. Mountain heights will probably be recorded based on some local datum which will generally use some local measure of sea level.\n\nDifferent countries use different standards of what is the exact zero point for sea level although \"mean sea level\" is very common. Even this is difficult to measure because tides go through a 19-year cycle and water levels are affected by atmospheric pressure and winds. And there are longer-term factors like sea-level rise plus land levels rising or sinking slowly in different places. Once you get down to around 1-metre accuracy, it will be difficult to make valid comparisons between mountain heights unless they are close together and measured using the same datum.",
"In the past it was measured from average sea level, but this proved inaccurate due to irregularities in the earth's shape and variations in sea level itself.\n\nThese days there is a mathematical model called the geoid that represents a virtual sea level. The current standard used in most western nations is the World Geodetic System of 1984 ([WGS-84](_URL_0_))."
]
} | [] | [] | [
[],
[],
[
"https://en.wikipedia.org/wiki/Earth_radius#/media/File:Lowresgeoidheight.jpg"
],
[
"http://www.unoosa.org/pdf/icg/2012/template/WGS_84.pdf"
]
] |
|
58b7lj | how do babies know to drink/eat | I understand that in the womb, babies receive all their nutrients through the umbilical cord. But how do they understand to eat with their mouths? Are they born understanding that suckling on a nipple will nourish them?
Why do I even want to know this. Was this covered in biology class and I missed it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/58b7lj/eli5_how_do_babies_know_to_drinkeat/ | {
"a_id": [
"d8yxjq6",
"d8yxw6k",
"d8z9v6y"
],
"score": [
3,
6,
2
],
"text": [
"They are not cognizant of the fact that a nipple will nourish them, it is just an involuntary response. When a nipple-like object is brushed against their lips they'll open up and attempt to latch on after which they will begin sucking. It is all instinct.",
"Sucking and swallowing is a natural instinct a baby is born with. During development the brain just automatically produces that instinct. \n\nIn babies that are born extremely premature, the brain doesn't have time to develop and mature enough to produce that instinct and they have to be taught how to suck, swallow, and breathe all at the same time. \n\nAs they get older, the brain matures even more, and their jaw muscles become stronger, and that allows them to start chewing. ",
"My son crawled to and sucked my breast as soon as he was placed on my chest when he was born. It's one of the most miraculous things that I've ever witnessed."
]
} | [] | [] | [
[],
[],
[]
] |
|
61c8kd | how did ronda rousey go from a role model to a national joke just by losing one fight? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/61c8kd/eli5_how_did_ronda_rousey_go_from_a_role_model_to/ | {
"a_id": [
"dfddmr5",
"dfdfjyf",
"dfdg0ls",
"dfdg5hm",
"dfdhjxv",
"dfdk1w9",
"dfdle1v",
"dfdm0zg"
],
"score": [
3,
13,
12,
2,
22,
4,
3,
9
],
"text": [
"It happens with everyone like that. They are viewed as unbeatable and an idol, until they get defeated once, they they are just a joke. At the moment Connor Mcgregor is viewed as an hero to many, when he loses his first fight the sake thing will happen ",
"The biggest reason comes down to the age-old adage: \"Pride goeth before the fall.\" \n\nHolm dismantled her. I've watched the video probably 20 times, going frame by frame at certain points, and it's actually worse than it looks. Holly is SO far ahead of Rhonda. She's two or three moves ahead, drawing her in, eliciting a punch only for Holly to easily move aside and sock Ronda in the jaw. It's like Holly was fighting a little kid. \n\nIt's like if Superman fought Robin just for LOLs and Robin beat the crap out of him.",
"I think part of it was the overwhelming hype the Ronda received. Rogan spoke of her as \"once, not in a lifetime, but ever in human history.\" Then everybody seemed to think she could beat Floyd Mayweather and males in the UFC. \n\nHolly Holm didn't just barely defeat Rousey...Holm made her look like a clown.",
"It wasn't one fight, that was just when the ball started rolling fast enough downhill that it couldn't be stopped.",
"First, there was a *lot* of hype about her, especially compared to fighters in other weight classes and male fighters. At one point a national publication named her the best pound for pound fighter, male or female. I'm all for equality, but the notion she wouldn't be destroyed by the 100th best male fighter in her weight class is ridiculous. \n\nSecond, she went Hollywood. At lot of the reason she had so much hype was because she was attractive and played that up. That may have caused her to lose some focus, and almost certainly lose respect among her peers.\n\nSo she was overhyped, bought into the hype, then fell from grace. That's pretty much a tragic hero from Greek drama, a time-honored story everyone loves to hear.",
"u/kouhoutek made a lot of good points regarding the climate but I think the national joke comes from the lack of evolution in her game.\n\nRR is still the most dangerous girl in the division once you get to the mat. The problem is she can't get it there without decent striking to set up the take down. \n\nShe's a laughing stock because her striking defense is arguably the worst in UFC history. Take a look at the link - she doesn't even try to dodge. She only moves in one direction and has ZERO head movement. It looks like frankenstein throwing punches. \n\n_URL_0_\n\nShe got exposed in the most horrific way possible. Then instead of evolving, training those weaknesses, she get's smashed in the same way.\n\n_URL_1_\n\nI'm not even going to start on how shitty her coach is. You can hear it from the audio from the 2nd fight\n\nTL:DR One dimensional fighter that road her own hype train to a demolition derby. Refused to dodge punches and got smashed again. ",
"It seems to be peculiar to fighting sports, the megastars are expected to go undefeated, and a single loss seems to be majorly damaging to their career. You don't see that so much in other sports, I don't really know why.",
"Nobody seems to be addressing the role model part of your question. Yes she was over hyped, yes she got wrecked, yes she's not the best woman fight now. That's not why she isn't a *good role model.* You can be an amazing role model without being the best at your sport/position/team. \n\nShe fell out of role model limelight because of how poorly she handled losing. There was no sportsmanship, she spiraled into depression, and everything people praised her for, her work ethic, her grace, and how down to earth she was, completely evaporated. Her ego grew beyond what she could mentally handle and completely refused to change her approach and got stomped again. Whiney people who are too stubborn to bounce back or can't handle getting beat like an adult aren't a role models.\n"
]
} | [] | [] | [
[],
[],
[],
[],
[],
[
"https://streamable.com/os24",
"http://dirtyboxing.tumblr.com/post/155196889101/enjoy-the-fight-with-the-audio-of-ronda-rouseys"
],
[],
[]
] |
||
3gimpv | why is the iran deal good? how do we know that iran isn't tricking us and iran will blow up the whole world with their atomic weapons? | This really worries me and it is giving me anxiety because it's such a terrifying thought. What if we made a bad deal with them and we will end up dead because of it? Maybe Obama has his head in the sand and we are in denial of what Iran's intentions really are? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3gimpv/eli5_why_is_the_iran_deal_good_how_do_we_know/ | {
"a_id": [
"ctyguvt"
],
"score": [
5
],
"text": [
"The whole point of the deal is that yesterday we couldn't watch them and they very well *could* have just tricked us and made nukes, but tomorrow we can watch them.\n\nIt's not like the deal is to smile and say \"Okay Iran we'll stop paying attention now\". The deal is that we're allowed to watch them now. Our ability to prevent Iranian nukes is enhanced, not reduced, by the deal."
]
} | [] | [] | [
[]
] |
|
4gnvwc | why, as you get older do muscles get "wear & tear" whereas you can workout at the gym and get "wear & repair" | What is the difference in this because at the gym you are tearing your muscles so that they will rebuild and grow bigger?
Whereas, as you age I always hear people's muscles deteriorate through "wear & tear"? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4gnvwc/eli5_why_as_you_get_older_do_muscles_get_wear/ | {
"a_id": [
"d2j8biq",
"d2jelvy"
],
"score": [
13,
92
],
"text": [
"I think it's just due to aging. As you get older, you become less active, and more sedentary. The majority of people who go to the gym are young, anywhere from 15-30, and of course, there will be some older people there too. If your goal is to bodybuild, you damage and grow muscle fibre. This process can only be completed through caloric expenditure alongside the proper amount of protein per day. \n\nIn older people, the more common problem is with worn down joints and ligaments as opposed to muscle. Since older people are more sedentary, muscle atrophy begins to become a more prevalent factor. Muscle atrophy is where the muscle literally just wastes away and is lost, due to inactivity of the muscle and improper nutrition. Unless you're a 65 year old with 30 years of lifting, and you eat a good maintenance level of calories alongside the proper amount of protein, your muscle is more likely to waste away as a result of inactivity. Also, as you get older, your testosterone levels plummet, and testosterone is one of the main reasons males grow much bigger muscles in comparison to females. Lower test levels, muscle atrophy and an improper diet are pretty good factors in the reason older people lose muscle. ",
"Wear & tear applies to joints and ligaments. With muscle, the phrase \"use it or lose it\" is more suitable. "
]
} | [] | [] | [
[],
[]
] |
|
9q418n | how does pulling up the knob on a bathtub faucet make the water come out the shower head? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9q418n/eli5_how_does_pulling_up_the_knob_on_a_bathtub/ | {
"a_id": [
"e86fgb9"
],
"score": [
8
],
"text": [
"When you lift the lever ..inside the faucet is a flap. The flap.closes making the water move up the pipe. If you have a small stream and put your hand in front of it..the water goes where there isn't a hand . Same thought"
]
} | [] | [] | [
[]
] |
||
3cjei9 | how a cpu working at 3.00 ghz and 40nm could potentially be less powerful than a cpu working at 2.50 ghz but 22 nm. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3cjei9/eli5_how_a_cpu_working_at_300_ghz_and_40nm_could/ | {
"a_id": [
"csw2k5r",
"csw4dvy"
],
"score": [
5,
2
],
"text": [
"Gigahertz isn't everything. How efficient the CPU is at using cores matters, number of cores/threads, etc. \n\nIntel CPUs (the 22nm one) have stronger single core performance than AMD equivalent CPUs. If the programs you compare (so most games) don't make use of extra cores the Intel CPUs generally come up trumps.\n\nSecondly, lower nm is better, not the other way around.",
"_URL_0_\n\n\nNewer CPUs have higher IPC, meaning they do more in the same time. A bit like having more hands working on the one task. Also more efficient pipelines (think of a factory assembly line)."
]
} | [] | [] | [
[],
[
"https://en.wikipedia.org/wiki/Instructions_per_cycle"
]
] |
||
5zti68 | why do phones measure power as ma and mah, while laptops use watts and wh? | I've always found it a little confusing. I'd imagine this is because smartphones are way newer than laptops are, but then why didn't phones start using watts? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5zti68/eli5_why_do_phones_measure_power_as_ma_and_mah/ | {
"a_id": [
"df0xrdc"
],
"score": [
2
],
"text": [
"Phones use a single 3.7 volt cell so Watt-Hours can be calculated by multiplying AH times 3.7 volts. Laptops use various numbers of cells, so WH gives a better predictor of performance. \n\nAmp-Hours are used when comparing cells of the same voltage. "
]
} | [] | [] | [
[]
] |
|
30w87q | do your internal organs have colour while still inside you? | Because, unless I'm mistaken, colour is the reflection of the left over light that didn't get absorbed (that's right, right?) and light has never been inside you. So technically wouldn't your insides not have colour until light hits them?
Thanks for the insight guys, neat stuff to ponder. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/30w87q/eli5_do_your_internal_organs_have_colour_while/ | {
"a_id": [
"cpweawb",
"cpwefuu"
],
"score": [
4,
2
],
"text": [
"Whether or not light is present, they have properties that cause them to reflect certain wavelengths of light, so I think you could argue they still have a color. Neat question though. What is color? The reflected wavelengths or the properties that cause certain wavelengths to be reflected?",
"Excellent question, and a fun variation of the \"if a tree falls in the woods with nobody there to hear it, does it make a sound?\"\n\nThe answer is no. Just like sound, color is a *perception*. It is a construction of our minds used to make sense of the world. \n\nWhen a tree falls in the woods, waves of air pressure are created at various wavelengths. And if there is someone there to observe those waves, it's perceived as sound.\n\nColor is really the perception of light waves at various wavelengths. If there is no one to observe those wavelengths, and especially if there is no light hitting the objects, then there is technically no color."
]
} | [] | [] | [
[],
[]
] |
|
5pu6v6 | why does the sound of people whispering to each other sound more irritable to our ears, than people talking to each other at a normal tone, while we are trying to concentrate on some work? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5pu6v6/eli5_why_does_the_sound_of_people_whispering_to/ | {
"a_id": [
"dctw5jf"
],
"score": [
2
],
"text": [
"Higher pitched sounds like whispers remain audible for longer distances.\n\nIf you're in a library and someone is whispering, you're more likely to have your brain's innate \"someone is talking, listen!\" sense repeatedly activated."
]
} | [] | [] | [
[]
] |
||
c2dvu8 | what influences the color of snot? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/c2dvu8/eli5_what_influences_the_color_of_snot/ | {
"a_id": [
"erjk8ra"
],
"score": [
2
],
"text": [
"As far as I know is the bacteria-dead cells and how intense the cold is or flu. The stronger the infection..the greener the snot and thicker."
]
} | [] | [] | [
[]
] |
|
3b23gu | the modern purpose of british royalty? | I understand that they bring a lot of tourism, do a lot of work as international ambassadors and some even do a lot of good work for charitable organisations. Yet they do not govern and still cost the tax-payer millions of dollars. It seems that in this age of Celebrity obsession, they could operate as a Family-based organisation, that are independant of the government, yet still achieve all of the benefits that I listed... | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3b23gu/eli5_the_modern_purpose_of_british_royalty/ | {
"a_id": [
"csi37ov",
"csi3c44",
"csi6bnm",
"csi6noy"
],
"score": [
8,
20,
7,
5
],
"text": [
"they bring in more money from tourism for us than we pay in tax. \n200 million from tourism\nwe give them 40 million.",
" > I understand that they bring a lot of tourism, do a lot of work as international ambassadors and some even do a lot of good work for charitable organisations. Yet they do not govern and still cost the tax-payer millions of dollars\n\nThe profit they bring in from tourism outweighs their cost as a tax expenditure. Also, if we remove the Royal Family, the money spent on them doesn't suddenly just disappear, it instead goes to funding a president and then every so often we have to pay to run an election for president too. Plus, the Royal Family pay for a large portion of their own expenses.\n\n > yet still achieve all of the benefits that I listed...\n\nBut there's also a huge drawback. The Monarch is one of, if not the, largest landowner in the country. But as the Monarch they're not allowed to use the lands, a deal struck with parliament centuries ago basically dictates that parliament will pay for reasonable personal expenditure, but gets to use the land of the monarch for their own purposes, at essentially no charge.\n\nRemove the monarchy and then Elizabeth Windsor becomes the highest private landowner in the country, and the projects already built on her land she can charge through the nose for, or simply shut down.\n\nAlso, how would the Royal Family continue to act as ambassadors? After republicanism, they're just regular citizens. They have training, and experience in the field. But unless appointed to the position, they're just people.\n\nAnyway, they don't even cost that much. They cost each person in the country 2p. People lose more than that when coins fall out their pocket. I currently have my lifetime supply of tax to the monarchy in my pocket.",
"Consider the alternative - you could end up with a president, such as Berlusconi, or Putin, or Erdoğan. These guys are at least equally expensive. \n\nIn general, a relatively powerless royal family has its advantages. ",
"Not British, but here in the Netherlands we also have a monarchy. Apart from their role as ambassadors, their work with charities and their connections, they also serve a big role as symbol for the country. \n\nThink of flags and anthems, their purpose is to be a constant part of the national identity, and so are the royals. They're not bound to one political affiliation and aren't replaced every 4/8 years. And when something big happens (positive or negative) they represent everyone, not just the part of the population that voted for them."
]
} | [] | [] | [
[],
[],
[],
[]
] |
|
8kzhcp | how does depression in humans compare to depression in animals? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8kzhcp/eli5_how_does_depression_in_humans_compare_to/ | {
"a_id": [
"dzbp52e",
"dzbtmhv",
"dzbtoao"
],
"score": [
10,
3,
2
],
"text": [
"That is hard to answer because depression in people is diagnosed largely by how they subjectively feel and how they think, something animals can’t really tell us. ",
"It's pretty much same. Monkeys,Dogs and Dolphins are a good example.\n\nBut as humans we get complicated things to handle on day to day basis than them like interpersonal relations,work stress and maintaining healthy sleep patterns along with depression. So it becomes harder.\n\nP.S : I am no expert but a person who has been taking Antidepressants for over a year.",
"I'd say animals start to display signs of stereotypical behaviour such as pacing their enclosure when in a zoo without enrichment (Basic enclosure, no \"toys\" not having to work for food)\n\nAlso when we lost a dog in 2014 one of our remaining dogs who was really close to him was just quiet and subdued for weeks, not really into doing anything. You could tell she was sad."
]
} | [] | [] | [
[],
[],
[]
] |
||
3lodwe | why is there so much meat on chickens when all they do is stand around clucking all day? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3lodwe/eli5_why_is_there_so_much_meat_on_chickens_when/ | {
"a_id": [
"cv7w3e7"
],
"score": [
5
],
"text": [
"Chickens today are bred to have larger breasts, AND they usually get pumped full of hormones to make them grow quickly. I live in an area with many commercial chicken farms, and they all can take a chick straight from the egg to full grown bird ready to eat in less than 2 months. HERE IS THE KICKER. All of my friends who own these operations WILL NOT let their families eat the birds that they sell.. Think about that."
]
} | [] | [] | [
[]
] |
||
3whi6l | why aren't more laws created or changed by grandfathering them in years or even decades from now? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3whi6l/eli5why_arent_more_laws_created_or_changed_by/ | {
"a_id": [
"cxw9i9f",
"cxwbadf"
],
"score": [
3,
2
],
"text": [
"Because a grandfathered in law can still be changed before it goes into effect. Sure, *now* it won't hit hard, but in 10 years when it's about to happen? People in Congress *then* are going to be de-elected if it actually goes into effect. So, they'll put it off, or scrap it.\n\nBesides that, setting a policy to happen in 30 years is frankly stupid. No one has any idea what the state of the world will be in 30 years, and whether that'd be a sensible policy at all at that point.",
"Because reformists are just as short-sighted as reactionaries. No one can take credit for changes that will happen in 2116 in the 2016 election. I like the way you think, though."
]
} | [] | [] | [
[],
[]
] |
||
6m9ajh | how do electricity companies increase the supply to deal with surges in demand like big sporting events on tv and where does the spare power get kept when it's not needed? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6m9ajh/eli5_how_do_electricity_companies_increase_the/ | {
"a_id": [
"djzua9m",
"djzvmfa",
"djzzc7r"
],
"score": [
3,
3,
2
],
"text": [
"They monitor the demand, and they have rapid-response small generating plants (peaker plants) that they will turn on as needed.\n\n_URL_0_\n\nThey work hard to notice patterns in demand so they can predict spikes. Like [tea time.](_URL_1_)\n",
"There's really no \"spare power\". The electrical grid is a careful balance of supply and demand. If the demand is low, power plants are shut down or throttled back to reduce their output. If demand is high, plants are throttled up, the aformentioned peaker plants are fired up, or additional power is connected from outside the local grid. There are some attempts at power storage, like storing heat as molten salt to be used later to drive a turbine or using the spare power to pump water uphill so it can be used later for hydro power.",
"There is a lot of power stored as rotational mass. All the really heavy spinning generators will begin to lose speed when being stressed, freeing up that rotational energy. The peaker plants take over asap. "
]
} | [] | [] | [
[
"https://en.wikipedia.org/wiki/Peaking_power_plant",
"https://www.geek.com/geek-cetera/tea-time-in-britain-causes-predictable-massive-surge-in-electricity-demand-1535023/"
],
[],
[]
] |
||
2kgjwb | why is it seemingly easier to converse with someone face-to-face than it is with someone you can't physically see (for instance, over the phone)? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2kgjwb/eli5_why_is_it_seemingly_easier_to_converse_with/ | {
"a_id": [
"cll2qky",
"cll2qwz",
"cll3qsp",
"cll3tdv",
"cll7hmm"
],
"score": [
23,
3,
2,
6,
3
],
"text": [
"We are very visually oriented and facial recognition is important in bonding and socializing. We also tend to relate to things that look similar to us more easily and without something to look at and remind us of our similarities, socialization becomes more difficult. Besides that, phones slightly distort the sound compared to face-to-face conversing, so you feel even less bonded and less like socializing. Body language also contributes as it allows us to read between the lines, as it were. We can figure out where we stand socially with others by their mannerisms and movement. Without these cues, socialization is further impeded as you become less sure of yourself and your standing with the person. ",
"I'm the same way. I'm pretty sure it has to do with the visual clues we get when talking with someone face-to-face. Body language, eye movement, facial expressions. Sometimes you can read entire sentences between words, when you are actually with someone, if you watch their emotions as they speak. ",
"Hearing Instrument Specialist here! Others have already mentioned the facial cues we take from face to face communication so I will not delve into this too much, but EVERYONE does a degree of lip reading and removing that facet of conversation results in a little more difficulty. \n\nA second issue with non face-to-face communication is that it is virtually always digitized. This breaks down the sound (an analog signal) into digital packets which are then passed from device to device where they are again rendered back into an analog signal through a speaker. Sample rate and bandwidth are critical factors in making the audio signal something we can understand on the other end of the line.\n\nCell phones, for example, compress the data of your voice A LOT, and this is part of the reason it can be really hard to understand. ",
"I actually prefer speaking over the phone. Not a phobia really, but I think I find visual cues distracting from the actual \"meat\" of the conversation.",
"For the Millenial Generation, the obverse would appear to be true. Based on personal observation, it would appear to me that most would prefer to text their peers than even have a verbal conversation with them, much less a face-to-face interaction."
]
} | [] | [] | [
[],
[],
[],
[],
[]
] |
||
bn66y6 | why does strong encryption matter if passwords can be cracked easily through brute force anyway? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bn66y6/eli5_why_does_strong_encryption_matter_if/ | {
"a_id": [
"en2n80e",
"en2px6j"
],
"score": [
3,
2
],
"text": [
"Encryption stores a password in a a secret code. So even if someone can hack a server to find your password, they wouldn’t be able to read it without knowing how to crack the secret code. This is added security. It would be like putting that crappy building lock in a very strong safe/box that can only be opened with a very complex, hidden key. It doesn’t necessarily matter if the password is poor if the security for that password is super strong. However, simple passwords are easier to guess at random. If you can guess a password, there is no need to even hack and translate the secret code. That’s why it’s still important to have a fairly-complicated password, AND use encryption",
"The thing is a good password can't be brute forced easily. A good password protects the account from being brute forced, strong encryption protects the password from being exposed if the database is attacked. \n\nThink of the password being the key to a modern car (push to start), someone without the key can break a window and poke around but they still can't start the car without the key. They would have to steal your key to start it. No encryption would be like older cars where someone can just break in and just hot wire the car without having to steal the key from you."
]
} | [] | [] | [
[],
[]
] |
||
78s11m | magnetotherapy | I just want to know how magnetotherapy works | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/78s11m/eli5_magnetotherapy/ | {
"a_id": [
"dow7ikj"
],
"score": [
8
],
"text": [
"Short answer is it doesn't actually do anything.\n\n\n\nIt's a pseudoscience that people claim actually works. Their is no well done study that shows it as a viable means of treatment. The results aren't reproducible and nothing has passed peer reviewed."
]
} | [] | [] | [
[]
] |
|
4243wb | when will we reach the point-of-no-return when it comes to climate change? how much time do we have left at current trends? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4243wb/eli5_when_will_we_reach_the_pointofnoreturn_when/ | {
"a_id": [
"cz7ih5d",
"cz7jqhd"
],
"score": [
4,
8
],
"text": [
"We have, by some estimates, already reached the point of no return. With the CO2 levels in the air reaching levels not seen in millions of year, it is unsafe for humans. The oceans were 80 feet higher than they are now the last time the CO2 levels were this high and weather much more extreme. We are already starting to see some of the effects with the strongest hurricane and the strongest \"El Nino\" ever recorded happening just last year. Sorry to be the bringer of bad news :(",
"You have to define what you're returning from. \n\nEarth will most certainly continue to spin and heat and cool regardless if any life is still alive on it. \n\nIf you're talking about a point where it is impossible to avoid the ecosystem failing and all life on Earth extinguishing... Then not for a very long time. Bacteria and cockroaches are super-hardy. \n\nIf you're talking about a point where it is impossible to avoid human extinction... Then it's still quite a while. We're pretty resourceful and there's hope we'll be able to live in sealed boxes the rest of our days and not need things like trees.\n\nIf you're talking about some arbitrary amount of disruption to the ecosystem that would have an effect on human activities.... then we're probably already there. \n\nEven if the system has a HUGE amount of inertia and it's pushed WAY past our ability to correct it... we'll still be here tomorrow and the next decade and the next hundred years. But it might be hard to grow any crops in the great Amazon desert by that point. \n\nYou're asking for a sense of scale of the problem, and sadly I don't have a great sense of it myself. "
]
} | [] | [] | [
[],
[]
] |
||
7hhcmn | when we lose a game, why does our body feel a sense of failure even though it's not real? why does our body accept failure at all? what's the point of such a negative emotion? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7hhcmn/eli5_when_we_lose_a_game_why_does_our_body_feel_a/ | {
"a_id": [
"dqqxsmz"
],
"score": [
4
],
"text": [
"We feel the defeat of failure for the same reason we feel success. Knowing that we failed can drive us to try harder next time in the same way that succeeding makes us want to do it again.\n\nSometimes, however, you don't know what you did wrong or how you could've done better, and all you feel is crushing defeat. when that happens, its the same reaction as when something in real life makes you sad, like breaking your phone. That's your body telling you that that thing is bad and should be avoided in the future. You'd be more careful with your second phone after you broke the first one, and you'd avoid a game that you've lost repeatedly (Think of a child who loses a game, then doesn't play anymore because 'the game is stupid')."
]
} | [] | [] | [
[]
] |
||
awyo67 | the difference between "purple" and "violet". | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/awyo67/eli5_the_difference_between_purple_and_violet/ | {
"a_id": [
"ehq2bu5",
"ehqhcyc"
],
"score": [
7,
2
],
"text": [
"There are a couple of different ways we perceive colour. One is that light of a particular wavelength hits our eyes. These are the colours you see if white light goes through a prism, or the colours of a rainbow. Violet is the purple colour you see there, and it is defined as light of a certain wavelength.\n\nHowever, our eyes also mix wavelengths of light together, meaning that we see a much wider range of colours than the 7 in the rainbow. In the case of purple in general, if red and blue light hits your eyes from the same source, your brain would see this as purple. The shade of purple would depend on the amount of blue and red light going into your eye.",
"Great question! \n \nGood on you. \n\n\nSo far, all I see are pseudo explanations. Stay confused and refuse to be bamboozled!"
]
} | [] | [] | [
[],
[]
] |
||
14hw3u | how come i can immediately identity a voice from afar as coming from a tv than an actual person? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/14hw3u/eli5_how_come_i_can_immediately_identity_a_voice/ | {
"a_id": [
"c7daau6"
],
"score": [
3
],
"text": [
"There's two audio production concepts that are are in play here. First one is called \"Frequency Response\" and the other is \"Dynamic Compression.\"\n\nFrequency response can be hard to grasp but simple to explain. Lets say you took one of those cardboard tubes left over from wrapping paper and placed it infront of your mouth. If you spoke through it your voice will now sound boxy, The tube blocks most frequencies that lie within the ranges of treble and bass leaving only the mids, kinda similar sounding to lofi old time radio. This is known as changing the frequency response. Since tv's use speakers and electronics to reproduce sound this sound will feel less natural to your ears because all speakers have an inherent frequency response that is different than most natural sounds. Speakers tend to be treble heavy and lack bass.\n\nNow the other side of the coin is Dynamic Compression. This is not to be confused with data compression where complex computer algorithms are used to make file sizes smaller (ie mp3 technology.) Dynamic compression is manipulation of volume to make the overall sound more consistent in volume. Basically this is achieved by turning down the volume every time a peak in sound goes louder than a certain threshold. The result is that all the quiet parts of the sound are closer in volume to the loud parts. This gives the sound the overall feeling that it is more energetic. The energicness and inherent loudness that stems from this is not naturally reproduced in nature very often so it is much more noticeable. Also almost every piece of audio that is run through a home theater or tv has some form of dynamic compression slapped onto it. It's especially noticeable when watching television because of strict FCC regulations that penalize stations that go over a certain volume. Commercials are excessively compressed in order to grab your attention that much more and are one reason why they feel so much louder than everything else. (ontop of also being averagely 7db louder than most tv shows.)\n\nSo yeah hope that helps"
]
} | [] | [] | [
[]
] |
||
9o1yp5 | why hematocrit (ht) is usually three times the hemoglobin (hb)? | Hey there! Can someone ELI5 the "practical rule" the Ht is three times the Hb? How is this mathematically proven true?
Thanks a lot for the help! : ) | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9o1yp5/eli5_why_hematocrit_ht_is_usually_three_times_the/ | {
"a_id": [
"e7qw2zw"
],
"score": [
6
],
"text": [
"Hi there - there’s no mathematical formula behind this, it’s more of an incidental observation.\n\nHaematocrit is the *percentage by volume* of red blood cells in total blood. \n\nBlood can be simply thought to be made up of plasma, which is fluid, white cells and platelets and red blood cells.\n\nNow, haemoglobin ( to define our other term) is measured as the total heamoglobin amount in a sample of blood. \n\nThe vast majority of this haemoglobin is found within the red blood cells . \n\nThis means that the more red blood cells there are , the more haemoglobin there will be too. \n\nThe important thing to realise is that haematocrit is a *percentage value* and haemoglobin is a *simple concentration* - they can’t be compared directly because they are measuring something in very different ways.\n\nThe ‘ 3 times’ rule of thumb is a quirk of the units we commonly use to measure haemoglobin (g/dL). If you measured haemoglobin in different units, eg mmol/L, the ‘3 times’ rule wouldn’t apply, and presumably another one would, depend on the rough ratio of the two numbers to each other.\n\nI hope this helps ! "
]
} | [] | [] | [
[]
] |
|
1s1x6p | what causes those moments of slight lightheadedness that feel out-of-body/surreal | My roommate and I were discussing these moments that we have both experienced recently. She described her thought process during these experiences as, "I feel like I *could* pass out sometime in the near future, but I know I'm not going to."
Does anybody else know what I'm talking about? Do these moments have a name? What causes them? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1s1x6p/eli5_what_causes_those_moments_of_slight/ | {
"a_id": [
"cdt4ojs"
],
"score": [
2
],
"text": [
"This may or may not be what you're talking about, but as someone stated below it sounds like switching from a sitting or prone position to standing really fast. This can cause a lightheaded feeling known as orthostatic hypotesnion or temporary low blood pressure. Your body takes a short time to adjust to the change in position in order to deliver blood to your brain effectively and keep you conscious. Since your brain is temporarily deprived of optimal oxygen you get this lightheaded feeling. In some people (namely those who are dehydrated and or are on a high dose of blood pressure medicine) this actually does cause syncope (a fainting spell)."
]
} | [] | [] | [
[]
] |
|
9ujb0c | what is the reasoning behind the texas law that says it’s illegal for a person serving (jail) time or out on probation to vote l in a political election ? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9ujb0c/eli5_what_is_the_reasoning_behind_the_texas_law/ | {
"a_id": [
"e94ohcg"
],
"score": [
4
],
"text": [
"I imagine they want to keep people who break laws from influencing the law itself. \n\nBut the end result is just a method to disenfranchise whatever population you want to persecute."
]
} | [] | [] | [
[]
] |
||
6vtybg | why do so many people catch lobsters out of the ocean. isn't it easier and cheaper to raise them in a farm? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6vtybg/eli5_why_do_so_many_people_catch_lobsters_out_of/ | {
"a_id": [
"dm2y47u",
"dm2yhqt",
"dm2zfkk"
],
"score": [
3,
5,
3
],
"text": [
"It would be a massive time investment. If I remember correctly, it takes 5 to 7 years for a lobster to grow to only one pound. ",
"As I understand it, lobster larvae take a long time to mature, as well as requiring a lot of food. \nBut a more likely reason is that there was never a need to because of the massive lobster population off the coasts of places like New England. Only in recent years has the lobster population began to rapidly decline.\n I remember hearing somewhere that in the 1700s they had to make laws prohibiting slave owners from feeding slaves lobster more than 5 days a week due to how easy it was to get. (citation needed)",
"Why pay to raise, protect, feed, and care for a lobster when you can just wander over to the ocean and grab a whole bunch of free ones?"
]
} | [] | [] | [
[],
[],
[]
] |
||
kr4em | how a newton's cradle knows how many balls you have pulled from one side to replicate the motion on the other side? | Specifically, why, when two balls are pulled back and released, doesn't one ball fly out the other side but instead twice as far? I mean that would satisfy conservation of momentum too wouldn't it? [Example here.](_URL_0_)
EDIT: Ok if I were five, I'd just be giving you a blank stare right about now. I'm still not convinced it has everything to do with conservation of energy and has more to do with "elastic collisions" and a very small separation between the balls.
EDIT2: Weld two balls together and all bets are off. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/kr4em/eli5_how_a_newtons_cradle_knows_how_many_balls/ | {
"a_id": [
"c2mimb9",
"c2mk8c3",
"c2mimb9",
"c2mk8c3"
],
"score": [
3,
2,
3,
2
],
"text": [
"A single ball moving twice as fast would satisfy conservation of momentum but not conservation of energy.\n\nEach ball has mass 1kg, and the two balls pulled back and released have speed 1m/s when they hit the third and fourth balls. \n\nKinetic energy of the system = 0.5mv^2 =0.5x2x1= 1\nTotal energy of system= 1 + GPE (gravitational potential)\n\nIf one ball flew out at twice the speed, v=2 m=1, then initial kinetic energy (just as ball starts moving) would be:\n\nKE = 0.5x1x2^2 =2 \nTotal energy=2 + GPE\n\nGPE is the same in both cases so we see that energy is not conserved.\n\nThe only way for conservation of energy and momentum is for the same number of balls to come out as went in.",
"at first i was like: fuckin moron troll\nbut then i was like: holy fuck good question op",
"A single ball moving twice as fast would satisfy conservation of momentum but not conservation of energy.\n\nEach ball has mass 1kg, and the two balls pulled back and released have speed 1m/s when they hit the third and fourth balls. \n\nKinetic energy of the system = 0.5mv^2 =0.5x2x1= 1\nTotal energy of system= 1 + GPE (gravitational potential)\n\nIf one ball flew out at twice the speed, v=2 m=1, then initial kinetic energy (just as ball starts moving) would be:\n\nKE = 0.5x1x2^2 =2 \nTotal energy=2 + GPE\n\nGPE is the same in both cases so we see that energy is not conserved.\n\nThe only way for conservation of energy and momentum is for the same number of balls to come out as went in.",
"at first i was like: fuckin moron troll\nbut then i was like: holy fuck good question op"
]
} | [] | [
"http://www.school-for-champions.com/science/newtons_cradle.htm"
] | [
[],
[],
[],
[]
] |
|
5rcq73 | when planets are visible from earth, why do they appear as stars to us on the surface of earth? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5rcq73/eli5_when_planets_are_visible_from_earth_why_do/ | {
"a_id": [
"dd67rs4",
"dd68tq3",
"dd69fip"
],
"score": [
2,
6,
2
],
"text": [
"Well, they do appear a *bit* different. For example, planets don't twinkle. Other than that, there's not much else which you can discern with your plain eye, so it makes sense for planets to look the same as stars. ",
"They're reflecting light from the sun, just like the moon does. Now imagine that the moon was much further away- you wouldn't see all the craters on it. You'd just see a white dot, which could look like a star. That's the same thing that's happening with the planets. They're just so far away that they look white.",
"The term you're talking about is angular diameter. You can see the disc of the moon, because it's a combination of two things: close enough and large enough. If the moon were much farther away, it would appear as a dot. \n\nOf course planets we can see with the naked eye, are much larger than the moon. However they are so far away, their apparent angular diameter is too small for our eyes to see them as orbs. With a telescope however, we can magnify the light enough to see the spherical nature of the objects. "
]
} | [] | [] | [
[],
[],
[]
] |
||
9mwuw3 | what is with americans and the importance of not impeding the mail? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9mwuw3/eli5_what_is_with_americans_and_the_importance_of/ | {
"a_id": [
"e7hyrpa",
"e7hz52r"
],
"score": [
3,
4
],
"text": [
"And yet, someone broke into my mailbox and busted the lock, which impeded my ability to get mail for a nearly two months before th USPS got around to fixing it, because it's technically the Postal Service's responsibility. \n\nSo neither rain nor sleet is a good slogan, but the mail was impeded.",
"Commerce (especially before the invention of the telephone and internet) is *highly* dependent on reliable mail. Orders, payments, instructions to agents, and so forth.\n\nAmerica, if nothing else, is all about keeping business functioning smoothly. Calvin Coolidge famously said \"The chief business of America *is* business\""
]
} | [] | [] | [
[],
[]
] |
||
3kwheb | how does australia now have a new prime minister without an election? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3kwheb/eli5_how_does_australia_now_have_a_new_prime/ | {
"a_id": [
"cv12avc",
"cv12bl5",
"cv12go9",
"cv12hf1",
"cv14rwm",
"cv18hmm"
],
"score": [
9,
5,
2,
4,
2,
2
],
"text": [
"You vote for a representative for your local area. They may or may not belong to a party. The party or coalition with the most support in the lower house (House of Representatives) of parliament is said to form government. Their leader is put forth to the Governor General to be the Prime Minister which is not a Constitutional position. If the GG signs off on it which by convention they do then that person becomes the Prime Minister. If there's a change in the factional support within a party then they present a new person to the Governor General for Prime Minister.\nYou only vote for your local rep. You don't vote for a party and you don't vote for the Prime Minister (you may if you live in their electorate vote for them but that's only a vote to elect them to a seat in parliament and not as Prime Minister).\n\nAt the end of the day Tony Abbott is still a Member of Parliament. He didn't lose his seat. The people who put him in parliament, the voters in his electorate, still have their representative. \n\nEdit- Elections in Australia are held every 3 years at most but can be called earlier. By convention the Prime Minister can ask the Governor General for an earlier elections. The Governor General can also decide to call an early election. This has happened when supply bills have failed to pass (Federal budgets).",
"The Australian public didn't vote for a new PM. The Prime Minister is the leader of the party with a majority in the House of Representatives. The leader of the party is decided by the sitting members of that party. Tonight the Liberal party decided they didn't want Tony Abbott to be their leader anymore. As the leader of the party is the PM, we now have a new PM. Tony Abbott is still a sitting Member of Parliament",
"In Ireland the same is technically possible. You can be leader without being elected though its never happened",
"It is the same thing as what happened with Julia Gillard. No, we don't vote in a new Prime Minister whenever we want. In fact, we don't even vote in a Prime Minister directly at all - that position is filled by the Party Leader of the party that holds the majority of seats in Parliament (presently the Liberal-National Coalition). \n\nIn Australia (and I believe the same holds true for most if not all the countries you mentioned), voters are choosing just one representative in Parliament for their electorate region. There are lots of electorates, with each having a 'seat' in Parliament, where somebody is elected to represent the people and interests of that region. Government is formed by a majority of these representatives agreeing on which Members of Parliament will hold which roles - typically this will be one of the two major parties, as they have the political inertia to win a majority of seats. Given that each party has a leader who determines the general direction of the party's policy, this person is most usually (I think always so far.. Correct me if I'm wrong) given the office of Prime Minister if their party forms government.",
"In Australia the leader of the party becomes prime minister. So if the Liberals get the most seats they get to be the government, and whoever the leader is becomes prime minister. If he quits, dies, or gets fired then party members have to pick a new leader. Its just party members voting, not the general public. Everybody keeps thier seats and its business as usual, just with a new boss for that one party. Opposition parties have leaders too.",
"Imagine you don't vote for a President, just for representatives. Whoever is the Majority Leader in the House of Representatives, is also the President. If the party with the majority in the house decides to change it's leader, as they often do, then your President changes too."
]
} | [] | [] | [
[],
[],
[],
[],
[],
[]
] |
|
djycs0 | why do things taste good or bad? why and how do our brains associate certain tastes with being pleasant or nasty? | If sugar is so bad for you, why did god make it taste so good? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/djycs0/eli5_why_do_things_taste_good_or_bad_why_and_how/ | {
"a_id": [
"f4948y0"
],
"score": [
5
],
"text": [
"Sugar tastes good because our sensation of taste comes from adaptations that came about when not getting enough food was the bigger concern. \n\nWe have receptors on our tongues that detect certain chemicals. Sugars, sodium, protein, fat, etc. Our brains are built to interpret those things that provide us with calories as tasty, and certain compounds such as bitter things as bad, since bitter was commonly associated with toxins or things going bad in the wild"
]
} | [] | [] | [
[]
] |
|
2hrs6n | how do animals separate living objects from non living objects? | How does an animal perceive machines such as cars, for example. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2hrs6n/eli5_how_do_animals_separate_living_objects_from/ | {
"a_id": [
"ckvfqxh",
"ckvgzkp"
],
"score": [
3,
2
],
"text": [
"It's probably quite a hard one to say for sure since we don't know what goes on in animals heads and they are quite different from dolphins to ants ect.\n\nBut I think it's safe to assume they for the most part may not have a concept of living and non living as we understand it.\n\nA lot of animals are mainly concerned with, can I eat it and does it want to eat me, as well as relationships with their own kind and so on.\n\nBut you could say they probably tell the same way you do, life experiences combined with what it sounds like, what it looks like/how it moves, what it smells and feels like. But then plants are alive, would you think most animals even care? \n\nAs for cars I can't answer that, like I said we just don't know what animals think about.",
"Biological creatures moves about different than inanimate objects\n\n_URL_0_"
]
} | [] | [] | [
[],
[
"http://en.wikipedia.org/wiki/Biological_motion"
]
] |
|
1oejuy | when monkeys learn sign language do they just repeat things or do they sign for themselves | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1oejuy/eli5when_monkeys_learn_sign_language_do_they_just/ | {
"a_id": [
"ccr9f16",
"ccr9jie"
],
"score": [
2,
3
],
"text": [
"Read about Koko the signing gorilla: _URL_0_",
"Koko, the most famous of the gorillas that learned sign language, did a [live chat](_URL_0_) with people over the internet back in 1998. If you read through it you can tell that it's hard to determine how much exactly she understands, and how much of the conversation is colored by the person doing the interpretation."
]
} | [] | [] | [
[
"http://en.wikipedia.org/wiki/Koko_(gorilla)"
],
[
"http://www.koko.org/world/talk_aol.html"
]
] |
||
opmdo | how scripting works and the differences between the different types, i.e.: c, c+, c++, c#, etc... | I am a total n00b when it comes to programming, but I would like to learn. A basic understanding of scripting would be a good starting point, IMHO. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/opmdo/eli5_how_scripting_works_and_the_differences/ | {
"a_id": [
"c3j1f9v",
"c3j1sri"
],
"score": [
3,
2
],
"text": [
"'Scripting' often refers to quick and dirty programming tasks, which are often written in so called 'scripting languages'. These include fully functional languages like python and perl, which are much slower than a lower level language than something like C, but in return they're very easy to quickly write a program in and make it very easy to do simple things. In contrast, lower level languages have to include much more code telling the computer exactly *how* to do things as well as just *what* to do, because the language doesn't tell the computer anything about how to guess what you mean. The appropriate language depends on the occasion.\n\nIf we follow wikipedia's definition of 'scripting language' precisely, 'A scripting language, script language, or extension language is a programming language that allows control of one or more applications.', and it's most accurate to say that a scripting language is something like 'bash' - a popular example of a 'command line'. Using tools like this you can quickly and easily use many different programs to perform a task, for instance the following in bash...\n\n ls -lathr | grep png\n\nwould call the 'ls' program which returns a list of all the files in a directory ordered by date, then the 'grep' program on the output which looks at all the files and returns the ones with 'png' in their name. The important thing exactly what's going on, but that I've written a simple script calling two different programs with different functions to perform a simple task of viewing all the png image files in my directory. (Disclaimer: This is just an example, and not the best way to view png files in your directory).\n\nIf you want to learn about programming in general, including any real understanding of how scripting works, the best way is to choose a language and get started. There are many tutorials online for any popular one. An excellent beginners language is [python](_URL_0_); it is very popular so there is lots of help available, it has a relatively simple and intuitive syntax so it's easy to learn, it has many well developed libraries to perform any task, and it also is excellent preparation for a lower level language as it develops the same basic ideas without the messy details. If you can't learn python and then fairly easily move on to another language like C, you'd never have managed to learn that other language in the first place.\n\nIf you ask other people questions about starting to program, you'll get 15 different answers from 10 different people depending on what their favourite language is. In reality, anything popular will have plenty of material available for you.\n\nEdit: To answer the bit about all the C variants; C was an early low level computer language. It's a set of instructions that are quite close to telling the computer exactly what to do, so some of the things you do in it involve manipulating the individual 0s and 1s stored in the computer memory. This contrasts to a high level language, where such tasks are generally hidden from the user, which gives increased ease of use but lower potential efficiency of the final program. C++ is an 'improved' version of C with many more features and includes object orientation which is an ELI5 topic in itself. There is no C+ as far as I know. C# is a more modern language supporting more modern ideas with some basis in C-style syntax, but I don't think it has much relationship to C or C++ other than that.",
"scripting is actually a further subset of programming, that generally deals with string and file manipulation and little, non-GUI things you want to do. Almost all (to my knowledge) scripting languages are interpreted, which is something I'll need a few more paragraphs to explain.\n\nI really like building things from the ground up, so if you are more of a top-down person you'll have to bear with me. The things inside of the computer, the RAM, the hard drives, the caches and registries which you may have not heard of, are the things that deal with the 1's and 0's you always hear so much about. Registries are these little places where the computer can do math on numbers. So what happens is, you can send the computer these little code words in it's own language, that tell it what math to do, on which register. It can do stuff like multiplying, and dividing, and addition and subtraction, and even other things.\n\nThe computer, in addition to these registers, has a little internal ticker tape thing that it can write and read to. Basically, each little cell can hold a number, and that number can be another instruction. This lets you do cool stuff, like jump to a certain place and do the instruction there. By the time the computer's design is finished, they have hundreds of these little commands the computer can perform in it's own language, just moving numbers around and using it's little ticker tape. It's very impressive what the computer can do at this stage, but it's painstaking work, because the computer's language is all 1's and 0's, and thus is really hard to read for us. So the next step is assembler language\n\nassembler or assembly language is an exact translation of the computer's language. Instead of 0111011010001010010111, it would be something like mov rax rbx, which means move the number in the register rax to rbx. The program that runs this stuff is written in the computer's language, so it's hard work to write, but when it's done it's much more readable than 1's and 0's, if still annoying to write in.\n\nThe next step would be to make a language in assembler. Why? well, because it's easier to read than the machine's language, its easier to fix bugs and such in it. You can make bigger things easier, and bigger things can do cooler stuff. Enter the compiled language. C, C++ (there is no C+, ++ is shorthand for +1 in C) and C# are compiled languages. What this means is that, in assembler or some language the computer has already been introduced to, you write a program that then can take new input in the form of a file. This file is then converted, using that new program, into machine code, the 1's and 0's again. The new program that does this is called a compiler, and how it does it is very involved and difficult, and I've never taken a compiler course. Suffice to say, you define a new language for this specific compiler to read, designed to be easier to read than assembler, and it will convert it back into machine code so the computer can read it. The benefit is that you can do crazy stuff - like instead of pushing numbers around, you can push whole things that are supposed to represent stuff, you could have numbers of any length, etc. The downside is the compiler is never as good as writing machine code as a human would be (even though it takes them longer), so your program is a little slower. But, compared to newer languages, most compiled languages are lightning fast.\n\nThis is because most languages gaining traction now are interpreted languages. What this means is that the compiler now just kinda runs in the background, converting things to machine code on the fly. Many interpreted languages were also written in compiled languages, which already took shortcuts to make cool things happen, so now these interpreted languages are taking shortcuts on top of shortcuts. What you get is a language which, compared to assembler, is orders of magnitude slower, but so much easier to work in. This would be ruby, or python, or haskell, perl, etc. They do really crazy things - for instance, in Haskell you can write a very well-known algorithm (bubble sort) in one line. You can also define lazy lists, that are theoretically of infinite length in haskell. These are things you don't get in languages like C and C++, but if you need something to run fast, haskell is not the language to write it in.\n\nThis is all besides the point that the real way to learn a language is to just jump in. I would suggest finding a tutorial online for python for people who have never programmed before. Python is interpreted, but powerful, and is written to be short and easy to read. It isn't as crazy as haskell with shortcuts, but it's a nice middle ground, as many interpreted languages can be math and theory heavy"
]
} | [] | [] | [
[
"http://python.org/"
],
[]
] |
|
cckmi1 | is there a reason the color blue doesn’t appear very often in nature? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cckmi1/eli5_is_there_a_reason_the_color_blue_doesnt/ | {
"a_id": [
"etnk86w",
"etnkssy",
"etnnarn",
"etnnt0p",
"eto17oh",
"eto2rmd",
"eto35z7",
"eto7gw5"
],
"score": [
9,
54,
55,
1002,
8,
4,
98,
2
],
"text": [
"I found this article cause I also wanted to know, if you're in for some reading: _URL_0_",
"I suppose it might be hard to manufacture the pigment for blue, many of the blues we see in nature are more due to their structure such as in bird feathers. Birds have lots of blues and there are a number of species which have blue feathers. \n\n & #x200B;\n\n I believe it's not exactly rare in nature, but it is rare in mammals.",
"Except the ocean and the sky?",
"Edited, because hoo boy did I get this wrong/backwards and wow I am so sorry folks. Don't answer science posts drunk, my friends!\n\nFor people who want the answer quick:\n\n*Red* was a later color to evolve in eyesight for a lot of animals, because most plants are green and brown, and dirt/dead stuff is also often brown. Because of that, when animals were camoflaging themselves, especially on land, they evolved to be brown, yellow, or red. Because the animals couldn't see red, that red looked brown. However, they could tell the difference between blue and green because it helped them pick apart their surroundings (ex. A tasty plant is a lot easier to find when it's not the same color as the rest of the ocean). So, an animal that looked too blue in green or brown surroundings would stick out and be eaten. \n\nThe late appearance of seeing red is likely because colors other than green aren't super common in plants. This is thanks to the most efficient kind of chlorophyll, green chlorophyll. Even though our sun makes more green light than other colors, the light that chlorophyll gets energy from are red and blue wavelengths! That's why plants are usually green, is because it's the wavelength they reflect. Lots of animals *can* see blue, like dogs and cats (and us!). Even cooler, lots of animals can see light that *we can't* and have colors on their bodies for that. For instance, butterflies can have UV markings on their wings!\n\nOf course, there are some animals that are still blue. Usually this is because it was helpful for them to find mates. For reasons still puzzling, blue pigments didn't generally arise in animals, and possibly because of this, *green* pigments are also very rare. Many of the green animals you see are actually yellow pigmented, with special blue structures built in!\n\nThis is because (for some reason) it was easier to make blue by making the light shining on them reflect blue with these special structures on feathers, scales, or even in skin like with the poison dart frog, instead of with a pigment. Any time a new trait arises, evolution can find some really cool ways to build those DNA blueprints that you wouldn't expect. This is a very good example.",
"There is a really interesting podcast about colour that I listened to a few years back. It talks about the colour blue, and how even in literature it doesn’t come up until a lot later than you’d imagine because maybe we just couldn’t see it before.\n\nHere’s the link: _URL_0_",
"\"Not a lot of blue\" \nThe ocean: am I a joke to you ??",
"Maybe a bit late to answer, but I wanted to chime in with a different perspective: there is also a reason why *fruit* are rarely blue. It is because most fruit are acidic. I don’t know the exact biochemical link, but acidic things are more often redder and alkaline things are more often bluer.",
"Interestingly, many languages in the world do not distinguish between blue and green. See: _URL_1_\n\nAnd:\n_URL_0_\n\nI was in the Peace corps in Kyrgyzstan and during language training they taught us words for blue and green, but in practice people used the word that supposedly meant “blue” for the sky, grass, unripe fruit, etc. It really meant both colors."
]
} | [] | [] | [
[
"https://bestlifeonline.com/blue-in-nature/"
],
[],
[],
[],
[
"https://www.wnycstudios.org/story/211119-colors"
],
[],
[],
[
"https://en.m.wikipedia.org/wiki/Blue–green_distinction_in_language",
"https://www.wnycstudios.org/story/211213-sky-isnt-blue"
]
] |
||
4d6px6 | taurine, its role in bodily functions, and why it is in energy drinks | What it do | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4d6px6/eli5_taurine_its_role_in_bodily_functions_and_why/ | {
"a_id": [
"d1o75zn"
],
"score": [
9
],
"text": [
"It's an amino acid which is widely distributed in the tissues of the body and manufactured by the body if the person has a normal diet. It is in energy drinks because the manufacturers make money using a version of the following fallacious argument: X is essential to physiological system Y, our product contains X, therefore our product will improve performance of physiological system Y."
]
} | [] | [] | [
[]
] |
|
6x6z54 | why do anti-biotics have to be taken at regular intervals? | Posted this earlier, removed as a repost. After a search, my question is still unanswered.
I'm currently on a prescription for a chest infection, and my anti-biotics have instructions to be taken at regular intervals throughout the day. Does this have an impact on the efficacy of the anti-biotics? Is it more for remembering to take them? Why the regular timing? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6x6z54/eli5_why_do_antibiotics_have_to_be_taken_at/ | {
"a_id": [
"dmdjqzg",
"dme8u96"
],
"score": [
5,
2
],
"text": [
"The goal is to keep the amount of the antibiotic in your system consistently high. If you were to just take a dose and then throw the rest away, the only bacteria that it would kill would be those not well adapted to deal with the antibiotic. Those with adaptations that allow for some degree of resistance would still be there and take their place. In order to ensure that you're not essentially breeding antibiotic resistant bacteria in your body you need to keep the treatment up consistently for a long time.",
"Because you need a high level of antibiotics in your system, all the time, for long enough to ensure all the harmful bacteria are dead. If the level is too low, or high sometimes and low sometimes, then not enough bacteria will be killed, and bacteria that are resistant to the antibiotic will have a chance to multiply more than the weaker ones, which is even worse.\n\nFor all of these reasons, you need to take the antibiotics as directed by your doctor, and not stop until your doctor says it's OK."
]
} | [] | [] | [
[],
[]
] |
|
2or35l | why is the body of a 400-lb person able to carry around 200 lbs extra day after day, but a healthy 200-lb person who weight trains extensively would be exhausted carrying 200 lbs for an hour? | I know a man who weighs in at a little over 400 pounds. He is at least 200 lbs overweight and has gained the weight over 4 years. He leads a pretty normal life.
On the other hand I know a guy who has weight-trained almost every day for 4 years. He could pick up a bar with 200 lbs of weight, but an hour of carrying it around would leave him absolutely exhausted. In the same 4 years he could have gained 200 lbs like the other guy and be carrying the weight around every day.
What is going on in each person's body to cause the difference?
Thanks!
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2or35l/eli5_why_is_the_body_of_a_400lb_person_able_to/ | {
"a_id": [
"cmpp3pl",
"cmpp4vh",
"cmpqtcr",
"cmpqx46",
"cmpw85m",
"cmpxat4",
"cmq05tk",
"cmq2knk",
"cmq3mh2",
"cmqaeca"
],
"score": [
116,
17,
2,
5,
2,
10,
2,
2,
2,
2
],
"text": [
"A 400lb man's weight is centralized to his frame, spread throughout his entire body. There would probably be excess around his mid frame, which causes a lot of overweight men to have back problems.\nbecause of this increase in mass, the overweight person has more blood with which to oxygenate his muscles, making it possible for him to heft his heavier body around.\n \n\nI postulate that a 200lb man that is in peak physical condition could indeed carry 200lbs around with him all day if the weight was closely tied to his frame, such as with a weight vest. Because the weight would not throw off his center of balance, fatigue would be much lower.\n\nCarrying around a 200lb backpack is not about the extra weight, but the rotational forces it places on your spine due to changing your center of gravity so much.",
"Firstly, you'd find that most people who weigh 400lb don't move anywhere near as much as the average Joe, precisely because they weigh so much and it's just so much effort. This is why morbidly obese people can lose weight simply by walking more (which probably wouldn't have much of an effect on the body compositionally of an average sized person), because they aren't accustomed to it the way other people are. Obese people will often have joint problems because of the stress their joints are under from all their weight. So they aren't carrying around their 400lb body with anywhere near as much ease as a 200lb person carries themselves. \n\nSecondly, over time as someone gets heavier and heavier their body adapts. It has to, really. It takes years for someone of average height to reach a weight of 400lb and the increase in weight is hardly noticeable on a day to day or even month to month basis. The accumulation of this weight over the years results in an accumulation of strength in the muscles and joints to support it. The average Joe who lifts weight in the gym can't expect his body to adapt to a similar amount of weight in such a significantly shorter time period.",
"A 400 lb person may well be exhausted after walking for an hour. :(",
"Just an educated guess, but I think it has to do with the weight distribution forcing the 200 lbs man to use weaker muscle groups.\n\nImagine having a 10 lbs weight at the end of a bar. It's fairly easy to lift it with the heavy-side down. You're mostly using stronger muscle groups to lift it (lower back, biceps, legs, etc). Heavy-side up, however, you are also using your core muscles to keep it balanced, in addition to the other muscles to keep it lifted. Same weight, but MUCH harder to keep lifted.\n\nI'm guessing that it's the same difference here. The 400lbs man has the weight evenly distributed. For standard activities (i.e., walking), he will have an easier time than the 200lbs man. However, evenly distribute the weight on the 200lbs man (say, make him wear 200lbs of plate mail), he's probably going to last longer than the 400lbs man (and be capable of more strenuous activity).",
"And something I always wondered that's kinda linked to that : How come that an obese person doesn't loose a shit load of weight just by carrying himself around, since weight lifting is like one of the highest burning calorie workout?? (probably stupid question but I don't really understand)",
"As someone who used to weigh just shy of 400lbs and has since dropped to just over 180, I can say that one simply does not FEEL like they are carrying any more weight than the next guy. I feel the same now that I did when I was overweight. \n\nThe reason the 200 pound body builder gets over-exhausted after only a short while is because he is only conditioning his body and muscles to temporarily hold weight. A morbidly obese person carries that weight with them everywhere they go.\n",
"Fat people can be surprisingly strong. I used to wrestle and we had the fat kid on our team, and I was in much better shape than him but I still had trouble with him. \n\nSimilar to how it can take multiple people to restrain an obese man. The muscles are conditioned to support the weight all day and can be very powerful in bursts as a result, yet the heart is under a lot of pressure and can give out if it exerts too much.",
"I'm an almost 400-pound guy and I'd be glad to answer any questions for you. \n\nI do lift weights 2x a week, walk/jog 2x a week, and about to get into swimming laps. \n\nIt's very true that my high-intensity endurance is pretty low. Short sprints (25-50m) and fast stairs put me out of breath pretty quickly. Long distance walking/jogging will have me huffing and puffing too.\n\nI can only do 5 push ups or so before having to rest for about 20 seconds then I can do 5 more. I'm up to 4 sets of 5 now and getting better, but it's hard to push up so much mass. Oh, and I'm doing them on my toes like I've been taught. \n\nPull-ups. Nope. \n\nLeg press? The whole stack, 3 reps. 1200+ pounds I believe. 800 lbs x5 reps, 3 sets. Working on getting up to 8 or 10 rep sets. \n\nBench press isn't too good right now. I went through some tough times with being unemployed and without real gym access so my max is barely 160 right now. I'm sure I'll get up near 200 again like I was in college. \n\nI can carry all my groceries up 3 flights of stairs in one go. The limiting factor is the bulkiness of the bags or the thin plastic digging into my girlishly soft hands. \n\nFeel free to ask me anything you'd like about being a decently mobile/normal fat guy",
"as a 39 year old 6'3\" 320lb guy here are my thoughts.\n\nI feel mostly like i did when I was a 195lb young man at 21.. at rest...\n\nIn motion I notice the difference.. I am still recovering from a 2 hour soccer game I took part in with my 10 year old daughter right before Halloween.. I have never had any kind of joint problem but my knee has not been the same since that soccer game. I did not hurt myself... it just started a spiral of destruction to my knee.. I ran ..kicked...almost the entire game.. I thought I was going to die...but I did not.. it was fun. As part of my job I climb on structures from time to time and I have no problem doing this.. I can still do push-ups in sets of 30 on my knuckles (how I was taught) and I have not tried a pull up in a few years but..yea maybe? \n\nthe main part is I never jump off of anything and I am careful how and where I sit because I can wreak shit. I don't run and between work and my computer game addiction I rarely stand for more than an hour a day.. \n\nI am going to have to change my habits or it will kill me....someday....some..day..",
"Most 400 lbs people (not fat people, not even obese people, but 400 lbs level of obese) don't move \"easily\" and remain limber as they do normal people things like climb a few stories of stairs, hike, play pickup basketball, etc. Even walking 1 mile is tough for some 400+ lbs people, although certainly not all. You might just know a friend who was an ex-athlete who happened to balloon up - I have a few friends in the 300 lbs range and they spend a lot of time huffing and red, just like what would happen if a 200 lbs strength-training dude was carrying an extra hundred or two hundred lbs. \n\nNot all 400 lbs people have the musculature of NFL linemen; many DO struggle to heave their weight around. \n\nAlso, the reason it's hard as hell for a 200 lbs guy to carry 200 extra lbs all day is that there's always going to be one \"weakest link\" muscle. IE if he carries it farmer's carry style with 100 lbs in each arm to the side, his forearms will be the weak link and give out, because a massive load is placed upon them. If he puts it on his back, his back and shoulders will give out. If he carries it scooped up, like a bundle of logs, his biceps will give out. \n\nIf you should somehow magically distribute the 200 lbs such that 90% of the person's muscles were engaged, and larger muscles happened to bear proportionally greater percentages of the load... then the 200 lbs guy could probably handle the load all day. "
]
} | [] | [] | [
[],
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
|
2ys329 | why does my car's battery die after a month without being driven? | It's just been sitting outside, the weather's been good, and the headlights weren't left on. Where did the electricity go? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ys329/eli5_why_does_my_cars_battery_die_after_a_month/ | {
"a_id": [
"cpceiyd",
"cpcert4"
],
"score": [
3,
3
],
"text": [
"If your car has an alarm it's going to be using the battery for power",
"Car batteries come in different types and some cars use power while not being on for things like an alarm or a light on a dash or something to that effect. Eventually the batteries die like this. Sometimes if a battery has been storing for a really long time it will simply lose its charge. third is due to the battery losing done of its charge in other reactions which can eventually completely discharge the battery. Most car batteries are able to be completely recharged and run for a long time if properly maintained. "
]
} | [] | [] | [
[],
[]
] |
|
789jse | how does a toxicology test work? | When a person's blood is tested for drugs, how does the lab determine which drugs are present? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/789jse/eli5_how_does_a_toxicology_test_work/ | {
"a_id": [
"dos2y52"
],
"score": [
3
],
"text": [
"Using analytic equipment. There are machines called Mass Spectrometers that take a sample, and can display the mass, and rough percentage of how much of the sample is comprised of the given compound.\n\nSo if I run a blood sample through a typical gas chromatography mass Spectrometer (or GCMS for short) for a drug test or something, all I have to do is look through the printout to find stuff with the same mass as common drugs (or their metabolites) to determine whether or not you ingested drugs. Mass spec doesn't give names or anything on an analysis, you need to know the mass of what you're looking for to pick it out of the list, and even then, there's lots of funny reasons you will see head scratching data."
]
} | [] | [] | [
[]
] |
|
1rdjrw | how come when you use a faucet in tall buildings, water comes out? how does it 'flow upwards'? | I've heard of pumps, but even in 3 story homes without a pump it still flows up to come out the faucet. On that note, how is water pressure made? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1rdjrw/eli5_how_come_when_you_use_a_faucet_in_tall/ | {
"a_id": [
"cdm52mj",
"cdm65j1",
"cdm8ykx"
],
"score": [
2,
2,
2
],
"text": [
"There is always a pump.",
"A lot of large buildings will have their own pumping station and a reservoir on the roof. ",
"This is part of what I do at my job, so maybe I can help explain.\n\nThe water utility comes to our buildings between 60 and 80 psi. This is achieved by various pumping stations that maintain the pressure. Once we get the water, we calculate how much pressure is needed to overcome the force of gravity. We have to have enough pressure on the top floors to flush toilets and power sinks. The way that we maintain this number is through what we call a \"domestic water pumping station.\"\n\nMost of the ones where I work consist of 2 pumps (each with its own motor) and a controller. The controller houses all the computers that regulate the pump motors. Long story short you tell the computer what pressure to maintain and it checks the current pressure (using a pressure sensor) against the number you told it (called a \"setpoint\"). Based on whether the pressure it reads from the sensor is higher or lower than the setpoint, it will either increase or decrease the speed of the pump motors to maintain that number."
]
} | [] | [] | [
[],
[],
[]
] |
|
5f33vi | why are pages in textbooks divided down the middle or sometimes into three columns? | It's annoying and makes it hard to read, is it supposed to have the opposite effect or something? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5f33vi/eli5_why_are_pages_in_textbooks_divided_down_the/ | {
"a_id": [
"dah3rzi",
"dah3tml"
],
"score": [
13,
4
],
"text": [
"Simply put, it's easier for people to read short lines without losing track of where they are. If the lines get too long, it's harder to scan back to the beginning of the line without losing track of where you are making it harder to read/comprehend/retain the material.\n\nIt's a pretty straightforward typographical principle - optimal line length is in the ballpark of 50-60 characters. Since textbooks have physically larger pages, you use multiple columns of text to keep line lengths manageable. ",
"This is absolutely not unique to textbooks. It is normally done when pages are wide enough that it would make it hard to follow a complete line, so the page is divided into columns. "
]
} | [] | [] | [
[],
[]
] |
|
ynn45 | how come raw eggs are bad to eat now? 20 years ago, i'd put a raw egg in a milkshake and eat the hell out of cookie/cake/brownie batter. now if i do it, i get sick. what happened? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/ynn45/eli5_how_come_raw_eggs_are_bad_to_eat_now_20/ | {
"a_id": [
"c5x77iz",
"c5x7buq",
"c5x8qpw",
"c5xa9ek",
"c5xcyvq",
"c5xefck",
"c5xm3f6"
],
"score": [
22,
6,
2,
4,
2,
2,
2
],
"text": [
"If you are a healthy person with normal immune system, then raw eggs are just edible as they were before. However people with compromised immune system are more at risk of contracting serious salmonella infection (which is rare, but if it happens it can be life threatening, even on otherwise healthy people). Restaurants and food production companies need to protect themselves from lawsuits, so they need to warn patrons that there might be a danger in eating raw eggs. ",
"Also I think it is mostly the shell that contains all the bad bacteria rather than the egg itself..",
"I read a TIL a few months ago that said only 1 in 20,000 (or something like that) eggs have salmonella\n\nFree upvote to anyone who cares to link that",
"The risk of salmonella (flu++) is somewhat higher now because of factory farming, but mostly it's just that people nowadays like to get overexcited about things. One personal will die from a bad raw egg and because every news outlet will report on it, it looks like an epidemic.",
"**Chicken egg (n.) */CHIK-un EG/*:** A magical foodstuff that can be used as a binding agent, a leavening agent, a thickening agent, an emulsifier, a clarifier, a glaze, and many other things. It's shell is excellent for composting. Ironically, chicken eggs come from the least clean part of one of the most disgusting animals on Earth. In addition, they are typically raised in the most horrific factories imaginable--so at the *very least* they should be cooked before consumption. ",
"I've eaten raw eggs on a fairly regular basis for most of the 27 years of my life and I've never gotten sick. I've had 2 friends claim that they got very sick from undercooked eggs, but one ate them at some tiny roadside diner and the other has a kitchen that probably gives anyone who dares enter a case of dysentery. So I think as long as you buy fresh, quality eggs and keep your cooking space clean, you'll be fine.",
"E.coli and salmonella have managed to figure out how to get into the reproductive system of chickens. Alton Brown, from his first Egg Files episode, had someone from some government agency quote some number, like 1 in every 50k eggs may be contaminated.\n\nAs Alton says, and I agree, the chances of you finding a contaminated egg in your own home, that is actually bad enough to make someone sick, is so small, you may never see it in your lifetime.\n\nMost food poisoning from contaminated eggs comes from the food industry, restaurants. The problem occurs from mishandled eggs, if they're left out and unrefridgerated.\n\nI mean, the possibility of a cart of eggs being left out on the shipping dock behind your grocerry store isn't zero, but if that's what they're doing, I think there are already other signs of contaminated and spoiled food, you'd be shopping elsewhere, and such businesses don't stay open for too long.\n\nI eat raw eggs without concern, and I've never been sick. If you are paranoid, you can always get pasturized eggs. They've been hit with a microwave to kill any potential contamination."
]
} | [] | [] | [
[],
[],
[],
[],
[],
[],
[]
] |
||
364cme | how is the death penalty seen as justice and not revenge? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/364cme/eli5_how_is_the_death_penalty_seen_as_justice_and/ | {
"a_id": [
"craloby",
"cramu7g",
"cramz9k",
"crapr4b",
"cratjkf"
],
"score": [
6,
2,
2,
2,
2
],
"text": [
"Who says it can't be both? The law mandates that crime begets punishment, and execution is seen by many as an appropriate (perhaps the ultimate) punishment.\n\nBy that logic, what legal punishment isn't revenge?",
"Case by case, I believe. For people in the category with Ted Bundy, who continued to be dangerous behind bars (he was highly intelligent and escaped) they must be given the ultimate sentence to protect the rest of us. Just my opinion. ",
"In the case of mass murder (Boston bombing), I view the death penalty as a way of getting rid of a crazy violent thing that fails at coming up with a civilized answer to the question \"Is there ever a good reason to randomly kill lots of people?\" \nAny mind that can't immediately answer \"no\" is a mind that can't be trusted to live among humans.",
"Revenge = getting even\nJustice = getting what you deserve\n\nThe two aren't really mutually exclusive, though.\n\nA not-so-accurate analogy: a bully picks on a fellow child at school. The victim child as a result does something back (assault, tampering, etc.) as a means of \"evening the square\" with the bully. However, the principle/school suspends the bully in addition.\nThe former would be \"revenge\" and the latter would be \"justice\".\n\nSide note: I've never heard the death penalty as \"revenge\". Am I out of the loop, or does the person decide the accused' fate instead of the state?",
"On a basic level if someone hits you then you hitting them back is justice, not revenge. This is one of those inalienable rights... When you become part of a society you give certain rights away to the society and allow it to take care of things for you instead. So, if in joining the society you have given up your right to hitting people who hit you and do it anyway you are now seeking revenge, not justice. \n\nSo in the case of the death penalty we have ceded to the society our right to kill someone as justice for them having killed someone else. Of course this all assumes a belief that eye for an eye is an inalienable right."
]
} | [] | [] | [
[],
[],
[],
[],
[]
] |
||
1jxdun | how does a game console know the difference between a retail disc and a burned disc? | Also what does a modchip do to overcome whatever protection there is? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1jxdun/eli5_how_does_a_game_console_know_the_difference/ | {
"a_id": [
"cbj7shx"
],
"score": [
2
],
"text": [
"A burned disc contains only the directly-readable digital content of the game. Retail discs contain other features - extra tracks not readable by most disc readers, specific wobble in the tracks, error correction codes that don't actually correct errors but instead contain authentication data.\n\nModchips will return a signal to the main CPU of the console that the disc authenticated as \"retail\", no matter if the disc contains the authentications features or not, when the CPU asks for the disc to be authenticated."
]
} | [] | [] | [
[]
] |
|
22lg36 | what does adrenaline do so that you don't feel the pain , such as from a knife wound or a gunshot? | English is not my mother language so sorry for the bad grammar. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/22lg36/eli5what_does_adrenaline_do_so_that_you_dont_feel/ | {
"a_id": [
"cgnye2o",
"cgnzorn"
],
"score": [
4,
3
],
"text": [
"It's been a while since I've taken endocrinology so someone can correct me if I'm wrong and add what I miss. Adrenaline causes a feedback loop of hormones that do things such as increase your heart rate and your reaction time. It primes you for movement (fight or flight, if you will). I'm sure that the same feedback loop tells your brain to stop processing pain so that you can escape from danger even if you've broken your ankle.",
"Pain is complicated, but a process called 'descending inhibition' occurs, where signals are sent from your brain down your spinal cord. These descending signals, mostly in the form of serotonin and noradrenaline, block pain signals that are traveling up different nerves in your spine, preventing them from reaching your brain."
]
} | [] | [] | [
[],
[]
] |
|
ev7puk | why is comedy less funny the more you watch it? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ev7puk/eli5_why_is_comedy_less_funny_the_more_you_watch/ | {
"a_id": [
"fftvdcd",
"fftvlb2",
"ffujk13"
],
"score": [
23,
4,
2
],
"text": [
"Comedy is probably best defined as the juxtaposition between the expected and the actual. For example, take the simple joke:\n\nTwo men walk into a bar, but neither one ducked.\n\nYou expected that \"bar\" meant \"drinking establishment\" but it actually meant \"metal rod\". The difference between what you expected and what was true is the humor.\n\nWhen you rewatch specials over and over, you are _expecting_ the punchline, so the expected = the actual and we no longer have the core element of humor.",
"What we find as funny changes over time. Comedians once joked about things that now we would find offensive. The comedy specials reflect the social atmosphere at the time.\n\nOld school Eddie Murphy isn’t as funny now as Amy Poehler stuff. It ages as time passes and our perspectives change. The more you watch it the more accustomed you are to it as well.\n\nMy two cents.",
"ELI5 - Your brain's a little knotted up.\n\nELI35 - Comedy, like all art forms, has a subjective element. Our perception of the world and each other changes as we go through life, and so does the way we react to things. Sounds like you let your sense of humor get a little stern. Or maybe your tastes changed and you need a different type of comedy. Later in life you may recollect all these things you feel like you're outgrowing now and realize again how much you really appreciate them."
]
} | [] | [] | [
[],
[],
[]
] |
|
bjqeob | why does online video (specifically youtube) get so insanely blurry at lower resolutions? why doesn’t the 240p option output a sharp and pixelated video? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bjqeob/eli5_why_does_online_video_specifically_youtube/ | {
"a_id": [
"emae92t"
],
"score": [
4
],
"text": [
"You could always use VLC to watch YouTube. Then you can go:\n\n Tools- > Preferences- > Video- > Show Settings- > All- > Video- > Filters- > Swscale\n\nAnd choose something like \"Nearest Neighbour\". I predict that you will quickly decide that this is worse to look at, unless the videos are of low-res video games or similar pixel art."
]
} | [] | [] | [
[]
] |
||
1owxbm | why do sister cellular companies such as simple mobile (t-mobile) exist, isn't that competition to themselves? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1owxbm/eli5why_do_sister_cellular_companies_such_as/ | {
"a_id": [
"ccwhzxn",
"ccwlbqz"
],
"score": [
2,
2
],
"text": [
"They aren't related at all. Companies like Simple Mobile have contracted with other companies, in this case T-Mobile, to sell their own service using the T-Mobile network. Simple mobile is MVNO service and has nothing to do with the actual service of T-Mobile. ",
"I think the best example is take Chrysler motor company in the 80s and 90s. They took these method to the extreme. You often had the same car under many different brands. Chrysler, Plymouth, Dodge for the same model, maybe even worse in some cases. You'll also see it in grocery stores where the more products you offer, the more shelf space you get. So lets say you are Company X, and Company Y, and you each make one type of cereal, and you are the only companies making cereal. Each of you would get 50% of the shelf space. Well, Company X decides it's going to make the same cereal and call it something else under a new brand, So then there is Company X and Z, owned by the same people, but getting 66% of the shelf space in this scenario.\n\nBasically, if you flood the market with more products, it drowns out the visibility to other companies. Also, less simply, you often want to attract different market segments and many companies find it easier to do this with different brands. Take, Toyota, Scion and Lexus. Same parent company, but hitting different consumer groups."
]
} | [] | [] | [
[],
[]
] |
||
1ofu2e | how does a grandfather clock work? | how do clocks that work off gears weights and pendulums work? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ofu2e/eli5_how_does_a_grandfather_clock_work/ | {
"a_id": [
"ccrk8ic"
],
"score": [
5
],
"text": [
"The weights provide the power to turn the gears that turn the hands on the clock. The pendulum is connected to this mechanism such that the gears/hands can't turn any faster than the pendulum allows. And a pendulum has a time to swing that depends on how long it is and how heavy the weight on it is. So it serves as the basic timekeeping device. \n \nThe key bit is the [escapement](_URL_0_). It allows the pendulum to control the turning of a gear. It also feeds a little bit of energy to the pendulum, overcoming whatever it loses through friction. "
]
} | [] | [] | [
[
"http://upload.wikimedia.org/wikipedia/commons/e/ee/Scappamento.gif"
]
] |
|
4hab0z | why do some all-organic, natural healthy etc. fruit juice drinks have 0% vitamin c? | And its not like the fruits in them have no vitamin C. So why is this?
| explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4hab0z/eli5why_do_some_allorganic_natural_healthy_etc/ | {
"a_id": [
"d2on71q",
"d2ord4d",
"d2orqww",
"d2oz8fl"
],
"score": [
7,
2,
2,
4
],
"text": [
"Grapes have very little vitamin C. But I am not aware of any case where the fruit *does* have plenty of vitamin C and then its juice *doesn't.* Can you please provide a link to such a product?",
"There is no government-mandated definition for the words \"natural\" or \"healthy\" on food packaging, so they can say whatever they want up to a point.\n\nOrganic does have a definition but refers more to the source of the ingredients, rather than the actual content of the ingredients. You could say you have organic ingredients in your fruit drink, but the only actual organically-sourced ingredient is a bit of grape juice in it, which wouldn't have much of any vitamin C.",
"It is possible that the Vitamins are damaged during the juice making process due to heating, or due to them being stored for a long period of time. Most vitamins can be conserved best when transported frozen. \nAlso some people say that 'cold-press' drinks don't damage the more sensitive parts of the drink (i.e antioxidants) but this could be nonsenses \n",
"There's no reason they should have Vitamin C unless the original fruit contains vitamin C.\n\nNatural=doesn't have much meaning. I could find a rotting cow on the ground and say that is \"natural.\" Doesn't mean I want to eat it.\n\nOrganic=means it is grown with no pesticides or a limited amount of pesticides that the government permits.\n\nNeither word has anything to do with how much/what vitamins something contains.\n"
]
} | [] | [] | [
[],
[],
[],
[]
] |
|
5hzytu | do wild animals know if humans are trying to help them (i.e. stuck sheep or trapped bear cubs)? | Like do they "feel grateful" that they were helped? Probably a dumb question but I always wanted to know. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5hzytu/eli5_do_wild_animals_know_if_humans_are_trying_to/ | {
"a_id": [
"db4afjx",
"db4bzjr",
"db4sx6h",
"db4yzyq"
],
"score": [
23,
69,
4,
7
],
"text": [
"It depends on the situation and on the animal. Sometimes the critter is so wound up they will go for anybody, so you have to dart them or cover them so they can't hurt you while you fix the situation. Other times they know they've tried everything they can and all they have left is trusting a stranger, regardless of species. Normally the wild ones will wait until they are out of danger, then make a break for it. If they are too tired they might need some time and care, but we try to give them space away from humans to get their heads together. Occasionally they will take their time on release, but mostly they just run for it.\n\nWhen it's most heartbreaking is when you have a domestic animal that is in such a bad way that when the Animal Welfare Officer turns up they just crawl into your arms and lick your face in the hopes you'll take them away. ",
"This is a difficult question to answer. Intelligence and cognitive abilities vary widely from one species to another. Each species' brain is different in terms of size, allocation of functions, etc. so we have to answer this question for each species individually.\n\nWhat it all comes down to is whether the animal in question possesses a [theory of mind](_URL_1_). This is the ability to attribute mental states to oneself as well as to others. Whether this is present in animals other than humans *at all*, and if so to what degree, is [hotly debated](_URL_0_). Research suggests some primates may have ToM at least to some degree, as well as some parrots and ravens.\n\nEven if an animal did have a theory of mind, that doesn't guarantee it makes the right assumption about your intentions. It might still come to the conclusion that you're going to catch and kill it like a predator would.\n\nSo when animals *do* decide to remain calm in such a situation, it's safe to assume they're so desperate or hurt that they've more or less given up already.\nAs far as pets go, at the vet for example: these animals recognize you as their master and as such are simply obeying you when keeping still.\n\nSo, do animals understand our intentions? Most likely: no.",
"The only way any human could really *know*, for certain, that animals are recognizing humans aiding them is if a human could actually get inside the mind, consciousness, of the animal - until then it's just theory and conjecture. Having said that though I'm sure animals with degrees of intelligence, especially social intelligence, like dolphins, cats, dogs, know on some level that humans are helping them in certain scenarios. ",
"Yes, at least the more intelligent do, since they sometimes actively seek help from people: _URL_1_\n\n_URL_0_"
]
} | [] | [] | [
[],
[
"https://en.wikipedia.org/wiki/Theory_of_mind_in_animals#In_nonhuman_primates",
"https://en.wikipedia.org/wiki/Theory_of_mind"
],
[],
[
"http://www.npr.org/sections/thesalt/2016/07/21/486471339/how-wild-birds-team-up-with-humans-to-guide-them-to-honey",
"http://www.telegraph.co.uk/news/2016/06/02/wounded-elephant-appears-to-plead-for-help-from-humans-after-bei/"
]
] |
|
13jr6u | realism (international relations) & the cold war | If possible, I'd like to learn the concept of realism (that is, the international relations theory) and **how it could be used as an approach to explain the Cold War.**
Likewise, what kinds of realist theories are there? What is the difference between **classical realism** and **neo-realism/structural realism**?
I would appreciate any information that could be simplified regarding this topic! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/13jr6u/eli5_realism_international_relations_the_cold_war/ | {
"a_id": [
"c74kh16",
"c74m0be",
"c74o547"
],
"score": [
3,
2,
18
],
"text": [
"It won't be much help with realism theory, but you might enjoy this series of international relations videos:\n\n[International Relations 101: Looking at international relations from a strategic perspective](_URL_0_)",
"Sounds a lot like a paper assignment...",
"Ok back to my old IR days, see if I can break this down..\n\nRealism -\n\nThe world is in anarchy, shit is fucked! I don't trust you, you don't trust me, we both certainly don't trust that weird looking dude over there. We basically don't have any rules because even if we did we certainly don't trust each other enough to follow them. The world is like a school yard and all the teachers are dead.\n\nNow how the fuck do we maintain order in this world of anarchy? Well we need power don't we. I don't want you to sucker punch me, and you don't want me to sucker punch you because if we start sucker punching each other there aint no teachers to come in and break this shit up! So what I do is start hitting the gym right, beef up, start lifting and building this muscle. Because If I am stronger than you, you aint going to try and fight me right? No you would have to be fucking crazy! But you on the other hand see me beefing up right, and you start thinking to yourself 'fuck this guy is getting strong, he can literally walk over here and kick my fucking ass, I better hit the gym to so I can hold my own in case shit hits the fan.' Ok this is called a **security dilema** We are both hitting the gym because we are fucking scared of each other and what we may do to each other so we are doing what we can to power up.\n\nNow what about the other kids on the play ground? They see us beefing up and they get a little scared too. But they might be a little yonger, they might not have access to good gyms for what ever reason, they don't want to beef up but they also don't want to be left alone on the playground because anything might happen to them. So these little punks start thinking about ways to befriend you or I so they get that little bit of security. This is called **band wagoning** We are essentially building alliances because, hey you might have bigger pecs than me, but me combined with this little dude over here might just be enough to take you on.\n\nOk now let's take this analogy and see if it makes sense in light of the cold war. There is no all powerful government (teachers) who controls what the world does, we have the newly formed UN but they don't really have an army and can't really do shit. World war 2 has just finished and the world is fairly unsettled and we have the United States (me) and the USSR (you) and we are assessing what the world (playground) is going to turn into. Now The US is a little insecure as they think the USSR might come and sucker punch them (Engage in warfare) so they start building up their military (hitting the gym). Now the USSR are like holly shit balls, the US are stocking up their military, we best do the same because no one else is going to come help us if they come over here and kick the shit out of us, so they start building up their military. Now we have that security dilema we were talking about, one states increased security measures cause another states insecurity which then makes them increase their security but indoing so decreases he security of the first state, in essence one big fucking circle jerk.\n\nOk so now we have the US and USSR building their military making more nukes and the other countries are all getting anxious so they start looking to bandwagon with either the US or USSR. So we essentially get NATO and the USSR gets the eastern bloc, China (for a little while) and several other states around asia and what not.\n\nI am getting tired now, so I will pretty much just leave it here. This is a brief eli5 rundown on the cold war. Hope it helps.\n\nIf you want to go into further detail like neo-realism, I encourage you to read the text book. Essentially neo-realism was created to explain the collapse of the USSR because classical realism couldn't.\n\nYou best upvote this, it took me like 10 minutes."
]
} | [] | [] | [
[
"https://www.youtube.com/playlist?list=PLB5965C13F4B0B2DA&feature=view_all"
],
[],
[]
] |
|
55bgcp | why are subtitles sometimes out of sync and progressively get worse? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/55bgcp/eli5_why_are_subtitles_sometimes_out_of_sync_and/ | {
"a_id": [
"d897i0w",
"d897mh0"
],
"score": [
4,
2
],
"text": [
"Its playing slightly slower than the movie, so the problem accumulates. When you pause, it resets because subtitles are usually linked to specific times in a movie.\n\nA decent free media player (like gomplayer, my go to) will usually allow you to speed them up a bit",
"Video is made up of a bunch of different images that change around 30 times per second. Historically, televisions always ran at the same speed. In North America, it was about 30 frames per second (NTSC), in Europe about 25 frames per second (PAL). This leads to certain problems when you're releasing the same movie between regions (to further complicate things, film projectors have been running at 24 frames per second pretty consistently since sound was added).\n\nOn modern (LCD/digital) televisions, there's no problem switching between framerates, so it doesn't really matter anymore if the video you're watching is from Europe or North America, but some videos are still 25 frames per second and some are still 30 frames per second. You have to dig pretty deep to actually find this information (if you have VLC installed, you can find this information in the codec information dialog).\n\nSubtitles, of course, need to be synchronized with the video. Every line in the subtitle has a reference for when it should be displayed, and when it should disappear again.\n\nIf you have video and subtitles that are correctly synchronized, and then remove the first second of video, every subtitle will appear one second later than it should. This is consistent though---the synchronization will not get worse throughout, it will always be one second off.\n\nSome subtitle formats use frame numbers as time references rather than minute/second/millisecond. Because this is what the decoder is dealing with internally, there is less processing required to handle the subtitles.\n\nSuppose a subtitle should be displayed after exactly five minutes. If the video is run at 25 frames per second, this means it should be displayed on frame 7500. But, if the video is run at 30 frames per second then this same spot in the video will be frame 9000 (1500 frame difference). At ten minutes, this is frame 15000 @25 or 180000 @30 (3000 frame difference)\n\nThis means that the subtitles taken from a European DVD will have different timing references than the same subtitles taken from a North American DVD. If you play a North American video with European subtitles (or vice versa), synchronization will be incorrect. It also means that the further you are into the video, the worse the synchronization will be.\n\nThere are tools that will recalculate frame references for subtitles (it's theoretically dead simple to do, but I don't have any experience actually doing it, so no software recommendations).\n\n---\n\nThe popular srt format stores timing information in minutes/seconds/milliseconds rather than frame references so it is immune to this problem. If you experience this with an srt subtitle track then most likely you just have poor subtitles."
]
} | [] | [] | [
[],
[]
] |
||
13y7fs | how true knowledge of future events have a bearing on the current ones? | I was talking to my nephew, while playing a game where you can stop and rewind time. He asked "Why can you do something different?" and I had no simple answer. How do I explain rewinding time to a six year old? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/13y7fs/elif_how_true_knowledge_of_future_events_have_a/ | {
"a_id": [
"c787j9e",
"c787r8e"
],
"score": [
3,
4
],
"text": [
"The same way that you can shoot fireballs by touching a flower. Because the game allows you to do something different.",
"[Here's Martin Gardner's kid-friendly introduction to time travel and the paradoxes it creates.](_URL_0_)\n\nStart on the linked pages, and read through the following pages to an appropriate level for your six year old."
]
} | [] | [] | [
[],
[
"http://books.google.com/books?id=UNfWR8tGp4wC&lpg=PA150&ots=M25-u67ZbK&pg=PA150#v=twopage&q&f=false"
]
] |
|
7klu30 | probably a dumb question but here goes. if someone has lice why exactly can't they just dip their head in water and drown the lice? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7klu30/eli5_probably_a_dumb_question_but_here_goes_if/ | {
"a_id": [
"drfatfc",
"drfaw0j",
"drfaw2n"
],
"score": [
5,
7,
14
],
"text": [
"It'd be hard to drown lice. But I think it's a good question.\n\n*Research has shown lice can survive when immersed in water for 14 hours at 86–98°F.*\n\nsource: google search",
"because lice can survive underwater for up to to 14 hours. so unless yer staying underwater with scuba for that long.....",
"Lice can survive a long time underwater, about 14 hours. I would imagine that their eggs would survive and repopulate as well. So perhaps you could drown them, but you'd have to drown yourself first. "
]
} | [] | [] | [
[],
[],
[]
] |
Subsets and Splits
No saved queries yet
Save your SQL queries to embed, download, and access them later. Queries will appear here once saved.