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|---|---|---|---|---|---|---|---|---|---|---|
dhmha6
|
Why exactly do buildings, mountains etc seem greyed out the further away they are?
|
I am not sure if my Q makes sense, but I am in a car, headed towards a city and the skyscrapers seem almost "faded". The same thing happens with distant mountains. Howcome?
|
Physics
|
explainlikeimfive
|
[
"f3oycpt",
"f3oynh9"
] |
[
"There is stuff in the air blocking (scattering) the light and making it less colorful and dimmer. After a rain storm you will often notice they look brighter because the air has been cleaned by the falling water."
] |
[
19
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
7lnxdz
|
Why does human and livestock feces contaminate/pollute rivers when fish and native species also poop near or into the water?
|
I was watching a documentary about India's rivers and they mentioned how livestock and human waste (along with lots of other shit) was being dumped into the water and this was making it dirty and unsafe to drink. I've been confused by this before because I always assumed that fish and other animals just shit into or near the water. So my question is, why does human and livestock poop make the water unsafe when fish and other animals have been pooping into the water and they've been drinking that with no problem for thousands of years?
|
Biology
|
explainlikeimfive
|
[
"dro2qpl",
"drnosrg",
"drny21i"
] |
[
"Ecosystems are about balance. A river is going to have a certain capacity to break down wastes, fish or human, and once you exceed it, it will because unbalanced and most of its creatures will die off. For centuries, there was balance. Humans could only produce so much food, and populations were more stable. From 1500 to 1700, India's population was around 100 million, and grew slowly, so the rivers were, for the most part, able to keep up. With advances in agriculture, medicine, and ironically, sanitation, India's population has increased by 13x in only 300 years. That's 13x as much waste, completely overloading the ecosystem's capacity to break it down."
] |
[
8
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
adro6c
|
can you feel whether you are upside down or not In space?
|
Biology
|
explainlikeimfive
|
[
"edjog66",
"edjov3s"
] |
[
"There's no such thing as \"upside down\" in space, or more specifically in microgravity. Upside down is relative to gravity - if you head is pointing to the direction of gravity, you are upside down."
] |
[
25
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
dsnzdh
|
- what is the body doing during the "ahhh" phase of "ahh-choo"?
|
Biology
|
explainlikeimfive
|
[
"f6qn9h4",
"f6qnb8p",
"f6qtip4"
] |
[
"Inhaling. you can't sneeze if you don't have any air in your lungs. When you go \"ahhh\" you're breathing in as much air as you can so when you go \"choo\" you have some air pressure to clear out the slime, mucus and irritants your body doesn't like."
] |
[
44
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
6zmqvn
|
Why is bird feces white but all other animals are brown?
|
I know I could look it up but Google won't explain it like I'm 5 so
|
Biology
|
explainlikeimfive
|
[
"dmwe9kj",
"dmx21sg",
"dmwmnaj",
"dmwmupp",
"dmwdysb",
"dmwvhle",
"dmwqk2g",
"dmwq6f7"
] |
[
"Bird's excrement is actually a combination of their \"urine\" and feces. Birds don't \"pee\" like mammals, they excrete all waste from the same orifice called a \"cloaca,\" which is like a fancy butthole. The white junk is nitrogen and urea and other stuff that would normally be excreted in urine in other animals."
] |
[
2576
] |
[
[],
[],
[],
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
67up0h
|
what does long term laxative abuse (as a 'weight loss' regime) do to the body?
|
A friend mentioned she's been doing this. I can't seem to convince her to stop.
|
Biology
|
explainlikeimfive
|
[
"dgthaft",
"dgtdzcz",
"dgti0l0",
"dgtgvvr",
"dgu23hq",
"dgtgyzk",
"dgths2n",
"dguhg68"
] |
[
"She loses electrolytes every time she uses laxatives to purge - prolonged imbalance in electrolytes can lead to heart problems, brain swelling, seizures, coma and death, among other things. She may also suffer from edema, where her body holds onto water and swells. Repeated diarrhea may lead to a tear in her bowels and bleeding. There's also something called \"reflex constipation\" where the bowel stops being able to move things along as it should. She might also permanently break her digestive system, so she might end up needing a colostomy bag. Colon cancer risk increases. Edit: two words"
] |
[
147
] |
[
[],
[],
[],
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
bhs0kl
|
Why adults don't fall from bed while sleeping?
|
Biology
|
explainlikeimfive
|
[
"elvep4c"
] |
[
"Very good question! I'll answer your question by doing another question and explaining some things that'll help you understand. Here we go. Statistically speaking, the adult human shouldn't fall from bed but somehow there's a small percentage that does. Why? Sleep paralysis, sleepwalking and falling from bed have something in common. The Brainstem! That's a part of the brain that regulates our most basic functions like breathing or our heart rate. Also something important is that it is in the base of the brain and connects it with our Spinal Cord. But what does the brainstem do in our sleep? Well it's quite simple! Since that's our connection between our brain, which is where the \"orders\" come from, and body; when we are sleeping the brainstem blocks EVERYTHING! Except for our heart rate and breathing which it already controls, hence us not dying! But why does it do that? Because when we are sleeping, there is one phase (out of 4) in which our brain is actually not resting, but is working like crazy! In this phase, which is the one where dreams happen, our brain is working on all those problems we had during our day, throwing ideas in the air and making crazy scenarios. Imagine if all that information wasn't contained! We would act everything that is happening in our dreams in real life. But wait. Those are sleepwalkers, aren't they? Indeed! Sleepwalking, falling from bed and sleep paralysis are caused by \"errors\" in our brainstem. While sleep walking and falling from bed is caused by the brainstem not blocking everything properly, sleep paralysis is the exact opposite, it happens because the brainstem didn't unblock everything in time and we woke up, making us unable to move. And what about children? Why do they have more propensity to sleepwalking, talking while asleep, falling from bed, etc? Because of our brain age. When we are born our brain has an incredible amount of cells, called neurons. And as time passes, our brain goes \"well, having this many neurons is USELESS. We should only be using what we need, not everything we have\" and as age goes by, the number of neurons starts decaying. But what does that have to do with sleepwalking, talking and falling in our sleep? Well, from the time we are babies to our adulthood, many neurons are not gone right away. That means, there are many many pathways through neurons that will be gone when we reach adulthood, but when we are young our brainstem doesn't control and therefore cannot block. Have a nice day < 3 if you have questions I'm here for you PS: I LOVE THESE TYPE OF QUESTIONS"
] |
[
10
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
akttnr
|
How can there be surgeries lasting more than a few hours? Are they truly that intricate, or do things go wrong?
|
Biology
|
explainlikeimfive
|
[
"ef7v65o",
"ef7xctm"
] |
[
"They are truly that intricate. When my late mom had breast cancer she underwent a procedure that was extremely new at the time, but is commonplace now. It was called a tram flap reconstruction surgery. Basically the surgeon did a modified mastectomy, meaning he took the entire breast, but left some of the unaffected lymph nodes in her chest. At the same time a reconstructive surgeon made a cut along her bikini line, basically from hip to hip. He then sectioned a piece of her abdominal muscle without totally removing it, and then moved it and the attached fat under the skin, still attached and getting blood flow, to rebuild her breast. It was a new surgery for both surgeons at the time, although they had been extremely well trained in what to expect, and it went perfectly. The surgery that day took eleven and a half hours, although now that same surgery is regularly completed in eight hours or less. Surgery is incredibly complex, and everything must be done perfectly the first time around. It takes time."
] |
[
16
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
b90xr9
|
What is the purpose of the human hymen?
|
It can’t just be a guarantor of virginity. Hymens can tear for all sorts of reasons, not just from first time sexual intercourse. So what is it actually there for?
|
Biology
|
explainlikeimfive
|
[
"ek1drab"
] |
[
"I do know for sure that the hymen is not an indicator of virginity in any way. It can be broken in many ways including masturbation, using tampons, horseback riding, and many others, it can even grow back in certain cases. However, from what I can tell, no one is really sure what anatomical purpose it has."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
94wh4c
|
Why is it so easy to cross our eyes towards our nose but seemingly impossible to push them away from our nose?
|
Biology
|
explainlikeimfive
|
[
"e3o9orz"
] |
[
"Because going towards the nose you're focusing on one point. Going away you're trying to focus on two completely different ones."
] |
[
10
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
5xfqf3
|
how is that we hear that the world is over populated yet we have countries like Spain saying they need families to have more babies?
|
Economics
|
explainlikeimfive
|
[
"dehsdrm",
"dehtjta",
"dehr272",
"dei7rtq"
] |
[
"Why are we concerned about losing forests when there are plenty of trees by my house? Why are we concerned about global warming when it's cold outside right now? My house isn't representative of world's forests, my city isn't representative of the world's climate, and Spain isn't representative of the world's population problem."
] |
[
17
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
cjdyua
|
the definition of “holistic”
|
I looked up it up and i still don’t understand
|
Physics
|
explainlikeimfive
|
[
"evcr3nk",
"evd3ip9"
] |
[
"Holistic is used contextually where there has been a tendency (largely in modern scientific approaches) to break things down to isolated components. Taking a \"holistic\" view reminds us that things in isolation result in a simplified and sometimes artificial perspective and that \"backing up\" and looking at a whole system can be a better way. For example, one might contrast mental health of yesterday with mental health of today by saying our view today is much more \"Holistic\" in that we understand that our biological functions have a tremendous impact on and are impacted by our mind. We spent a lot of time trying to separate the mind a single system from the rest of the body, but in doing so made great advances, but also often missed the forest through the trees."
] |
[
5
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
a8df2c
|
If you're going down the road at 60~70 mph and roll down a window, why does it make that whomping sound that hurts your ears?
|
Physics
|
explainlikeimfive
|
[
"ec9qtaw",
"ec9sq5h"
] |
[
"because if you have only one window open, the air has no way to escape the car as new air enters. the sound you hear is large bursts of air entering the car while the same large amount of air is trying to exit the same area."
] |
[
8
] |
[
[],
[
"https://en.wikipedia.org/wiki/Helmholtz_resonance"
]
] |
[
"url"
] |
[
"url"
] |
|
9qyrrn
|
How do stock prices CHANGE with purchase and selling?
|
Economics
|
explainlikeimfive
|
[
"e8cpwmf",
"e8cq02o"
] |
[
"In order for someone to buy stock, that means that someone else is selling it. A LOT of someones. That's what the 'Ask' is when you're looking at stock prices: what the lowest asking price is for a seller of a given stock. If all of the stock being offered at a lower price is bought up, then it'll leave only sellers who were looking to get a higher price for the stock they're holding. So, now you have a higher lowest 'Ask', since all of the cheapest stock was bought up. People will see this, and likely decide that the stock they're holding is potentially more valuable, since there is apparently a very interested buyer; so they're likely to place an even higher price on the shares they're holding. This drives up the price of the stock even more. Reverse everything for a stock price going down, as buyers are 'Bid'ing less and less for shares, because they're just not interested in paying what sellers are asking for, and holders finally cave in to the lower offers to offload a stock they don't have faith will hold its value."
] |
[
8
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
mq8efi
|
What are these circles with a dot in them that I see sometimes floating before my eyes?
|
Very often, especially on rainy days, I see those circles before my eyes, and I always assumed them to be dust particles on my eye or very round floaters, since I saw that on Wikipedia. I however just stumbled across exactly those circles with the dot in a YouTube video which made me doubt the dust particle theory. Since this description is very vague, [here]( URL_0 ) is a screenshot of what I meant. & #x200B; Thanks in advance
|
Biology
|
explainlikeimfive
|
[
"gufpx80"
] |
[
"Supposedly floaters are bits of your vitreous humor (the gel inside your eyeballs) coagulating/jellyifying and breaking off. When they pass through the eye, they block light and cast shadows, appearing as floating objects. Another explanation I've heard, but can't find any science to support, is that floaters are made of bits of torn cornea (the outer surface) floating by in the liquid of the eye. I don't put much stock in this as I can watch the same one for a while--and they always move when you try to look at them."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
9p5yyj
|
Why do countries have different names in different languages? Shouldn't names be universal like they are with people?
|
Culture
|
explainlikeimfive
|
[
"e7zccxa",
"e7zeshm",
"e7zk5o8",
"e7zc4nc"
] |
[
"Names aren't universal with people at all. Different languages pronounce names differently, or have different \"versions\" of common names."
] |
[
19
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
gz6u3e
|
What happens to my house if I stop paying property taxes?
|
Economics
|
explainlikeimfive
|
[
"ftej8f0",
"ftej4pu"
] |
[
"Usually a tax lien or tax foreclosure, basically your house will be taken from you eventually"
] |
[
3
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
6zq2dc
|
is it true that if you take a loan at a bank, the money is created through your loan contract by extending the banks Bilance sheet on both sides?
|
Economics
|
explainlikeimfive
|
[
"dmxctnt"
] |
[
"Sort of. It would be more accurate to say banks allow money to travel through time. You have $1000. You don't need to spend it, and you don't plan to anytime soon, that is just money you are setting aside in case of emergency. You have it, but you are not using it right now, so you let a bank hold on to it. Somewhere there is someone who needs $1000, doesn't have it, but is willing to pay more down the road to get $1000 **now**. So the bank loans it (or most of it) to him so now you both have $1000. Sort of. The bank is betting that you won't need that $1000 before the loan is paid off, so seeing a $1000 balance might help you sleep at night, but you don't really *have* it. What you have is money from the future, when the loan is paid off. Of course, it isn't just one customer and one borrower, it is hundreds, thousands, or even millions of customers and borrowers. If your car breaks down and you need that $1000, you can get it, becasue the bank has a lot of customers and they hold a some fo the money back, just in case."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
8n6eyj
|
If almost all counties in the world have an external debt towards another country, couldn't the debt be paid only "on paper", thus getting rid of it?
|
Economics
|
explainlikeimfive
|
[
"dzt5xm9",
"dzt5z8d",
"dzt625k"
] |
[
"In reality, they've issued bond with different maturity dates. So one debt might be payable 30 years from now, another debt only 10 years. They're denominated in different currencies. And governments don't just owe each other, but private investors (like individuals, pension funds or businesses) or international organizations (like the World Bank) as well. Because the real situation is so much more complicated, it takes a lot of diplomacy to get multiple countries to agree to restructure debt in this way. It usually only happens when there is a crisis, and restructuring the debt is preferable to it not being paid at all. This is what happened with the Greek government's debt for example. It's more common for bilateral measures to be taken--like when a rich country forgives a debt that a poor country owes, as a type of foreign aid."
] |
[
14
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
8jfnoz
|
How can some animals have a standard heartbeat of like 200+ without their hearts collapsing?
|
Edit: I mean 200+ bpm.
|
Biology
|
explainlikeimfive
|
[
"dyz9zdu"
] |
[
"Smaller animals have smaller hearts, which means they move less blood with one pump, and correspondingly need to pump more often to move all the blood they need. Of course since their heart is small, it doesn't take as much energy for them to pump. There's actually a pretty close correlation in mammals between the size of the animal, the size of the heart, and the animal's pulse. Mice hearts can beat as much as 800 times per minute, whereas a blue whale's heart beats about 10 times per minute."
] |
[
7
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
6qjee4
|
What makes different peppers hotter than each other?
|
Biology
|
explainlikeimfive
|
[
"dkxpt9p"
] |
[
"The substance that makes peppers spicy is called [capsaisin.]( URL_0 ) It's actually an irritant to mammals, probably an evolutionary defense against getting eaten. Unfortunately for peppers, humans are kinda dumb and like to get high. Capsaisin is mostly found in the seeds of the pepper, the flesh is actually quite sweet. So some peppers have been bred to have less flesh and more seeds, so they are \"hotter\". It's all about breeding, like how some dogs are bigger than others."
] |
[
3
] |
[
[
"https://en.wikipedia.org/wiki/Capsaicin"
]
] |
[
"url"
] |
[
"url"
] |
|
78n9sp
|
What, exactly, is Petro-Yuan and how will it affect the US dollar?
|
Economics
|
explainlikeimfive
|
[
"dov4wwr",
"dov4vxr",
"dov4uke"
] |
[
"It creates an automatic demand for dollars that keeps the value of the currency high. We could produce no exports of any kind, and the money would stay valuable because everyone needs to buy oil, and oil only sells for dollars. It's pretty unlikely that China will make that move in the near future, since devaluing our currency would basically gut their economy...Yuan being cheap compared to dollars is what drives the trade gap between our countries, and they have worked hard to keep that state of affairs going."
] |
[
33
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
89qnp3
|
Cell phone tower radiation. Is it dangerous to live near a cell tower?
|
Technology
|
explainlikeimfive
|
[
"dwsrvvt",
"dwsw46u",
"dwssyqr",
"dwsvcj5",
"dwt3faw"
] |
[
"Cell phone towers emit non-ionizing radiation. This type of radiation is also emitted by televisions, cell phones, microwaves, fish, your mother, and dirt. If one receives a significant enough dosage, the health risk is \"getting a burn\" as this form of radiation, when absorbed, generates heat. Recommend to your mother that she not climb the tower in order to get close enough to be burned and she should be fine."
] |
[
94
] |
[
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
844rzv
|
Why do many workplace PCs still run on old software?
|
Technology
|
explainlikeimfive
|
[
"dvmqt64",
"dvmvukw",
"dvn1vg7",
"dvn0hog",
"dvn0rju",
"dvn7hgj",
"dvmqm98",
"dvn4fj1",
"dvmybod",
"dvmwycy",
"dvnmf16"
] |
[
"A few reasons: 1. Cost. Upgrading software is expensive. If an upgraded licence costs $50 that may not seem like much, but doing that for 5,000 machines gets really expensive really quickly. 2. Compatibility. Very often, companies will have custom or specialized software that may not function well with newer software. If the older software doesn't have patches/upgrades, or those patches/upgrades are not cost effective (see point 1) you may need to keep other software downgraded in order to preserve compatibility. 3. Security/Reliabilty. Older software - particularly in the enterprise - can be more secure and/or stable because the bugs and security holes have been patched. Newer software may introduce newer bugs that can compromise operations. 4. Usability. Not everyone is computer literate in a company and upgrading their software may confuse them to the point where they struggle to do their job until they learn the new software."
] |
[
325
] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
ne6imx
|
How are we able to notice immediately when wearing stereo earset in the wrong side?
|
some stereo earset doesn't have obvious Left Right marking and wear it in the wrong side. But i could immediately notice when playing the music. Do left and right ear has different hearing characteristic?
|
Biology
|
explainlikeimfive
|
[
"gyepone"
] |
[
"When some music of mine was in the final stages of mixing, we were all listening back to one of the songs. There were doubled vocal tracks, one on the left, and one on the right. I told the mixing engineer to switch them around. We all agreed that it was better after it was switched but couldn’t say why that was. It’s hard to know what it was that made me want them switched around. My best guess is that as people who read left to right, we want to hear the sound that happens first (even if only by a millisecond) in the left ear so the music is moving left to right."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
aekasg
|
If you would go into space, and go out of space 12 hours later, would you be on the other side of the earth?
|
Physics
|
explainlikeimfive
|
[
"edpvzj5"
] |
[
"No. Maybe. Depends. This really depends on how you go about going to space. If you just shoot up straight (more or less) that it takes 12 hours to come down again then yes you will approximately be on the opposite side but still on the same hemisphere (so not quite the opposite point). If you add some north/south component to that ballistic trajectory you could hit the opposite point. But if you actually go into orbit then it might not even be possible to hit the opposite side after exactly 12 hour as you might go around earth every 70 minutes to hours or only every few days (although an orbital period that long would also mean it would take quite a while to come down again, too) so the spot you will be at after 12 hours really depends on the orbit."
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
g1en90
|
How does the taste of water differ from city to city?
|
Chemistry
|
explainlikeimfive
|
[
"fnf41xr"
] |
[
"Each cities natural water reservoir has different minerals and what not in them. Plus each place handles the treatment of water in their own way. So each of those little variables tweak how the water tastes."
] |
[
9
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
5xixmd
|
What determines whether you are left or right handed?
|
Biology
|
explainlikeimfive
|
[
"deifdqn"
] |
[
"There was an article posted on here recently claiming that your spinal cord plays a part in it. Sadly I didn't read the article so I can't give you anymore information about it."
] |
[
9
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
ci1din
|
What is that "blurry effect" seen in photographs when an object like a car or a train moves quickly?
|
Technology
|
explainlikeimfive
|
[
"ev0hjr3"
] |
[
"There are many multiple things but the simplest way to explain it would be with exposure time. That's the time the film or light sensors collect light. Since most cameras are digital lets stick to to that. So for however long the exposure time is the sensors collect the information that will determine the color of the pixel. But if something moves quickly then multiple different colors will be collected and in that way cause the blur. & #x200B; That's the simplest way to explain it. Then there is things like focus and more complex parts which I'm not as good in so at its basic think of it that the pixels on the photo are open and collecting light for a brief moment and if there is too much movement they will capture several different points of data instead of what you were expecting."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
6km5uz
|
Why does Russia promote an Anti-LGBT message?
|
Culture
|
explainlikeimfive
|
[
"djn91yd",
"djn4g15",
"djna1rl",
"djn4ono"
] |
[
"I have a russian friend, and it seems to be a general theme that they don't accommodate anything much outside of the typical. If you're atypical it's your problem to deal with and nobody else is interested in hearing about it or accommodating you. I think what's happened is that having generations and generations living in relative poverty there's very much a \"fend for yourself\" attitude. Don't accommodate others - you support you and your kin first and those who can't do that for themselves need to. And its rude to ask people to adapt to your needs and wants. You know how people get pissed off at vegetarians or vegans? (a) for mentioning it all the time and (b) asking people to cater for them at barbecues? It's a lot like that. Russians just get pissed off at gay people the same way again (a) for hearing about it all the time and (b) being asked to adapt for them. There's of course radicals who hate them to a much larger extent, but I get the impression that for the most part that - like veganism - if they never heard about it they'd not mention how irritated they are by it."
] |
[
19
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
cyl4z1
|
why does the falcon rocket seem to explode blue plasma mid flight while other types of rockets do not?
|
Engineering
|
explainlikeimfive
|
[
"eytbmvc"
] |
[
"It doesn't You saw the video with the glowing curves that came off the side of the rocket didn't you? That's the exhaust from the cold gas thrusters on the rocket, it uses those to turn itself The launch took place at just the right time of day that it was dark enough on the ground but bright enough in the sky that you could see the light reflecting off the exhaust of these thrusters. You'll only get this effect for launches around sunrise and sunset, you won't get this reflection during the day(ground is too bright) or at night (it's dark up there too) so it's fairly rare. It's similar to the plume that has been seen after two launches from Vandenberg URL_0"
] |
[
3
] |
[
[
"https://www.space.com/42068-amazing-spacex-rocket-launch-photos-not-aliens.html"
]
] |
[
"url"
] |
[
"url"
] |
|
8fdf81
|
How do insects breathe?
|
Biology
|
explainlikeimfive
|
[
"dy2knga"
] |
[
"Insects (like flies) are covered in small holes called spiracles. They don't have some central breathing center like lungs. The spiracles are the ends of tracheae. Oxygen passes through these tracheae to the tracheole, which is full of fluid. The oxygen dissolves in this fluid and then diffuses throughout the insect's body"
] |
[
15
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
60nkn7
|
How a nuclear detonation work?
|
Also, once a nuke goes off, how is the reaction controlled?
|
Chemistry
|
explainlikeimfive
|
[
"df7t9da",
"df7rtm9"
] |
[
"The atoms of certain elements, such as Plutonium-239, have their nuclei spontaneously fission, producing two smaller nuclei and some extra particles, and those extra particles can make more nuclei fission. If you have a small amount of Pu-239 then most of the neutrons fly out of it without making more fissions, so it's stable. We call the nuclear reactions *subcritical*. But with a larger amount, or if it's compressed, the neutrons cause more fissions and the reaction grows in power explosively, each fission causing several more, we call this *prompt supercritical*. Once it gets started, control over the reaction is basically by momentum and inertia. Nuclear bombs are actually designed to 'hold back' the explosion just for a brief instant so that more of the atoms can fission so the bomb is more powerful. Otherwise the first bit of the blast scatters the rest of the atoms and the nuclear reactions stop having only used a few percent of the fuel. There's fusion too, which is a bit different to fission but the general idea is the same. On a final note, ocassionally a nucleus fissions and some neutrons isn't released straight away, but comes off one of the smaller nuclei later. That time delay is what enables a nuclear reactor to be controlled, it's operated so that those delayed neutrons are needed to maintain a stable critical reaction where on average each fission triggers just one more."
] |
[
9
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
ml0n0a
|
What’s that sour taste before you vomit?
|
Well, I yakked up my oatmeal this AM. Pretty sure part of my burrito from last night too. Fun times. Wish I chose the toilet versus the sink but hey... Anywho - before nearly every time I’ve ever thrown up, I get this sour taste in my mouth and my mouth waters. That’s my cue to find somewhere to puke, quick. So, thanks for the heads up, body but uh...what’s actually happening?
|
Biology
|
explainlikeimfive
|
[
"gtiumfj",
"gtiv1ch"
] |
[
"For me it's salty but it's part of a reaction where your body produces extra saliva to protect your throat and mouth from the stomach acid from what I understand"
] |
[
7
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
i95rq7
|
How do ancient buildings dug up in archaeological digs, end up so far underground?
|
Other
|
explainlikeimfive
|
[
"g1cw4hn"
] |
[
"From a [Science Focus]( URL_0 ) article... > They got buried in the first place because the ground level of ancient cities tended to steadily rise. Settlements constantly imported food and building materials for the population, but getting rid of waste and rubbish was a much lower priority. New houses were built on top of the ruins of old ones because hauling away rubble was labour intensive and it was much easier to simply spread it out and build straight on top. Rivers periodically flooded and added a layer of silt, while in dry regions the wind was constantly blowing in sand and dust. & #x200B; Also, you might find this thread interesting... [Archaeologists are always digging up ancient ruins. How did all of these ruins get buried in the first place?]( URL_1 )"
] |
[
8
] |
[
[
"https://www.sciencefocus.com/planet-earth/why-do-we-have-to-dig-so-deep-to-uncover-ancient-ruins/",
"https://www.reddit.com/r/AskHistorians/comments/17je7i/archeologists_are_always_digging_up_ancient_ruins/"
]
] |
[
"url"
] |
[
"url"
] |
|
7mc9k3
|
Why is mold acceptable in some foods, such as cheese, but not in anything else?
|
We're able to enjoy something like blue cheese dressing, but once mold shows up on bread, it's no good. Why is that? Thanks!
|
Biology
|
explainlikeimfive
|
[
"drswwag",
"drsxl9s"
] |
[
"Some molds create toxins that are harmful to the human body. The molds that cause many types of cheese (such as the blue cheese dressing you enjoy) do not create the harmful toxins. Mold on many other foods don't necessarily indicate danger just a lack of freshness (fermentation happening, change in taste, texture, etc.) and are perfectly safe to eat but if you have other food options you will likely throw it away because you probably have enough money to not eat moldy bread."
] |
[
39
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
g4cnj8
|
Where does dust come from?
|
Biology
|
explainlikeimfive
|
[
"fnwm4vo"
] |
[
"Dead skin cells, hair, random dirt and and whatever else particles from outside, and little particles from things like wood and furniture and rugs. Random stuff."
] |
[
10
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
8ief1x
|
How does our skin shrink/expand with weight change?
|
Biology
|
explainlikeimfive
|
[
"dyr1ep8"
] |
[
"our skin is already quite flexible as proven by people suffering from an illness that affects their connective tissue, making them able to extremely stretch their skin. If you gain a lot of weight your body will recognize the increased stress of that skin in the area and it will create more skin cells and skin for that region. The \"shrinking\" only goes up to a certain extend and takes a lot of time. It happens because your body notices that that amount of skin is not needed anymore so it is an unessecary waste of energy and resources therefore it slowly removes skin."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
crgi0s
|
Why do cigarettes contain so many harmful chemicals? Why are they not just filled with pure tobacco?
|
Chemistry
|
explainlikeimfive
|
[
"ex4sl88",
"ex517lh",
"ex4snef",
"ex5vhps",
"ex6mfd8",
"ex4w3gp"
] |
[
"Most of those chemicals are the resulting products from burning tobacco. There are also binding agents, preservatives, flavorants, and additives that make manufacturing easier, but tobacco is the major contributor to the carcinogenic chemicals present in smoke."
] |
[
93
] |
[
[],
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
g0ukh1
|
Why does visible electromagnetic radiation (light) is easily blocked by an object, but radiation of lower frequency like radio or cellphone signals can easily travel through obstacles to a degree?
|
Physics
|
explainlikeimfive
|
[
"fnbxyf0"
] |
[
"Oooh I knowww this one. TL/DR below. First, EM radiation can be considered a quantum wave. By wave, I mean like a string being jiggled up and down and particles sit somewhere on this string. Think of the string passing through a pair of walls. When wiggled bigger than the opening the wave structure breaks down, this is called diffraction. EM radiation is weird because it acts oppositely to this. When the string is waving smaller than the opening it breaks down when traveling through. More on this in a minute.. Secondly, we consider how we can make the string wiggle within a smaller space. This is considered with wavelength. Larger wavelength is associated with low frequency which leads to longer travel due to lack of absorption (stuff that stops the \"flow\" of the waves). Now, thinking of absorption associated with wavelength and thinking of wiggling the string through the doorway we have to consider what happens when the string breaks down. This is called destructive vs constructive interferences. It happens when the opening (walls gap) is similar, a little bigger, or a little smaller, than the wiggles of the string. When bigger it breaks down (destructive), when smaller or similar size it propagates (constructive intereference = continues to move). Now, let's add some pieces together. Larger wiggles travel further in similar or slightly smaller wall gaps. We finally ask, WHY?? The answer comes down to being similar to waves of an ocean. When the waves are BIG they simply flush themselves around small objects and continue on, sometimes they're big enough to take the items with them, like boats. When they're small, small objects can absorb them and they break down. And that's about it. Above a 5 year old: objects are made of atoms that sit close together. These atoms can only vibrate so much before they require an immense amount of energy to move them any further. The amount of room an atom can vibrate is the wall gap idea. Smaller waves get absorbed between these atoms and as they come in contact with molecules. Larger wavelengths have the energy to push their way through. This is why an object can heat up when put under a lot of sound or how microwaves work. TL:DR light is made up of small quantum waves (like ocean waves) where radios are considered larger waves. Larger waves can travel further than smaller waves because they can move past themselves and other smaller objects. Small waves get absorbed by smaller object. Light is easily absorbed by small molecules where radio waves are not."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
fzc8ei
|
How to graphics card driver updates improve performance in certain games/programs?
|
Do the driver updates just correct errors or does the driver make the hardware do different things based on which game is running to "fix" poorly written game code? I thought a driver is just a way to access the hardware and should work the same for all games. Also why are graphics drivers huge (400MB+ file size for the installer)?
|
Technology
|
explainlikeimfive
|
[
"fn3xixx",
"fn44gxi"
] |
[
"Usually driver updates just patch errors and inefficient bits of code. Since running code takes time and energy, cleaning up inefficiencies can make games run better by making it take less time or resources to calculate a particular thing. As for why drivers are huge... they've got to contain all the code to run an entire video output and all of the calculations underlying most rendering principles, as well as specific optimisations for thousands of games and softwares. That's a lotta code."
] |
[
3
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
bgmjyk
|
Why does soap and other chemicals cause water to form bubbles and why are they in a spherical shape?
|
Physics
|
explainlikeimfive
|
[
"elm3rjq"
] |
[
"The shape is because there is no prefered direction of forming , forces are applied evenly in all direction"
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
hjtmjx
|
Why does insects flip over when they die?
|
Biology
|
explainlikeimfive
|
[
"fwoer7t"
] |
[
"Bugspray causes the bugs to lose control of their muscles, and when that happens the muscles spasm. So their legs start jerking wildly and it causes them to flip over. Normally they would be able to flip themselves back, but they can't do that if they have no working muscles. Eventually the poison affects their ~~lungs~~ circulatory system and those muscles stop working also, then they die. Interesting fact: The Army has chemical weapons in their arsenal that can do the exact same thing to humans. Let's hope we never have to use them."
] |
[
9
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
crxl1e
|
What makes you someone have a naturally nice singing voice?
|
Biology
|
explainlikeimfive
|
[
"exai9y4"
] |
[
"The ability to control air from the gut through the nose and mouth effectively is the usual process of singing, those who can regulate it the best are usually more talented singers, which you can observe in say opera singing or notice in the vibrato, falsetto, baritone of the voice etc that being said, there is still something naturally nice about punk or rock singers too"
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
5mcwq4
|
What is net neutrality?
|
Repost
|
explainlikeimfive
|
[
"dc2lb2e"
] |
[
"It's the concept that your internet provider is not allowed to discriminate between websites. If you try to visit Netflix, they should treat your network traffic the same way they'd treat it if you want to visit Google or Reddit. In other words, they are not allowed to, for example, have a policy that \"when you visit Netflix, we'll slow down your connection, because we have an in-house video streaming service that we want you to use instead\". Under net neutrality rules, they are required to treat all of your traffic as equal. The reason this is a big deal is that: - it prevents the ISP from upselling you different plans (you're currently on the Google plan. We can see you'd like to stream music from Spotify as well. Would you like to be upgraded to our Streaming+ service? It'll only be an additional $20/month\". - it helps competition. If ISP's were allowed to discriminate against specific sites, then they could, for example, run their own streaming service, and then slow down your bandwidth when visiting competing services and suddenly Netflix would be in trouble. Or Microsoft could enter a partnership with your ISP whereby your ISP would give Bing priority over Google's search engine. Any time you try to use Google, they could slow it down a bit, and when you use Bing they might give that traffic priority. Something like that could easily be used by big sites to prevent competition. Say you wanted to start up a new social network to be the new Facebook. Unfortunately, Facebook has *a lot* of money, and they might just go out to the big ISP's and say \"here's a bag of money. Please give our site priority over this new upstart\". Users then get a worse experience visiting your new site, so they stop using it."
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
hmd8s0
|
why predators that eat their pray whole (snakes, lizards, birds, frogs, fish, etc) don't have their insides completely torn apart when they swallow an animal that is still alive?
|
I understand venom, but I've seen a lot of videos of live animals still alive when a venomous snake is killed and cut open
|
Biology
|
explainlikeimfive
|
[
"fx4pupi",
"fx4l2e8",
"fx4n7cg",
"fx4srna",
"fx4moji"
] |
[
"The prey has no easy access to oxygen in there. So is suffocated/dead. But they do, rarely, escape, for example: [ URL_0 ]( URL_1 )"
] |
[
20
] |
[
[
"https://media4.s-nbcnews.com/i/newscms/2014\\_16/322921/140414-centipede-snake-cover-1500\\_1be1d0430c642bf8629853a16666a11c.jpg",
"https://media4.s-nbcnews.com/i/newscms/2014_16/322921/140414-centipede-snake-cover-1500_1be1d0430c642bf8629853a16666a11c.jpg"
],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
9vpiq2
|
Why pockets don't exist in women clothing?
|
Other
|
explainlikeimfive
|
[
"e9e3ab8"
] |
[
"Big Clothing does that to sell us purses. Also, our hips tend to be curvier, making pockets a bit harder to put in. Ladies' clothing tends to fit more snuggly than men's, also making pockets a bit harder to put in."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
71ga0j
|
Why studying/thinking hard gives me alot of sugar cravings?
|
Biology
|
explainlikeimfive
|
[
"dnaldq7"
] |
[
"Your brain uses sugar for energy. So when you study or concentrate deeply, you brain uses up the supply. Your brain then requests more."
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
6fuybn
|
how Artificial Intelligence works in terms of programming?
|
###Fantastic answers from all you guys. THANKS!
|
Technology
|
explainlikeimfive
|
[
"dil89ec",
"dil7zqh",
"dilq2jv",
"dilr33e",
"dil5pdg",
"dil7pi5"
] |
[
"Artificial intelligence is a massive field. Asking how AI works is like asking how animals work. Don't let the down votes dissuade you, though. It's an interesting, expanding field. If you have 25 mins to spare, this is a nice video on the topic: URL_1 Edit: it's worth pointing out that neural networks as discussed in this video are just one field in AI, but I think this a nice introduction to the whole field. Feel free to tell me I'm wrong (with useful links to share!) Edit 2: might as well throw in a link to [carykh's channel]( URL_0 )"
] |
[
202
] |
[
[
"https://www.youtube.com/user/carykh",
"https://www.youtube.com/watch?v=ILsA4nyG7I0"
],
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
kbkha8
|
How exactly do bacteria kill us? Do they use our oxygen or vitamins, or eat our cells?
|
Biology
|
explainlikeimfive
|
[
"gfhxpwe",
"gfi484x",
"gfiftzb"
] |
[
"This depends on the bacteria, I'm sure, but many of them produce toxins. Toxins that kill people. Interestingly, usually our body is actually what kills us. See, our body has to take drastic measures to defend itself sometimes. Measures like intentionally overheating. It does this because, even if its defense measures *could* kill us, surrendering to the bacteria is certain death."
] |
[
17
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
93du1y
|
Those celebrates who earn $500k to $1 million per Instagram post, who actually pays them? and how many posts a day are they allowed?
|
Culture
|
explainlikeimfive
|
[
"e3cgdat"
] |
[
"When you see a character in your favorite cartoon drink a soda that your mom buys at home. That's an advertisment. Now these people on really any creative sharing site may it be YouTube or insta. Have companies come to them because they have a big following like that cartoon we talked about. And when they can get alot of people to view an ad for let's say, a new shirt. They will be willing to pay alot of money. Because putting an ad of television already costs a whole lot more money."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
a1j1en
|
What exactly is data mining?
|
Edit: In relation to people ‘leaking’ content for future changes game developers are making to a game.
|
Technology
|
explainlikeimfive
|
[
"eaq9blv"
] |
[
"Developers often put the infrastructure for DLCs/expansions/whatever into the game before it is possible for players to access them. They do this for convenience, and to make update rollouts smoother. It's way easier to put pieces of something into the game one at a time until it's finished, then flip a switch which lets everyone access it at the same time, than to have everyone download a massive update at once and possibly overwhelm your servers. As a result of this, the data for new stuff often exists on people's computers before they should be able to see it. One of the meta-rules for all of computer science is that if you have physical access to a computer, you are that computer's god and can make it do literally anything. Therefore, data miners can manipulate the game's code through various means to show them the new stuff early, even if it won't function normally. This lets you get textures, maps, skins, etc, out of the game, before you can actually load them in-game."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
5pe5nv
|
What is Cancer?
|
Obviously I know it's a deadly disease, but people only describe it as "shutting down an organ" or things similar. What does it do to the cells that kills them?
|
Biology
|
explainlikeimfive
|
[
"dcqgu8v"
] |
[
"A simple way to see it is cancer cells look like normal cells to the body, and they take the place of them, and replicate slowly replacing more and more of the surrounding cells with cancer. The issue is these cancer cells do not perform the function of the normal cells, so what ever they are on slowly lose the ability to perform the function and the organ basically dies, unable to keep working. There are differant forms of cancer that act a bit differantly, but that's the gist."
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
k43snh
|
Why do beaches have sand while the surrounding areas have normal soil?
|
Earth Science
|
explainlikeimfive
|
[
"ge6jhc1",
"ge6lsgp",
"ge6l1rm"
] |
[
"Answer: Waves wash away dirt and then crunch rocks and shells that remain into powder called sand."
] |
[
6
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
l797qk
|
How do we really know there is no two identical snowflakes?
|
I don’t really know what -illion word to use for how many snowflakes have fallen, but how do we know that out of all of them, no two are alike? (Sorry if flair is incorrect)
|
Chemistry
|
explainlikeimfive
|
[
"gl5dsgp",
"gl5onsq",
"gl5ebtq",
"gl5etpt",
"gl62lps"
] |
[
"The idea that no two snowflakes are never alike is more about explaining a concept and not really about knowing that there have never been two identical snowflakes. It is about representing the amount of variation possible in a thing - really the more complex something becomes the less likely there is for something to be identical to it. Like every molecule of water is identical but there are so many molecules of water in a snowflake that the chance of another snowflake having the same number and placement of water molecules in it is so unlikely that it doesn't exist."
] |
[
107
] |
[
[],
[],
[
"https://www.its.caltech.edu/~atomic/snowcrystals/alike/alike.htm"
],
[],
[
"https://www.guinnessworldrecords.com/world-records/first-indentical-snow-crystals"
]
] |
[
"url"
] |
[
"url"
] |
a8e4ru
|
Why does our voice sound different to us when it's recorded?
|
Biology
|
explainlikeimfive
|
[
"ec9weg6",
"ec9wlfw"
] |
[
"When you normally hear your own voice you are hearing a combination of the sound waves in the air as picked up by your ears but also the internal vibration that your voice makes that is transmitted through the bones in your head. But, when you hear a recording of yourself you only hear the external part, not the internal. So, it sounds different and usually higher pitched."
] |
[
11
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
b1frja
|
why do whales breach so violently? I understand they need to breathe, but putting their whole body out of the water and crashing all of their weight down seems excessive.
|
Biology
|
explainlikeimfive
|
[
"eilacf3",
"eilccmo",
"eild3k8",
"eild63o",
"eilo32u",
"eilxj26"
] |
[
"the impact may dislodge parasites like crabs and barnacles, but the most likely reason is the same reason their small cousins the dolphins launch themselves into the air: it's fun!"
] |
[
23
] |
[
[],
[
"https://en.wikipedia.org/wiki/Cetacean_surfacing_behaviour"
],
[],
[],
[
"https://qz.com/902840/scientists-finally-figured-out-why-whales-leap-into-the-air/"
],
[]
] |
[
"url"
] |
[
"url"
] |
|
89fjnx
|
What is reddit circles and how does it work?
|
Other
|
explainlikeimfive
|
[
"dwqls6l"
] |
[
"I believe it's a social experiment where you have to give the password of your circle to as many users as you can but they can either join it or betray you. And, in that case, I guess you lost."
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
l0jx3s
|
How does the body stay warm?
|
How does our body maintain it's warmth? In such cold weather I ask myself how does my body actually warm itself?
|
Biology
|
explainlikeimfive
|
[
"gjtuccu",
"gjtujdv"
] |
[
"We're warmblooded, which means our bodies actually spend a lot of the energy we get from our food to produce heat. The cells of living things contain mitochondria. These are organelle's, kinda like microscopic organs, that produce the chemical energy that organisms use to power their bodies. Warmblooded animals like mammals have many more mitochondria than cold-blooded animals do. All those mitochondria produce a lot of extra energy, part of which takes the form of heat."
] |
[
11
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
d7rhqm
|
What are earlobes for? Do they have a function (or did they once)?
|
Actually eli4, because this is a question from my 4 year old. He loves finding out how stuff works generally and recently has been interested in all the jobs the parts of his body have. Sometimes I know the answer but today he pointed at his earlobes and asked "What do these do?"
|
Biology
|
explainlikeimfive
|
[
"f13sfjx",
"f159f0e"
] |
[
"They aren't considered to have any major function. It appears they are one of those things that are vestigial (once important to a pre-human species, but no longer useful or usable). It may have been an attachment point for musculature that would allow for fine control of the ear position (like in dogs, for example), but it just can't be known at this point."
] |
[
12
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
dwsm4l
|
What is it in our brain that tells our eyes that we are not constantly staring at our noses or glasses and that we are viewing with a normal perceptive range that all humans have?
|
Example, Optician says you need your first set of glasses as a child, or teenager, or even a young adult. You're not accustomed to wearing glasses of any kind for any extended lengths of time, so what is it says that tells us it's okay to have this material this close to a vital organ? Is it kind of I can see things clearly now so I don't really care kind of thing? Sigh of relief if you will, or is it just something our bodies do naturally?
|
Biology
|
explainlikeimfive
|
[
"f7l5y9h"
] |
[
"Your brain adjusts to make your life easier for you. Your brain learns to ignore the glasses because it knows having them on does not affect your performance, and doesnt want to distract you. Same reason you cant see your nose. Fun fact: Someone did an experiment a while ago where they wore special glasses that turned their vision upside down. They wore them for a few days, nonstop, and one day they woke up and their vision was normal. The brain recognised the issue and adjusted the way you perceived the world to fix it. After the person in question removed the glasses, the world (which was now presented correctly) was upside down for him again, and it took another day or two for the brain to \"remove\" the adjustment."
] |
[
7
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
5pahgk
|
How exactly is data transferred wirelessly? Bluetooth, Radio, Satellite, NFC, Wi-Fi, Li-Fi etc?
|
Repost
|
explainlikeimfive
|
[
"dcpo0ue",
"dcq7iqo",
"dcpp8wv"
] |
[
"Imagine the hose in your garden. Its connected to a faucet. If you open and close it fast enough and in a pattern, water comes out of the other end also in a pattern. Now, devices have recievers and transmitters. These know how to \"read\" and \"write\" patterns respectively. We can now set this up so that certain patterns can mean certain symbols. A collection of symbols can ultimately form an email, a message on facebook, and more complex streams like pictures and videos. in real life, these devices turn on and off at tremendous speeds, and as a general rule, the faster you can turn on and off, the more information you can send in a single time frame."
] |
[
46
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
7nzetg
|
Blowing on boiling pasta water effects?
|
Why does blowing on pasta water before it's about to boil over instantly make the bubbles die down?
|
Chemistry
|
explainlikeimfive
|
[
"ds5vx03"
] |
[
"You induce a low pressure system over the water. It makes it evaporate faster. It also causes the bubbles to expand and then pop. Doesn’t do much to the pasta but does make the water boil away slightly faster."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
bsl1hc
|
Why is it so irresistible to put your feet up when you sit down?
|
Biology
|
explainlikeimfive
|
[
"eoo0yo0",
"eoo0fc7",
"eoo8275"
] |
[
"It removes stress from the back and moves you toward a fetal position. Both can be very relaxing."
] |
[
16
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
604eh3
|
How did so many thousands of diverse languages come to be?
|
Other
|
explainlikeimfive
|
[
"df3kcha"
] |
[
"When left to themselves, languages drift pretty quickly, especially when literacy is low and populations and immobile and isolated. It only took a few centuries for Latin to become French, Spanish, Italian, Portuguese, Romanian, and all the other Romance languages. The drift slows when things start to get written down and distant populations are better able to communicate with one another. When you have a lot of small populations isolated over thousands of years, you get thousands of languages."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
63ljru
|
What are "Protected classes" And what are there purpose?
|
I got the gist of it, they're people protected by law from being discriminated against because of stupid things like sex or race. But what are they for/what's the point? What stops employers from making up any reason to fire someone or a business owner to not sell to them?
|
Culture
|
explainlikeimfive
|
[
"dfv0vtn",
"dfv50c3"
] |
[
"> But what are they for/what's the point? The point is exactly what you said: to protect them \"from being discriminated against because of stupid things like sex or race.\" > What stops employers from making up any reason to fire someone or a business owner to not sell to them? Technically, nothing, but the law isn't stupid. In the US, in most states, in most situations, you are \"At will\" employment, meaning an employer can fire you for (almost) any reason or for no reason at all. So let's say you're a racist employer that doesn't want to get hit with a discrimination suit. You're a genius, so you exploit the part of \"at will\" that allows you to fire people for no reason. So you fire *only* people of a certain race, but don't give a reason. You're not giving a reason, so it's not discrimination, right? Wrong. Even if you are using a non-discriminatory policy in a discriminatory way, that is still discrimination. The courts will look at what you are actually doing to see if it is discriminatory. This is pretty much the reason why \"separate but equal\" was ruled unconstitutional: while *in theory* it was non discriminatory, *in practice* it was very discriminatory. So while you might get away with being discriminatory at a low level, for a short period of time, the longer you behave in a discriminatory fashion, and to a broader degree, the more liable you are likely to be found when someone calls you out for it."
] |
[
13
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
i0izm8
|
why does it happen to be that some music keys have a half step and some don’t. eg. there are c# d# but not e#
|
Other
|
explainlikeimfive
|
[
"fzpotq8",
"fzq0725"
] |
[
"You could have E# as a key, but it wouldn't make much sense. E# is the same note enharmonically as F, and F major only requires a Bb. This keeps the key signature clean and easy to read and perform. The same is true of C#. C# requires 7 sharps for the key signature. Db only requires 5 flats, so why use C# and make the music harder to read? The number of sharps/flats requires is determined by the major scale tones. It doesn't matter if you're in a major mode or using the blues scale. Key signature is designed to make the music easy to read based on the tone, tone, semitone, tone, tone, tone, semitone function of the major key. When you then see accidentals you know you're using a different scale or mode."
] |
[
7
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
6n2tro
|
How come that a negative multiplied by another negative becomes a positive?
|
Repost
|
explainlikeimfive
|
[
"dk6a1ge"
] |
[
"The opposite of the opposite is back to normal. If you turned something inside out twice, it would be back to normal. Same as if you turned it around twice. On a number line, the number 5 is five units to the right. If you do the opposite of that, you go left 5, to -5. If you go the opposite of left five (the opposite of the opposite) you're back at 5."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
8mcyp4
|
Why does a guitar have harmonics only on certain parts of the fretboard/string?
|
Picking/tapping a string to produce a harmonic note. What is the science behind this?
|
Mathematics
|
explainlikeimfive
|
[
"dzmoegh"
] |
[
"First you need to understand the concept of overtones. Let's say you play the open E string. The main and strongest tone you're going to hear is the E note, because that's the main frequency the string is vibrating at. But because the string isn't vibrating at exactly the same speed across the whole string \\(the middle of the string will travel further in the middle of the string than it will closer to the nut or bridge\\) the string will also produce a variety of overtones \\(different frequencies to the main note\\). This is what gives instruments \\(and even individual strings on instruments\\) their characteristic sound. If you play the open top E string on a guitar, you can play the same note at the same pitch by playing the B string fretted at the fifth fret...but even though they're the same note at the same frequency, they sound subtly different...and the reason for that because you're 'shortening' the B string, and the B string has a different mass, so it's producing different overtones. A harmonic is an overtone that is a multiple of the base frequency of the string. For example, if a string vibrates at 100hz, its first harmonic will be 200hz, the next, 300hz and so on. Now, a guitar string has 'dead spots' where the string doesn't move \\(the nut and the bridge saddle\\), and the area it can move \\(the rest of the string\\). When the string is particular thickness and tension it 'wants' to vibrate at a specific frequency \\(the note you've tuned it to\\). If you lightly touch the string at the 12th fret, you're creating a new 'dead spot' on the string, the same as the dead spot at the nut and saddle. Now, because the main frequency, the note you'd get if you played the string open, doesn't have a dead spot at the 12th fret, the main note won't sound. Basically, physics won't allow the string to vibrate at the main frequency... but the harmonic *does* have a dead spot at the 12th fret. In essence, it's like we've moved the nut up to the 12th fret, so while we don't hear the main note, we do hear the harmonic. Basically, what we're doing is cancelling out the main frequency so we only hear the overtones, and at that spot on the string, the only overtone that can be produced is the harmonic. So, the reason we can only produce harmonics at certain parts of the string is because those are the areas where we can create a dead spot that will allow the string to produce an overtone that is a multiple of the base frequency of the string. It's why every string has a harmonic at the 12th fret, because the 12th fret is the halfway point of the string, so by creating a dead spot there, we're halving the length, which doubles the frequency.."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
6ypgkq
|
How does Humira work for plaque psoriasis AND Crohn's Disease AND arthritis?
|
I've seen the drug in commercials for all three.
|
Biology
|
explainlikeimfive
|
[
"dmp70ge",
"dmp4wgr"
] |
[
"All three of those diseases involve overproduction of a protein called TNF-alpha. They are so closely related that's it's not terribly uncommon to find them in the same person (especially Crohn's and psoriasis). Humira interferes with TNF-alpha and so can be used to treat all 3. I hope that someone comes along with a more detailed answer but that's what I've gathered over 8 years of using Humira and other TNF-alpha inhibitors for Crohns and Ankylosing Spondylitis."
] |
[
8
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
cxf9wx
|
How do ancestry tests know someone's ancestry?
|
Biology
|
explainlikeimfive
|
[
"eykpvc1"
] |
[
"They look for certain genetic markers that are shared by large populations. For instance, Europeans have one genetic mutation that allows them to digest milk as adults, and the Maasai of Africa have an entirely different mutation that does the same thing. If I have both of those mutations present in my DNA, then that very strongly implies that I have both European and Maasai ancestors. Not all of these genetic markers actually do anything. A lot of them are large regions of junk DNA that serves no coding or regulatory function."
] |
[
30
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
a4ql7t
|
Computers at workplaces of major corporations warn us that upon logging in, we agree to be monitored. How are we actually being monitored?
|
Technology
|
explainlikeimfive
|
[
"ebgspr0",
"ebgwh9p",
"ebh1kda",
"ebgt62f",
"ebgtulw"
] |
[
"Generally logs are kept regarding what sites each user visits and if you have permissions to download files that's also logged as well."
] |
[
7
] |
[
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
66mmq2
|
[Biology] What happens to our bodies when we "warm up" before working out?
|
Biology
|
explainlikeimfive
|
[
"dgjp52w"
] |
[
"Gets your heart pumping harder and dilates your blood vessels, which gives your muscles a fresh supply of oxygen. This increases their effectiveness, delays lactic acid buildup, makes your muscles more limber, and makes it less likely you will pass out."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
mk6z59
|
- Why are some sea foods cooked alive?
|
Why do things like lobsters and crabs get cooked alive? Does it affect flavor? How come they aren't killed then thrown into cook?
|
Biology
|
explainlikeimfive
|
[
"gte86qh",
"gte8k4h",
"gteerse"
] |
[
"If you boil it alive it’s fresher. Banana fresh from the tree tastes better than Banana that was away from the tree for a long time."
] |
[
8
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
c9jjnk
|
How do cryptic crosswords work?
|
I have discovered them in the past few hours and I already love them. They don’t seem so hard but I am confused by how the people doing them know what kind of clue they are working with. (e.g. anagram, double definition, combined abbreviations, etc) I’m looking for how to identify which kinds I’m working with and which kinds I will encounter thanks.
|
Other
|
explainlikeimfive
|
[
"esz1f7g"
] |
[
"Each clue is in two parts one a straightforward clue the other a cryptic one, however in most crosswords there isn't a guide to which part is which. So a cryptic clue might be - Musical with two soldiers to which the answer is GIGI, Gigi is a musical and another word for soldier is GI or general infantryman. two soldiers means that the letters gi are repeated."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
8kea9f
|
Why are porn studios allowed to use copyrighted characters?
|
Other
|
explainlikeimfive
|
[
"dz6xskc",
"dz6xxk2",
"dz6xykw"
] |
[
"Whether you sell it for profit is **NOT** the definition of \"parody\". You may argue for other reasons that porn featuring those characters shouldn't count as a parody, but the answer is not obvious, and not influenced by them selling it for profit. I'd also guess lawsuits against the parody makers would bring unwanted attention to the content... especially if the copyright owners *lost* so there was not only attention, but the content was still widely available afterwards. So it may not seem worth the risk, or maybe *neither* outcome seems beneficial enough, for a company to legally attack these parodies."
] |
[
4
] |
[
[],
[
"https://en.wikipedia.org/wiki/Campbell_v._Acuff-Rose_Music,_Inc"
],
[]
] |
[
"url"
] |
[
"url"
] |
|
a46lk0
|
How is salt used to make ice colder when making ice cream, but is also used to make ice melt on the roads during snow storms?
|
Chemistry
|
explainlikeimfive
|
[
"ebbxwoa",
"ebbx415"
] |
[
"Should've googled it first... \"Because you're not making the ice colder in the ice cream machine. In both cases your goal is to make liquid water colder, but the reasons for wanting colder liquid water are different. In the case of the ice cream maker, there's always at least a thin layer of liquid between the cream container and the solid ice, so colder liquid water means more heat transfers out of the ice cream and into the liquid water (so the ice cream freezes fast enough to freeze the air bubbles into the mix which is why ice cream has such great texture). In the case of the sidewalks, colder liquid water means more ice melts and flows off the sidewalk and melting continues at lower temperatures, reducing the slipping hazard. \" Found same question on Reddit from a year ago. Sorry."
] |
[
12
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
5tycin
|
Why does driving 60mph on the highway feel slow like driving 40mph on a normal road?
|
Other
|
explainlikeimfive
|
[
"ddpzd01"
] |
[
"Size of the highway vs the size of a city street. Buildings and other objects are farther away from you. That causes the illusion of you going the same speed. I don't recommend it, but drive 60mph on the street, and drive 40mph on the highway. You will feel like a slug on the highway, and you will feel like you are going a million mph. So will the police, and give you a ticket."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
9odfuv
|
Cars have an “idle speed” where the engine still runs even without pressing the gas. What happens when you’re pressing the brake and completely still? How is the engine not harmed since it’s still running?
|
Technology
|
explainlikeimfive
|
[
"e7t6yzq",
"e7t6iuj",
"e7tqmei",
"e7t7ciw",
"e7t6wu5",
"e7tkqxp"
] |
[
"Automatic transmissions have a fluid coupling between the engine and transmission that allows the engine to run at low RPM without transmitting much torque to the transmission. Imagine a propeller spinning, making the fluid spin, then the fluid makes another propeller spin. Manual transmissions disengage the clutch so there's no connection between the engine and transmission when you push the clutch pedal in."
] |
[
173
] |
[
[],
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
exnf4s
|
Why do content creators need 100% calibrated displays? Aren't consumers going to buy non-calibrated, over-saturated displays anyway?
|
Technology
|
explainlikeimfive
|
[
"fga0vqd"
] |
[
"You are right that most consumer displays have poor color accuracy, though more devices are starting to come with calibrated displays. Professional content creators don't use calibrated displays so that you and I see things correctly, but rather to ensure that when working as a team every member sees the same thing. If they were to all use consumer displays then, for instance, you might have someone who's display has more of a green tint and might adjust colors to compensate, but then it would look wrong to the rest of the team and it would be a constant back-and-forth."
] |
[
11
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
5qp5ln
|
How do auroras in the night sky work? How do they form? Why do they occur? Why do they only show up near the poles?
|
Physics
|
explainlikeimfive
|
[
"dd0zmgu"
] |
[
"[Here is an informative video explanation]( URL_0 ) actually aimed at children, so I think it's appropriate for this sub. :) Basically, energy from the sun (solar wind) hits the earth's atmosphere and excites the gasses in the atmosphere until they light up. (This is the same way that neon signs work, and is the reason that neon signs and auroras are the same colors - blue, red, and green.) As for why they only show up at the poles, it has to do with the *shape* of the earth's magnetosphere. If you've [seen a drawing of a magnetic field]( URL_1 ) you may notice that the lines \"connect\" to the magnet only at the poles. Because the earth's magnetic field works the same way, when charged solar particles hit the atmosphere they are directed to the poles of the earth instead of the rest of it."
] |
[
6
] |
[
[
"https://www.youtube.com/watch?v=nHn5OO1t1yc",
"https://upload.wikimedia.org/wikipedia/commons/thumb/1/17/Earths_Magnetic_Field_Confusion.svg/310px-Earths_Magnetic_Field_Confusion.svg.png"
]
] |
[
"url"
] |
[
"url"
] |
|
6q0jqy
|
What's the difference between a permanent and a washable marker?
|
Chemistry
|
explainlikeimfive
|
[
"dktng7o",
"dktnrmw"
] |
[
"Washable markers use substances that are water-soluble--put water on the stain, and it dissolves. \"Permanent\" markers are not water-soluble, which protects them from fading due to natural water exposure--though they are usually soluble in alcohol or another solvent, if you really need to clean them."
] |
[
4
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
a75n2k
|
What exactly is happening when a body part "falls asleep" that causes it to lose all feeling?
|
Biology
|
explainlikeimfive
|
[
"ec0h15x"
] |
[
"You have put pressure on the nerve, disrupting its ability to communicate with your brain. The nerve is the conduit that sends you the sense of feeling. This is often, incorrectly, attributed to cutting off blood flow to the region."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
ar5xic
|
what are the Constitutional mechanisms that give Congress its spending authority, and is there legal precedent around the looming clash between the presidency and Congress on this topic?
|
Other
|
explainlikeimfive
|
[
"egl1vdl",
"egl1di9",
"egl2mau"
] |
[
"Article 1, Section 8 of the US Constitution enumerates specific powers of the US Congress. The first power listed is the following: > The Congress shall have power to lay and collect taxes, duties, imposts and excises, to pay the debts and provide for the common defense and general welfare of the United States; but all duties, imposts and excises shall be uniform throughout the United States The Constitution specifies that Congress has the power to *collect taxes*, and over the course of US history there has been some debate as to how that money actually gets spent. Through various debates and several related Supreme Court rulings, it was determined that the power to *raise* money implied the power to *spend* money. As to the looming clash - the Attorney General of California was interviewed by NPR today, and he and the interviewer discussed an important point. While the President has the authority to declare a National Emergency, the definition of \"National Emergency\" is vague. Therefore it doesn't really matter if Trump admitted that he didn't have to - it's still within his authority to do so. As a result, the Attorneys General of several states are currently studying the declaration to determine from which appropriations Trump intends to draw the additional funds that he wants. That will determine how they build their case against the Administration."
] |
[
31
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
6uikvs
|
Why does diabetes lead to amputations?
|
I'm puzzled why too much sugar in your blood would eventually lead to your limbs turning black and needing amputations.
|
Biology
|
explainlikeimfive
|
[
"dlswq2p"
] |
[
"Diabetics with poorly managed blood sugar have high amounts of sugar in their bloodstream. This causes inflammation in blood vessels, irritating and eventually destroying them. The tiny peripheral capillaries are worst affected. So you end up having bad circulation in your limbs, which can cause cells to die."
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
lroqh8
|
Tax write offs
|
Economics
|
explainlikeimfive
|
[
"gon092h",
"gon42gf"
] |
[
"Yes, you are correct for personal deductions. Write-offs are more in play for people who own small businesses or are independent contractors/consultants, since their taxes are based on revenue - expenses = profits. Take an iPhone as an example... pretty much anybody with a business needs a phone. Rather than needing to earn $1,500 in income to have enough post-tax income to buy a $1000 iPhone that's almost $1100 with sales tax, you instead buy it as a business expense and reduce your taxable income by $1100, actually saving yourself taxes by buying the phone. Same with a car lease, if you use it for business purposes. Or say you're a doctor going to a medical conference in Hawaii, and tack on a vacation with your wife and can deduct many of the expenses for the trip."
] |
[
5
] |
[
[],
[
"https://youtu.be/XEL65gywwHQ"
]
] |
[
"url"
] |
[
"url"
] |
|
o3hkcc
|
Why do the televisions in the store always have amazing pictures but when you get home and pop in your favorite movie...?
|
Shopping for a new TV, this is mild infuriating.
|
Technology
|
explainlikeimfive
|
[
"h2btyoq"
] |
[
"TVs typically need to be calibrated after you pull them out of the box. They look great in the store because they are specifically calibrated to make the demo video used to show off the TV look as good as possible. However, those demos don't translate to every day TV, movies, etc. I usually Google the make/model of my TV plus the key word \"calibration\". You will see several professional review sites that will usually share the recommended calibrations or calibrations they used to test. Now, if multiple sites are saying the same thing for a certain setting, that's what you do. If they vary on another setting, go with the one you like the most. This will give your TV a good baseline configuration and then you can make adjustments from there. Hope this helps!"
] |
[
27
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
adfrkd
|
gyroscopic precession and why 2 blades on a wind turbine don’t work
|
Engineering
|
explainlikeimfive
|
[
"edgirgc"
] |
[
"Two bladed turbines work, and they do exist. In general, increasing the number of blades gives diminishing returns, meaning that increasing the number of blades reduces the amount of power you get from each blade. However, longer blades increase the cost. It just turns out that for large wind turbines, making them with three blades is more cost effective than a two bladed design with longer blades or a four bladed turbine with shorter blades. & #x200B; Gyroscopic precession is the effect that you get when you're moving a spinning object around, like a fidget spinner. Basically, the object wants to keep spinning in the direction that it's spinning, and if you force it to spin in another orientation instead, it's going to try to get back into its original orientation. & #x200B; & #x200B;"
] |
[
7
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
9j9wi4
|
So I know that when you feel something cold or hot, it's your skins particles exchanging their kinetic energy with the particles of the other medium. So how come in space, where there is no medium to exchange heat, your body heat can't just keep you warm instead of instantly freezing?
|
Physics
|
explainlikeimfive
|
[
"e6puf9b",
"e6pthqe",
"e6pv2lk"
] |
[
"First of all, you wouldn't instantly freeze. Secondly, there are multiple ways of transferring heat. You described the process of conduction, which is indeed not possible in a vacuum. However, heat transfer in space is dominated by radiation. All objects radiate thermal energy, and how much and what kind is determined by their temperature. When an object starts to glow \"red hot\" its because its temperature is high enough that some of its thermal radiation has shifted out of the infrared and into the visible part of the electromagnetic spectrum. In space, if you were in the dark, like in the shadow of the earth, you would radiate away heat until you were the same temperature as empty space, only a couple degrees above absolute zero. However, the sun is very hot, and radiates a lot of energy, so if you were exposed to it, you would rapidly heat up to perhaps hundreds of degrees, precisely because there isn't any material to conduct that heat away. This is a major design consideration for spacecraft and spacesuits."
] |
[
29
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
7fzmco
|
How come we get all snotty when we cry?
|
Biology
|
explainlikeimfive
|
[
"dqficr6"
] |
[
"It's a drainage thing. Tears mix with mucus in the sinuses, and this thins out the mucus and makes it run from your nose."
] |
[
7
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
638s6n
|
How can all cultures be equal if some cultures clearly have significant differences in women's rights, minority rights, religious rights, and freedom of expression?
|
Culture
|
explainlikeimfive
|
[
"dfs5c0r"
] |
[
"1. Who is saying all cultures are \"equal\"? 2. How is this person/people defining \"equal\"? 3. Equal != Identical. Cultures and most things in this world are very complex and it's difficult to compare things apples to apples. If you have one culture that's really big on gender/religious rights and other freedoms but has issues with racism, that doesn't mean it's better/worse as a whole than say, a culture that has racial equality but women are treated like shit."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
5vf245
|
Donated human blood only has a shelf life of about 21 days, what happens to the gallons of un-used human blood if it never finds a recipient?
|
Biology
|
explainlikeimfive
|
[
"de1nxq5",
"de1nct2",
"de1jxr6",
"de1o6gs",
"de1nmuh",
"de1p7z0",
"de1otdz",
"de1nshn",
"de1l87z",
"de1s9it",
"de1qvaq"
] |
[
"Also a blood banker. Separated into it's components, some parts last 5 days, some last 42 days, some can be frozen for a year, some can be frozen for ten years and manufactured into other products. We're always looking at ways to extend shelf life. We're pretty crazy about inventory efficiency too, but expired product (usually only group AB red blood cells, or excess platelets which only last 5 days and are harder to manage) are biomedical waste or research material. Biomedical waste goes for incineration. (Edit: So, Group AB, please donate plasma and platelets if you can. Group O people, stick with the whole blood. That way, we can maximize the usefulness of your gift!) Edit, again: For all those who are asking \"I'm type (letter/Rh), what should I do?\" the answer to the question is always changing. Inventory fluctuates and we can get short on any group at any time, so ask your local blood bank, or answer the phone when they call. :) In my geographic area, we might collect about 300 units of blood in a day. Let's say 7 percent are O negative type, as is the case in North America. That's 21 units. A single major trauma or bleeding event can use 40 units of blood. (That's the extreme, though) Just some perspective."
] |
[
1130
] |
[
[],
[],
[],
[],
[
"http://www.deadlinenews.co.uk/2015/07/23/one-in-ten-blood-donations-is-wasted-in-scotland/"
],
[
"http://www.radiolab.org/story/308403-blood/"
],
[
"http://www.allgov.com/news/where-is-the-money-going/selling-donated-blood-is-big-business-in-us-140709?news=853635"
],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
lzfbxe
|
Why do we nonstop smile when we are around and or, interacting with the person we like? On a chemical, or neurological level?
|
Biology
|
explainlikeimfive
|
[
"gq1vg2j",
"gq27vbg",
"gq1vu5u"
] |
[
"Smiling is an expression that is the result of millions of years of evolution. All living non-human primates use non vocal expressions similar to the human smile (showing teeth with a closed jaw) to express submission and joy. We can then hypothesize, especially because people that were blind at birth smile, that smiling is so engrained in our DNA that it is instinctual rather than only a form of complex communication. A smile helps us practice empathy which is a defining trait of Homo sapiens but empathy isn’t unique to our species our ancestors used it for millions of years before we appeared"
] |
[
11
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
6g8491
|
Why is it harder to fall asleep in noisy environments?
|
Biology
|
explainlikeimfive
|
[
"diokbjv"
] |
[
"Humans (and therefore our brains) evolved in a wild environment. Certain noises (or noises of certain pitches or volumes) are associated with various dangers, loud noises are usually signs of threats for example (people shout when scared or hurt), and the sound of rustling leaves nearby could be the sound of a moving predator. Even though most of those threats are irrelevant to you in your daily life these processes are ingrained in the way your brain develops. When you hear these threat noises, your brain reacts, it becomes alert and readies you to fight or run. This alertness prevents sleep because you are vulnerable when asleep."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
6b2w9n
|
How did the iPod Shuffle charge from a 3.5mm headphone jack?
|
I never see any articles mentioning how they charge, everyone is just concerned for it to BE charged. I mean, it would be lit if I could charge my phone through a headphone jack... How does it work?
|
Technology
|
explainlikeimfive
|
[
"dhjdgc2",
"dhjdaf8"
] |
[
"For charging a battery you just need two connections. The headphone jack always has at least two (sometimes more for microphones) It is not common to charge via headphone jacks but nothing restricts you to do so. Apple has built a charger to transfer the electrical energy from 5 Volt DC to whatever the shuffle needs."
] |
[
15
] |
[
[],
[
"https://support.apple.com/en-in/HT201568"
]
] |
[
"url"
] |
[
"url"
] |
j7e2pa
|
Why do we get a "chilly" sensation in our bellies when we get scared?
|
Biology
|
explainlikeimfive
|
[
"g8417bd"
] |
[
"When you’re scared your body dumps something called cortisol into your system. It’s the fight-or-flight hormone and one of the effects of cortisol is that your blood moves away from your extremities to your core, making you feel cold."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
5zkfzu
|
What is the worst that can happen if you turn off the computer when it states "Do not turn off your computer"?
|
Technology
|
explainlikeimfive
|
[
"deyriis",
"deyrkvf",
"deyxytz",
"dez8rrn",
"deyrfjd"
] |
[
"With older OS's you could really risk disk and registry corruption when the computer would lose sudden power, however, with Windows 10, I'm seeing little to no effect. My computer doesn't seem to run chkdsk or anything after losing sudden power, and even my Office365 excel and word applications seem to successfully present me with my unsaved work next time I start them up. Pretty impressive progress, actually. Context? So, I've been a tech for about ~20 years now and I've worked with all versions of windows going back to 3.11 (ahem). My cat insists on using my computer tower as a means to gaining access to the kitchen counter and he REGULARLY hard powers off my computer by doing so. (I'm running Win10 home)."
] |
[
36
] |
[
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
o0ze3k
|
why does glass absorb infrared and ultraviolet light, but not visible light?
|
Physics
|
explainlikeimfive
|
[
"h1y1qty",
"h1yiiho",
"h1yc6ho",
"h1yl21k",
"h1ynr04",
"h1zjdr3",
"h1yl7im",
"h1ykkum",
"h1yw6aj"
] |
[
"It has to do with how light interacts with matter. To absorb light, you need to have things work just right. You may have heard that light is quantized, what this means is that it only gets absorbed in specific chunks, one photon at a time. And all the energy of that photon has to go somewhere. It turns out there are a few different places for that energy to go, and since each color of light has different energy, those different absorption mechanisms affect the colors differently. Ultraviolet has the highest energy, it’s absorbed into the electrons in a material, kicking them up in energy or ejecting them from the atoms entirely. Infrared light is absorbed into the vibrations of the atoms and molecules in a material. For glass, visible light isn’t high enough energy to be absorbed by the electrons and too high to be absorbed as a vibration. Remember, it’s all or nothing - you can’t absorb half a photon. It gets a bit more complicated since you also have to absorb the momentum of the photon, and not matching the quantized momentum kick will lead to the photon not getting absorbed either. Different materials have different thresholds for these absorption methods, and a huge difference is whether things are metals or not. Metals have completely different architectures for their electrons, but the basic concepts of “need to absorb a whole photon” still apply."
] |
[
1717
] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
8317q5
|
How do potholes form in a road, and why is tar used to fill them instead of asphalt?
|
Engineering
|
explainlikeimfive
|
[
"dvecoy6",
"dvedgl6"
] |
[
"Car wheels are like 500 lb rolling hammers, and truck or bus wheels are even heavier. To say vehicles 'pound' the road is an understatement. Over time, heat, cold and water cause cracks in the road surface. Water and debris make the cracks worse over a few weeks or months. When the crack is large enough that a car's wheel might even fit a little inside, then every wheel that goes over it could take a chunk out. Depending on traffic and weather, this can turn a small crack into a dangerous pothole in as little as a few hours. Asphalt is mixed with rock and uses a tar-like substance to hold the rocks together. It's more work to lay asphalt than just the tar by itself, and tar on its own more easily flattens. Often, repairing a pothole is just temporary until the entire road can be repaved. Again depending on traffic and weather, this can/should be done about once a decade, more or less. (Small infrastructure budgets and small towns notwithstanding.) Potholes don't damage the road all *that* much because the thing that actually does the work of carrying the weight of cars and trucks is actually a thick gravel layer underneath the asphalt: the surface just keeps those rocks dry and protected from things moving them around."
] |
[
18
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
kkw62w
|
Why is buying prescription pet food such a PITA? It's **food**. I've had an easier time getting myself a prescription for opioids filled.
|
Other
|
explainlikeimfive
|
[
"gh4y7gy"
] |
[
"I just went to google prescription pet food and the first bunch of articles talk about how they're mostly bullshit. But apparently you can buy online because there's no actual pharm in the food. That's my 2 minute of research expert opinion."
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
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