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|---|---|---|---|---|---|---|---|---|---|---|
ep193y
|
How come no matter how much water I pour in the toilet, the water level never rises?
|
Engineering
|
explainlikeimfive
|
[
"fegdkcw",
"fegdn26",
"feh289l",
"feh0lc8",
"fegtgl9"
] |
[
"There's a U-bend just past the hole where the flushed water goes. The water goes from the bowl backwards, up a bit, and then straight down to the drain. That's the U-bend. As you pour water into the toilet the water level in the bowl rises, but also on the U-bend side. The water goes over the edge of the bend and the water drains our keeping it in balance."
] |
[
55
] |
[
[],
[],
[
"http://www.renovation-headquarters.com/images2/toilet%20diagram.jpg"
],
[
"https://www.amazon.com/Toilet-How-Works-David-Macaulay/dp/1626722153/ref=sr_1_12?keywords=Toilet&qid=1579106531&s=books&sr=1-12"
],
[]
] |
[
"url"
] |
[
"url"
] |
|
dg5xah
|
on yawning - what does the intake/outtake of breath have to do with being tired?
|
Biology
|
explainlikeimfive
|
[
"f39zyjd"
] |
[
"I think it has to do with the need for quick delivery of oxygen to the brain. Yawning facilitates that. I'm really just here to comment and tell you that the title of your post made me yawn."
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
5y2yb2
|
How does radiation affect electronic machines? Robots being sent to the Fukushima disaster site keep being messed up. I know it affects humans by damaging our DNA, but how can it damage electronics the same way?
|
Physics
|
explainlikeimfive
|
[
"demqrd2",
"demx2bs"
] |
[
"Materials becomes brittle, magnetic fields are generated which can cause voltage to jump between parts on integrated circuit boards or wipe magnetic media, bits can be flipped which can corrupt the memory in solid state components, etc."
] |
[
6
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
b9cjxm
|
Why sugary liquids are sticky when "dry"?
|
If you drop soda on your hands or eat sugary treats they get all sticky/gluey even after they're "dry".
|
Chemistry
|
explainlikeimfive
|
[
"ek3nw1x"
] |
[
"Sugar is really good at holding onto water (both are polar & together they form a matrix), so the stickiness is because it’s not totally “dry”"
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
a57t0v
|
What's the difference between exothermic/endothermic and exergonic/endergonic?
|
Physics
|
explainlikeimfive
|
[
"ebkilb2"
] |
[
"An exothermic reaction results in a positive transfer of heat, while an endothermic reaction causes a negative transfer of heat. An exergonic reaction causes a net increase in free energy, while a endergonic reaction causes a net decrease in free energy. What's the difference between heat and free energy? Heat is energy transferred during a reaction. Thus, you could think of an exothermic reaction as \"releasing energy\" and an endothermic reaction as \"absorbing energy.\" Free energy is *all* of the energy that a system has to do work with. It includes the enthalpy of the system, but also is involved with the entropy. So a reaction can be exothermic and endergonic if it increase enthalpy but decreases entropy. A reaction can be endothermic and exergonic if it decreases enthalpy but increases entropy."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
5xdszm
|
Why does drinking alcohol when hungover make you feel better?
|
Biology
|
explainlikeimfive
|
[
"dehatyz",
"dehm1xe"
] |
[
"for much the same reason as it made you feel good the first time. The dehydration and other hangover symptoms are still there, but the new rush of alcohol numbs you the same way it did the night before."
] |
[
14
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
679r40
|
How do we know that a machine isn't deceiving us during a Turing test by simulating detectable machine answers so the AI remains undetected?
|
Technology
|
explainlikeimfive
|
[
"dgoqfip",
"dgp3gj5"
] |
[
"Theoretically it's possible that someday there could be an intelligent machine that tried to hide its own intelligence. Today we know that's not the case because we understand how all of the machines that have ever competed in Turing tests actually work. They're all designed to fool an unsuspecting human for a few minutes or otherwise say human-like things, but not to have real intelligence."
] |
[
9
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
aupioy
|
If we can't get under 7nm with silicon why are intel/AMD not building bigger dies with more transistor instead of always shrinking?
|
If a regular CPU consume 95W today in 14nm, why aren't they building HUGE cpu that consume 3-400 watts? all we would have to do is having a bigger PSU and more efficient cooling.
|
Technology
|
explainlikeimfive
|
[
"eh9n6s2",
"eh9nb9p",
"eh9n59h"
] |
[
"> why aren't they building HUGE cpu that consume 3-400 watts? all we would have to do is having a bigger PSU and more efficient cooling. Because it will generate a metric ton of heat. Like, a lot. Which means a big ol' heatsink and a noisy, high RPM fan. Your power user might use liquid cooling to make this more efficient (which would also mean using larger fans which mean lower RPMs for the same airflow which means more quiet) but this isn't practical for Joe Consumer or Joe Business User. Furthermore - did I mention it will generate a ton of heat? Using a processor that was 125W stock and close to 200W overclocked in a ~10-14' bedroom that would normally be 68 degrees in winter, in a few hours it would heat the room up to about 78 degrees and I'd have to open my window in the dead of winter. Now try generating 2-3 times as much heat. Oof. Also, energy isn't free. An extra 305 watts for 8 hours a day is 890.6kWh in a year. The average price americans pay per kWh is 12 cents, which means you're spending an extra $106.87 a year on energy. Finally.... Why NOT continue to reduce die size until we've hit practical limits? More efficient means you can get the same performance for less heat/power... Which means you can get even MORE performance if you overclock it a bit."
] |
[
26
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
6cz92q
|
How do you go from a country that drives on the left side of the road to one that drives on the right?
|
Other
|
explainlikeimfive
|
[
"dhyjm3x"
] |
[
"There are surprisingly few land borders on Earth where right-hand-drive countries meet left-hand-drive ones. Most of the remaining major drive-on-the-left countries (Britain, Japan, Australia) are islands, so the border problem doesn’t really come up. Other major exceptions (southeast Africa, the nations that were once British India) come in clusters that mostly border each other. There are a few nations that do have to worry about how to switch traffic at the border. Left-driving Thailand is one; all four of its neighbors drive on the right. Most of its high-traffic borders just use a traffic light to alternate the flow of vehicles. But there are more elegant arrangements, ones that allow for continuous traffic—such as the [bridges of Macau.]( URL_0 )"
] |
[
7
] |
[
[
"https://media.cntraveler.com/photos/53d9d5dd6dec627b149da425/master/w_650,c_limit/lotus-bridge-macau-google-earth.jpg"
]
] |
[
"url"
] |
[
"url"
] |
|
atwrnl
|
Why is palm oil in everything? What is it's purpose?
|
Biology
|
explainlikeimfive
|
[
"eh3xlt4",
"eh3ymc2",
"eh3you7"
] |
[
"It extends the expiration time. It's used a lot in cosmetics for that,but you should avoid it in foods."
] |
[
6
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
iyvbrk
|
Why do we say "Human Race" despite Humans are not a race, but a species?
|
Biology
|
explainlikeimfive
|
[
"g6evoqu",
"g6evl56",
"g6evopz"
] |
[
"The word \"race\", interpreted to mean an identifiable group of people who share a common descent, was introduced into English in about 1580, from the Old French rasse (1512), from Italian razza. Source: URL_0"
] |
[
10
] |
[
[
"https://en.wikipedia.org/wiki/Historical_race_concepts?wprov=sfla1"
],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
mb0jqn
|
How do the game servers and game clients communicate with one another in online games?
|
I was wondering earlier if you shoot a bullet in a game, how does the other person take damage? What kind of things are updated between a server and client? What about team games? Lets say I am on blue team, and the other team is the red team, who manages the spawn locations, the server or the client?
|
Technology
|
explainlikeimfive
|
[
"grvhe2g"
] |
[
"For the purposes of this post, I'll use your example of a multiplayer shooter game. The simpler part of the question is the spawning positions: typically, that would be the server's job but there is no technical aspect why that wouldn't be done in the client (other than to curb cheating, but that kind of cheat is typically trivial to detect server-side). As for the rest of the question: because of the time it takes for a message to get from client to server (and vice versa), the server and each game client actually have slightly different game states. That is to say, the game you're seeing is, in fact, *slightly different than what it actually is*, because the server is the source of truth for what happens in the game (read: whatever the server says, goes). Every client is a little bit late to the party, so what you see on your screen has actually already happened (i.e., you're playing in the past). Each individual update from the server to client (and from client to server) is sent via packets, which you can think of as boxes containing tidbits of information, going either direction. How often these updates are sent by the server and the client in shooters is what is referred to as \"tick rate\". So, in a 128 tick server - that's *ticks per second* \\- you'll get and send updates 128 times a second. In figuring out how to display an accurate game state, the client actually has to do some guessing (how exactly that's done is fairly complicated) because displaying an exactly correct game state would require zero network latency, which is (physically) impossible. Another aspect of this is to answer the million dollar question: who shot first? In CS:GO, for example, the server does what is called \"latency compensation\". To simplify, the server takes into account the time that it takes for it to receive a message from clients 1 and 2 (the two players shooting at each other), and factors that when calculating the real time either shot was fired. That's also why there is a peeker's advantage: what you're seeing has already happened, *unless you're doing it yourself* (in which case, you're on time and *everyone else is late*). Since the other guy sees you later than you see him, you get a few extra milliseconds to take his head off before he does the same to you. & #x200B; TL;DR: the server is typically the source of truth in a multiplayer game (and *should always be*), but the client holds a game state to be shown to the player. The client receives inputs, processes them, and simultaneously shows them on the screen and sends them to the server, which processes them, updates its own game state, and sends updates to the other clients). & #x200B; edit: if you wanna read more, the folks over at Riot have a *great* writeup of how a lot of this works (jsyk: it gets technical). I highly recommend this one, it's a great read: [ URL_0 ]( URL_0 )"
] |
[
3
] |
[
[
"https://technology.riotgames.com/news/peeking-valorants-netcode"
]
] |
[
"url"
] |
[
"url"
] |
le3692
|
Why does old news footage from the 20th century all sound the same?
|
For example: URL_0 URL_1
|
Technology
|
explainlikeimfive
|
[
"gm95y77",
"gm95bj2"
] |
[
"What you are looking at is not news as we know it today but rather movie news. They are short movies made about current events and then distributed to the cinemas to be shown to a paying audience. People would visit the cinema to watch these reals maybe once a week. Most of the times they read the news in the newspaper or listens to the radio. But for moving high quality images of what was happening you had to go to the cinema. There is a few limits to making films in the early days and due to time and budget constraints the movie news were often some of the last places you had these limits. For example color cameras and film were much more expensive and cumbersome to work with then black and white films. So movie news were often black and white even when it had become common for the big Hollywood studios to make color films. Similarly sound was hard to work with so they often just dropped it. One problem was to collect and sync clean sound as you were filming but not all cinemas were able to play sound movies either. So the sound were usually made in the old silent movie style with a script for someone to read live to the audience and maybe some notes for an organist. The movies might have a sound track that included this voiceover and the music but could still be played on older equipment."
] |
[
5
] |
[
[],
[
"https://www.theatlantic.com/national/archive/2015/06/that-weirdo-announcer-voice-accent-where-it-came-from-and-why-it-went-away/395141/"
]
] |
[
"url"
] |
[
"url"
] |
70gl2z
|
How can I go from feeling fine at 11am to sick with a high fever at 12pm an hour later? Do viruses/bacteria really work that fast?
|
Biology
|
explainlikeimfive
|
[
"dn31y09"
] |
[
"It is not the the bacteria or virus causing the fever, it is the body reacting tot it. And yeah, your body is really fast when it comes tot fighting potential disease."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
817ylg
|
Why does drinking coffee occasionally make me more tired?
|
I drink coffee regularly, typically 2-3 cups/day. I've noticed that sometimes when I'm already fading (usually mid-PM) immediately after I drink another cup, I crash. ELI5?
|
Biology
|
explainlikeimfive
|
[
"dv1dc9r"
] |
[
"Simple answer: Caffeine doesn’t give you more energy, it stops you from becoming tired. So if you’re already tired by the time you drink your caffeine, it won’t really do much. Long answer: caffeine binds to adenosine receptors. Adenosine is the chemical that your brain produces to make you tired when it’s time to go to sleep. When caffeine binds to an adenosine receptor, it prevents adenosine from binding and thus prevents you from getting tired. So, if your brain has absorbed a lot of adenosine, you’ll be tired. Any caffeine you consume after you’re already tired will take a while to work because it’s only blocking NEW adenosine from being absorbed, not removing adenosine that has already be absorbed."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
8s11vb
|
Why does medicine have unnecessarily large packaging?
|
Other
|
explainlikeimfive
|
[
"e0vnxy9",
"e0vqips",
"e0vqfmq"
] |
[
"1. It's expensive which gives people a motivation to try to steal it. And it's small which makes it easy to hide in a purse or pocket. Big packaging reduces theft. 2. More surface area for writing information. 3. Layers of packaging make tampering harder."
] |
[
15
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
dtvnm2
|
What part of the eye does an eye scanner scan and register?
|
Technology
|
explainlikeimfive
|
[
"f6zt3ma"
] |
[
"^(typically the iris-- which is the colored bit around the pupil. there are lots of ridges and variabilities in the surface which makes it unique to the person like a fingerprint.)"
] |
[
12
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
8pej5j
|
How do water bubbles form just underneath the topsoil like lawn pimples?
|
Chemistry
|
explainlikeimfive
|
[
"e0az4hi"
] |
[
"Usually this happens in a place that had sod lay down on top of aoil that poorly drains and the roots havent penetrated. The water goes easily through the sod but gets stuck by the clay etc. Its a thing that you do not want to happen and is showing a failure of the sod and maybe overwatering."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
8ipzc4
|
What is bruteforcing?
|
Technology
|
explainlikeimfive
|
[
"dyto4af",
"dytobhg",
"dytq9a9"
] |
[
"Trying every single possible combination until you get it right. It's why websites are now forcing you to use special characters, numbers, AND caps in passwords. It makes that many more possible combinations so bruteforcing is harder."
] |
[
14
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
bwvkhh
|
why are there so many ways to measure radioactivity, like Röntgen, Becquerel and sievert
|
Physics
|
explainlikeimfive
|
[
"eq0pmfe",
"eq0p1q7",
"eq1ne8n"
] |
[
"Some are antiquated units, but there are also very different sorts of measurements made. You can measure total energy, the biological effect depending on tissue, or total decays. There are a bunch of antiquated units still used, but many units are measuring different effects. Becquerel is measuring decays per second, and is the most fundamental, sievert is based upon biological impact, and gray is based on total exposure. Most have alternative units as well."
] |
[
13
] |
[
[],
[
"https://www.remm.nlm.gov/radmeasurement.htm"
],
[]
] |
[
"url"
] |
[
"url"
] |
|
6ylfkx
|
How do obviously fake facebook profiles sending me a friend request end up making money for the people who make them?
|
Other
|
explainlikeimfive
|
[
"dmoalbr"
] |
[
"I assume you're talking about the fake \"super attractive girl in revealing clothing\" profile. Most of the time these are run either by webcam girls as advertisement for their own show, or by bots run by the webcam site itself, as advertisement for the site. The girl makes money from you entering a private show with her, and the site gets a cut. The girls prey on younger or technologically illiterate people. It makes it seem more legitimate to have someone on FB send you a friend request, rather than a spam email from Jazmine. They chat you up, get you hooked, give you the link, and take it from there."
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
7gxiuc
|
what is crypto currency? How is it used and where does the money actually go??
|
Economics
|
explainlikeimfive
|
[
"dqmkzbx"
] |
[
"Basically, instead of having a server that says, Person X has $52, person Z has $3000, they work by giving everyone a copy of the data. The data from the past in included in future transaction logs (called Blocks generally) in such a way that confirms that the new transactions are valid. I'm not gonna get into mining, since it differs between crypto variants, in terms both of what needs to be solved and how new coins are distributed. I assume you are asking because the price of Bitcoin is skyrocketing. The way that they are valued is based on trading. Someone says I want to buy 0.25 bitcoins for $X, and if someone else has said they want to sell for $X, than a transaction occurs. So anyone getting money *out* of the system comes from someone else putting money *into* the system. There are many websites that exist to do this process, and they work off of the main transaction archive (not on the Blockchain). This is because it is both much, much quicker and cheaper to do so. You send X bitcoins and $Y to an exchange, and now they track that on your account. So we're back to where we were with normal currency systems, as opposed to distributed. There are a lot of things that go into why the price is rising, why prices tend to be pretty equal across multiple exchanges, but this already getting a bit long."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
6j3y5j
|
What started/caused the Vietnam war, and was Vietnam equipped enough to have concocted and dispersed agent orange?
|
I currently live in Turkey and there have been some bans on some websites (such as Wikipedia) leaving me with limited resources for research, so I thought who better to ask than my fellow redditers.
|
Other
|
explainlikeimfive
|
[
"djbcm24",
"djblv9q"
] |
[
"1. US dispersed the Agent Orange, not the Vietnamese. 2. We started the war with a glass flag attack in the Gulf of Tonkin, giving us an excuse to invade the country out of fears the pro-communist faction fighting against the democratic faction may win."
] |
[
6
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
8y4dd6
|
Why is there such a thing as ‘check-in’ when flying?
|
Why can’t I simply receive my ticket (boarding pass) when I book a flight, like I would with every other means if transport?
|
Economics
|
explainlikeimfive
|
[
"e281riv",
"e2813dm"
] |
[
"The airlines want to be able to fill every seat. If they make a rule that says you have to check in, and people don't check in, they'll sell your seat so that the plane stays full. It's more profitable for them to do this."
] |
[
10
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
72togi
|
With all these posts about mental health problems and abusive relationships: Is human mental health innate/hereditary, social constructs, or a combination of both?
|
Biology
|
explainlikeimfive
|
[
"dnl6a3l"
] |
[
"Stress can certainly bring out some mental health issues. So can living in a more crowded society even if all your needs are met. A while ago a man named John B Calhoun did an experiment on mice. The experiment was called Universe 25. In the experiment he had mice living in an environment in which all there needs were met. They had food, water, and health care! They were allowed to breed uncontrolled so their numbers climbed. Even though they always had enough food to eat, the mice started showing signs of mental health issues as they became more and more populated. The mouse equivalent of rapes became more common, mother mice started becoming shitty mothers, fights broke out even though there was no reason for them (random acts of violence). Soon things got even worse and the mice stopped behaving like mice (behavioral sink) and stopped breeding altogether. Even as they started dying off and numbers shrank, they never acted normal again. He did the same experiment in rats and saw the same thing, except that as the rats started dying off and their numbers got lower they did start behaving somewhat normal again. So.. in our society of 7.7+ billion people (noting that our population has more than doubled in the past 40 years alone and that for thousands of years our population was less than only a billion people) it's clear to see that some of the mental problems are likely the result of us feeling like nothing, like nobody, like one in 7+ billion people.. we lose compassion for others as well in such a society."
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
icug96
|
How do companies not run out of stocks?
|
So I get the super super basic parts of stocks, but I don't really get how a company doesn't run out of stocks. I assume that there has to be some limit to the amount of shares a company has, since otherwise they could just keep adding more and it would make existing shares worth less - is that assumption accurate? If the above is accurate, then how does a company not run out of shares, especially if stock options are included in their employee contracts? I guess a basic example might help. Company X has 10,000 shares. The 3 founders each have 2K shares, so there are 4K left. They've hired 1,000 employees so far, and each are given 2 stock options (so 2,000 are left). Assuming that they want to keep hiring people and giving them stock options, can they only hire 1,000 more employees if they want to give them 2 stock options each? If they want to hire 4,000 more employees and give them each some stock, could they only give each employee half a stock (if that's even a thing?). And once they go public, can they add more shares or is that that? Is there ever a time when someone wants to buy stock in a company but it's like 'sorry, all the shares are taken'?
|
Economics
|
explainlikeimfive
|
[
"g24vdeg"
] |
[
"You're asking a wrong question, sorta When a company goes public, ALL (*some exceptions) of its stock is public to be bought or sold. Any owner of any individual share can choose what to do with their share, they could sell it or not. That is, all shares of public company are always \"taken\" to use your language. Really it means that the company is 100% owned by its owners, that is all shares are owned. So yes, thats all the stock thats out there! Thats it. OK, but not really, technically at any point a company can issue more shares and this is common. The most common thing is for giving stock grants to employees, instead of buying shares on the open market to give to employees, they just issue them new shares. And yes, the stock price of the company will be effected by this. the overall value of the company didn't change, so with more stock in the market, then each share is worth a little less."
] |
[
7
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
64uuwj
|
Why, when on a low calorie diet, does your body consume muscle as well as fat? Why not just fat?
|
Biology
|
explainlikeimfive
|
[
"dg56t52",
"dg5ejl5",
"dg59pdq"
] |
[
"Extra muscle is a luxury. Your body wants to be strong, but the more muscle it has, the more food it requires. If it thinks there isn't enough food available, it reduces the amount of muscle you have so you will use less in the long run."
] |
[
16
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
8vr28x
|
Why Will it Take Months to Rescue the Thai Boys Trapped in a Cave?
|
Engineering
|
explainlikeimfive
|
[
"e1pkoy0"
] |
[
"Waters have risen since they entered the cave, as such they need to scuba dive out. The dive is so perilous in its flooded condition that only special rescue divers have traversed it so far. So you essentially need to train 11 year olds to dive and then line up specialist divers to accompany them. You could probably do one dive per day with one child once they are actually trained."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
dcs87a
|
Why are some artwork sold for millions that look like some child splashed colors at random on a canvas?
|
Other
|
explainlikeimfive
|
[
"f2apk7b",
"f2ap95n",
"f2apsm9"
] |
[
"Because the art world is mostly a confidence trick game, where everything is based upon the reputation and not the quality of the artwork. Finding out a piece of art was not done by the highly rated artist can slash the price of it without the art work changing one bit. A million dollar selling artist is basically only that because someone was prepared to pay that for it and hopes later to sell it on for more."
] |
[
5
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
evasmw
|
why does background music prevent deep sleep?
|
I’m reading a baby sleep training book and it says that music will prevent deep sleep after four months old. Why is that?
|
Biology
|
explainlikeimfive
|
[
"ffujozg",
"ffulzku"
] |
[
"When your asleep, your body runs a delicate balance between cutting itself off from the world so it can sleep, and being aware of it just enough to keep itself safe if need be. Music can help block out thoughts and other noises to help you fall asleep, but, as the track changes to a different song, or even as one song moves to a different part, you can register a sudden change in your environment, bringing you out of your deep sleep to check it out. This can disrupt your regular rhythm and make sleeping more difficult and less restful."
] |
[
40
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
m598b8
|
Why is it that when new video game consoles/devices launch they always run out of supply?
|
Ever since I can remember new consoles run out of stock. Xbox, Playstation, Switch...I want to believe that these companies use forecasting like every other type of business but why does the supply chain always fail?
|
Other
|
explainlikeimfive
|
[
"gqytiqc",
"gqytp5g",
"gqzezhs"
] |
[
"First: They underestimate the demand. Second: A perceived or reported shortage spurs more buyers. Third: They are ramping up production. Fourth: Sheer cussedness."
] |
[
20
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
gjq9ds
|
Why do so many businesses demand deliveries between 6am and 10am?
|
Economics
|
explainlikeimfive
|
[
"fqmee4o"
] |
[
"Usually those are slow times for customer traffic for retail-type businesses. So they can get a delivery without the truck eating up parking space and/or taking employees off the floor to deal with it."
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
71qr7e
|
Why is CTE brain damage such a hot topic in the NFL, but don't hear anything from the Rugby community?
|
Other
|
explainlikeimfive
|
[
"dncp5pe",
"dncw0lk",
"dnd3tm0",
"dnczxjh",
"dncu6dz",
"dncrxy5",
"dncopbk",
"dnd6ycy",
"dndja4d",
"dncoykc",
"dndfxvd",
"dncye53",
"dncu67n",
"dnd0riy",
"dnd9k9k",
"dndq7mn",
"dnd34dh",
"dndkklk"
] |
[
"While people often think of the gigantic, brutal head to head hits when they think of CTE, a huge part of the risk is just the every-play blocking and the fact that if you go from moving fast to a dead stop, your brain can smack against your skull. Because of the increased padding and increased rest time (time between plays and not playing both offense/defense), there is far more emphasis on explosiveness, strength, and speed relative to endurance in American football. You're not going to get a 4-5 300+ pound guys in rugby because they just can't keep up all game, but their 40 times are absolutely incredible for their size. So you've got everyone hitting everyone on every play, and they can put more force behind each hit because they're better rested. Additionally, the combination of helmets and the 10-yard first down rules means that the rugby wrap-up style tackling might not always be the most effective if they fall forward another 2-3 yards"
] |
[
1392
] |
[
[],
[],
[],
[],
[],
[],
[],
[
"http://www.bbc.com/news/world-australia-37335540",
"http://metro.co.uk/2017/07/12/rugby-player-14-dies-on-pitch-after-suffering-head-injury-6772537/",
"https://www.ncbi.nlm.nih.gov/pubmed/26786902"
],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
couixt
|
How do you explain average to My 5 year old kid?
|
Hi I want to explain my kid about the concept of average it seems very common but hard to explain.
|
Mathematics
|
explainlikeimfive
|
[
"ewlaytx",
"ewld8np",
"ewlae4l",
"ewlcu4r"
] |
[
"Let’s say you had three friends come over, and you knew they were all bringing you some sweets for your birthday. Your first friend gives you 3 sweets. Your second friend gives you 5 sweets. How many sweets might you expect to get from your third friend? An ‘average’ is the expected value for an event, in this case ‘giving sweets.’ Since you saw one person give 3, and one person give 5. You can calculate the expected value by adding them all up (8), and dividing by the number of people (2), to say the average is 4. You now know you expect 4 sweets ... but it doesn’t mean you will get that many. After you find out how many you do get, you could calculate the new average from three people to get a better idea of what to expect if a forth friend turned up with sweets to give you."
] |
[
12
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
e1k8pc
|
How can we be certain that the maths we use is correct?
|
This might seem like a stupid question but I just don’t understand how we know for a fact that the maths we use is actually accurate if all numerical figures were just thought up? Aren’t 1, 2, 3 etc. just random lines and curves?
|
Mathematics
|
explainlikeimfive
|
[
"f8q63v0",
"f8ptc7s",
"f8qahdo",
"f8psr7b",
"f8pxu37",
"f8psw8j",
"f8ql061",
"f8qkeax",
"f8q7c9o"
] |
[
"TLDR; It is correct because we say it is correct. We keep using it because it is good at what it does. **This is not a stupid question**. This is in fact one of the most profound questions ever asked and humanity may never know the answer to it. Math is a language used to convey relationships like one thing is the same as another thing. It is one of the most beautiful languages every made because it is based on some simple statements called **Axioms**. An axiom is something that is true because we say it is. There is no other requirement needed. Let's play with some axioms and do non-mathy versions too: ||Mathy Version|Non-mathy Version| |:-|:-|:-| |Reflexive Axiom|a = a|The color of the sky is the color of the sky| |Symmetric Axiom|a = b therefore b = a|The color of the sky is blue so blue is the color of the sky.| |Transitive Axiom|a = b, b = c therefore a = c|The color of the sky is blue and my shoes are blue. Therefore my shoes are the color of the sky.| There isn't any universal truth in any of those statements. We could say that the color of the sky is red, taupe, banana, or florg and the statements are all still true only because we say they are. The assumption may be wrong (the sky obviously is not banana) but we say it is true so it is true. You can make any axioms you want but if they don't do a good job at describing things then it'll be hard to get other people to use them. All of math is based around a few axioms. The amazing thing is that these simple things we say are true, allow us to perfectly describe the universe with such amazing precision that we have to ask is the universe made of math or do we make math to describe the universe."
] |
[
290
] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
o527rl
|
- I collected seeds from my black petunia and the resulting flowers were shades of green, yellow, pink, white, purple, black, and striped . How?
|
[a picture of the flowers]( URL_0 )
|
Biology
|
explainlikeimfive
|
[
"h2keaa2"
] |
[
"The petunias sold as plants are hybrids of petunia between P. axillaris and P. integrifolia. These hybrids don't breed true to form, like many plants."
] |
[
7
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
5owy9a
|
Why does SpaceX land their rocket on a barge on the ocean?
|
Why not land on flat, stable land?
|
Engineering
|
explainlikeimfive
|
[
"dcmni12",
"dcmqir2",
"dcmrdyg"
] |
[
"Because landing on land limits the places you can take off from and the direction you can point your rocket. I believe the first successful test of the rockets did have them go on land, but the goal is to let the rockets take off in the most efficient places to put their payloads into orbit. If that means taking off over the ocean, then they need to have a landing spot on the ocean."
] |
[
20
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
96ncu9
|
Where is my oil going when it gets low?
|
Where does the oil in your car go when it gets low? I thought it’s a closed system, so it can’t get out. But how does it burn off?
|
Engineering
|
explainlikeimfive
|
[
"e41re35"
] |
[
"Leakage into the combustion chamber either by ill fitting rings or leaking valve seals. Once in the combustion chamber it is burned off similar to the way the gasoline burns."
] |
[
23
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
9bzwp8
|
Why dont front windscreens of cars have defogger lines like the rear window?
|
Engineering
|
explainlikeimfive
|
[
"e577o5n",
"e5781ui",
"e579mi3"
] |
[
"I'm not sure if I'm misunderstanding all the answers here, but a lot of cars absolutely **do** have defogger lines in the front window. They're just made to be a lot finer and are normally vertical so, sure, they don't distract, but also so you don't get the horizontal bands of gradually widening visibility when you switch on, it clears things a lot more evenly and quickly. [Here's]( URL_0 ) what a heated windscreen grid looks like close up."
] |
[
7
] |
[
[
"https://www.safelite.com/images/default-source/default-album/[email protected]?sfvrsn=993c1609_0"
],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
da9i9a
|
why are rainbows curved?
|
Other
|
explainlikeimfive
|
[
"f1o3xsx"
] |
[
"A rainbow is what you see when tons of teeny water drops refract or bend light back at you. Different wavelengths or colors of light bend at different angles because they travel in water at different speeds. With the sun behind you and rain or mist in front of you, these drops bend the circular boarder of the round sun back to you. A full rainbow is actually a circle for this reason! In short, you're basically seeing an outline of the round sun bent back at you and split into a bunch of colors!"
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
9kq6vs
|
How can sites, such as URL_0 , accurately trace your family history?
|
Biology
|
explainlikeimfive
|
[
"e70whsr",
"e70wkrb"
] |
[
"By and large it depends on various public records, and contributions from customers. These can be inaccurate."
] |
[
5
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
i5ymsw
|
Living in the desert of Las Vegas and work I g in a casino that separates food waste from plastics and other wastes; I often wonder if the food waste in high amounts could give life to the soil or would it just be a biohazard to try to mix it into the earth to bring back nutrients.
|
Was wondering if deep trenches where filled out in the desert with food bio-waste. Could we perform small scale terra-forming? Would it just end up creating a mess. Kinda wonder of we could even bank away useable biomass in the deserts even.
|
Other
|
explainlikeimfive
|
[
"g0seu6m",
"g0sa6w0"
] |
[
"Most of the casino food waste in Las Vegas goes to the pig farms. There was a sad news story during the shut down about the farms not being able to support the pigs anymore. & #x200B; Edit: [ URL_0 ]( URL_0 )"
] |
[
9
] |
[
[
"https://www.foxnews.com/us/las-vegas-pig-farm-food-scraps-casinos-coronavirus-pandemic"
],
[]
] |
[
"url"
] |
[
"url"
] |
8gva0o
|
How come when it’s hot out, and your turn your AC on to say, 68 degrees, it feels good.. but when it’s cooler outside, and the AC is still on 68 degrees, you feel cold even though the temperature in the house has been regulated?
|
Repost
|
explainlikeimfive
|
[
"dyey38o"
] |
[
"It has to do with the humidity. When it's hot, the humidity is usually higher, making your body work harder to regulate it's temperature by trying to cool. Turning in the AC removes some humidity from the air, making it easier to be cool. When it's cold, the humidity is usually lower, making it easier for your body to cool itself. In these cases, you body then tries to wash itself."
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
5vs3tl
|
Why does the U.S government own most of it debt?
|
Why does the government loan itself money. If program __x__ has a surplus and buys bonds to fund program __y__, why wouldn't they just balance the budget so both programs get what they need?
|
Economics
|
explainlikeimfive
|
[
"de4e9xm"
] |
[
"This isn't a complete answer, but it might help. A big organizations isn't like a house hold. At home, you're in charge of your budget, and it's up to you to give money from eating budget to the home improvement budget if you need to buy a new lamp for example. You hold all the power, so you can take and give as you want (assuming you're not married that is). On the other hand, power in any big organization is distributed between different people. In the government, this separation is setup by law. They don't want any one part to become too strong. So, now you have a bunch of people with some power. And, money is simply another form of power. So, the guy running the FBI has power (and money), as does the guy running the EPA. **As far as I know, this isn't a real situation** Let's say the EPA needs money, and the FBI has money. Now, if the FBI just gives the EPA $100,000,000, they lose the Power that money brings. On the other hand, if they were to buy bonds from the EPA, they would just be loaning that power, with the promises of getting it back + more in interest. Now, that answers the reasons why someone doesn't transfer the money. But, since the FBI and EPA don't actually fund themselves this way, it doesn't say why the government owns bonds. As far as I know, it's mostly the Feds and the Social security administration who hold Treasury bonds. But, local government savings funds / wealth funds also hold bonds. And, they all do so for different reasons, each would take it's own ELI5."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
68wp1s
|
Why isn't there an animal reserve for Amur tigers and leopards in Alaska or Canada?
|
Other
|
explainlikeimfive
|
[
"dh1vz3e"
] |
[
"Why would we destroy the environment the local species in order to preserve those animals? Probably it is a difficult idea to get support."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
aw3sl3
|
what gives us the feeling of butterflies in our stomach?
|
Biology
|
explainlikeimfive
|
[
"ehjqow9"
] |
[
"It's the sensation of blood being drawn away from 'non-essential ' organs in preparation for a fight or flight response. Your brain has convinced your body this is a life or death situation, so all the oxygenated blood is going to your arms and legs."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
cbsmc2
|
what lobotomies were meant to achieve and how/why it was believed they would fulfill their intended purpose?
|
I'm rewatching One Flew Over The Cuckoo's Nest, and it got me wondering why lobotomies were practiced? Why was is believed this procedure of drilling a hole into the brain would be beneficial to people and at the time, what supported this idea?
|
Biology
|
explainlikeimfive
|
[
"ethvwm5",
"ethw44v",
"etifc30",
"etj0p5p"
] |
[
"Mental illness was perceived as being in the frontal lobe of the brain, so if they kill the emotion area of the brain, or damage it, then they cure mental illness. It's just a shame that it turned most people in to emotionless vegetables. I guess that why electric shock therapy was used, to avoid making emotionless people in the hope that electric current would change the chemicals in the brain. As far as I know electric shock therapy is still used in some instances. I hope it's not, but. Yeah."
] |
[
4
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
ndetci
|
How exactly does electricity "know" to not flow backwards in a transmission line (or circuit)back to the source? Why does it move in one direction?
|
Physics
|
explainlikeimfive
|
[
"gya8yqq",
"gyaclmy",
"gyaj6l7",
"gyay65f"
] |
[
"Similar to air flowing through a hose on a machine, the end it's coming from has something pushing it along (a generator). This generator is making a voltage potential, and the place it's going to has a potential of 0 (it goes into the Earth after going through your stuff). Just like that high pressure air wants to go to where there's low pressure to even out."
] |
[
38
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
5xhr9x
|
How did they measure the speed of light?
|
Physics
|
explainlikeimfive
|
[
"dei9d5e",
"dei97o9"
] |
[
"People have wondered about the speed of light for a long, long time. As you can imagine however, the for the longest time there wasn't any real way to get a good measure of it just because it is too damn high compared to speeds we are used to here on earth. And so for the longest time it was thought to be infinite (when it was ever thought about at all). We could easily tell that sound and light traveled at different speeds, but it seemed like no matter how we checked, light was reaching human eyes instantly regardless of distance. One of the most famous (apocryphal) experiments done to test for it was done by good old Galileo Galilei. He said he set up lanterns on hills a mile away from each other and tried to see if he could detect a delay between when they were lit and when you could see them. Light is far too fast for human reaction times at that distance though, and so he wasn't able to prove anything either way. The first person to actually measure it was good old Ole Römer, a Danish astronomer in the 17th century. He was studying Jupiter's moons and noticed that his calculations on when and where to spot Io being eclipsed by the planet were routinely and periodically off by a few minutes. He was able to do the math to predict these delays, and was able to (correctly) deduce that the reason for the delays was that the sunlight that was reflecting off of Io wasn't instantaneous. It took time to leave the sun, reach the moon, and bounce back to Earth for observation. Using some geometry and best guesses at the time about the orbital distances of Earth and Jupiter, he ended up calculating that the speed of light was ~125,000 MPS. This figure is off by a bit (It's really ~186K miles per second, Römer's calculation on how long it took light to cross the diameter of the earth was off) but was actually remarkably close all things considered. In fact, when you correct for his single major error it's almost perfect! And this was in 1676! The next major change to our knowledge of the speed of light came from an English astronomer named James Bradley in 1728. The \"apple falling on Newton\" mythos around this one is that Bradley was sailing on the Thames one day when he observed how the pennant on the boat shifted positions as the boat moved about even though the wind was steadily coming from a single direction. How you move in relation to the wind changes what you see, and this can also be applied to light, not just wind. The earth orbits the sun in a circle, but light from stars is always coming from the same spot. As a result, the apparent position of the stars in the sky will move around as we orbit, with that movement correlating with the speed of the earth's orbiting compared to the speed of light. This amount is TINY of course, but it's absolutely measurable (and is about 20 arc seconds). This is known as the aberration of light. Bradley was able to calculate the speed of light with his measurements to around ~1% of the actual currently accepted value of C. There have actually been quite a few additional refinements since then, and perhaps a startling number of ways that people have designed experiments to test for the value of C. It's fascinating how resourceful people can be when it comes to discovering ways to measure something like that. Interestingly enough, in 1983 we ended up defining the SI unit \"Meter\" in relationship to C, specifically \"the distance light travels in a vacuum in 1/299792458 of a second.\" What makes this kind of neat is that it means C is now ALWAYS 299,792,458 meters per second, even if the accuracy of our measurements of it become more accurate over time. What changes is actually our understanding of the meter, meaning as we get more accurate instruments or experiments for measuring C, we actually change the subjective length of the universe instead of the speed of light!"
] |
[
56
] |
[
[],
[
"https://en.wikipedia.org/wiki/Fizeau%E2%80%93Foucault_apparatus"
]
] |
[
"url"
] |
[
"url"
] |
|
6q3245
|
Why do some people sneeze multiple times in a row while others only sneeze once?
|
Biology
|
explainlikeimfive
|
[
"dku5k3b"
] |
[
"If you sneeze multiple times, it's because your first sneeze(s) really just didn't do the job. The purpose of the sneeze is to get the allergen/irritant out of your nose, so if your first sneeze isn't forceful enough to expel it, you'll need another (and for some, another, and another, and another...) So really it just boils down to how powerful of a sneezer you are"
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
nm7p5x
|
What do comas feel like and how do they work?
|
Other
|
explainlikeimfive
|
[
"gzmzfcn"
] |
[
"I have a friend who spent some time in a coma (2 weeks, medically induced to help combat a massive lung infection caused by inhaling vomit as a result of drinking far, far too much. Almost killed him.), he said he was essentially dreaming the whole time, far as he was concerned he'd been skiing in the mountains and had bungee jumped from a helicopter whilst naked in bed amongst other things all punctuated with drinking and partying. He'd had a wild time! One odd thing was for a while after he woke up he kept pointing things out that weren't here, like his dreams were bleeding through to reality for him, he insisted there was a plane flying overhead (a jet fighter I think) at one point and got annoyed that nobody else could see it haha."
] |
[
10
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
5o8vh8
|
Why can't we make our fingers limp when we relax them?
|
Biology
|
explainlikeimfive
|
[
"dchkcc2",
"dchkc8i"
] |
[
"You can make them as limp as the joints and ligaments allow. Your fingers are actually connected to muscles in your forarm which control them by ligaments that run through your hands, and those have a certain basic tension."
] |
[
5
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
kphdmy
|
Trying to explain probability to friend
|
I was talking to my friend about how the odds of landing multiple coin flips works and we agreed, but he then went on to say that in roulette you should bet on numbers that it hasn't landed on in a while because it is more likely to land on those. I tried to explain that previous events don't influence future events in this scenario. When I asked what is the probability of flipping a heads after flipping 10 heads in a row he said it was not 50/50. I don't know how to explain that this is wrong. * he thinks this is just how probability works, he said if it didnt work like that you would get like 80 heads and 20 tails...
|
Mathematics
|
explainlikeimfive
|
[
"ghxcg5q",
"ghya1wl",
"ghxbvua",
"ghyeww9"
] |
[
"There's a difference between taking something as a series or a unique case. Coin flip is 50:50. Every time you flip the coin. No exception. *But* if you say what are the chances of flipping eleven heads in a row it's ridiculously small. So twelve times in a row even smaller. However, the twelfth flip is still 50:50. There is no \"due.\""
] |
[
11
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
ahk7zz
|
Why did early color TV programming look so artificial like the color was added in later?
|
URL_1 This is from the early 1960s and President Kennedy's skin color looked unnatural, as everyone else's. To me, the quality is like early 1900s colorized pictures from National Geographic that was added later by hand. Most of the JFK footage is black and white and there are some color films but they still look off URL_0
|
Technology
|
explainlikeimfive
|
[
"eefbxhk"
] |
[
"Film ages, and with age, fades. I see it when I look at old still pictures of family from those days."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
66olfd
|
How does animal/plant create some of the most potent poison out of nothing?
|
i mean it just soil and water for plant, normal food for animal. yet it can create poison that can kill whole village out of single drop.
|
Biology
|
explainlikeimfive
|
[
"dgk281a",
"dgk5z1g"
] |
[
"But it's not out of nothing! Have you ever played with Legos? Everybody starts with the same building blocks. Maybe you couldn't make something huge out of it -- but someone else certainly did. It's similar here. For plants, it's not *just* soil and water. There are nutrients in there; there are sugars and other things the plants can get from the soil. And the plants that are known to make toxins take these building blocks and rebuild them to become toxins. Think of yourself as a human. You just eat normal food; how do you get things working on a cellular level? How do your sodium-potassium pumps work; how do your cells split all the time? It's because we can break up the food we eat and get nutrients out of them - carbohydrates, proteins, fat, and so on. Humans may not have the right mechanics in our cells to produce toxins, but other plants and animals do."
] |
[
17
] |
[
[],
[
"https://en.wikipedia.org/wiki/Histamine"
]
] |
[
"url"
] |
[
"url"
] |
9qkzna
|
California’s Prop 8 which would regulate the amounts outpatient kidney dialysis clinics can charge for dialysis treatment
|
Other
|
explainlikeimfive
|
[
"e8a1alb"
] |
[
"What do you mean by \"studies\"? There's no study that can be done into whether or not clinics overcharge as that is not a scientific question. Nobody can study whether or not clinics reinvest enough into patient care as again, that's a philosophical question and not a scientific one. & #x200B; If you explain what kind of studies you are looking for, maybe we can help you search."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
6x9iga
|
What effects to game developers use to make massive, open world games (such as GTA V or Skyrim) seem so huge while still feeling so proportional?
|
For example; Trevor tells Michael in GTA V that he is a few hours up the road from LS. And while it looks and feels like a long distance, it only takes me a few minutes of real time.
|
Technology
|
explainlikeimfive
|
[
"dme8ft2"
] |
[
"For the case you mentioned, you're in the truck with Trevor's goofy sidekick, right? I can't remember his name, but I do remember the conversation he and Trevor have in the truck to be pretty boring. I'm sure that makes the journey feel longer. Also, the time-of-day effect in the game follows the (accelerated) game clock, so you see the sun setting as you travel towards Los Santos."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
6vdggj
|
How does the skin grow back with the same fingerprints?
|
Biology
|
explainlikeimfive
|
[
"dlzjwkm"
] |
[
"If you only damage the top layer of the skin, the epidermis, the underlying dermis contains the information to regrow the fingerprints in the same way. If you damage the dermis, you can cause scarring that prevents the fingerprint from growing back in the same way."
] |
[
15
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
b3zcte
|
With leaves converting sunlight to supply nutrition to the tree, how do deciduous trees after losing all their leaves survive and rejuvenate?
|
Biology
|
explainlikeimfive
|
[
"ej38q8i"
] |
[
"In the fall when you see leaves changing color, it is because the plant is working on sucking every bit of nutrients it can out of the cells of the leaf and then storing those nutrients in the roots for the winter. In the spring the longer days tell the plants that it is time to send those nutrients and a bit of extra sugar energy to the branches and buds to jump start leaf growth. As the leaf starts to grow the plant quits sending sugar to the leaf but continues to send water and minerals from the soil. The leaves change carbon dioxide and water into sugar and oxygen: 6x(CO2 + H2O) into 1x(C6 H12 O6) + 6x( O2) All summer the plant takes this sugar from the leaf to build new stems and roots. When the growing season is done for as long as it can it stores any that is left in the roots for next year. TLDR; the energy made by the leaves never stays in the leaves. The leaves are just there to feed the plant."
] |
[
10
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
9ezh0c
|
Why do Americans seem to trivialize racism, sexism, slavery (etc.) because it was "in the past", but make a big deal every year about remembering 9/11?
|
Culture
|
explainlikeimfive
|
[
"e5smgmn",
"e5smixb"
] |
[
"Things we've done bad = Trivial. Things others have done bad = The most important thing in the world."
] |
[
11
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
7iqtew
|
How does glass shatter when run under super hot water or in a dishwasher?
|
Chemistry
|
explainlikeimfive
|
[
"dr0phzr"
] |
[
"When things heat up, they expand. This is true for most types of glass†. When you heat something up unevenly, the heat can bend/warp it. Glass no likey bending. The resulting stress can cause the glass to break. † Yes, they make special borosilicate glass with very low coefficient of thermal expansion, but I presume the OP is talking about ordinary glass."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
6u25nu
|
What would happen if the US were to lose its power?
|
Other
|
explainlikeimfive
|
[
"dlpakr0",
"dlpa7x9"
] |
[
"Political/military power? China and Russia would probably accelerate their military buildup and start asserting more and more regional and global influence to help fill the void. China would probably become a lot more aggressive in the south china sea/sea of japan. It's unlikely any country would attempt to outright invade the US - too much to lose economically and militarily (so many guns with private citizens!) and not a ton to gain. Electrical power? Mass chaos initially, probably protests and riots if it weren't resolved quickly. Anything more specific would require more details about how we suddenly didn't have any electricity."
] |
[
4
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
73cwu2
|
If you can get the same degree from any college, why does it matter which college you go to?
|
I want to get a degree in Computer Science. The reputation and cost of the college I go to are near all the reasons I can think of.
|
Other
|
explainlikeimfive
|
[
"dnpe2m1",
"dnpdnt3",
"dnpdicn"
] |
[
"You're paying for 3 main things in my opinion. The quality of the educator. Your professors at a lower tier school may just know how to regurgitate the information they know back at you where a top tier school will have you being taught by professors and doctoral candidates who are currently contributing to the field. The quality of the labs/facilities. I can get a physics degree from Sacramento State and UC Berkeley but only one of those schools owns a functioning nuclear reactor. The relationships you will foster while attending the school. The more prestigious the school the more prestigious the people who you will be attending with. My degree from Sacramento State will get me work sure, but I did not meet anyone important with connections in government/industry. The people you will meet at a top tier school can get your foot in the door if your grades don't exactly set you apart."
] |
[
24
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
5uzk3j
|
Since many of the clinical "decisions" made by doctors in the healthcare system are dictated by consensus guidelines, why can't many of the doctors be replaced by computer algorithms?
|
There are clear rules and guidelines for many, if not most, situations encountered by doctors in the daily hospital routine (I'm a doctor myself). Why can't at least a part of the diagnostic and management processes be automated? Certain physical examination skills can be made by personnel that will be specialised only in that, and the rest of the patient reception and anamnesis can be made by a computer program that can elaborate all the data and come up with the next best step, be it a chest x-ray (that can also be interpreted by computer) or a certain dose of a certain medication.
|
Biology
|
explainlikeimfive
|
[
"ddy2n7z",
"ddyfl6h"
] |
[
"I remember reading an article that suggested that 80% of what doctors currently do will eventually be replaced by a computer. You're definitely right about increasing reductionism/specialization in medicine, and that's not going away. I think the main reason human doctors can't be entirely replaced is due to the importance of interpersonal relationships. When my folks got sick I didn't want to speak to a robot, I wanted to have a human being empathize with me. Sure, I was familiar with the medicine, and sure a computer could have told me the same prognosis, but seeing a look of concern in someone else's face and talking it over was a relief. The next reason depends on specialty. For instance, certain surgical techniques are obsolete due to advancements in technology. And like you said, many clinical scenarios can be simplified. However, the fundamental implementation still rely upon human doctors understanding the underlying concepts, especially in a situation where those technologies are unavailable. Lastly, nuances. There are so many nuances in patient behavior/history that can't be easily codified that have clinical significance. Many times life experience allows healthcare workers in general to make decisions based on social/behavioral cues that a computer would never realistically perceive."
] |
[
8
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
brr06q
|
How do bodily functions work when someone is in a coma?
|
Biology
|
explainlikeimfive
|
[
"eofw0zv",
"eofwib1",
"eofuxpy",
"eoghfb9"
] |
[
"It's auto pilot; it just happens. It's contained and managed most simply by briefs aka 'adult diapers' if you're not into promoting respect. Specifically for urine: Texas/condom cath to mke it easier for caregivers. Maybe an indwelling cath, but this shouldn't be used as a long term solution. A suprapubic cath is a longer term solution. For BMs/poop: One could get a colostomy bag to manage it easier... ish."
] |
[
15
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
5z5ajq
|
What is te difference between pansexual and bisexual
|
Repost
|
explainlikeimfive
|
[
"devcsn8",
"devctp8",
"devcroj"
] |
[
"\"Bisexual\" people are attracted to males and females. The root of the word is \"bi,\" which means \"two.\" \"Pansexual\" people are attracted to males, females, transgender people of all points in the spectrum of transition, and to people who don't closely fit typical gender roles. The root of the word is \"pan,\" which means \"all.\""
] |
[
7
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
f5xswz
|
can anyone explain why salt accelerates corrosion
|
Chemistry
|
explainlikeimfive
|
[
"fi1fspq"
] |
[
"As I recall, salt makes water conductive. The movement of electricity through water is part of the process of corrosion, as the reaction which forms rust is similar to the reaction in a battery. Water without salt is not very conductive, but water with a lot of salt is very conductive."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
67zdz0
|
Why are there four pulmonary veins leading back to the heart from the lungs, but only two pulmonary arteries leading out of the heart?
|
Biology
|
explainlikeimfive
|
[
"dguiheu"
] |
[
"Because the pulmonary veins are a lower pressure system, they need a larger collective diameter to allow for reasonable flow and filling of the left atrium within a reasonable time. There are only two pulmonary arteries because the right ventricle can push blood at a higher pressure and adequately perfuse the lung."
] |
[
23
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
fjke9c
|
Why is the media in America being hated on so much during these times?
|
Culture
|
explainlikeimfive
|
[
"fkne1z2",
"fknfhw4"
] |
[
"The American media business is in grave trouble. Instead of funding from a stable source, like the BBC has, US media firms are funded by advertising. In recent years, this system broke down, viewers no longer choose news content for its fact content, like in the boring days of Walter Cronkite. Instead people watch news for its opinion content, from The Daily Show to Fox & Friends. These shows seek to entertain their audience, and share a little news that reinforces their opinions. This is bad, very bad. Many sane people hold media in very low regard as a result. News should go back to news, though this is unlikely."
] |
[
16
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
7ch067
|
how does the body correctly sort food and fluid (especially when you eat and drink together)?
|
For example I have seen some eating contests where the participants eat huge quantities of food and drink water to held them “down” it quickly. When it gets down your food pipes* how does the stomach and bladder get their individual shares of what’s been consumed?? *forgot the sciency name.
|
Biology
|
explainlikeimfive
|
[
"dpprnim",
"dpprmcr"
] |
[
"> When it gets down your food pipes* how does the stomach and bladder get their individual shares of what’s been consumed?? The sorting happens in the intestines. It makes intuitive sense that the solids you eat become poop and the liquids you drink become pee, but that isn't actually true! Everything you swallow goes to your stomach, where it all gets mixed and broken down into a soup-like consistency. Then it goes to the intestines. Your intestines absorb the water out of it (including water that used to be in solid food), and absorb the nutrients. What's left over at the end of all this absorbing is poop. Poop also contains a lot of old, dead cells from the intestinal walls, and bacteria. All the water and nutrients that got absorbed will flow around in your bloodstream, going where they need to go. Once this is done, the extra water is filtered out by the kidneys, because a lot of the waste products we need to pee out (like urea) have to be dissolved in water."
] |
[
12
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
fw7f07
|
How do misters (such as hose) work?
|
Also the kind you see with a setting spray, hairspray, etc. How does the flow of liquid get so fine like that?
|
Engineering
|
explainlikeimfive
|
[
"fmmpqbp"
] |
[
"Air Flow All atomizers work on the principle of air flow and suction. When horizontal air passes over a vertical tube, it causes the air and liquid inside the vertical tube to be pulled upward. Classic atomizers use a squeeze bulb to store a lot of air that moves quickly over the feeder tube when squeezed. The bulb has two one-way valves located at either end. When the bulb is depressed, the valve leading into the tube that leads toward the bottle is forced open by air pressure while the valve leading to the outside is pulled closed. When the bulb is released, the rubber inside returns it to its original shape, closing the valve leading to the tube, and opening the valve to the outside so that air can fill the bulb. Reservoir and Feeder Tube The perfume rests in the body of the perfume bottle, or \"reservoir.\" The vertical feeder tube is partially submerged in the reservoir and connected to the bottle's lid, which also houses a tube that connects the squeeze bulb and the nozzle. The vacuum created by the passage of air pulls the liquid up into the feeder tube and pushes it out through the nozzle. When the airflow stops, a small amount of liquid remains in the tube and, because of the cohesion properties of liquids, will act as another mechanism to pull perfume up the tube once the bulb is squeezed again. Nozzle The nozzle is the end of the horizontal tube, and is usually made of metal or plastic. When the air and liquid perfume pass through the nozzle, it causes the perfume to break up into small drops and mixes it with the air. The restriction at the end of the nozzle, called a \"venturi,\" speeds up the air and liquid mixture causing the liquid to break up and the air to disperse it widely. Depending upon how hard the squeeze bulb was squeezed, the amount of liquid and its distance dispersed changes. Atomizing \"Atomizing\" does not mean to break down into its component atoms, but rather to break a large body up into small, discrete bodies, typically suspended in another medium. In this case, the liquid perfume is a mixture of oils, alcohols, water and dyes. When the air flow pulls some of the liquid out of the reservoir and mixes it with the air flow, the liquid breaks up into drops suspended in the air, each of which has the same ratio of oils, alcohols, water and dyes. URL_0"
] |
[
3
] |
[
[
"https://sciencing.com/perfume-atomizer-work-4568884.html"
]
] |
[
"url"
] |
[
"url"
] |
bfs16k
|
Intuitively, that why P(1-notA) is preferable/correct way to determine probability rather finding P(A) ?
|
(Someone explained it very intuitively (to the point it felt obvious just by reading) in here on reddit before, but I lost the account I had saved it in, and couldn't find out again.) & #x200B; EDIT : Maybe I should've asked why 'and how does it exactly work' ? My bad...
|
Mathematics
|
explainlikeimfive
|
[
"elg66s3"
] |
[
"It's true only in certain examples. And it's not more 'correct' than the direct way, just preferable because it's easier, or the direct way is not feasible. One example: you roll a die 20 times. What's the probability that 6 appeared at least once? Direct way would be calculating the probability that 6 appeared on first roll only, plus the probability that it appeared on the first and second rolls, first second third, and so on, plus only second, plus only second and third... You can see where it gets crazy. Rather, if you think of it as \"hey the probability of rolling a 6 in at least one roll is just 1 minus the probability of NOT getting a 6 in any roll\", you'll quickly get the answer: 1 - (5/6)^20. Simple. You'll get the same answer either way."
] |
[
8
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
hvvs92
|
Why do people always (or usually) boil crabs and other seafood alive?
|
Biology
|
explainlikeimfive
|
[
"fyvuypp",
"fyvu55w"
] |
[
"Crabs can be killed before boiling by clipping their front head region by the eyes (this kills the crab meme). This does make the crab less appealing when cooked. When you have a bag of clams or mussels, it would be very time consuming to open up each shell to kill it. Furthermore, boiling living shellfish relaxes the muscles holding the shell closed. This means that living shellfish will have open shells after boiling while dead ones will remain closed (open shells before cooking should be picked out prior to boiling). This is important to identify to reduce risk of food poisoning. Other types of seafood like fish are killed since they need to be prepped (descaling and gut removal). Having a living fish flap around would be dangerous since they do have sharp fins and barbs."
] |
[
12
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
eb0c3l
|
Why does putting clear (scotch/packing) tape on a frosted window let you see through it?
|
Other
|
explainlikeimfive
|
[
"fb0eoas",
"fb2057h",
"fb3ch83"
] |
[
"Frosted glass is simply glass with a (chemically) roughened surface which causes the light passing through the pane to diffuse in all directions, instead of letting straight through. (Scotch) tape is essentially a clear plastic surface coated with a thin layer of transparent adhesive. When you stick it to frosted glass the adhesive fills the small cavities on the glass surface which were made by the chemicals used to frost it. The adhesive thus smoothens the surface, counteracting any diffusion. This also means that the tape trick only works on chemically frosted glass, or mechanically frosted glass with a fine texture, because the thin layer of adhesive can only smoothen out relatively small cavities in the glass. Edit: thanks for the silver! Edit 2: and thanks for the double silver and the gold!!"
] |
[
8379
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
cufjeh
|
How do bars and cafés keep flies away ?
|
I'm currently enjoying a beer in a downtown bar, and it made me thinking. At home, as soon as I leave a piece of bread or beer on the table, 5 minutes later about 10 flies are spawned. Yet in a bar, there are beers lying around all the time, and I'm not seeing a single fly, nor any fly traps. What gives ?
|
Other
|
explainlikeimfive
|
[
"extym1j",
"extxac8",
"exu2jjv",
"exu5bh3"
] |
[
"Well - many of them don't. For those that do - ridding yourself of insects basically boils down to two approaches. 1 - Repel them Insects are repelled by things like citronella and DEET - basically the more you can get into the air the better 2 - Attract and kill them Make an artificial carbon signature (by burning some kind of fuel) and getting them close enough to kill them or trap them Also maybe the bar is just cleaner than your house and/or has less still water nearby"
] |
[
19
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
e8tknh
|
Do submarines have anchors?
|
Engineering
|
explainlikeimfive
|
[
"faed96b"
] |
[
"Yes, they do. But they rarely use them. Source: 4.5 years on board a submarine. NEVER used the anchor."
] |
[
36
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
mon365
|
. Why do immunizations get injected into muscle. Wouldn’t it spread faster in your body if injected into a vein?
|
Biology
|
explainlikeimfive
|
[
"gu4p6cv",
"gu4pkgg",
"gu4p7ac"
] |
[
"Vaccines aren't meant to spread fast. They are meant to create a local \"infection\" in order to stimulate an immune response."
] |
[
30
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
c30gex
|
How come certain plant species and animals, etc can reproduce asexually with no issues developing in the offspring, but when creatures like us reproduce sexually, inbreeding with someone close to us results in lots of health issues and deformity?
|
Biology
|
explainlikeimfive
|
[
"ernspsa",
"ernu9uh",
"ernsv7y",
"erobuv0"
] |
[
"First, the dangers of inbreeding is greatly overstated. For most of human history we lived in small tribes and villages and... you know. You have to inbreed consistently for many generations to see a real problem. Species that clone themselves *do* have this problem, and it's precisely why reproductive solutions that recombine DNA evolved in the first place. When the entire population is clones, you risk excessive propagation of genetic defects and have a severe risk of infectious attack decimating the species. But, it's also super easy so some species opt to live with the risk and just brute force their way through with a gazillion clones."
] |
[
27
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
jkotr3
|
How does a dirt road develop and accumulate washboards?
|
Everything I've ever learned leads me to believe a dirt/gravel road should develop linear ruts instead of washboards. How is it that after a road has been graded, it inevitably develops a rhythm section similar to an old washboard?
|
Other
|
explainlikeimfive
|
[
"gakd84i",
"gakdycp"
] |
[
"It's caused by a self-reinforcing interaction between the car and the road that tends to make small defects bigger. No road is \\*perfectly\\* flat. If it were, washboarding wouldn't happen. So every road has at least small defects. When the tire goes over that defect it initially extends the suspension (assuming a dip) and the car starts to respond, but before it can get very far the tire slams into the opposite side of the defect. This compresses the dirt a bit, making the defect slightly deeper, and the car rebounds up. When it comes back down, it squishes the dirt again (though not as much), on and on until the suspension quits oscillating. Now the next car comes, and exactly the same thing happens, except each one is a little bigger so the \"wham\" is a little bigger and all the defects get a little larger. Each successive vehicle causes the defects to grow. Let that happen for long enough and you get a washboard."
] |
[
69
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
cwukvr
|
Why does minus minus = plus? e.g 14 - (- 5)= 19
|
Mathematics
|
explainlikeimfive
|
[
"eyf8f92",
"eyf9d78",
"eyf9i4a",
"eyf9iln"
] |
[
"To subtract a negative amount means to add a positive amount. Think about the number line. If you try to go down by a negative amount, you are going up. If you go down by zero, nothing happens. If you go down by 5, you go down. But if you go down by -5, you're moving up 5."
] |
[
6
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
b5667q
|
How does vegetable oil remove stickers and and sticky residues?
|
I was wondering how that "life hack" really works. It can't be dissolving the residue because oil is a nonpolar molecule right?
|
Chemistry
|
explainlikeimfive
|
[
"ejbh7t0"
] |
[
"I’d the adhesive contains a polymer, vegetable oil swells the polymer and breaks it down so it no longer has any adhesive or elastomeric properties"
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
expi9r
|
Why can we control certain parts of our body but not others? For example you can control the lungs and how they breathe but not the intestines on how they digest
|
Biology
|
explainlikeimfive
|
[
"fgavfyy",
"fgb8x9q",
"fgaxmer"
] |
[
"Because not only is there no benefit to having conscious control over something like your digestive process, but there's a serious drawback. There's only so much we can be consciously aware of at the same time. If our conscious minds were constantly were occupied with controlling our digestion or keeping our heats beating, we'd have no capacity left to do anything else."
] |
[
7
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
bh7aod
|
Why can't we understand animals?
|
For example dolphins communicate with whistles and clicks, why haven't we been able to interpret them or figure out what they're saying?
|
Biology
|
explainlikeimfive
|
[
"elqvzib",
"elqzwrq",
"elqiswq",
"elqj61l"
] |
[
"Well we can. If you look for information you will see that we know a lot about dog's communication. There is two problems that we face. & #x200B; 1) Animals communicate, but don't have a language. A language is precise, but communication is messy. Try communicate with someone without using language, you have far less diversity in the mean you have and that make your communication more limited and less complex than if you would use a language. & #x200B; 2) We need to observe the communications to understand it. It's easy to do with a dog, far less to do with dolphin, so of course we understand a lot less about Dolphin communication vs Dog communication."
] |
[
30
] |
[
[],
[
"https://en.wikipedia.org/wiki/What_Is_it_Like_to_Be_a_Bat%3F"
],
[],
[]
] |
[
"url"
] |
[
"url"
] |
efb3yy
|
Why do baloons do a huge bang when popped
|
Physics
|
explainlikeimfive
|
[
"fbzds4t"
] |
[
"The air in a balloon is at a higher pressure than its surroundings because the elastic tension of the balloon skin is pulling inwards. ... The high-pressure air that was inside the balloon is now free to expand and this creates a pressure wave that our ears hear as a bang. A simple google search told me that. . ."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
c14lxw
|
How is it that your nose can produce an almost endless amount of snot when you are sick, even after you blow your nose dry?
|
Biology
|
explainlikeimfive
|
[
"eraq9vl",
"eratpxv",
"erb71u4",
"erb6na6",
"erbcogc",
"erb5wk5",
"erbde45",
"erb9q1s",
"erb1m29",
"erba12x",
"erbb0yx",
"erbn0oq",
"erbbcr8",
"erbjoen",
"erbdrsj",
"erbmojy",
"erbbm97",
"erbdvcw",
"erbge5a",
"erbnts9",
"erblyeo",
"erc1w70",
"erbiknv",
"erbpxqc"
] |
[
"We've got pretty big sinus cavities inside our cheeks and foreheads. It can seem like your blowing your nose *forever* when you're sick, but we underestimate the amount of snot our noggins can store. Plus, if you're fighting an infection, your body's gonna keep producing more mucous to try and flush it out."
] |
[
5024
] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[
"https://www.vox.com/2015/2/11/8013065/mucus-snot-boogers"
],
[
"http://imgur.com/a/RSHfS",
"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3080316/",
"https://jet.com/product/detail/8cdd98658bfa4da381bca255361ea7be?jcmp=pla:ggl:All%20Products%20Catch%20All:All%20Products:na:PLA_344686020_23650353180_pla-61865531738:na:na:na:2&code=PLA15&gclid=Cj0KEQiAnb3DBRCX2ZnSnMyO9dIBEiQAOcXYH3HElT2zDzen-ip8bTQvnZHzJStXUOgvDO7njdtLfOwaAv9o8P8HAQ",
"https://www.ncbi.nlm.nih.gov/pubmed/12563939",
"https://www.reddit.com/r/explainlikeimfive/comments/5m9asi/eli5_how_come_when_youre_sick_you_can_blow_your/dc2d15w"
]
] |
[
"url"
] |
[
"url"
] |
|
988qkp
|
How does tickling work?
|
Dumb question but still curious
|
Biology
|
explainlikeimfive
|
[
"e4e6zen"
] |
[
"Very simply put; Tickling involves the same nerves that register pain, but the brain registers it differently - the body thinks it's under attack, but the brain says \"No, not exactly\", so the body gets confused and doesn't really know how to deal."
] |
[
20
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
kclxmw
|
Why does it take such a short amount of time to get drunk, but edibles (cannabis) can take upwards of hours to take effect?
|
Biology
|
explainlikeimfive
|
[
"gfrepha",
"gfreqi9",
"gfrt0ge"
] |
[
"It comes down to how your body absorbs the different chemicals. THC can be absorbed very quickly through the mouth in the form of tinctures and some candies. That is because the THC is quickly absorbed into the bloodstream through your mouth's mucus membrane. However, if you eat a brownie, the THC is absorbed through your gastrointestinal tract. Basically, you have to digest the cookie and the liver will process the THC. Hence why a cookie takes so much longer to take effect. Now alcohol is absorbed through your intestinal tract, specifically the small intestine absorbs ~80% of the alcohol, this can still take a little time but is still quicker. Additionally the other 20% is absorbed very quickly through the stomach, and even starts being absorbed in the mouth. I am not a doctor, but I did have to get my \"liquor license\" for my job, and also listened to a podcast about cannabis. I believe it was a StuffYouShouldKnow episode. Hope this helps."
] |
[
20
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
hqd8pp
|
What do you actually hear when you put your put your ear up to a seashell to "listen to the ocean"?
|
Biology
|
explainlikeimfive
|
[
"fxxjn1z",
"fxxhiou"
] |
[
"It's just the background noises amplified by the shell, you can get the same effect to a lesser extent if you cup your ears forward with your hands."
] |
[
10
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
kct0gs
|
is it more secure to use a passphrase over a password
|
I use a lot of passphrases for my passwords, their easier to remember and apparently as secure as a password, but I was wondering if the XKCD comic is still right, considering recent advances in processing power. I’ve seen lots of questions asked like this but they are all confusing.
|
Technology
|
explainlikeimfive
|
[
"gfsin2s"
] |
[
"It essentially boils down to the longer your password is, the safer. Brute force methods attempt to guess your password by trying each possible character at each position. For example, if your password is 3 characters long and only contains letters, a brute force algorithm would only need to guess 26 × 26 × 26 combinations. Each additional letter makes 26 times more combinations to try. Actual passwords of course can contain numbers and symbols which makes this number larger (and your password safer)."
] |
[
7
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
hipxsz
|
Do perfect mirrors exist? Could you trap photons in a perfect mirror container?
|
Physics
|
explainlikeimfive
|
[
"fwi7oqx"
] |
[
"Light *refraction* turns out to be the key to total light reflection on a surface. It's not really a mirror by definition, since the [total internal reflection]( URL_0 ) depends on the light's angle of incidence. It's the basis of fiber optic cables that can transmit pulses of light through snaking twists of a thin cable, across the Atlantic Ocean floor, for high speed data transfer. Transmission isn't optically 100%, but good enough for thousands of miles. To go beyond ELI5, there's also the issue of the lack of \"sameness\" of photons after interacting with matter. But that's too far afield. So the tl;dr answer is: no perfect trap for photon energy, but close enough for our needs."
] |
[
3
] |
[
[
"https://en.wikipedia.org/wiki/Total_internal_reflection#Critical_angle"
]
] |
[
"url"
] |
[
"url"
] |
|
6kxm2v
|
What's actually happening after lifting weights that makes the muscles feel like they're trying to push their way out of the skin?
|
Biology
|
explainlikeimfive
|
[
"djpkrbo",
"djppcpt"
] |
[
"You achieved the pump! They're swollen with so much blood that they are stretching the skin that's covering them taught. So it feels like exactly what it is."
] |
[
6
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
6pmkbs
|
What is Austerity?
|
Please can someone explain in simple terms what austerity is and why I hear about it so often on the news. Attached is The Economist definition...[The Economist — Austerity]( URL_0 )
|
Economics
|
explainlikeimfive
|
[
"dkqhrqm"
] |
[
"Governments spend money to help their citizens. This can take the form of government jobs, worker's pensions, welfare, health care or any number of other things. Ideally a government would be taking in approximately as much money in revenue as it spends. When a government spends more than it takes in then you have deficit spending. When deficits get too large they can negatively impact the entire country. Austerity is the practice of cutting back on government spending in order to bring it more in line with its revenue. This can be very painful in the short term for the people who are no longer receiving the benefits. If austerity is done poorly or too much then it can have a worse impact than the deficit spending did."
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
j3bngx
|
when ordering through a food delivery service with a discount, who takes the loss? The restaurant or the delivery service?
|
Economics
|
explainlikeimfive
|
[
"g7avx4m"
] |
[
"Either or. It depends on who is offering the discount. If McDonald's is offering a free order of Mcnuggets if you spend more than 20 bucks, then that's McDonald's cost to eat. If Uber Eats has a 30% off all orders if you spend more than $50, then no matter who you order from, uber will pay for that discount."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
ic8b7i
|
why does 0!=1?
|
I don’t understand why 0!=1. I know it has something to do with a mathematical expression: something called the “factorial” of a number. But please ELI5.
|
Mathematics
|
explainlikeimfive
|
[
"g21f3vc",
"g20wnmr",
"g20x7j7",
"g20z13k"
] |
[
"When you add numbers the \"do nothing\" number is 0. If you add 0 to anything you get the same number you started with. What would you expect the answer to be if you added no numbers together? You would expect it to be 0, and you would be right. With multiplication the \"do nothing\" number is not 0, it is 1. You multiply something by 1 and it doesn't change. By the same logic, you should expect the result of multiplying no numbers together to be 1."
] |
[
15
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
el5hqp
|
how does hand sanitiser work?
|
Biology
|
explainlikeimfive
|
[
"fdfqkf3"
] |
[
"The active ingredient is usually isopropyl alchohol. It kills bacteria by penetrating the cell membrane, after which it then coagulates proteins inside the cell. Most of the cell is made of various proteins floating in cytoplasm. So, basically it turns the cell into a solid and disrupts life processes. Edit: i just remembered a safety demo we do sometimes. Crack an egg in a glass, then stir in a little alchohol. It'll coagulate the egg white, just like the cell, turning it opaque. Also, just like your corneas. Wear your safety goggles!"
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
naodnn
|
Why do glass bottles have to be “recycled”?
|
Why can’t companies just sanitize and refill them?
|
Other
|
explainlikeimfive
|
[
"gxulvv4",
"gxux4mk",
"gxviued",
"gxuqd5d",
"gxvfn2z",
"gxvdrbk",
"gxvg5aj"
] |
[
"Some do - beer bottles for instance are reused that way. But there are a lot of those. For the most part, there are small numbers of a lot of different bottles scattered across the country, and collecting, sorting, and then returning those to the specific places that use them is not economically viable. Easier and cheaper to melt them down and make new stuff."
] |
[
87
] |
[
[],
[],
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
5lofv3
|
What determines your blood type and what's the difference between positive and negative?
|
In the womb, what determines blood type? I am AB positive, what's that mean and how does it compare to negative?
|
Biology
|
explainlikeimfive
|
[
"dbx8j5f",
"dbx8fi2"
] |
[
"What determines it: Genes. Your blood type is dependent on both parents, although the details get a little weird. Basically, blood types represent little bits of stuff sticking off of your red blood cells, which your immune system can interpret. Think of it like a bunch of ID badges or uniforms. If your immune cells recognize your stuff as friendly, it's all good; if not, your immune system attacks and destroys the cell. The important point is that your immune system is ready to attack whatever you DON'T have on your own cells. There are actually dozens of different things sticking off red blood cells, but the only ones we really care about are the AB system and the Rh system (the positive or negative part.) If you have the A thing only, you're type A. If you have the B thing only, you're type B. If you have both, you're AB; neither, you're O. The Rh system is another thing, and you either have it (positive) or you don't (negative.) Combine this all together, and you can be A+, B-, AB-, O+, whatever. Whatever you DON'T have on your cells, you make antibodies against, because it's foreign and weird. So, if you're A+, you make anti-B antibodies. If you're B-, you make anti-A and anti-Rh antibodies. If you're O-, you make antibodies against everything. If you're AB+, you don't make any antibodies. This gets important for blood transfusions, since you can only get blood you won't destroy. O- blood can be given to anyone since it has nothing offensive on it, while people with AB+ blood can receive any type."
] |
[
10
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
lbtisi
|
What is a "social market economy" ?
|
And what are some (good) examples of one?
|
Economics
|
explainlikeimfive
|
[
"glw2gev"
] |
[
"A social market economy is a capitalist economy with a strong welfare and regulatory state. It is the same as a social democracy. The Nordic countries think they are doing this."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
goekrg
|
I kind of get how the old computer mouse with the ball would work. How do the newer ones with a red light work?
|
Technology
|
explainlikeimfive
|
[
"frfe04n",
"frfe6wt",
"frfdx7f"
] |
[
"Optical mice have an LED (the red light) that shines downward onto the surface before it reflects back and is picked up by a sensor. A lens collects the reflected light and forms an image. It would appear as a small black and white section of the mousepad or surface the mouse is on. While this is going on, a camera is taking rapid pictures of the image (~1600 per second). The pics happen so fast that they overlap. An optical navigation engine in the mouse compares those pictures and looks for commonalities between captured frames to determine how far apart they are. That information is then converted into X and Y coordinates to indicate the movement of the mouse."
] |
[
15
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
gte57m
|
How do Captchas work and how effective are they in weeding out bots?
|
Technology
|
explainlikeimfive
|
[
"fsb18tj"
] |
[
"Captchas original were just squiggly text. You may still see these. Computers aren't good at machine vision so they cannot read them but humans can. reCaptcha was the next generation of that, and they gave you two words to type. One was a control (they knew what it was) and they other, they actually didn't. They came from the Google project to scan and digitize books. The books were old and the computer couldn't read all the words so they used humans to transcribe for them. If 10 people agreed what the word is, and entered it correctly, then it was accepted as correct; in essence you're helping them digitize books The iteration where you have to tag images (click all images with a sign) is again an issue of machine vision and you're helping training AI and reverse image search The one where you click a box to merely say you're not a robot... though there are videos that show robots doing this, they're actually watching how the mouse moves along the screen, or measuring how the box is checked on mobile devices....such that they know a human did it, was not automated. I don't have figures for how effective they are at stopping bots, but they work. As tech evolves, they try to make the process easier, but also leverage it to help train AI to solve new problems. Luis von Ahn is the inventor of them (it was his PHd thesis and he's also the guy who invented DuoLingo...and the reverse image search). There are tons of podcasts and videos about him talking about the CAPTCHA and how it evolved and what the new goals are. Originally they were designed to just stop bots. But he realized how much time is being wasted every day on them so he retooled them to solve computer science problems. So now, while they stop spammers, they're really experiments in improving security and AI issues and each time you do one, you're helping train a system."
] |
[
13
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
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