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lwxxzm
|
Why are car's external temperature reading so wildly inaccurate for the dust few minutes of driving?
|
Edit: first, autocorrect changed it to dust 50F out, I get in my car and it's reading 64F out, drive for 5 minutes and it's reading 50F. Why is this?
|
Technology
|
explainlikeimfive
|
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"The sensor is traditionally located somewhere on the bottom of the engine compartment. It has to be outside of the main body of the car, and it also can't be above the engine or it would pick up engine heat as it rises. The problem then is that it's really measuring the temperature of the road. If you happen to be parked on a clear black driveway that's picking up a lot of sun, it might read hot. If you're on a snowy driveway and you haven't seen the sun in weeks, it might read low."
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5
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lwybne
|
Why is it dangerous to break the sound barrier?
|
What is it about breaking the speed of sound in a medium (which *seems* like a random, unrelated thing) that can cause physical damage to an object traveling through it?
|
Physics
|
explainlikeimfive
|
{
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"The speed of sound is the speed at which air molecules can move out of the way. Think of it like you’re wading through a ball pit. The faster you move, the faster the balls shuffle out of your way. But there’s a limit here - eventually you’re plowing through so fast that the balls stop moving out of the way in time and start crumpling into eachother instead. Supersonic aircraft have a similar problem - rather than flowing around the aircraft the air begins to compress in front of it. This generates heat and disrupts the air flow over the flight control surfaces. If you’re unprepared for this, your plane may rattle itself to pieces or lose control.",
"There is a region of speed called the trans-sonic, a little below and a little above the actual speed of sound where, for various technical reasons, the air flow around an aircraft becomes extremely turbulent compared to other slower or faster speeds. The turbulence can disrupt the control and lifting surfaces of the aircraft and cause them to behave unexpectedly. While we were still figuring out how all this worked that lead to aircraft being lost due to them tumbling out of control and breaking up from the extreme forces they experienced.",
"Let's first break down what the speed of sound is. Sound is the way matter moves as a giant block. Imagine you had a mile long broomstick and you pushed it at one end. At a molecular level, you've actually pushed the first layer of molecules, which push the next, and the next, and so on. The movement of the stick actually propagates at the speed of sound. It's no different with actual sound -- you're just pushing air with a particular pattern to it. That air pushes more air, which pushes more, and so on. So now let's go back to that broomstick. If you keep pushing the broomstick, the molecules in it keep pushing the ones in front of them. But what happens if you push them as fast as they can push the next ones? Well, the next ones can't quite get out of the way in time, so you end up building this pocket of molecules that need to get out of the way of your push. The same thing happens if you're in a vehicle approaching the sound barrier. You're trying to push air away as you go through it, but that air can't push other air out of the way fast enough, so it builds up. You end up with a dense pocket of air right outside your vehicle that you have to push through. When you finally break through, all that air has to go somewhere. All that air that built up can only move out of the way so fast, so it all moves at the speed of sound away. The important thing here is that all of that energy is going to be pushed away all at once, and it's going to be pushed away at a constant speed. This basically creates a very high pressure wall that is going to push things really hard when it reaches them, creating the destructive effect of the sonic boom."
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lwyj0s
|
- In the vast company empires of our world today, how do you grow a company from your garage to the multi-thousands of people and billions in costs/revenues? For example Amazon, Microsoft, google? It’s mind boggling to me.
|
Economics
|
explainlikeimfive
|
{
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"You convince rich people in Silicon Valley to give you money. No seriously. Most new companies emerging today on a truly grand scale receive their money, funding, and a lot of help from Venture Capital and Investment funds, along with just plain super wealthy people, generally based in Silicon Valley and the SF Bay area. These people invest in newer, smaller companies, and invest gigantic, hoping to see absolutely bonkers return on their investment. Any of these new companies could be the next Google or Uber or Facebook, and if you get in early, and invest enough, you'll be Scrooge McDuck rich. You can grow pretty quickly, when an investor says: Here's $100M. Just grow. Don't even try to make money, just grow Which gets us to the next step. Unlike other businesses, these companies are expected to not make a profit. You running a lemonade stand need to make a profit or you're out of business. This company does not, when they are running low on money, they just ask for more, and its expected they just get it. They are expected to spend wildly just to grow, and profits will come later (hopefully!). What if someone gave you money to operate a chain of lemonade stands, a blank check, and told you \"don't even worry about making money\", I mean, you could put a lemonade stand on every block and basically give away lemonade for free huh? Makes it easy to grow. Essentially what a lot of these companies are trying to do, is setup that lemonade stand on every corner and worry about money later.",
"You start a business that does something either way better than anyone else has done before, or sell a new idea in a way that the masses can appreciate. For example Amazon, it was started by Jeff Bezos by selling books online, it was really the first of it's kind, a place to buy things on the internet. People started buying books from Amazon, and Bezos used the money to grow the business, by expanding the range of things sold, upgrading the site, hiring more employees, etc, which in turn brought more people to Amazon.",
"Use the \"sharing economy\" to create an unregulated version of an existing industry. Think how uber disrupted taxis or what air bnb is to hotels."
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lwzl1r
|
How the hell does South Korea have a larger economy than Russia?
|
Economics
|
explainlikeimfive
|
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"Russia's economy is almost entirely dependent on the price of oil and natural gas. They don't really have too many other meaningful exports, and their domestic service industry BARELY meets domestic demand at BEST, over the past few years the Russian economy has also been actively shrinking as oil and gas prices lower, and as other countries have put sanctions on them, cutting them off bit by bit from the global market for putin's various misdeeds, so no money for Russia. South Korea on the other hand has a VERY robust tech industry and actively exports tech products all over the world (samsung!!!) and is not economically dependent on the price of a natural resource. Because of its robust tech industry and domestic service industries, South Korean workers are more economically productive, and produce more wealth for their work time",
"Russia has 145 million people and a natural resource based economy. A lot of Russia is rural and pretty much dirt poor. South Korea has 50 million people and an advanced manufacturing economy. The country is mostly urbanized. South Korea has Samsung, LG, Hyundai, and a few other very large corporations.",
"They produce a lot of good technology and have two global automobile brands. Russia really doesn't have anything beyond oil and gas. It has a lot of talented people but it's hard for Russian companies to grow into global household name brands because it's hard to find foreign investors and trade partners (people aren't too trusting of the Russian scene).",
"You are looking at nominal GPD, meaning all of the GPD is giving in USD and that any variation in trading of currency would affect this number. For GDP nominal South Korea have an economy 1.083 time bigger than Russia, but if you look at GDP PPP (purchasing power parity) you will see that Russia have an economy 1.75 time bigger than South Korea. So the actual economy of Russia is bigger, but if you exchange the value of the economy of both countries in USD then you would get more USD from South Korea. But that's just because of currency trading. Of course Russia also have more people than South Korea so if you really want to have a image on how wealthy or not the citizen of each countries are you are better off looking at GDP (PPP) per capita. In that case South Korea have an advantage of 1.61 times that of Russia. This just mean that the population of South Korea is more wealthy in general than the population of Russia."
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lx077z
|
where is my cloud storage based? Like physically?
|
Hey ELI5! I was wondering today where the physical storage for cloud storage is. Like actually located? For specifically OneDrive from Microsoft
|
Technology
|
explainlikeimfive
|
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"In some data center, somewhere, and for redundancy reasons, likely in more than one location. So what the hell are these? Basically they are just immense warehouses on some random plot of land somewhere, often times they are in more rural areas or places with low cost of real estate or low electricity costs (they use a ton of power, to both run the computers and for cooling the site).",
"So Microsoft owns a bunch of datacenters all over the world. These datacenters are basically a warehouse chock full of servers and hard drives (well, increasinly solid state drives but that'sabother issue). \"The cloud\" consists of datacenters like that regardless of the service. Most major companies have more than one, while smaller companies are renting space in someone else's datacenters like amazon's. Those with multiple like Microsoft will store your data in a regional datacenter near you, with backups for that data both locally and in physically distant centers in case something like a fire or flood wrecks that whole datacenter. The methods for choosing a datacenter as the primary location for your data varies. For example Microsoft does a degree of specialization for different 365 platforms. You'd access a storage specialized facility for onedrive and sharepoint while other centers focused more on processing power handle things like the web applications of microsoft office. In different countries and regions the level of differentiation/specialization varies. Frequently some sort of algorithm based on the most used IPs for your account or the IP used to create it is used to select the nearest appropriate datacenter. The exact methodology for determining all of that is proprietary and a bit opaque, but the jist is that it's probably in a warehouse just outside a major city somewhere in your general region.",
"Expanding on the existing good answers, [it's likely going to be in at least one of these buildings]( URL_0 ). Whichever one is closest to you in network-distance is a good guess, and probably at least one other one for redundancy.",
"It's physically located on storage that is connected to the cloud servers. In the case of all major cloud providers, they have servers and storage in datacenters all over the USA and in some cases international. Ultimately though the data is stored on HDDs and SSD drives.",
"\"The cloud\" is just someone else's computers that you use. Where those computers are depends on whose cloud service you are using and where you are. Microsoft has ten major datacenters in the US running cloud services, on the coasts and in the middle of the country. So if you live in Texas your data is likely in San Antonio. But they also replicate data between datacenters in case one goes down, so your data could be at any of them.",
"Most cloud-based storage is redundant. Google, MS, Apple etc have lots of datacenters around the globe. These datacenters have compute resources that access a Storage Area Network (SAN), which is basically a whole bunch of hard drives bundled together and put on the network. Your OneDrive document would be processed by the compute resources, which will store 2 or more copies on various SANs (typically geographically distributed, for example one in New York and one in Los Angeles so that a natural disaster doesn't take out both copies at the same time). The SAN itself also has [redundancy]( URL_0 ), so that a failed disk does not wipe out the data on the SAN (and with the number of disks we're talking, failures are frequent -- somebody's job is to walk around the datacenter replacing disks all day)."
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"https://en.wikipedia.org/wiki/Standard_RAID_levels#RAID_6"
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lx0q9n
|
What do countries need armies for?
|
Other
|
explainlikeimfive
|
{
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"Which war did you think was over? There are many wars going on right now. They just don't involve your home country yet, whichever that is. The question you raise is a noble one, which has been raised by many before you, but it is very naive as well. Short answer: If you are defenceless, someone will come and grab all your stuff, or make you serve him. If you refuse, he will hurt you or kill you, as an example to others who want to refuse. So that's why any society needs to protect itself with a military."
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9
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[
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[
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lx1ek8
|
Why do paper sheets that come in a stack stick together and two different stacks don't merge together easily?
|
I have a pack of ruled writing paper which tends to stick together in an aligned manner even if I, say, dropped the stack from a small height (all punched holes and edges are aligned). Whereas, if I try to put two stacks on top of each other and carefully align their holes and edges, when i drop the superstack, the both stacks immediately seperate out, while maintaining their own respective stack alignments.
|
Physics
|
explainlikeimfive
|
{
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"You've got a small amount of air trapped between the layers. If you let the stacks sit for long enough, they'll \"meld\" back together and act like one stack."
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3
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[
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lx1m1r
|
How do camera stabilizers work?
|
Technology
|
explainlikeimfive
|
{
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"There are two main types of camera stabilizers. The simple version has the camera on a rod that can move freely and weights at the other end. The more weight, the more movement is dampened between the handhold and the camera. Gyro stabilisers like the ones for hobby drones or for mounting cellphone cameras on use a sensor that detects movement, the sensor sends signals to a computer built into the gimbal, and the computer activates electric motors that counter the movement of the hand."
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3
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[
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[
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lx1mar
|
how do banks make money???(moreover how do islamic banks make money as they dont have interest?)
|
Economics
|
explainlikeimfive
|
{
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"Banks make money from charging fees for services, and charging interest on loans. You put money in a bank account, the bank loans that money to your neighbor to buy a boat. Your neighbor makes payments plus interest and the bank is now earning money. They also invest in other things but the large drivers in consumer banking revenue are service fees and interest payments. Islamic banks charge fees still.",
"Well you already answered the first question. Interest. The bank has a bunch of depositors money. And rather than let it sit in a vault, they lend it out to profitable ventures and charge interest rates. That’s their profit. Yes. Much of Islam, and most of Christian history too, usury, or the charging of interest, was for it by religious law. This is why there is a historical association with Jews and the profession of banking, they had no such proscription against interest for loans to non-Jews. So if you needed a loan in medieval Europe, a Jewish banker was your best bet. Christians have simply dropped their religious proscription against usury. Many sects of Islam use Islamic banking where interest isn’t formally charged but a fee is ascribed to a loan. The fee is typically what interest would have gotten. The lender will still make a profit off of the loan and the borrower isn’t technically paying interest. And yes this is a technical BS hand wave but that’s what they do. They just call interest something else and presto chango their god isn’t upset with it apparently. Islam isn’t the only religious tradition with these workarounds. You should see what weird lengths conservative and Orthodox Jews go to on Saturdays to keep kosher with all their weird ancient laws.",
"So people are are fucking misleading you. Banks--especially the larger banks-- make the majority of their profit via investments in the financial markets and corporate lending. People here are talking about taking low interest rates and such and making money and thats not wrong, but its misleading. They basically make their money by doing investment activities, including organizing large-scale corporate loans (which are more like an investment than a loan). These account for a bit less than half their revenue, but the margin on this activity is much higher and can account for 60%-70% of their net profits. Your general consumer banking, lending, service fees and such, generally only account for around 20% of net income, despite bringing in a lot of revenue, the expense of operating these services is just much higher and their profit margins are quite low. Not that its not good, its just that you have to have really large scale to start making money here, especially to compete with how much effort goes into this activity. It means you have to have TONs of accounts to operate huge, to really make this valuable. A lot of banking consolidation is around this factor. It just makes more sense to be bigger. Islamic banks, without interest, of course, can be involved in investment activities too. But for general loans, the interest is already calculated in to the total loan amount. So instead of pay principal + interest, you just start with a higher principal and have no interest. Its completely just sleight of hand, you pay interest, they just don't call it interest."
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4
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lx1mpd
|
Why does a stiff neck persist for days after you slept in a bad position?
|
Why does the stiffness and the pain stay there for a while? What's the body trying to achieve when you've already woken up and gotten out of that bad position?
|
Biology
|
explainlikeimfive
|
{
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"Your neck was already bad to start. The poor sleeping position just kicked it up a notch. You probably have a pinched nerve. Sometimes, you just have to wait those out. A bath or shower helps. A little bit of heat goes a long way. Then go buy a better pillow. Pillows are the best thing. You want one that raises your neck up so that you're spine is straight from head to coccyx. You might have a bad mattress too. I find that harder mattresses work better than soft ones. Stretching every morning, the second that you wake up, really helps. Light stretching, nothing too intensive. Bottom line, your neck or back is misaligned in some way. Sometimes it takes an X-Ray to see where the problem is. I fixed mine with exercises and stretching but everyone is different."
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lx1x95
|
Why do employers require years of experience for entry level positions?
|
Other
|
explainlikeimfive
|
{
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"text": [
"They don't want to pay what a trained person is worth but they also don't want to train someone.",
"Follow-up question: Why do employer's require a Bachelor's degree when they are only willing to pay $12.75 an hour?"
],
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6
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lx1yib
|
Why do we never run out of music?
|
Other
|
explainlikeimfive
|
{
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"text": [
"I suppose it has something to do with the permutations and combinations of various notes, tempos and spaces. This is all assuming you stick to a 12 note scale. I imagine other cultures use different pitches for their scales creating way more than 12. You combine all those possibilities and you have countless varieties of undiscovered “music”. Sure, not all will be pleasant to listen to. You might find that many songs end up sounding similar, have similar chord progressions, similar melodies etc but again you just need to change one of those things and it becomes unique instantly. And with time, tastes change, instruments change adding even more variables to the mix. Where dubstep/electronic beats would have sounded unpleasant and grating around 50 years ago, it’s something people enjoy now as we crave newer experiences.",
"Because of the complex unlimited resource we have in music. Let’s divide music in 3 section melody, beat, an lyrics. Musica can be creat with only one section, or only 2 section, or with all of them together. Lets get melody: we have 12 tones/keys (C,C#,D,D#,E,F,F#,G,G#,A,A#,B). In each tone we have the major scale and minor scale, Each scale has 7 notes. And/Or each scale have 7 chords. But, they arent the only scales we have. We have plenty more scales. Now, a song is an art, like painting. We can play one chord forever like “tomorrow never knows” by The Beatles, or we can play as many chords as we want like many songs by Beethoven, or “just” by radiohead, or Karma Police. So, just with melody we can make unlimited songs. Imagine same chord progression with different lyrics. Lyrics is another thing that cant be counted. Besides, we can also add the many languages we have. Now, lets get the beat, the beat can make a whole other song out of the same melody and lyrics. Im going to stop here, cuz i guess we can guess how infinite the world of music is.",
"Fundamentally, music is sound frequencies. Mathematically, there are infinite combinations and permutations of those sound frequencies, which we call music."
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lx212o
|
Why do some clothes start smelling bad when they come in context with outside air?
|
Chemistry
|
explainlikeimfive
|
{
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"text": [
"This question is puzzling to me because it doesn't describe much about what you've observed. Some fabrics, particularly natural fibers will retain odors depending on the age and the manufacturing processes. For example when wool is damp it can have a smell resembling wet dog. Older wool or wool which has undergone additional steps in manufacturing will be less likely to smell. What I'm wondering is if you are washing your clothes incorrectly - leaving them to sit in a damp pile before laundering, washing them on a very short cycle, using too much detergent or fabric softener, leaving the clothes in the washing machine for any period of time before drying, line-drying inappropriately (overly crowded lines, materials doubled over on themselves too many times etc.), storing clothes away before they have fully dried, or if your washing machine is in need of a cleaning cycle. If you leave clothes wet for a period of time, say 24 hours or more depending on the ambient temperature, your clothes will develop a musty odor due to mold growing in them. This smell will persist through washing, especially if you allow the musty smell to build up and/or if you do not air your clothes properly. If you leave your washing to sit for a long period of time after washing then it will also get musty, the same applies to inappropriate/incomplete drying. If you use excessive amounts of detergent or fabric softener then this can accumulate a tacky or almost waxy buildup that then traps dirt and other stuff which contributes to odors in clothes. Washing machines will be able to strip this stuff away over time however if you are using too much each cycle then it will only accumulate. If your washing machine is left with the door/lid closed then the moisture in the barrel can develop musty smells just like with the example above with wet clothes. Check your seals and other nooks and crannies for buildup or any signs of mold/mildew. If you have soapy or waxy buildup then that's a good indicator that you're going overboard with detergent/fabric softener. Give the washing machine the hottest, longest cycle available and use products or instructions as recommended by the manufacturer. Repeat if necessary. This will help with mold and mildew but once it's in seals and things like that then it's extremely difficult to eliminate and your best option is to clean it throughly and then manage it well (leave the washing machine door open to air out, wipe out the seal especially if it's a front loader and get rid of any excess moisture you can find). If you are using too much detergent in your clothes then you should find that soaking them in warm water overnight will likely discolor the water slightly and you might be able to get suds out of the soaking water too. This test only works with older clothes which do not leak dye into the water, however. Likewise, if you do this test and the water becomes murky or takes on a brownish tinge (or it even becomes sort of greasy) then you need to wash your clothes more regularly and on a full cycle/with a pre-wash cycle added. The reason why you might not smell that characteristic musty smell until you are in fresh air is because your house and/or your clothes all vaguely smell of it. Your nose rapidly becomes accustomed to smell so it will tune out most smells after a short period of exposure (this is why you can stop smelling pizza at your movie night even at the very moment you're eating it but then when you go to bed and wake up the next morning you can smell the vague odor of pizza lingering in the air.) Another reason is that the mold that may be in your clothed isn't producing a lot of odor when it's cool and the clothes are dry but when you put them on the clothes warm up and you will naturally produce some sweat. That combination of heat and moisture reactivates the mold and it can begin growing (and stinking!) again. Heat will also cause the chemicals that make smells smelly to get into the air more. These aren't the only reasons why it could be happening but they are common ones. Do you notice that your gym clothes or socks/underwear have a distinct smell after washing and drying (even if you need to smell them up close)? If so, it's most likely an issue with how you do your laundry. Also, final thought: some fabrics are more or less resistant to growing mold and developing musty smells, and some fabrics are much more likely to \"take on\" these smells and hang onto them in a similar way to how a thin dishcloth only absorbs a little water but a thick sponge can absorb a lot and it can hold onto that moisture for a long time."
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3
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|
lx34dz
|
How Does the grass not die after being covered in snow for months?
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gpkn4a6"
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"text": [
"It goes dormant, same as it does in the summer if you don't water it. The chlorophyl parts die off, since limited/no photosynthesis, and the plant lives off stored energy reserves until spring."
],
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6
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[
"url"
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[
"url"
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|
lx3rua
|
Why do humans have children at any time of year, but other animals only mate in the Spring?
|
Biology
|
explainlikeimfive
|
{
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"text": [
"Many animals have shorter gestation periods than people, so they get their little babies out earlier in the year when it's still easy to walk about and hunt and raise their kids and get them set up with some food before wintertime when food becomes harder to find. Humans don't have that problem since we are used to living in a conditioned shelter and having access to food year round.",
"I had livestock for some years and we bred our goats in the late fall and they delivered in spring. Some animals have longer fertile seasons than other as well. Coyotes where I live breed from January to June. Mice can breed any time of year once they are mature.",
"Humans are pretty weird compared to a lot of mammals. Many mammals are very well aware of when females are ovulating and often both males and females will only attempt sex during this time, which might be a few days a year, but they have a very high success rate, so can reliably bring about babies right in time for spring when food will be plentiful. Humans have mostly concealed ovulation - even females have limited ability to detect exactly when they’re fertile, and males have even more limited ability, and on top of that even when correctly timed breeding success rates are very low compared to most mammals. There are a lot of theories about this but they generally center on the enormous resource demand to raise a human to adulthood, where females will want some assurance that they’re going to have some help, so our reproduction is set up to strongly encourage long term sexual relationships with an emotional bond to improve the odds that at least two adults will be around to help raise offspring. Part of this favors many chances at successful reproduction year round, with the challenges most animals would face from a winter birth being offset in part by technology available to us."
],
"score": [
6,
3,
3
],
"text_urls": [
[],
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|
[
"url"
] |
[
"url"
] |
|
lx4afw
|
Is it just a coincidence that the color spectrum "loops" around?
|
May have worded this poorly, but when you look at the color spectrum, it appears (to me, my thinking may be flawed) to be the primary colors red, yellow, and blue and their intermediates. Red to yellow with orange in the middle, yellow to blue with green in the middle, and blue to what would be red, with purple in the middle. Except there is no red at the end of the natural spectrum, just at the beginning. So is it just a nice coincidence that it wraps around perfectly?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gpkv3cp",
"gpkzat1",
"gplaaxa",
"gpl2z9e"
],
"text": [
"Actually it doesn't loop around, but due to some clever hardware exploiting our visual sensory organs, it can be made to seem that way. In our eyes we have 3 types of sensors, reacting to (grossly) simplified red, green and blue. The bands of the sensors overlap slightly giving us the ability perceive 'colors\" of the spectrum as ratios of stimulation in each band. By having 3 light sources corresponding to the center frequency of each sensor, we can generate the perception of any color simply by varying the intensity of those three light sources. By modulating them with 3 sine waves 120 degrees out of phase, you can get the effect of a color wheel that perfectly loops around.",
"The sensation of colour is generated in our brains, as a way to interpret the signals from the cone cells in our eyes. The cone cells come in three different types, sensitive to different wavelength ranges of light. When light of a certain wavelength hits the retina, it stimulates the three different types of cone cells by different amounts. Those different amounts of stimulation are sent to your brain, where you brain assigns a \"colour\" to the combined signal. As it happens, light of the shortest wavelengths we can detect, around 400 nanometres, our brain interprets as \"violet\", while light of the longest detectable wavelengths (around 750 nm), our brain interprets as \"red\". The fact that red and violet seem to be similar colours that can blend into one another comes from the fact that our brain also needs a way to interpret a *mixture* of wavelengths, some around 400nm plus some around 750nm, with no intermediate wavelengths. If you have a mixture of 400nm plus 750nm light, your brain gets signals from the short wavelength and long wavelength sensitive cone cells, but *none* from the middle wavelength cone cells. Your brain interprets this as magenta - a colour \"in between\" violet and red. Magenta cannot be generated by a single wavelength of light - it's not in the rainbow. Your brain needs to be able to move continuously from violet to red via this magenta sensation, to account for different ratios of short+long wavelength light. So your brain considers this to be a continuum of colours fading smoothly into one another. **In summary:** No, it's not a coincidence. But it's also not an inherent \"fact of nature\" that 400nm light looks \"similar\" to 650nm light. It's a result of the architecture of our eyes and brain. For example, birds have extra cone cells sensitive to ultraviolet light. To them, 400nm and 750nm light most likely look very different, and the wrapping around in \"colour\" only occurs for the wavelengths around 250nm (in the UV where we can't see) and 750nm.",
"It doesn't. This is why Magenta isn't a real color. It's a composite of wavelengths from opposing ends of the spectrum.",
"That's just your brain messing with you. When it sees red and blue light, but no green, the brain knows something is up because if it would be some color in the normal range between red and blue there would be some green in it. The absense of green tells the brain it has to be something else so it has to be purple. A lot of how we perceive color depends on the brain and on what it expects to see. Humans basically have 3 different types of receptors for light in different colors (with some overlap), usually called blue green and red (although that isn't really accurate because each of them detects a range of colors and they have overlap) but based on how stimulated each of those receptors are, the colors will be interpreted. A strong signal on the receptors that react strongly to blue but a weak signal on the receptors for green and red makes it look blue, etc."
],
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43,
15,
3,
3
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|
[
"url"
] |
[
"url"
] |
lx4fqh
|
Why are Greek letters used as variables in math?
|
I.e. θ, Σ, Δ, etc.
|
Mathematics
|
explainlikeimfive
|
{
"a_id": [
"gpkvrrb"
],
"text": [
"1. The ancient Greeks did a lot of very important math. 2. You run out of letters quite quickly. Two-letter variables usually aren't used because they could also mean a multiplication of the two single-letter variables that were used somewhere else. That's why people use Greek characters."
],
"score": [
11
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
lx4ygv
|
Why does pinching your nose change the way your voice sounds like?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpkyew3",
"gploqpq"
],
"text": [
"Sounds is just vibrations in the air, so when you pinch your nose the part of vibrations that go out of your nose that make sound stop, making it sound different",
"The way air vibrates in your oral and nasal passages determines what your voice sounds like. When you pinch your nose, air can no longer flow through that passage, so it changes the vibrations. This is similar to how if you cover one of the holes in a violin's body, its sound will change. Covering the hole changes how air vibrates inside the violin."
],
"score": [
4,
3
],
"text_urls": [
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
|
lx5n42
|
Why do arms and legs move in opposite of each other when walking or running?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpl3fm5",
"gpln12f"
],
"text": [
"Balance and counterweight. Swing the same arm forward as the leg you are moving seems to make it easier to fall. Also no one other than Elaine can walk like Frankenstein and dance like an alien.",
"To counteract the rotation your legs produce. As one leg goes forward and the other backwards it produces a torque in your hips around your upright axis. Moving your arms the opposite counteracts this torque and keeps you more stable. Try it on a trampoline. Move one arm up above your head and the other down by your side. Jump up high (careful not to add any torque yourself from the jump), then spin your arms around in opposite directions. You will start turning around your upright axis, and end up facing the opposite direction."
],
"score": [
8,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lx6h97
|
Why do batteries deplete very slowly over time when they're just sitting in the pack not being used?
|
I only recently realised that batteries (like AA, AAA, C, D, etc.) have a best before date when I accidentally bought an out of date pack and couldn't figure out why it they wouldn't work! Why do they lose charge, despite not being connected to anything, or one another?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gpl9msq"
],
"text": [
"Self-discharge is a phenomenon in batteries in which internal chemical reactions reduce the stored charge of the battery without any connection between the electrodes or any external circuit. Self-discharge decreases the shelf life of batteries and causes them to initially have less than a full charge when actually put to use. Self-discharge is a chemical reaction, just as closed-circuit discharge is, and tends to occur more quickly at higher temperatures. Storing batteries at lower temperatures thus reduces the rate of self-discharge and preserves the initial energy stored in the battery. Self-discharge is also thought to be reduced as a passivation layer develops on the electrodes over time."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
lx6s2l
|
If pills dissolve in liquid then how do pills with liquid on the inside not dissolve on it self?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gplec4x",
"gplb2ew",
"gplehme",
"gplw6u8"
],
"text": [
"Pills with liquid on the inside are made with a coat that’s nonpolar, whereas the liquid inside is polar (think of water and oil and how they don’t mix). That means that the liquid is incapable of dissolving the coating.",
"The water in the pill is going to have the medicine itself heavily dissolved in it so that the water is \"full\". It can't dissolve any more. The saliva in your mouth doesn't have as much dissolved in it, so it has more \"room\" to dissolve the pill. That's my best guess",
"The liquid capsules are made out of gelatin. This is soluble in water, so will dissolve in your mouth or in your stomach. The liquid inside will contain little to no water so that it can’t dissolve the gelatin from the inside. A similar principle are the liquid tablet’s you put into your washing machine to wash clothes. These are made of a water soluble ‘plastic’ but the liquid inside has very low water content. If you leave them in a humid environment for too long, they will eventually fail.",
"Not every liquid dissolves things the same. Pills dissolve in *water*, not just in any liquid. The liquid inside those pills isn't water."
],
"score": [
28,
27,
12,
11
],
"text_urls": [
[],
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[],
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|
[
"url"
] |
[
"url"
] |
|
lx7tmh
|
Why do anti particles destroy regular particles, and what make them different from other particles?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gplj6mf"
],
"text": [
"First you need to think of anti matter(and matter) as waves more than as particles here. When you have 2 or more waves in the same 'place*' you can no longer consider them individually but instead need to look at them as one single wave that is the combination of the 2. This is just like how sound waves or water waves combine. Second you need to understand that all matter and anti matter have a few basic properties that make them what they are. These are things like electric charge, spin, and chirality. These numbers tell you all you need to know about what the particle is and therefore what their respective wavefunctions are. For now lets just look at charge. Anti matter has the unique property that these numbers are simply the opposite of its matter counter part. So for a particle of chare -1 its anti matter counter part has a charge of +1. This would be something like an electron and positron. So now lets combine a matter particle with its anti matter counter part. What we have is a new wave(particle) with a combined charge of 0. Our new wave cannot be an electron or positron since charge is conserved and is not present in the combined wave. So we must have something new and in this case a pair of photons is the most likely out come of this interaction. Anti particles annihilate matter particles because that is the only(likely) out come to a interaction involving said particles. *place in the everyday physical sense is misleading but close enough."
],
"score": [
3
],
"text_urls": [
[]
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}
|
[
"url"
] |
[
"url"
] |
|
lx80wj
|
How do rain clouds defy gravity?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gplhnik",
"gplhpkv",
"gpllbt0",
"gplkegv"
],
"text": [
"They don't. They form high in the atmosphere from water vapour that's risen due to being hotter than the surrounding air. Then when they cool down, their density rises to the point that it's now heavier than the rest of the air, and they fall to the ground in the form of rain.",
"They dont. We live in what is technically a fluid atmosphere, in that fluid physics apply. So dense stuff sinks and light stuff floats. Everything on our planet, making up our planet, and our atmosphere are trapped here by gravity. But, when water evaporates it becomes less dense than the surrounding air and rises. Over time water particles bunch together in clouds, but remain less dense than the atmosphere below them, so they keep floating. When those particles group together and become big, they become to heavy to float, fall, and become rain/snow/hail/whatever.",
"Contrary to what many people believe, clouds are not vapour, they are not gas, they are liquid. They are formed from vapour that has condensed into microscopic liquid water droplets that are attracted to one another to form different types of cloud. In really high clouds they even freeze and form solid ice crystals. The reason they stay in the air involves a bit of math. As soon as the droplets form they start falling due to gravity. Every body that falls into a fluid (like Earth's atmosphere) will find resistance (due to air drag) and achieve a maximum velocity called terminal velocity, V. The terminal velocity V of a sphere with a radius R (a droplet in this case) is close to 100,000 times R squared. So if you take a droplet of radius R = 0.005 mm (an usual size for the droplets found in clouds) you get that V = 100,000xR\\^2 = 2.5 mm/s. Now you have to think that in our atmosphere we have hotter air below and colder air above. This creates convection air currents, wind currents that go up. So at the same time we have droplets falling at about V = 2.5 mm/s, they are also being pushed up again by this ascending currents, so the clouds keep bouncing and floating up and down these currents most of time. Eventually though, more vapour arrives at the cloud coming from the evaporation of oceans and lakes and rivers, and the droplets get bigger and bigger. Whey they get big enough that the terminal velocity exceeds the ascending winds velocity they fall as rain.",
"What the other commenters didn’t quite mention is that the air has weight. The clouds aren’t sinply floating, they are like a pillow laying on top of a bed, it’s not that there’s no gravity it’s that the bed is simply heavier and holds the pillow up. A standard cumulus cloud weighs around 1.1 million pounds but each square inch of air is about 14 pounds, so all the air between the cloud and the ground plus the entire width of the cloud would be near billions of pounds, the cloud just doesn’t sink through that since it’s lighter and most importantly *less dense*"
],
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10,
8,
5,
3
],
"text_urls": [
[],
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|
[
"url"
] |
[
"url"
] |
|
lx8iiz
|
Why is any executive of a publicly traded company who owns stock not committing insider trading?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gpll274"
],
"text": [
"Executives at these companies absolutely cannot trade their own company's stocks like regular people on a day to day basis, they are highly regulated specifically so they do not, nor will give any impression they are committing insider trading. Executives often can only buy or sell stock at specific times, such as right after an earnings report, where its assumed that all information is publicly available, so they don't have insider knowledge. Another method is that they can schedule (usually about a quarter in advance) buying or selling shares in their own company. They can't predict the price it will buy or sell for that far in advance. A third method is that the executive simply will not have access to buy/sell stock in their own company and their assets in that company are managed by a third party on their behalf. In addition to all of this, they may also be restricted to the types of buys/sells, options, warrants or other types of investments they can make, both in their company and others. Companies, investors, regulators are very aware of insider trading and there are a lot of protections in place on executives to prevent them trading on non-public information-- however, you also do have to allow balancing that out by allowing them the ability to manage their investments, even in the company they work for."
],
"score": [
26
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lx8rq7
|
When you stub your toe, why does it take a bit before the pain kicks in?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpluux5"
],
"text": [
"The body has several different types of pain receptors and they are generally divided into two categories: fast and slow. Fast pain is transmitted via myelinated A delta fibers and is described as sharp, localized pain. The pain travels at 6 to 30 meters per second. Think of a burn or a cut and how quickly one is able to realize this pain and respond to it. Slow pain is transmitted via unmyelinated C fibers which is often described as dull, aching, throbbing. Most often associated with joints, muscle tissue, tendons. Velocity of slow pain is 0.5 to 2 meters per second. This is a very simplified explanation. The action of stubbing your toe involves blunt injury to the skin and more significant trauma to the tendons, muscles, joints. You're receiving pain from your C fibers which is why there is a bit of a pause before you feel the pain. Unless you stubbed your toe on a piece of furniture which had a pointy thumb tack sticking out of it which pierced your toe at the same time--then you would activate both your A delta and C fibers. You'd get the rapid pain followed by the deeper slow pain--slow follows fast."
],
"score": [
5
],
"text_urls": [
[]
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}
|
[
"url"
] |
[
"url"
] |
|
lx8wnx
|
When we get hurt why is our reaction to touch/grab the area that hurts?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gplne0y",
"gplz61c",
"gplqi9k",
"gplohtl"
],
"text": [
"Like a double edged reaction. 1st part is to protect the area from further pain and the second as a primal emergency medical need like clutching a more major bleed in an attempt to stem the blleding (to stop what is inside from getting outside) We want to protect ourselves from further damage and we want to limit the damage already done to us.",
"In addition to things other people have said about why it's a reflex, applying mild pressure over the area can actually lessen the pain. This is because the nerves that detect the pain in your skin can actually interfere with the nerves next to them. This helps them tell you exactly where an injury is. If 3 nerves cover the area that is injured, but the impact was right in the middle causing it send a slightly stronger pain signal than the other 2, it dampens the signal coming from the other 2 to increase the difference in signal and allow the brain to more easily pinpoint where the strongest signal is coming from. Applying pressure over a larger area (like putting your whole hand over where a bee has stung you) can cause this interference so that the nerves at the site of the impact don't send quite so strong a signal. Please forgive me if that's hard to follow - I took physiology 5 years ago and it's much simpler with diagrams!",
"To check what's going on, it could be a bug or animal bite or a particularly sharp stick. Touch lets you tell what it is so you can react appropriately. The faster you have this info the faster you can react, so reflexively grabbing the area in pain makes sense.",
"A question like this doesn't have a definitive answer. We can't know what exactly lead to us do something like this, we can only spectate based on what we observe. That a possible reason would be to put our attention to the injury to make us assess it and treat it in whatever way we might be able. You feel it and assess it. Is it bleeding? Is there a large wound? Is there something continuing to injure you like some stinging insect or such? So touching it assures your body it is being tended to and releases endorphins to ease the pain to allow you to do so with less pain to distract you but enough to ensure you know itnis still injured."
],
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12,
9,
3,
3
],
"text_urls": [
[],
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[],
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}
|
[
"url"
] |
[
"url"
] |
|
lx93lu
|
Why does metal feel cold or wet?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gploazg",
"gplqnwf",
"gplomup"
],
"text": [
"When you touch something you aren't feeling its absolute temperature, more the speed at which heat energy is being transferred to or from your skin. Metals are good conductors of heat, so energy is transferred quickly from your skin to a cold piece of metal.",
"We actually have no specific sense of wetness - our nerves can't detect wet, our brains just work on context, so coldness, if it's slippery or makes our clothes heavy etc. That's why cold things feel wet - you literally can't tell the difference by just touch. Metal conducts heat away so it gets colder,",
"Metal conducts heat extremely well. 99% of the time you're the warmest thing in the room. When you starts something metal that is room temp, your body starts transferring heat to the metal that is colder. Things like wood/paper/styrofoam/plastic arent great conductors of heat energy. So when you grab that book that has been sitting at room temperature, you trransfer your heat into the book much more slowly."
],
"score": [
12,
3,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lx94lc
|
Why do we sometimes wake up, say a bunch of random/nonsense stuff, and don’t remember it?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpm5r73"
],
"text": [
"When you sleep, you enter a phase called REM, or 'Rapid Eye Movement'. It's that point in your sleep where your body essentially reorganizes the messy clutter in your brain to, amongst other things, store memories. This is the deepest point of your rest, so you need time to rise to a light sleep before you wake up in the morning. **So,** if you go to bed too late, your body won't have enough time to get back to that light sleep mode and you're left waking up sort of groggy or hit the snooze button. Your brain isn't ready to be active for another 12 hours, so it's sort of switched off."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lx9e2c
|
Where does money lost in currency exchange go?
|
I purchased something in GBP last year. As I'm Australian, my bank converted the GBP cost into AUD and deducted from my account. A year later, I have received a refund of that item. The company refunded me the cost in GBP (exact same) and my bank has converted it into AUD to deposit into my account. Problem is, due to changing exchange rates, I have lost ~$40 AUD from this purchase/refund, although the purchase and refund in GBP is exactly the same. I may be incorrectly thinking of money as matter or energy - cannot be destroyed - so that $40 AUD must be floating around somewhere in the global economy? Please ELI5 - who has my $40?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gplqjcx",
"gplua8q",
"gplqpe7",
"gplr26t"
],
"text": [
"Money can absolutely be created or destroyed. That’s the primary function of central banks. Nobody “has” your missing $40.",
"You lost $40, and somebody made $40, these transactions preserve almost all the money (except for fees and the like). In the first transaction, the GBP < =AUD rate was higher than the weeks later GBP= > AUD rate. In the first transaction you bought GBP from someone (unknown to you and the bank thanks to electronic exchanges), so you could give the seller their GBP. In the second transaction, your bank sold some GBP to get AUD to put in your account. That transaction was at a different rate, and the buyer got \"a better deal\" than you did in the first transaction. They got your $40, as extra profits.",
"You can’t transfer GBP into AUD. they’re completely separate currencies, from different banks. You can’t spend GBP in Australia, or vice versa. What you can do though! If you want to buy something from here in the UK (for which you would have to use our currency, the pound) is find someone who wants to buy something from Australia, and who has pounds, but wants AUD. Luckily in real life, your bank does this for you, and the forex market is there to show how much AUD you can swap for GBP and back. So when you bought the item, originally, the AUD was performing better, against the pound, then it was when you got the money back. It’s not that you lost the money, it’s just that what you were swapping, your Australian dollers, isn’t worth as much, compared to the pound, as it was before. Now that’s not necessarily a bad thing! It has lots of benefits like making exports cheaper, and isn’t a reflection of the status of the country, the USD is worth less than the pound for example. But yeh generally speaking you’re definitely absolutely wrong about money being like energy haha, it can be created and destroyed a lot, and often is!",
"It's gone. Money is created and destroyed all the time. Most modern money is fiat currency, meaning they get their value from a government accepting it. It's not backed by a concrete product. This means that things and services are worth as much as people agree they are worth. Governments use a variety of strategies to influence the value of money, including trade policies, taxes, wages, setting interest rates, creating, and destroying money."
],
"score": [
7,
4,
4,
3
],
"text_urls": [
[],
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|
[
"url"
] |
[
"url"
] |
lx9u9b
|
How can you replicate the feeling of falling from high altitudes in a nightmare if you have never fallen like that before?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gpltizj",
"gplw3it"
],
"text": [
"It's in our natural instinct to avoid falling from high places they tested this with babies too, even though babies don't have life experience, they'd start reacting uncomfortably when the experimenters made it feel like they were about to fall hence we're hardwired to subconsciously avoid that/know its bad and twitch when it happens in our dreams",
"You've fallen. A lot. As a toddler as an adult, the sensation of falling is something everyone had experienced."
],
"score": [
7,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lxa3we
|
: If you are missing some body parts, will blood travel quicker or produce less?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpluroo"
],
"text": [
"Blood will travel at the same pace because that's dependent on how fast your heart beats in addition to blood pressure. Depending on what parts are missing, the production may be less because there's less body parts that are helping produce blood."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lxak2s
|
feeling of everything being far away
|
So when i was younger and still now very rarely, i would suddenly feel like the walls were super far away, and i would feel like i was in the middle of a boat in a black endless ocean, it would scare me so much l would start sobbing and occasionally i would also imagine and hear my dad yelling at me. I have no idea what this is, i was wondering if someone experienced something similar?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gplxzw8"
],
"text": [
"You just described how it feels when I have fever dreams. Minus the whole “your dad yelling at me” part"
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
lxamui
|
Maybe explain like I'm 1 years old... Just read an article on a team of researchers who recently created a video of a Space-Time crystal. Pls can someone explain in the most basic way possible what a time crystal is? I've read previousposts on this and I still don't understand :(
|
Link to article is [here]( URL_0 ).
|
Physics
|
explainlikeimfive
|
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"A crystal is a material whose internal structure is a highly ordered geometric pattern. So, like a regular crystal's atomic structure repeats in space, a \"time crystal\" is an atomic structure that repeats in *time*. It's a set of atoms that seem to go change between several different configurations and do so in a loop that repeats forever. I really don't know how that works, at all",
"This isn't a simple subject so don't worry if you don't fully understand it. Most people probably don't. Simply put it is a structure which in its ground state oscillates in time instead of space. To start simply a crystal is basically a structure with a repeating pattern. As you move through the structure you come across pieces of it at regular intervals. So a crystal repeats in space, a time crystal repeats in time. It is able to change regularly between different configurations or arrangements of its structure while in its lowest energy state. Lowest energy state means the energy isn't able to be used for work, meaning you can't use the energy or withdraw it from the crystal. When these crystals are acted upon by an outside frequency, let's say an energy pulse hits it, they resonate, or change configuration of the structure, repeatedly back and forth between these configurations, but not in the expected symmetric way. They break symmetry. For example instead of one pulse of energy repeating back through the crystal as one pulse, back and forth between configurations, it may repeat as a fractional pulse, the value of which depends on the structure of the crystal. In a perfect time crystal the changing back and forth should likely continue indefinitely. I don't think they can make perfect ones though.",
"From my understanding this is basically a metronome. It’s a crystal that moves on the atomic level in a patterns at regular intervals. So this could be used to measure time extremely accurately. A lot of times you see that a watch has quartz in it and that is because quartz is a crystal that is used for measuring time."
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lxbbn4
|
Why is lithium so important for electronic vehicles?
|
Technology
|
explainlikeimfive
|
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"Electric vehicles, unlike internal combustion engine vehicles, cannot generate power on demand. They have no fuel to burn. Instead, they must be charged and must store energy for when they need to drive. We use batteries to store energy. We're much better at generating energy than we are at storing it. Batteries kind of suck. The best batteries we can build at an industrial scale are ones based on Lithium. They're very easy to recharge without harming the battery and tend to have a longer lifespan than many others we could build."
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"url"
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[
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lxbl12
|
how come despite being straightened via braces or invisaligners, our teeth always naturally want to shift back, even if the original position was full of spacing or crowding?
|
I know for some of us who don’t have naturally straight adult teeth that the way they grew in pre-treatment is technically *our* “natural”, but why do they still want to move back even if the original position was excessively spaced or crowded? Wouldn’t the ortho treatment make the teeth more “comfortable”, for lack of a better term?
|
Biology
|
explainlikeimfive
|
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"One of the current theories about our jaws is that our jaws are significantly under developed due to our diet. If you look at ancient skulls, and protohumans the jaws are much more pronounced. This is because we spent much more of our days chewing tougher foods so our jaws and muscles developed to be much larger than today. So in that sense modern humans have evolved like a Persian cat or a bulldog with a flat and deformed face. Despite having small jaws our teeth are still programmed to grow as if our mouths were much wider so they come out crooked because there isn't enough space for them. That's why in orthodontics they often remove teeth to make more space. Our jaws just aren't big enough to support all those teeth. This theory also helps to explain a lot of chronic breathing and respiratory problems like Sleep Apnea. Our throats and sinuses are too small because our jaws don't develop properly. That and orthodontics might be making the problem worse by forcing our teeth and palate up and back into our mouths while our bodies are still growing. If this theory proves to be correct then orthodontics are taking the wrong approach, fixing a symptom (crooked teeth) rather than the underlying problem (too small a jaw and palate)."
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[
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lxbpzi
|
If muscles are made of cells, how do parts of a cell move?
|
Biology
|
explainlikeimfive
|
{
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"Muscle cells can be visualized as long tubes with a string running through them. The tube is attached on one end. The string is attached somewhere else. The inside of the tube has \"hairs\" on it. When the muscle contracts, it pulls the string into the tube by bending those hairs to drag it in. This reduces the length of the muscle. When the muscle relaxes, the hairs let go.",
"You mean inside the cell? A lot of it is transport proteins. Cells also have little fiber like threads running through them called microtubules that the proteins use like catwalks. [Here's a good short video showing it.]( URL_0 ) [Here's a longer one showing and explaining more.]( URL_1 )"
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lxckzi
|
If you fall asleep at 8pm and wake up at 4am with 8 hours of sleep why do you feel extremely tired by 10am, but if you go to sleep at 11pm and wake up at 7am you can stay up all day without feeling very sluggish? Does it have something to do with waking up while it's still dark?
|
Biology
|
explainlikeimfive
|
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"This most definitely isn't something universal? I go to bed around 8-9 and get up at 4 every day, and I'm never tired at 10am.",
"Depends on your circadian rhythm (sleep cycle is a circadian rhythm.) A circadian rhythm is essentially your body cycling in tandem with the sun, so every 24 hours. Some people for example are \"night owls,\" their natural sleep cycle tends to be early hours of the morning (2-6 am) until 10am-2pm. A theory behind why people are night owls is that in the hunter gatherer societies some people would have to stay awake to alert the tribe to any predators or other threats. Which of course increases the likelihood of the tribe as a whole to pass on their genes. It's been argued that it's a remnant of those times. Most people however have a natural sleep cycle, which is the classic 10-11pm until 6/7 pm. That's mostly due to us evolving to not be nocturnal. In essence, having people with different sleep cycles, helped protect the tribe. One study showed that Europeans are far more likely to carry the gene. This could possibly be due to how far North Europe is. For example, London is further North than the vast majority of Canadian cities, yet it's one of the most southern British cities. That means that in December day light is a little over 6 hours long. Which means there is far more time where the tribe would remain vulnerable.",
"i go to sleep at 6am since i work nights, wake up around 11-13 most days and feel great, i can start to feel tired around 4-5am sometimes which is just before the light starts to rise. But i also go to sleep with a movie playing and can see the light outside the curtains and have no issues"
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lxd24w
|
How do shower sponges make there be so much more body wash than if there wasn’t a sponge?
|
for example, a small squirt if used directly on your arm will only be able to clean your arm, but that same squirt if put on a sponge can last your entire body?
|
Other
|
explainlikeimfive
|
{
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"If you got wet, put that squirt on your arm, then avoided the falling water as you spread the soap all over your body, it would be nearly as effective as using the sponge. It’s all about being able to distribute it before the water washes it away",
"good suds are made of 3 things: soap, water, and air. If you scrub with just your hand and some water and soap on your skin, it doesn't fluff up the bubbles as much, whereas as sponge adds lots of air to the soap and makes lots of bubbles, so it lasts longer!"
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lxd9hf
|
When do our brains stop/start perceiving something as music?
|
For example, if I played a song really, really slowly. Say, one note per hour, I doubt people would be able to recognize it as music and have the same chemical, physical, and emotional response than if it were played “normally”. When does music become just sound and vice versa? **Have there been any experiments on how slow music can be before we stop “feeling” the music?**
|
Other
|
explainlikeimfive
|
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"You can search Adam Neely on Youtube. He covers a lot of music stuff and some of it from an academic perspective as well. One of his videos talks about this particular question and the answer he gave (or the research gave) is 33 BPM, if I am not mistaken. So if the \"music\" is slower than one beat every 2 seconds, approximately, it doesn't connect together like music anymore and is perceived as individual sounds.",
"You took that question in a different direction than I expected, which made me think of [Sorites Paradox]( URL_0 ). > A typical formulation involves a heap of sand, from which grains are individually removed. Under the assumption that removing a single grain does not turn a heap into a non-heap, the paradox is to consider what happens when the process is repeated enough times: is a single remaining grain still a heap? If not, when did it change from a heap to a non-heap?",
"Experiment or art - you be the judge. The current performance of [As slow as possible]( URL_0 ) by John Cage is planned to last 639 years.",
"Fun(and slightly unrelated) fact: there’s brain injuries that cause sensory issues known as agnosias, in which we lose the ability to process a certain type of sensory input. For example, there’s an agnosia where the people affected can no longer perceive music. Specifically music. This implies that there is a part of our brains that has specifically evolved to perceive music. Music is that important. More on topic: I think this one depends on the song. If I heard a G sharp, no matter how slow the next note was in coming, i would recognize Welcome To The Black Parade.",
"The simplest answer is when you perceive enough of a pattern to what you are hearing to make what has happened to be familiar and to be able to have some idea of how it will continue. Another post mentioned a performance of \"As Slow as Possible\" being done on an organ in Germany. This would fit, not because you can perceive the changes in the melodic line as music, but you will hear the ongoing sounds as a drone. Listening to anything that repeats, with or without some variation, will start to sound like music when the makeup of the repeating pattern becomes clear. RadioLab had an episode where they talked about the premier of \"The Rite of Spring\" which used chords that didn't fit in the tonal vocabulary of the day. Most of the audience didn't enjoy the piece, and legend has it that a duel was fought over whether it could be called music the next day. Polychords are commonly used in music, both classical and popular, today and people don't have the reaction. They talked about how the unfamiliar sounds caused the tension reaction, but now that it is just another tool, people don't react the same.",
"Music major here. Defining something as \"music\" can be considered subjective based on culture/geography. But for most Westerners, when we begin to hear the ratios of frequencies within a monophonic (only one note at a time) phrase, I believe, our brains tell us \"this is music\".",
"Can I just say sometimes the question is more interesting than the answer. A very thought provoking query.",
"I think it depends on what you think music is. The composer John Cage made a piece of music entitled 4'33\" which is 4 minutes and thirty three seconds of silence. It's said that he was inspired to create the piece after an experience in a sensory deprivation tank: A special chamber where you float in water and can't hear or see anything outside your body. Apparently in the chamber you can hear your blood pulsing through your veins. When the piece is performed in front of an audience there's also naturally going to be some sound from them. So people say the music in that piece is the sound of your blood going through your body or is the sound of the audience. But then a lot of music has pauses of intentional silence that doesn't have the intention of a person listening to the audience or listening to their blood in their veins. So if music can be sound and silence we might look and say that it's organized sound and silence. But then there is music that's known as generative music which is purposefully random. And then there's the idea that music is made by a performer and then heard by a listener. Some music composers want their music to make you feel a certain way or make you think a certain way. Others want their music to tell a story. So I think usually music tells us something about the composer and the performers as well as something about us. But when we think of who they are and who we are and see that everything is connected, I think any piece of music is really a window and a mirror at which we can look at the whole universe and ourselves. I think that's really the definition of art. So maybe the best I can say is art with a focus on sound. But then this is a human definition. Birds and whales sing. It's their way of communication, but we think of it as song. They have no intention of it being art but we can see it as such."
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lxdo6h
|
Hospitals and snake bites
|
Do hospitals just like know about all snakebites or is it part of like a special doctor training or do they just have like a snake expert doctor on staff. Do they have all the anti-venoms readily available or do you need to go to a special snake hospital.
|
Biology
|
explainlikeimfive
|
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"It's often a regional thing. Hospitals will have anti-venoms in stock for the types of poisonous snakes known to be in that area. Not all Hospitals will have anti-venom, just like not all hospitals are equipped to deal with heart surgery. The health authority will try to set it up so that there is anti-venom available within a reasonable distance of all populated areas but that's not always practical. In some cases they will have arrangements with suppliers and facilities so that anti-venom can be sourced quickly if required, or they use a helicopter to move a patient quickly. The specific type of snake usually has to be identified to ensure the correct anti-venom is used. There are specialists in this field, but ER physicians will all be trained in snake bites. There's basic training for all Doctors on the subject, and more specific training for Doctors in known danger areas. For example since the chances of running into an Arizona snake in New York are virtually nil, New York hospitals won't carry that particular anti-venom. But they will likely have a pathway to get some if required.",
"Any hospital can provide antivenin. If you can identify the snake they can give you the correct antivenin. It’s ideal if you can provide a photo of the snake or take the snake with you to the hospital.",
"Am doctor in Australia. All emergency department doctors are trained to manage snakebite, and we have anti venom available in the Emergency Department for all of the snakes you might encounter in our local area (two different anti venoms). Never try to catch or even identify the snake - it only puts you in more danger, and it doesn’t make a difference to your treatment."
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lxe2c4
|
Why is it okay to eat food products from old rotten milk e.g. sour cream and cheese, but you can't eat milk itself that's gone bad?
|
Biology
|
explainlikeimfive
|
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"Food we make from old milk (sour cream, cheese, yogurt, etc), we control what kinds of bacteria, mold, or enzymes are put in it, and then \"grow\" the new food in a controlled environment, therefore keeping out the random things that might make us sick. When milk goes bad in a our home, usually it's a mystery as to what exactly invaded and decided to settle down, and usually it's more than one thing. Chances are, one of the many new organisms now growing in your milk might make your GI tract unhappy.",
"Dairy products are not made from \"old rotten milk\"; they are made with fresh milk and sanitized equipment. Yes, the final product is fermented, sour, mouldy, whatever - but it was made that way with particular organisms. The milk in your fridge is old and basically contaminated by a variety of undesirable moulds and bacteria.",
"Spoiled milk is a cesspool of various bacteria. Cultures like sour cream, cheese, etc are monocultures of specific bacteria or groups of bacteria that isn't harmful to humans.",
"There are millions of different kinds of microorganisms that can spoil food. Some of them can be dangerous, like E. Coli while some of it can convert the food into a different, but still edible food, like beer yeast. If you leave your milk out, you might get acidophilus yoghurt by chance, but you probably won't.",
"You technically can, it’s just unpleasant. No, really, sour/lumpy milk is technically more or less safe to drink- just disgusting taste-wise. The reason it doesn’t just turn into cheese is because cheese and sour cream and yoghurt are all made under more carefully controlled conditions than a half-empty jug of milk that’s left to sit in your fridge.",
"I am taking a course on cheese making! When most dairy products are made we pasteurize the milk killing most of the bacteria “good” and “bad”. We the. Add back in single or groups of bacteria and enzymes that are safe and desirable for whatever food we are making. Then by adjusting the temperature, pH level, salt, moisture, and time we can control the growth and decline of the bacteria preventing undesirable or harmful bacteria from growth and promoting the bacteria we desire. I also want to point out that bacteria not found in the milk can be introduced into the food at almost any step (if not handled safely) and potentially cause issues with the end product. These issues usually are simply a change in flavor, texture, or, in some cases, harmful to one’s health."
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[
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|
lxegi6
|
What is the concept of months? Why Feb has only 28 while some have 31? When did the concept of 365 days' year come in people?
|
Other
|
explainlikeimfive
|
{
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"The short answer, Romans, the medium answer, Julius Caesar + the Egyptians. The more complete answer is that the Romans had the concept of months since their founding, following a lunar cycle with days added every time the year got too out of sync with the seasons. In the year 46 BCE, Julius Caesar decided that this system was dumb, and easy to manipulate (because he had been the one doing the manipulation for the last 20 years). So he recruited the help of some Egyptian astronomers to revamp the calendar. Egypt had a 365 day year, divided into 12, 30 day months, + 5 days at the end. (They actually had several different calendars, but this is complicated enough as it is) Julius coopted the Egyptian system, with a few modifications. First, he made February 28 days, and put those other days into 31 day months. This is because the Romans had a superstition that February was an unlucky month. Then, he took the +5 extra days, and also put them in as other 31 day months. Last change he made was to automatically add an extra day to February every 4 years to keep the alignment with the seasons.",
"A year's duration comes from the seasons, which can be tracked by looking at the stars. Seasons are super important for agriculture--you wouldn't want to plant a crop as winter is about to start--which is what spurred astronomers to develop a method for tracking the seasons accurately. Earth orbits once per 365.24... days, hence a 365 day year that adds an extra day roughly every 4 years. Months are prompted by a desire to have a smaller unit of time that's bigger than a day. The moon's cycle offers a convenient and easily tracked period of about 29.5 days, so it influenced that period. Unfortunately the moon's cycle is neither a whole number of days nor an even fraction of a year. To understand the modern calendar it's best to turn to Rome. The Roman calendar had, at one point, a mere 10 months. Roman culture preferred odd numbers to even ones, so these months had either 29 days (\"hollow\" months) or 31 (\"full\" months) (aside: I'm glossing over a *lot* of revisions of calendars here; some had 29 and 30 day months, some keyed directly off the moon, etc). These months were the equivalent to modern day March - December, which explains the names of Sept-December (sept, oct, nov, and dec are latin prefixes for 7, 8, 9, and 10, and these were the 7th through 10th months. Note that initially July and August were named similarly, as quintilis and sextilis, but they were later renamed after Juilus and Augustus. A popular myth is that July and August were inserted, but they were merely renamed). That calendar's start date made good sense from a seasonal perspective: it was keyed off of the spring equinox, towards the end of March. Note that the Romans counted dates in terms of the days until certain key dates of a month, as opposed to the modern system of counting up from the first. Even in modern times the spring equinox is in late March. However, it doesn't take much math to recognize that a year of 10 months, none with more than 31 days, is never going to get up to the 365.24 days needed for a full year. If you just had those ~300 days then the seasons would slip by a *lot* each year, to the point of making it useless for agriculture. To avoid this problem there was an additional unnamed \"intercalary\" month (literally \"between years\"), which was about 60 days long. It was up to certain government officials to determine when this month was over and it was time to declare the new year. Unfortunately, many political positions turned over with a new year, so that led to the duration of the intercalary month being unreasonably short when opponents were in power, or unreasonably long when allies were in power. That system was tossed in the trash and two new months were added. Not July and August, as many may claim, but January and February. In some calendars these were tacked on as the 11th and 12th months of the year, while in others they were the 1st and 2nd. Having February as the last month of the year explains why it gets \"whatever is left over to hit 365\" days, which turns out to be 28-29. However, it ultimately settled in as the 2nd month of the year over the course of many calendar reforms. Those calendar reforms ultimately moved away from Romans' 29 and 31 day months in favor of 30 and 31 day months, still with February as the month that gets what's left over. And that's how we wound up with a calendar that starts on an unremarkable day in the middle of winter, with months that schoolchildren have to learn a mnemonic to remember the duration of, and with the second month of the year being the oddball that has to pick up the slack to keep the year from drifting."
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lxf33x
|
Why is it that the brain can generate music with extremely high clarity but not as much with smells and tastes?
|
Biology
|
explainlikeimfive
|
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"The limbic system is responsible for converting short term memory into long term memory and takes up quite a large portion of the brain. Music comes from multiple sources, primarily hearing, but also sensation of waves shaking your body and sight. There are many avenues to receive that kind of information. In comparison, the sensation of smell comes solely from the olfactory bulb in your nasal conchae (way up your nose), and it is pretty small. Its kind of like this. Would you prefer to watch Star Wars on a big or little screen. You're always going to prefer the big screen and remember finer details far better than if you chose the smaller one.",
"Smell is actually the strongest sense linked to memories. But, as with everything, not everyone's brains were created equally. Others have mentioned that not everyone thinks 'audibly'. That being said, if you are doing or experiencing something you want to remember particularly well like hanging out with an aging relative, burn/spray/etc. a specific smell you'd like to associate with it.",
"I wouldn’t be surprised if it had something to do with your capacity to verbalize your experience with music. We are better trained to describe vocal intonations and words than describing smells and tastes. Professionals who invest a lot of time and effort into taste and smell (think chefs and perfumers) are able to very precisely recall details.",
"Smells and tastes are simple *things*, but music is a set of complex patterns. Our brains are designed to learn and memorize patterns because that ability is useful to survival. I'm a fan of classical music, and I always marvel how so many high level conductors have committed to memory incredibly dense and complex pieces of music. Here is a performance of the well-known [Beethoven's 9th Symphony,]( URL_0 ) conducted entirely from memory by [Daniel Barenboim.]( URL_1 )",
"MAIN IDEA: Throughout history, processing and more importantly REMEMBERING **VISUALS AND AUDIOS was much more important than remembering smells**. A lot of the human perception is visual (around 70-80%) and the next big chunk is hearing. When people were **hunters**, it was much more relevant to be able to **see** prey/visually identify a threat, respectively to **hear** prey/acoustically locate a threat. Plus, it was much more practical to be able to memorise these 2 parameters, as it was easier to educate others. ***(It's much easier to describe how a thing LOOKS and SOUNDS like than to describe how it smells like)***. Thus, the parts of the brain where **visuals and audios** are stored are much more developed and can reproduce stuff more clearly, and usually more quickly. It's a survival skill. \\^\\^ Plus, listening to something in your head brings joy while remembering a smell just makes you want it more. & #x200B; Hope this clears things out.",
"There's no one way people's brains conceptualise information like that, I for one can generate sounds and smells and tastes with equal clarity and quite strongly too, but I struggle with visual images in my head, it feels disconnected and foggy at best. Using an example of a fallen apple next to a tree, I can make out the outlines of objects, think of each component as a concept (the grass, the tree, the apple) or I can visualise things like individual textures, but not any of this combined. When it comes to audio I can hear it as clear as if I just played it back, with whole songs playing through if I want to. I can replicate tastes and textures of specific dishes I had over a decade ago, like how a specific curry tasted and felt like when I was visiting Indonesia in 2008, as if I was eating it right now. Edit: got age and year mixed up in my head"
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|
[
"url"
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[
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|
lxf7v1
|
In a world full of VPNs, how do governments and corporations point a finger at a certain country for hacking their infrastructure?
|
Technology
|
explainlikeimfive
|
{
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"text": [
"Some methods of identifying the origin of the attackers could include looking at the code of the malware; what languages are used? Although this has been used by attackers in the past to pose as another nation (the creator of the Mirai botnet wrote \"i love chicken nuggets\" in russian as a comment in the code, and the americans were looking at russian sources for a few months. the creator was american). Other methods include looking at the TTPs (tactics, techniques, and procedures) used during an attack. For example, if a certain APT (advanced persistent threat) group was observed using a specific technique in terms of reconnaissance, followed by another specific technique to gain initial access, then we can build activity patterns. If we see similar activity being conducted towards similar targets (let's say, all the targets are in the finance industry within the same country) then it is widely believed that it is safe to assume this was the same group. Personally I don't much agree with this last one, as it is easy to copy techniques and attack vectors. I asked this exact same question to a superior of mine in the cyber industry who has worked for NSA and he told me that in most cases, secret government agencies have wiretaps, moles, and compromised / insider sources that give them reliable info on who the source of the attacks is. This is why you'll never see a detailed article explaining how they know that a certain country has allegedly attacked another. My follow up question was \"then how do we, as civilians, know for a fact that this country really has attacked this other country, without just blindly accepting what we are told?\". His answer, \"you don't\".",
"> In a world full of VPNs, how do governments and corporations point a finger at a certain country for hacking their infrastructure? Something as trivial as an IP log of recent connections isn't really a relevant factor in these situations. Some concerted efforts of targeted digital vandalism are so demanding and complex, so expensive and resource-extensive, that the only conclusion left to make for any security auditor is that the attack was conducted by another *nation*, as only another nation could have had the means to do it. The rest is following up on individual leads, money trails and narrowing down motivations and capabilities - regular (albeit high-level) intelligence work. Actually publicly pointing a finger is a whole separate diplomatic decision though and can, of course, be done either with or without any evidence."
],
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16,
14
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|
[
"url"
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[
"url"
] |
|
lxfg7r
|
Is 'Calorie in, Calorie out' accurate description of human digestion? I'm thinking that food passes through the body at a relatively steady pace, so if there is more food then all the food has less time to process, right?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpmrwjl",
"gpmtmde"
],
"text": [
"Like many things in human biology Calorie in: Calorie Out is a big over simplification. Technically you can accurately measure the calories in any food item. You take it and burn it in a device called a calorimeter. But human bodies are more complex and messy. The problem is we all metabolize food at different rates. Food actually doesn't move through us at a steady pace. It varies from person to person, and even day to day for the same person. Fiber and fat content can make a difference. Then the calorie out math is even fuzzier. It takes more calories for a 300lb person to walk a mile than a 160lb person. So if you're walking on a treadmill and it's giving you a calorie count, that's a rough often optimistic guess. Some people burn more calories at rest than others. Your metabolism can do wacky things to conserve energy to keep you from loosing weight. At the end of the day loosing or gaining weight comes down to calories in vs calories out. But what a calorie is in the lab vs the real world is more complicated.",
"Food doesn't pass through the body at a steady pace at all. Sugars are very easy to digest for example. If you eat candy, chocolate, or similarly sugary foods, the sugars are almost immediately absorbed directly through the stomach lining. A food item with more fibre like legumes will take your body far more work to digest and as a result, these foods release their energy slowly over time. That's also why eating a candy bar will give you a huge energy boost almost immediately. Quickly followed by a crash as all that sugar is made available and used up at once. It's not satisfying as you become hungry again shortly afterwards and it's not great for your energy levels because they quickly spike and plummet again. Those legumes on the other hand keep you satisfied for much longer as your body works on them and gradually extracts energy from them over a longer period of time. This is also why you get fat much more quickly on sugary and fatty foods. They're high energy, digest quickly and do very little for keeping your hunger at bay. So it's very easy to overeat on them. By comparison, those vegetables are low calory and keep you sated for much longer while still providing you with energy long after that candy bar stops doing so."
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6,
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[
"url"
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[
"url"
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|
lxi0at
|
How can themeparks snap a crystal clear picture of you on a rollercoaster going 70mph
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gpn3gfj",
"gpnbdnv",
"gpnhi1n",
"gpn4n1z",
"gpnb9zo"
],
"text": [
"Motion blur occurs when the camera takes too long to generate the image. By the time the last bit of information is taken, the image has changed noticeably. So if all the information is taken in a very short moment, that difference is very small and the image looks sharp. However since the camera has less time to collect the light for the picture, shorter exposure times need a brighter scene. So the flash needs to be stronger or the scene just needs to be very well illuminated.",
"To further the other comments - if the location where they choose to take the photo is lit primarily by the flash (and I've not seen a roller coaster photo where that is not the case) then the duration of the flash effectively becomes the shutter speed (because the image is lit by the flash - and the camera can only capture an image while the flash is \"on\"). Flashes can have *extremely* short durations (1/1000 down to 1/20000 of a second) this means that they are really good at stopping motion.",
"Three things: 1. They use fast shutter speeds. That means that the shutter is only open for a very short period of time to gather data. And during that short period of time, you don't move much. Imagine you took a video at 3200 frames per second, then advanced it frame by frame. The movement would be almost imperceptible. That is how much you move while the shutter is open. They probably shoot at 1/3200th or even 1/6400th. The down side to having the shutter open for such a short period is that there is not much light that gets through in such a short period of time, so... 2. They use bright, fast flashes. That flash will pulse with each shutter click and it will be timed to illuminate the riders for the same length of time. So the riders are getting hit with a very bright light for only 1/3200th of a second and anything that happens outside of that window is too dark to really process. 3. They use angles to their advantage. Look out the side window of your car on the highway and things will be zooming by and you can't really focus on them. But look out the windshield and you can easily focus on approaching items. Cameras have a depth of focus. These particular cameras are set to focus on a point in space that is let's say...3 feet deep. So as the riders are approaching the camera from the background toward the foreground, they will remain in focus for 3 feet as they pass through the camera's view. In 1/3200th of a second, they will probably move less than a quarter of an inch. So there is plenty of time to capture them in focus. But if that camera were placed perpendicular to the coaster train and shooting from the side, the riders would zoom through the view much faster. It's the difference of trying to catch a baseball thrown toward your face and trying to catch a baseball thrown *past* your face from the side. It's much easier to see it coming straight on.",
"A blurry pictures is normally due to one of two things: 1. Unfocused lens 2. Moving subject In normal cases a camera needs to find the subject, focus on it and take a picture before these settings need to be changed to keep a clear picture. In a rollercoaster camera you place the camera in a set place and calculate the focus of the lens and the position of the subject before the picture is taken. When the train reaches a camera trigger the camera takes a picture of this already decided place. Anything there will be sharp. The trigger sensor helps the camera to know when the subject is at the “right” spot. This in combination with a decent flash is what results in a clear picture.",
"They can use a fast shutter speed because they have the flash lights. If the lights didnt flash when you went past there wouldn't be enough light hitting the lense in the time you were there, so the image would be dark. If the shutter speed is lower you get motion blur."
],
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44,
23,
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3
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|
[
"url"
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[
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|
lxidy2
|
why can DNA transcription and translation processes be 'wrong' and make mistakes?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpn7vj4"
],
"text": [
"DNA/RNA are built out of smaller units called nucleotides, which are a bit like the links in a chain - a strand of DNA/RNA is made up of many individual nucleotides stuck together. To produce a new strand, you need to get a bunch of nucleotides and put them in the right order, so your main job as a protein designed to do this is to figure out what the right order is. There are four DNA nucleotides - T, A, C and G. There's also a fifth nucleotide, U, which is the RNA version of T for an interesting but irrelevant reason. These nucleotides are the links you see in graphics of a DNA helix, like [this one]( URL_0 ). Notice how each of these links is split in the middle into two different colours. These are a visual representation of the DNA structure. See, DNA has two different strands each with its own nucleotides, that stick together a bit like a zip - the nucleotides on one strand of the DNA stick to the nucleotides on the other strand to form this stable helix structure. The fact they stick together like this is how proteins know what the right order of nucleotides is when replicating the DNA. Nucleotides exist in matching pairs that preferentially stick together. T and A are a pair, and C and G are a pair. To produce more DNA/RNA, proteins unzip the DNA to expose the nucleotides on one of the strands, and then free floating nucleotides come into the protein complex and if they stick to the next exposed nucleotide in the line, the protein glues them onto the end of the emerging strand. So if the exposed DNA strand says TTCAGACGA, then the proteins will produce an RNA strand of AAGUCUGCU, because those are the RNA nucleotides that stick to the DNA strand (noting that U here is substituting in for T). However, this stickiness is not particularly strong. It's done using interactions called hydrogen bonds, and the number of these bonds formed between a pair determines its stickiness. T and A pairs form 2 hydrogen bonds, while C and G pairs form 3. These have positive and negative ends, a bit like magnets, so TG and AC pairings aren't going to happen, but you can get TC and AG pairings, they'll just be uncomfortable and not fit properly. There are other proteins that check for these uncomfortable pairings and replace them with the right nucleotide, but they're not super reliable and there's a good chance they replace the wrong one and cause a mutation. Transcription errors occur then when the wrong nucleotides stick together. This isn't a big deal for RNA cos RNA lasts for such a short time, but the fixing proteins can permanently establish these mistakes as mutations in DNA, occasionally. Translation errors follow a similar process, but due to a mis-stickying between the nucleotides of the mRNA and the nucleotides of the already built tRNA molecules."
],
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7
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"https://external-content.duckduckgo.com/iu/?u=https%3A%2F%2Fd2noibkeom3qqq.cloudfront.net%2Fwp-content%2Fuploads%2F2017%2F02%2FDNA-helix-molecule-genetic.jpg&f=1&nofb=1"
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|
[
"url"
] |
[
"url"
] |
|
lxivrc
|
When eating hot food, why do we feel the heat/warmth until our stomach? Does our digestive system have nerves that respond to heat?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpnapcs"
],
"text": [
"yes, our digestive system contains nerve endings that respond to heat, as well as a lot of nerve endings that respond to a lot of different conditions. Nerve endings in your stomach are constantly monitoring pH for example."
],
"score": [
6
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
lxjwb8
|
what does Spring Boot do?
|
Reading about the framework Spring and having trouble understanding what Spring Boot and Spring Batch does if someone has a simple analogy and what was the old way of doing things and what Spring solves?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gpndpr5",
"gpnem7y"
],
"text": [
"I don't have extensive experience in it so I'm sure others can explain some of the finer points, but one of the major things it does is it's a standalone web application. You don't need to configure a web server, or manage server settings, or anything like that...you build your application, and double-click the executable and your web application runs all on its own. Old Method: Choose and download/install web server software - > Configure web server - > Build and Deploy web application to server Spring Boot: Build and deploy web application",
"Spring allowed you to wire together bits of an application to make it do whatever you want, but didn't do it for you. So you had to have lots of configuration files telling it how one thing relates to the other. For example, you would need to say that this class need to be initialized before this one, and to get some data from this other file to set a field in that class, etc. Spring boot has some of the wiring built in so it is easier to get things up and running with less need to \"boilerplate\" configuration, especially if you use starter templates for specific types of applications like web apps. The trade off is you need to follow it's conventions and it is a bit if a \"black box\" with lots of stuff happening behind the scenes. Spring boot starter templates also give you built in commands to test, deploy, and run applications so you don't need to write them yourself, which is a huge time saver."
],
"score": [
3,
3
],
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|
[
"url"
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[
"url"
] |
lxkxcd
|
How does rock melt?
|
I feel like I’m missing a part of basic chemistry understanding. What happens to rock on a molecular level when it melts? Does its composition change? Do all things melt under the right conditions?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gpnieqb",
"gpni40e"
],
"text": [
"Rock melts the same way ice does. The molecules in the rock jiggle around more and more as they heat up, until eventually the attachments between them can't hold them in place and they begin to slide around one another. The only difference is that because rocks are usually not a single chemical (\"mineral\" is the term for those that are), they often have a partial-melt phase where some (but not all) of the minerals in the rock are melted. To see this in reverse in your kitchen, melt some butter and mix it with hot water, then let it cool: you'll see the butter freeze out before the water does, producing globules of butter floating in liquid water. In rock you might have, say, crystals of [fosterite]( URL_0 ) floating in a melted lava of [silica]( URL_2 ) (I am picking two minerals at random, I don't know if these commonly occur together in practice). This process, which can separate minerals of different melting points, is called [fractional crystallization]( URL_1 ) and is important to understanding how minerals are deposited by volcanoes. [EDIT: Actually, butter itself is an example, which is why melting a stick of butter in the microwave can produce a partial melt of some solid fats in melted oil.] > Does its composition change? Usually not on a molecule-by-molecule level, but as a bulk rock it can (because of the fractional crystallization just mentioned). If one mineral with a high melting point cools and hardens and deposits earlier on in the flow of melted rock, it can reduce the concentration of that mineral later in the flow (and thus increase the concentrations of things with lower melting points). Imagine pouring your water/butter hot liquid down a very cold slope. The butter would freeze out immediately and you'd get solid butter near the top of the slope, while the water would flow further and you'd get mostly butter-free ice at the bottom. > Do all things melt under the right conditions? Yes - or they do unless they break down into some other chemical below their melting point (as e.g. wood does).",
"Yes, (almost) all things melt under the right conditions. When melting, the rock loses its crystalline structure and becomes a liquid. The atoms constituting the rock rearrange themselves as kinda free-moving molecules."
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14,
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"https://en.wikipedia.org/wiki/Forsterite",
"https://en.wikipedia.org/wiki/Fractional_crystallization_(geology\\)",
"https://en.wikipedia.org/wiki/Silicon_dioxide"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
lxl5kc
|
Why do computers slow down, but then you restart them and they work again?
|
Could you explain in the form of an analogy? Also, has this improved over time? Does it have anything to do with registry and defrag? Is it different for Mac vs PC? Thank you :)
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gpnldiv",
"gpnk07r",
"gpoa3rw"
],
"text": [
"* Think about a computer like this: * You are sitting at a large desk next to a huge set of bookshelves. * You are the CPU * The table is the system memory (RAM) * The bookshelves are the system storage (Hard Drive, SSD, external drives etc) * In order to do something, you need to take the related stuff off the shelf and put it on the table. * Now think about what this table will look like as you start to do your tasks. * Computers appear to do many things all at the same time. * The truth is they only do one thing at a time but very very quickly switch between tasks. * So the table gets filled with things you're working on very quickly. * Switching between these things starts to get time consuming. * Restarting the computer is the same as putting everything back on the shelf and totally clearing off the table. * Those first few tasks you do will be quick because you aren't searching through a table full of stuff to get what you need.",
"There are several reasons, but one of the most-common reasons is that everything you do on your computer takes up some of the limited memory in the computer (specifically the RAM, or Random Access Memory, which is different than space on a disk). As you do things on the computer, such as browse Reddit, your computer keeps taking up more memory with every post you click, every photo you view, every link you click. When that memory becomes more limited, your computer operates more slowly, as it struggles to try to \"find a place to fit more stuff.\" However, once you restart your computer, most of that memory is wiped clean and you start fresh, so your computer is often faster. Basically, on a restart, your computer \"empties the trash can,\" so you can start filling it up again, without constantly having to try to compact the trash to fit more in the can.",
"Follow up to your question about defrag: You'll recall the analogy about hard drives being a file cabinet. While it does store the data, it's not really in the shape of a file cabinet. Instead imagine a grid; letters going across and numbers going up and down. When it needs to store some information it'll take, for example, 5 blocks of space. So it'll just choose A1 - A5 and put them there. But what if one of those blocks is occupied? Now being human your first instinct would probably be move that occupied one somewhere else and then lay the 5 blocks from the same program all next to each other. The computer doesn't do that however. The computer uses a firm \"Any available surface\" method of filing. So if block A4 is already occupied, it'll choose A1-A3 & A5-A6 to store the information. But it does this for everything stored on the hard drive. So a visual representation of the hard drive would be less like a filing cabinet, and more like the warehouse from raiders of the lost arc; along with needing a treasure map to find the relevant information when it tries to pull it. [ URL_0 ]( URL_0 ) Any time it needs to put down something new it will find anywhere it can cram a part of it and make a note of \"I left pieces here, here, here, here and here' for when it needs to grab them again. That's where hard drive speed comes in for computer speed, how fast it can go sorting through all those boxes and pulling the relevant info. Defragmenting the hard drive is when the computer will actually go through and rearrange these boxes into a fashion that makes more sense; grouping bits of data together in actual patterns rather than at random; so when it needs to find something it's less like following a treasure map and takes less time. PSA: Solid State Hard drives (SSD) you do not want to defrag. While they are the raiders style of organization, it's actually carefully controlled so that it distributes wear and tear evenly on the hard drive; improving it's lifespan. A normal hard drive once a 'shelf' breaks it's corrupted, and can cause more and more problems as it tries to work around that. SSD's will calculate and arrange things on the fly so prevent any of those shelves holding boxes from getting an unusual amount of wear and tear; meaning they will last longer without breaking. Defragmenting and manually rearranging the load will mess with it's carefully designed system and put additional strain on portions of the drive, shortening it's lifespan and eventually leading to damage and failure. A SSD can last much much longer than a spinning drive hard drive because it's storage method intentionally sets up to keep it going a longer and messing with that can shorten it's lifespan."
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5,
3
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|
[
"url"
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[
"url"
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lxlr3w
|
Why do we only start liking certain foods when we get a lot older?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpnyksn"
],
"text": [
"Children tend to have much stronger senses of taste than adults. Your sense of taste does wear out over time and because of that, things that tasted absolutely horrendous as a kid is more palatable as an adult. Because of this, kids tend to prefer simpler flavours for their food."
],
"score": [
3
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|
[
"url"
] |
[
"url"
] |
|
lxludo
|
Why do planets in our solar system orbit the sun on the same plane?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gpnn7x8",
"gpno2hf",
"gpo3gbh",
"gpnngdb"
],
"text": [
"Conservation of angular momentum. Basically, things that are spinning in a direction will keep on doing so. The solar system started off as a big cloud of gas and dust that was spinning in all sorts of different directions. However, as things spinning in different directions collided their angular momentum would, to some extent, cancel each other out. If you imagine \"adding up\" all this momentum in different directions, a bunch would cancel out and the rest would combine to form momentum in a single direction. Over many millions of years, as stuff continued colliding, this process continued until there was, for the most part, only objects spinning in one direction in a single plane. There are plenty of objects in the solar system that didn't collide with enough stuff for this to happen, but they're mostly very small and very distant from most other things in the solar system.",
"They are not orbiting in the same perfect plane but it is pretty close. This comes from the time before the planets had formed when the solar system was just a cloud of gas and dust. The particles were just orbiting what would become the Sun in any random orbit they happened to have. The problem with this is that the particles often crashed into each other. If not actually touching they would often get close enough to get a gravity sling from each other and pull each other into different orbits. Quite often these orbits would take them out of the solar system entirely or on a collision course with the Sun. But some of the particles were less likely to crash into each other then others. The particles that were orbiting in the same plane as most of the other particles, just by random chance, would have fewer collisions. So as as particles collided with each other over and over again more and more particles would be these that orbited in the same plane. And eventually you got to the current state.",
"The ones that orbited on a different plane collided with each other, or gravitationally slowed each other down, and their movements cancelled out. After a long time, they're all going on the same plane where they can't run into each other.",
"They all formed from a relatively flat disc that was orbiting the sun in that plane. This is also why they all orbit the sun in the same direction and why most of them also rotate on their axes in the same direction as they orbit the sun (Venus, which rotates backwards, and Uranus, which is on its side, are the exceptions, both believed to have been caused by giant impacts in their early history \"knocking them over\")."
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6,
4,
4
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|
[
"url"
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[
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|
lxm1yp
|
Why is Tom Cruise typically used as the deep fake model?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gpno34p",
"gpnpq2t",
"gpnonj0"
],
"text": [
"Because Tom Cruise is both instantly recognizable and *just* ~~crazy~~ unpredictable enough that you’ll likely believe the deep fake for at least a moment.",
"Deepfake and other image stitching technologies like it require a good amount of source data such as pictures of someone taken from all angles, all facial expressions, as many lighting schemes as possible. What your saying ok a deepfake is a reconstruction of Tom Cruise's face onto someone else's face. More source pictures/video to draw expressions from means a better and more believable reconstruction.",
"There are an absurd amount of photos taken of Tom Cruise through the years. And he still looks the same now as he did as a teen. When you are doing articifial intelligence and patern recognizion software you want as much data as possible to get a good result. And you would be hard pressed to find a celebraty there are more portraits of then Tom Cruise."
],
"score": [
12,
7,
6
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"text_urls": [
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|
[
"url"
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[
"url"
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|
lxm7t7
|
Why do plants absorb nitrogen from the ground and not the air?
|
Why would the plant need nitrogen from the ground when the air is 78% nitrogen?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpnp6zd",
"gpnpib6",
"gpnpjlr",
"gpnpxpc"
],
"text": [
"Because the nitrogen in the air, N2, is very, very hard to actually make use of. It's phenomenally stable. There are some bacteria in the ground that are able to do it. They can turn atmospheric Nitrogen into ammonia (NH3) or similar compounds. Plants are much more readily able to make use of compounds like these to, say, construct proteins.",
"The nitrogen in the air is bound up in bonds between two nitrogen atoms. Those bonds are *extremely* strong - in fact, they're just about the strongest bond in any molecule. Breaking that bond is very difficult as a result, and most living things can't do it, which means they can't put that nitrogen into the molecules necessary for life. The technical term for \"converting N2 from the air into useful atoms of nitrogen\" is [nitrogen fixation]( URL_0 ). In the natural world, it's done mostly by specific species of bacteria. Figuring out how to do it artificially took a very long time, and led to the development of modern fertilizer (without which we couldn't produce anywhere *close* to the same level of farm yields that we do today; nitrogen is often the bottleneck for plant growth). ---- As a side note, the reverse process - nitrogen in other compounds turning into nitrogen gas - releases a ton of energy, which is why many high explosives contain nitrogen. In particular, it's why fertilizers are often explosive in large amounts (like the Beirut explosion last year).",
"The nitrogen is *there* but the plants can’t get it. The nitrogen needs to be taken from a gas and bound into organic compounds like ammonia, something plants rely on diazotrophs to do, bacteria and archaea that can “fix” nitrogen into such compounds. Organisms evolved in ecosystems so while it might be convenient if they could fix nitrogen themselves it just didn’t turn out that way.",
"There actually are some plants that can absorb nitrogen from the air. Legumes for example do this, and it's a process called nitrogen-fixing. However, plants didn't evolve the ability to do it themselves. Instead, they evolved to form symbiotic relationships with nitrogen-fixing bacteria, that they incorporate into their own structure similar to the gut bacteria in humans. It's much easier for plants to evolve this symbiotic relationship than to directly evolve nitrogen fixation mechanisms, so this is the thing that evolves."
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|
[
"url"
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[
"url"
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lxmurq
|
Why does it feel like your finger is vibrating when gliding it across some phone edges or some surfaces?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gpnvytn"
],
"text": [
"It's the repeated transition between kinetic and static friction forces, which aren't equal. You're applying more pressure into the glass than along its surface. So what happens is the lateral pressure to slide your finger builds up until it overcomes the static friction and your finger starts to slip, but very quickly your finger tip tissue is \"reset\" and the pressure angle relaxes because the finger tip is sliding smoothly away from the previous spot. Because you're exerting heavy downward pressure at some point friction overcomes the slide and your finger stops. It stays there until your hand catches up to the finger tip location and the lateral pressure again builds as the pressure angle adjusts and overcomes the static friction and it starts to slide again. This occurs generally on surfaces where your skin generates fairly decent static friction to grip something, but the kinetic friction is quite a bit lower once it starts sliding. Because those two frictional forces are so different, it creates that chattering or buzzing sensation when the swap between stationary static friction and sliding kinetic friction occurs rapidly."
],
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[
"url"
] |
[
"url"
] |
|
lxn0o2
|
why do our muscles shake when electricity touches us but not when light touches us. If it isnt energy that makes our muscles shake what is it?
|
Physics
|
explainlikeimfive
|
{
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"First of all, the light does not reach your muscles, it just reaches your skin. So it cannot have any direct effect on the muscles anyway. But more importantly, muscles cannot just convert any sort of energy into movement, just like a diesel engine can only use diesel and not steam or wind or electricity. The energy source for muscles is a specific chemical \"fuel\" in your body called ATP, muscles can only use that and nothing else. However, while the ATP is the energy source, your brain has to control the muscles somehow, and it does that - simplifying here - by sending electric impulses along your nerves. If you touch an electric cable, the electricity will cause havoc with this communications system - your muscles believe that they're given random, frantic orders, and act accordingly. So, in short - muscle spasm don't happen because of too much energy, but because they recieve random orders.",
"Our nervous system works on electricity too. When we want to raise an arm, for example, an electrical signal goes through our nerves and makes the required muscles contract when it reaches them. So when some external electrical current touches our muscles, it’s no different to them than the normal nerve signal.",
"Animal cells don't have any machinery that can convert light to any usable form, unlike \"electricity\" (in the form of action potentials). It's like asking why solar panels don't generate an electric current when you shake them. Mechanical energy and electromagnetic radiation might both be forms of energy, but solar panels are only built to be able to convert one of them to electricity.",
"I think there's something fundamental here that needs to be cleared up first. When you get electrocuted, the electric current isn't *powering* your muscle cells. It's interfering with (overwriting, in a way) the electrical signals that are normally transmitted between the brain and your muscles. Whether you're getting electrocuted or not, muscles are only ever powered by chemicals stored in the cell (adenosine triposphate, ATP). Neither light nor electricity can provide energy to a cell."
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[
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[
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|
lxnsx5
|
Why does being drunk save u from otherwise "Fatal" accidents?
|
title pretty much says it all, i heard stories (Dont know if true or not tbh) of people falling from great hights and people being ran over by trains ect. surviving, mainly (or really?) because they was drunk
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpny7y2",
"gpnygi6",
"gpny8ud"
],
"text": [
"Your reaction times are way slower when you're drunk so you don't instinctively tense up before impact like a sober person would. Being loose on impact makes it harder to break things.",
"Part of what can hurt you in a fall is your instinct to tense up. This increases your body's stiffness, which tends to concentrate loads around the impact point and break things. If you are relaxed and \"floppy\" you can spread the impact load out more and potentially lessen the overall damage. If you're drunk you're more likely to pass out or be sufficiently unaware and be more relaxed. BUT...there's a tight window where that's going to help you...fall from high enough, and you'll die regardless. Hit in the wrong orientation and you're going to die regardless. And the risk of falling in the first place goes \\*way\\* up if you're drunk (poor judgement, poor balance, poor coordination) so you're certainly not safer by being drunk.",
"Free m what I have heard it usually makes it so your body stays limp and doesn't tence up for impact making it made likely you will survive. not sure how true it is and it can be only once factor of many."
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|
[
"url"
] |
[
"url"
] |
lxnwc2
|
Why can't we concentrate nonstop? Why do we need breaks?
|
EDIT: I mean productive work such as learning.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpnz4mn"
],
"text": [
"You'd be amazed how long people can concentrate when the environment is designed to be stimulating. People can play video games, stare at a phone, watch TV, or look at slot machines for periods of time that are basically just constrained by sleep, assuming they are extremely stimulated by them. The problem is that extremely stimulating tasks are generally not very productive, they're usually entertainment."
],
"score": [
20
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"text_urls": [
[]
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|
[
"url"
] |
[
"url"
] |
lxowgz
|
Why are some pregnancy cravings so strange?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpo4y6m"
],
"text": [
"Building up the fetus and placenta requires a whole different set of nutritional requirements. The body passively catalogs all the nutrients from your diet. If your body lacks say a certain vitamin and the thing you eat containing high amounts of that vitamin is say, pickles, you will crave pickles. If you eat a wide range of foods, it's easier for your body to crave foods that easily sastify your nutritional needs. If your diet is limited or nutritionally poor, you get cravings for the limited selection your body knows about which may also be high in fats and sugars (fast food)."
],
"score": [
9
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
lxp513
|
Why are peoples' own noises and smells usually dialed down, such as not being affected by their own snoring and not noticing their body odor?
|
Why does the brain seems to dial down things that we produce; even the obnoxious snoring or noises made while sleeping don't affect us? Similarly, people don't usually get annoyed by their own talking or yelling to themselves.
|
Other
|
explainlikeimfive
|
{
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"text": [
"You have to live with yourself all the time. If you were constantly focusing on how you smelled, talked, acted, etc, etc, you would quickly find your own existence barely tolerable. You get used to the sounds and smells you make and your brain starts filtering them out, because paying attention to your surroundings is more important for survival.",
"The most basic signs of \"intelligence\" is the ability to respond to your environment. You poke the thing, it reacts The next step on the intelligence ladder is ignoring stimuli. You poke the thing often enough, it will stop reacting when you poke it. Your brain is constantly fed an amazing amount of information, so to save on processing power it chooses to ignore certain things. You can hear your own heart beat/ feel yourself breathing/ feel your clothes/ smell yourself. But, because these things are always there, your mind chooses to ignore it in favor of processing other stuff. So, why can't people smell themselves? They can, their brain just chooses to ignore it.",
"You don't sense *things*, you sense *changes* in things. When you get constant input, your senses stop responding to it. That's why jumping into a pool feels cold, then an hour later you don't even notice the water temperature at all.",
"Novelty makes us pay attention to things. After a while we block it out. Think of your house smell vs smelling someone else’s house. The same with sound, people that have lived all their lives in noisy places tend not to pay attention to them."
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|
[
"url"
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[
"url"
] |
lxq171
|
Why are SSDs reliable for long-term storage, but USBs fail within a few years?
|
Since both SSDs and USBs use flash storage. I tried searching online and found [this thread]( URL_0 ) and [this video]( URL_1 ), which were somewhat helpful but not entirely. Does anyone have a great analogy or digestible summary?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gpod06k"
],
"text": [
"Different levels of reliability in the controllers and how they're built. The basic storage technology is the same but SSDs use a much more robust construction that can withstand more read/write cycles before they accumulate too much damage to function, more sophisticated controllers to spread the damage around, and redundant sections to take over if one section fails. Think of it like tires on your car. USBs are cheap tires...eventually one of them is going to wear out and pop. SSDs are expensive long life tires, and you do rotation, alignment, and balancing all the time to make sure they're in good condition, and you have a full size spare."
],
"score": [
4
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|
[
"url"
] |
[
"url"
] |
lxq9la
|
Why does the rotation of a wheel on a car force the car to move? I was told it was due to the wheel 'pushing the ground and propelling the car,' but this seems a little basic.
|
I know it seems stupid but I can't grasp the Physics behind it. Thanks.
|
Physics
|
explainlikeimfive
|
{
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"text": [
"It helps not to think of it as rotation, just look at the patch where the tire touches the pavement. The engine is twisting the wheel, trying to push the tire contact point backwards. But it can't slide (because the tire is grippy) and the ground can't go backwards (because it's ground) so the only way for the bottom of the tire to move backwards is for the axle to move forwards. The friction between the tire and the ground is transmitted through the tire and wheel and shows up as a force pushing forward on the axle through the wheel bearings. As the car (and axle) moves forward, that little patch of tire on the ground lifts away...but it's a wheel, so as it rotates a new patch is coming into contact. Rotating the wheel makes sure that you've always got a piece of tire touching the ground to push off with. If the tire \\*isn't\\* grippy enough, the tire will slide over the ground, you spin your wheels, and don't go anywhere. If the ground isn't solid, the ground will go backwards and spray dirt/gravel behind you, and you won't go anywhere. Edit:typo",
"Because of friction mostly. Not sure where you're confusion is but you might just be over thinking it.",
"When a wheel rolls it's center moves around. Your car is connected to the center of the wheel by axels, so the center of the wheel's movement moves along with the center of the wheel. That leaves only two options, the wheel slips in place or the axel and car move. Wheels are pretty hard to slip, because cars are heavy, and tires have a lot of friction (high coefficient of friction).",
"That's it basically. Indeed, if there was no friction between the wheel and the road, the wheel would just spin. The friction creates a force from the wheel to the ground, and in reaction the opposite form from the ground to the wheel, and this force, which applies to the car, results in the car going forward. Energy dissipation caused by the friction would result in the car stopping quickly, but as the engine keeps providing energy and causing the wheels to rotate, the movement keeps going."
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|
[
"url"
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[
"url"
] |
lxrexs
|
If cold air sinks, why are high places like mountains so cold?
|
Earth Science
|
explainlikeimfive
|
{
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"gpoikfh"
],
"text": [
"Cold air sinks and hot air rises, yes. However, as you go up in the atmosphere to upper elevations the air also gets thinner. Thinner air means less to contain heat. That makes it get very cold, also the reason why people have to often wear oxygen in super high altitudes. Think of it this way. It's very cold outside, so you put on a very heavy jacket, and go outside. You feel comfortable, because your jacket is keeping you nice and warm. Now go back inside, and take off all your clothes except a t-shirt and shorts, and go back outside when the temperature reaches 40. You are cold right? but it's warmer. But you are cold because the level of insulation between you and the 40 degree weather is less and therefore you feel cold. Same basic concept. In upper atmosphere there is just a lot less air. So it can't keep the warmth."
],
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3
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|
[
"url"
] |
[
"url"
] |
|
lxs3su
|
what makes the snapping sound when we snap our fingers
|
Biology
|
explainlikeimfive
|
{
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"gponypz"
],
"text": [
"Your finger tip slapping against the palm of your hand. The snap doesn't come from the fingers releasing. It comes from the finger slapping to a stop when it hits your palm (and/or the adjacent fingers, depending on how you snap)."
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"score": [
11
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|
[
"url"
] |
[
"url"
] |
|
lxt9px
|
How do animals like fish or squids become completely see through including their organs and blood.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gppf1n1"
],
"text": [
"They're already about 90 percent water so all the tissues and organs are made super thin so light passes through. Notice that larger animals don't do this, besides structural issues, there's just too much stuff to be transparent."
],
"score": [
6
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|
[
"url"
] |
[
"url"
] |
|
lxtecq
|
When you burn fat on your body by exercise etc., does your body burn newer fat, or any fat?
|
If you only burn newer fat, does that mean that there is some really old fat in your body?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpouupf"
],
"text": [
"Your body has a fixed number of fat cells that store liquid fat inside of them. When you burn fat what's happening is your fat cells are being told to release energy in to your bloodstream. So it's sort of like if you had a bucket of water that you sometimes add water to and sometimes take water out of. Technically some of the water molecules may have been in there a long time just like how some of the fat molecules may also have been, but there would be no way to know exactly."
],
"score": [
29
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|
[
"url"
] |
[
"url"
] |
lxton5
|
why do people need to be taught about sex?
|
Why is it that humans need to be told about sex but it seems every other species that uses sexual reproduction knows it instinctively? am i just a fucking idiot? edit: once again i have proven myself to be an absolute imbecile.
|
Biology
|
explainlikeimfive
|
{
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"text": [
"It would come naturally if we didn't have sex ed too. It did before. Sex ed is supposed to be (but isn't because it's often garbage) more about safety, pregnancy prevention and making sure they have the proper information instead of school hallway misinformation about something with such consequences.",
"Humans don't need to be told about sex. Humans need to be told about *safe* sex, about how getting pregnant happens, about STIs, about social norms, etc.",
"Humans don't *need* to be taught about sex. Put ten babies in a room and give them no outside human interaction, and once they reach puberty they'll start figuring out sex pretty fast, because we have an instinctive drive to do it. In the animal kingdom (and humans before modern times), young creatures also have the advantage of seeing other members of their species doing it - nowadays, we tend to value privacy and don't do that as openly in front of our kids, thankfully. The reason we teach kids about sex isn't about the actual mechanism of it, it's more about all of the stuff that surrounds sex. Things like consent, safety, sexually transmitted diseases, pregnancy, all of those complex feelings that surround sex in a social context. That's not stuff that's instinctive, that's stuff that humans have figured out to keep ourselves and others safer and happier. That's what sex education is meant to be about, not just \"put A in B, repeat.\"",
"They don't need to be taught about it in order to do it. It's instinctual. What we teach people about is how human reproduction works in a physiological sense, how people get pregnant so you can avoid it if you want, how diseases are spread and how to avoid them, etc."
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|
[
"url"
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[
"url"
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lxvka1
|
why do DJs sometimes hold one of their earcups?
|
Other
|
explainlikeimfive
|
{
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"text": [
"Headphones off, they're listening to current music. Headphones on, listening to what to play next. One earphone up, matching beat and tempo/speed of both songs to mix well. Once upon a time I was a (very) small time aspiring DJ",
"Djs need to hear both what you hear, and the music they are preparing on you headphones. They can do this electronically, but many quickly put down an earcup for convenience.",
"So in order to prepare the next song, the DJ need to set the transition. That’s what he is doing most of the time, listening to the next version to the mix in advance in order to launch it at the right time.",
"Everyone answered your question already but they used to sell only one side. URL_0 It is kind of a pain to put the headphones on and off and then have to adjust one side of the headphones, so they came up with these one speaker hand held headphones. The people that I saw use these were guys that had residencies at clubs, so they had all the sound dialed in, and they would play for 3 or 4 hours a night. When I was a dj, it was very hard to hear your headphones when playing on a loud system (club system). So I would wear both sides on my ears and maybe just take one side off just a tad so i can still hear the club speakers. but to reiterate what everyone is saying, you are basically listening to two songs at once.",
"To make sure the beat of the next song matches the beat of the currently playing song. One ear to hear what is currently playing and the other to hear the one that will be played next"
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|
[
"url"
] |
[
"url"
] |
|
lxvr8b
|
Why does Sourdough Starter grow yeast but not other dangerous microorganisms like mold?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpp80ko",
"gpp8etl"
],
"text": [
"URL_0 TL:DR: > During sourdough production, bacteria convert the linoleic acid in bread flour to a compound that has powerful antifungal activity. Now, that said, they can and do grow mold if the starter isn't fed or cared for properly.",
"A sourdough starter is basically a symbiotic soup of yeast and bacteria. The yeast makes CO2 and alcohol, the bacteria make acid. The \"Tang\" in sourdough comes from the bacteria, specifically from lactobacter. Essentially, they create an environment that is hostile to other microbes. The acid from the bacteria makes it hard for other microbes to get established, as does the alcohol from the yeast. As long as you're careful when establishing the culture, and you feed it regularly, the microbes in the culture will take care of themselves."
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|
[
"url"
] |
[
"url"
] |
|
lxw1k0
|
Our brain uses about 10W of power, when a computer can use 100W. With our brain doing significantly more than a computer, how is it so much more efficient?
|
Technology
|
explainlikeimfive
|
{
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],
"text": [
"Your brain is nothing like a computer, architecture-wise. Computers use programs that are millions of simple instructions from a set of a couple hundred instructions. The brain is parallel, executing a few hundred instructions from a set of zillions of complex instructions you call \"thoughts\".",
"> with out brain doing significantly more than a computer Can your brain do millions of additions or multiplications per second? Your brain is not doing all that much in terms of raw logic.",
"The real answer is that billions of years of evolution have optimized biological organisms for energy efficiency. But in a sense, that doesn't really answer the question. *Why* are brains so energy efficient? I suspect one of the main contributing factors to be the way the brain is structured: it's very \"sparse\", in a sense that, at any given point in time, everything not currently needed is \"turned off\". You may have heard that only a small fraction of the brain is \"in use\" at any given time. What this means is that, in a sense, the brain is doing the minimal amount of work necessary - only updating state where it's relevant to the task at hand. Conversely, computers tend to be big and stupid and simple and full of logic gates that flip whether their results are needed or not. Modern CPUs have started selectively enabling and disabling parts of the hardware based on what's currently needed, but it's many orders of magnitude less sophisticated than what the brain is capable of doing. Also, despite almost a hundred years of engineering, transistors are still very energy inefficient. They don't just propagate state changes, they also waste a bunch of current in the process."
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[
"url"
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[
"url"
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|
lxwkl8
|
what causes trees to split? Do they just decide at 5 feet to say fuck it Imma head out?
|
Biology
|
explainlikeimfive
|
{
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"text": [
"It's because trees want to take a shape that works for them. Basically trees have five main things in mind. Keep anchored (which is the job of the roots), suck up water and fertilizer (also the roots), don't fall over (the roots plus the trunk), reach more sunlight (the branches and the leaves) and suck up sun for energy (the leaves). There's a lot of different ways that a tree can do all five, but it really can't do the fifth one very well unless it spreads out sideways a little (yes, there are exceptions like palm trees). The reason for this is the leaves get in each others way, blocking the sun. So as it grows, it splits, and this lets more leaves be in more sun because the tree starts getting more sideways as it gets taller. Now the tree COULD just keep trying to keep all its leaves and grow taller and taller without branching... but this starts making \"don't fall over\" a lot tougher at some point. So the tree branches to get more light once it gets to a certain size, and keeps branching after that to collect even more.",
"The top of the tree is in charge. It grows like crazy to get more sun and make more side branches. More sun and more leaves mean more sugar and trees like sugar too. Eventually the side branches can't hear that bossy top - they grow a little more and soon they're telling the buds behind them to grow more side branches while they chase the sun and make more sugar. Douglas Fir and Sequoia and Red Alder branches have really good hearing and only rarely subordinate. Lilacs and Hornbeam and Willow never listen. Trees that are topped go crazy - there's nothing to listen to.",
"At least for some trees, there are special cells (apical meristem) at the end of a stem. These cells produce a chemical (auxin) that stops other stems from branching. As the stem grows long, there is less of that chemical so other stems start to branch off. The first stem a tree has is the trunk. So after the tree is tall enough, a new stem branches off and the tree starts to get wider at the top. This happens again and again over time. As it grows taller, the older stems get bigger around to help support the weight. This is able to happen because the tree keeps its food and water movement cells just under the bark. Over time, these cells are made more rigid with other chemicals and new food and water movement cells grow on top of those. This is why we see rings when we cut into a tree also. This process usually happens on a yearly cycle, so we can often count those rings to know how old the tree is. This is important to your original question because those special chemicals from the ends of stems are pushed around by the food and water cells. That affects how much of the chemical is in any part of the tree and isn’t a perfect process. Since this is ELI5, I’ve definitely oversimplified. Someone linked a post in r/askscience that has the more technical names.",
"I don't remember much of the technical lingo from my Aboriculture class (Ecology, Evolution, Natural Resources Degree), but the simple answer is that usually one tree stem is dominant and this becomes what you know as the trunk. What will sometimes happen is a second stem will compete for dominance and both will grow around the same rate. This causes the split that you see. Sometimes those split trunks will even fuse together and form one larger trunk, which is better for the tree. Edit: still have my text and it confirms that whether or not a tree will actually split is due to genetics, but the reasoning above is accurate. Edit2: I'm not suggesting 2 trunks are better than one. I was just making a point that it's better for the tree if they fuse together, which is not likely. One trunk is always better. Arboriculture 4th edition -Integrated Management of Landscape Trees, Shrubs, and Vines by Richard Harris, James Clark, and Nelda Matheny.",
"Heres another interesting tidbit, trees can be made to split so you can harvest straight staves from them with a practice called pollarding: URL_0 Common practice in the middle ages I believe.",
"The most common cause of trees splitting is a defect inherent in a lot of tree species known as included bark. Basically, in a healthy branch union, the bark from one branch meets the bark from another branch and grows outward, forming the branch bark ridge. This normally happens in wide or U-shaped unions. When the union is too tight, or V-shaped, the bark from both branches meet and grows inward. Eventually, this will cause weakness or a split in the timber below. You can mitigate this by bracing, but it's rarely successful. The maintenance of bracing (as with most long-term plans for managing trees) needs to be multi-generational for the owners. More often than not, the brace is installed then forgotten about. Decay fungi can also cause failure, but this is more snapping than splitting.",
"Hormones, the different part of the trees have different hormones that control growth. When the top is growing, it produces hormones that aid the growth of the tip and at the same time tells the other nodes down the stem to keep in check. As the distance increases the hormonal control signal gets weaker and branches start coming out at branching points/nodes. They start producing their own growth hormones that slowly more and more overcome the restrictions of the main top. Then depending on environmental ok me branch can take over as the top might have hit environmental limits. Or in some tree species everything can be regulating everything and you have a great balancing act. Think giant round oak tree in a field. There are some great tests you can do, or read up on how bonsai artists use this knowledge when pruning their trees. They balance not just visually but also hormonally their trees."
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[
"url"
] |
[
"url"
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|
lxx9b7
|
- Why and how are babies so strong? What advantage does having a strong core give babies?
|
I’ve read a few things in the past that say that babies pound for pound are stronger than bulls. Also they seem to have ridiculously strong cores (abs) without training. Plenty of videos show them being able to hold their legs up over grass for large amounts of time when they don’t want to touch it. How are they able to achieve this without training? What advantage does this give them if they can’t naturally cling on to mom or dad?
|
Biology
|
explainlikeimfive
|
{
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],
"text": [
"This is explained by the square-cube law. In short, strength and durability are proportional to the size squared (X*X) and weight is proportional to the cube of the size (X*X*X) so if you take a human and shrink him proportionally to half size, he will become 4 times weaker but 8 times lighter, so in total it would be twice (8/4) as easy for him to lift his own body. Babies have different proportions and their muscles are less developed, of course, but still they are much smaller than adults so it's easier for them to do these tricks. Babies appear to have lots of strength, but it's realistically only in relation to their size. They are super good at clinging to their parent. Their strength doesn't \"go away\" as they age, it just doesn't grow proportionally to their size. They do get stronger as they age, but they get a lot heavier too so some of that \"innate strength\" (and the strength they gain) goes towards just lifting their increased bodyweight rather than feats of strength like holding their legs up easily.",
"Babies have bonkers grip strength for their size. The whole purpose is that they can cling on to their parent to move to safety if needed, and to develop the ability to roll or raise their head to avoid suffocating as early as possible."
],
"score": [
28,
10
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
lxy35e
|
why do teeth “hurt” when eating extremely sweet foods?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gppxko0",
"gpppikp"
],
"text": [
"Note that this isn't normal. It's generally a symptom of mild or moderate gum disease and excessive plaque, resulting in recession of the gum tissue. This is usually a result of a lack of flossing and/or poor brushing routine, but pain in this instance can also be caused by cavities. Either way if you have frequent tooth sensitivity to cold or certain foods, its a good time to see the dentist. When gums are unhealthy and receded, it exposes living tooth tissue, known as Dentin, in the teeth root area beneath the layer of dead enamel on the exposed tooth surface. Often this happens in the space between teeth due to plaque trapped there. Normally the enamel is the only exposed part of the teeth and the gums cover the dentin. However bacterial overgrowth can weaken the connection between the dentin and the gum tissue causing gumline recession. Sweets often contain citric acid as a flavoring agent. Bacteria in the mouth also are able to quickly break down sugars into lactic acid. These acids cause inflammation and irritation of living cells in the dentin. These send chemical signals in response to the central nerve in the tooth resulting in pain.",
"Sugar is fuel for bacteria. As they metabolise it they produce an acid that breaks down the enamel of your teeth. Bonus fact: Starch, i.e. potato, is also fuel for bacteria. And unlike sugar it won't dissolve quickly and can stay stuck in your teeth providing fuel for days. Brush after eating potato chips."
],
"score": [
21,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lxy4b4
|
How do harmonics on stringed instruments work?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gppsjat"
],
"text": [
"There are a lot of really good discussions online already, but what it boils down to is that the string doesn't only vibrate (oscillate) along its full length (the fundamental)—it also vibrates as if it was three strings each having a third the length, and also as if it was five strings each having a fifth the length, and so on and so on. The frequency of an oscillating string is inversely related to its length (other things being equal, namely density and tension). So a shorter string will oscillate faster and produce a higher frequency than the fundamental."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lxy9mw
|
What are the natural predators of humans? If there are none, why are there none?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gppok9u",
"gppngec",
"gppxr8m",
"gppnips"
],
"text": [
"A lot of people have commented as to why, but here's a short list of some animals who absolutely do still see us as reasonable members of their food chain: - large crocodiles - hyenas - some lions & tigers (you can find a Wikipedia page that tells you about the man eating lions and tigers - they end up documented) - polar bears Polar bears will actively try to hunt you if you aren't careful. Hyenas scout through African villages at night, looking for easy meals. The idea that nothing hunts us is an illusion granted to you by you living in relatively developed society.",
"Everything with teeth used to eat us, than we started winning at long distance running, than we had fire and tools. Which help. Go try and hang out with some wolves, we don't win that",
"Litterally everything was. But then man put stick on rock and now we litterally own the whole planet and go to war with ourselves because animals got too weak",
"Lions, Tigers, and Bears - oh, my. ... Actually lots of animals would eat a human if they found a dead one. But, animals aren't idiots and the track record of taking on the planet's apex predator who specializes in endurance hunting - just having a crowd of humans chase you until you die of exhaustion - isn't a path that most animals would go down on purpose."
],
"score": [
22,
16,
3,
3
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lxycs4
|
How are we able to track/predict if an earthquake will produce/create a Tsunami and in turn estimate how big the wave will be and how long it will take to hit a coastline?
|
There was a magnitude 8.1 earthquake off New Zealand’s coastline and a tsunami warning has been issued with predictions of how big the wave will be in places and when it will hit. How are scientists able to predict this? Edit: Grammar and spelling lol
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gppt4v9",
"gpq0rrp"
],
"text": [
"Seismometers measure how strong the amplitude is. If you have sensors scattered about, you can quickly determine speed and direction of the wave/energy as it passes over them. These pieces of information let you estimate when, where, and how big the wave might be.",
"In addition to comments below, there is a networks of buoys in the Pacific Ocean that measures wave height, wave velocity and sea level (and atmospheric details), and communicate this data back to the National Tsunami Warning Center via satellite. If you’re interested, search for DART buoys and NTWC."
],
"score": [
6,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
lxz6jt
|
why texans are getting huge power bills when they weren't using power during the outages
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gppt38s"
],
"text": [
"They have sliding billing systems. The people getting the big bills were \"lucky\" enough to have electricity when many people lost it. Their \"cost saving variable pricing plan\" turned out to be super expensive in this unusual situation."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lxzhxc
|
why the United States doesn't go bankrupt?
|
I saw this today: "The United States federal debt is forecasted to grow to a record 202% of the gross domestic product by 2051, the Congressional Budget Office reported on Thursday, reflecting healthcare and debt services cost growth. The national debt for 2021 is estimated at 102%." So I'm curious, if the U.S. is in so much dept (I think a lot of countries are?) How doesn't it run out of money?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gppuz30",
"gppwkeh",
"gpq4b2w",
"gpq4mkw"
],
"text": [
"Because debt payments are still manageable. There are plenty of people out there making $100k doing just fine with a $300k mortgage and $40k worth of car loans (so 340% of income). As long as the federal government continues making its monthly obligations, people will continue to loan them money.",
"A few things... debt that's 2x GDP is sort of like a person having a home mortgage that's 3x their salary -- and that's a pretty common guideline for home affordability. What matters is not the debt in terms of current time period, but what the repayment terms are. Clearly nobody could repay a mortgage that's 3x their income in a year, but it's not hard over 30 years. Similarly, the U.S. debt is manegable because it's owed over time, in the form of bonds with re-payment schedules that are often 10, 20, 30 years. The fact the U.S. dollar is stable and the government always pays back its debts means they can borrow at very low interest rates. And the government has additional benefits in that it could always raise taxes to help pay back debt, or literally print money to repay them. Much of the debt is because Republicans have focused on tax cuts rather than debt repayment (they only care about the deficit when Democrats are in power), and as a result tax rates are at historic lows -- especially for the wealthy. Raises those taxes back to where they were in the 30's - 80's and we could pay down the debt more quickly.",
"A nation's debt is not like a person's debt. Every dollar that exists in every American's pocket is \"US debt\" and if we ever made the national debt go to zero dollars for some fool reason, we wouldn't have an economy any more. National \"debt\" is used in this context in an accounting sense. It confuses people in the same way they get confused about the term \"fitness\" in an evolutionary sense. Debt is bad when you owe somebody money, but debt is not inherently bad when a country owes it's citizens money in it's own currency. To understand what it would be like to control a country's debt, imagine inventing your own currency. We'll call it \"StockCuriousbucks.\" You could pay your kids \"StockCuriousbucks\" to do chores, by writing \"1 StockCuriousBuck\" on a piece of paper and handing it to them. You could then demand that your kids give you 5 \"StockCuriousBucks\" a week or else they're grounded. In this way, you would make your kids do chores. If your kid did 100 chores, you would be \"100 StockCuriousBucks\" in debt, but this doesn't cost you anything. If you give out too many \"StockCuriousBucks,\" you can reduce their value. For example, if you give your son 1 StockCuriousBuck to wash the car on Monday, and your daughter 10 StockCuriousBucks to wash the car on Tuesday, your son will probably be mad. So it is in your best interest to keep your StockCuriousBuck debt growth steady, to maximize your ability to get your kids to do chores. That's all the government really cares about. If they print so much money that it demotivates the population because of all the inflation, that's bad. If they print so little money that nobody can get their hands on it and activate their productivity, that's also bad. So the debt rate is just trying to find the optimal number. The only way we'd \"go bankrupt\" is if we made dollars completely worthless (like Zimbabwe bucks) or we went too far the other way and experienced hyper-deflation (which happened in ancient times with gold-backed currency but doesn't really happen in the modern age.)",
"\"Debt\" and \"Deficit\" are different things and a lot of people seem to get that confused. 'Debt' is what the US owes to other countries. 'Deficit' is the shortfall between tax revenue and expenditures. (If there's more revenue than expenditures, they refer to it as a 'surpluss'.) Anyway, as far as the deficit is concerned, since that is what most people are concerned with (especially since healthcare was mentioned) there is no such thing as the Federal Government 'running out of money'. It cannot declare bankruptcy. Effectively, taxes are collected and then written off. (The fund are debited from the source bank account and exist only as a record showing that the tax was paid. The US Treasury doesn't deposit that money anywhere.) At the same time, the Treasury creates new money at the direction of Congress. If more money is created than collected, this imbalance leads to an increase in the supply of currency which eventually (not immediately) leads to inflation. To prevent that, another organization, the US Federal Reserve, collects interest on Federally backed bank loans and writes it off to remove it from circulation. (Some of that interest is used to pay the bills, payroll, fund other loans, but a specific calculated amount is permanently removed from the economy.) It seems a bit far fetched, but currency in the US is actually not a closed-loop system like a lot of people seem to think it is."
],
"score": [
35,
9,
6,
4
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
lxzker
|
How does a phone/computer process the power button being pressed if it’s off?
|
I tried google and all I got was “pressing the power button to turn it off won’t damage it anymore.”
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gppxtiq",
"gppy3s2",
"gppvgiz"
],
"text": [
"There are two basic solutions, but in both the button is really just a signal, it’s not the actual source of power to the entire device. In the first, the device is not 100% off, but rather there is a tiny circuit still awake drawing a **very** small amount of power, waiting for the button to be pressed. When it sees the button pressed, it will activate the rest of the machine into waking. The other solution has the power button run from the power source to a small circuit that is off until briefly powered up when the button is pressed. When it wakes, it will wake the rest of the circuitry and the device will power up. It’s kind of like someone listening for a bell to ring in a shutdown factory, when they hear it, they will start powering up everything in the building (lights, machinery, etc) and getting it all going. That little bell didn’t ’t do anything, but it woke up the one guy who could turn it all on.",
"For computers: When you power the computer, there's a single hardwired instruction to the CPU that is executed (a JUMP). It tells the CPU to load the first instruction of the BIOS. The BIOS is a chip with ROM memory that has the set of instructions, it first test if the devices are ok, and if everything is ok, it will load the first instructions stored on where it is booting (mainly the HD, but the user can also boot from another device, like a flash drive, or a DVD), those first instructions basically tells the the CPU where everything is stored, and then loads a program called bootloader. The bootloader will then load the kernel, and from there, the kernel will take control of the computer.",
"There's a little bit of standby power in every device, as long as it's plugged in. Pressing the power button completes a circuit; that circuit uses the standby power to energize other circuits, which energizes still *other* circuits until the device is operating at full capacity again."
],
"score": [
17,
4,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
lxzn6s
|
Why do people think artists like Edvard Munch or Van Gogh are amazing? I don't mean currently because obviously they are now famous but specifically how did they go from being regular people to people thinking they are masters? I've never understood the appeal and am honestly curious.
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gppwidt"
],
"text": [
"Van Gogh is outstanding. His ability to define shapes and light using rough color, to imply motion, line, form and depth with crude discernable strokes and strong contrasts with a simple palette is unparalleled. He conveys so much information in a limited scope that its hard to imagine anybody doing it better. He's like a musician of color Munch had some good ideas but I prefer kubin."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lxzyk7
|
What is an NFT?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gppyggl"
],
"text": [
"Nft stands for non fungible token. It is a way to digitally represent ownership of something digital (NBA topshots is a good example of this) backed by the same technology that underpins crypto currencies. It's called a block chain, and uses encryption and distributed computing power to validate all transactions. In other words, you can \"own\" a digital picture or video and have proof that you do, which cannot be copied or replicated."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ly0ims
|
- What’s the reason behind having Congress read the 628-page document aloud?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gpq2jxx",
"gpq48hz"
],
"text": [
"The GOP is trying to slow down passage of the bill so it doesn’t pass until after March 14, because that’s the date when unemployment insurance programs from the previous COVID relief bills expire and many millions of people will come off unemployment assistance provided by the last bill, causing economic havoc and widespread suffering under Biden’s watch. One step is they can force the bill to be read out loud, sucking up about a day of time. That’s the point of this. It’s an intentional slow down. That’s all there is to it. They have also stated they plan to continuously offer amendments that need to be voted on, non stop, as another delaying method after they finish reading the bill.",
"It *is* a huge waste of time, but only one Member of Congress needs to act to force it, and the Congresswoman doing so is crazy and wants to disrupt random shit so she can go home and say \"look, I stuck it to the establishment\". House Republicans are apparently getting fed up with her, but just because it means more busywork - they don't want the bills to pass either but this doesn't stop them, just slows them."
],
"score": [
13,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ly0qqu
|
How do health insurance companies determine what they'll cover?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gpq2qvl"
],
"text": [
"They make a calculation how expensive it is to cover each person and how likely each condition is to occur and price accordingly."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ly2t2c
|
Why do horses need horseshoes?
|
Horses in the wild seem to be perfectly fine without them, why do we need to put hunks of metal on their hooves?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpqg3kq",
"gpqfox9",
"gpqn6cw"
],
"text": [
"You don't need to if you only plan on having your horse on natural soft surfaces like dirt. If you are riding your horse on rocks, asphalt, concrete, etc. Then you need shoes.",
"You can run horses without shoes and their feet will be tougher. But just like your feet, they will be more protected and less work than going barefoot To answer your question... horses don't NEED horseshoes, just like humans don't NEED shoes. But it they make life easier",
"Horses on the plains run on mostly soft soil with patches of rough hard ground and do not have weight on their backs. When we use them as mounts or to pull things they are often walking are harder surfaces than they naturally would and carrying far more weight than they naturally would."
],
"score": [
21,
12,
8
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
ly3152
|
What is happening in your body/brain/etc the first few seconds you wake up every day?
|
If that makes sense, like when you first wake up on a given day, what processes and activity is happening in your brain, organs, etc. Is your brain literally saying come on let's go, wake up? What about if you're woken up abruptly like in an emergency, loud sound, etc?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpqjrja"
],
"text": [
"For a step by step of what is going on, we truthfully don’t know. A lot of what our brains do, both when awake and when asleep, is still a mystery. We’ve figured out what sections seem to relate to what actions/activities. But how the hunk of meat actually turns electrical impulses into everything we experience. We still don’t know. We aren’t even 100% sure why we NEED to sleep. But for general stuff, to start, your brain is never completely “off” or shut down. It is still active and processing sensory inputs (hence loud noises, bright lights, or being shaken wakes you up). So it’s not like the brain is completely shutting down and booting back up like a computer, it’s just going into, well, sleep mode, like a computer. There are some processes we do know about, such as the paralysis our brains put over our bodies to keep us from moving around in our sleep. Which is what causes some people to get “sleep paralysis” when they wake up in the morning where their mind is awake, but the brain hasn’t yet unlocked that paralysis and you can’t move your arms/legs yet."
],
"score": [
7
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
ly3419
|
What’s the difference between thinking about moving a body part, and actually moving a body part?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpqjko8"
],
"text": [
"The difference is that if you're just thinking about moving a body part, the impulses that would travel down your spine and to the body part in question aren't ever sent."
],
"score": [
6
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ly36bq
|
how do people own million dollar houses but don't have a million dollars
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gpqhfrw",
"gpqilwx"
],
"text": [
"Loans. If you have a combine family income of $175,000 a year, you can easily afford payments on a million dollar or more loan.",
"Loans. (Credit) The Bank estimates that you are worth enough currently and will continue to make enough money to be able to pay back a loan that far exceeds your current net worth. They give you the money to buy a million dollar house. They own the house and you pay them \"rent\" (loan payments) until you pay off the amount you borrowed. This is not always the case, which is what led to the 2008 financial crisis due to banks not caring to make sure people could pay for the loans they were coerced into with pipe dreams and snake oil. So, in closing, some people can afford to pay for 30+ years to own their million dollar home on a mortgage loan from the bank. Most of them did it when that million dollar house they now own cost them 50K. The housing market is and will continue to be super volatile. Land is equity, the house on it is not guaranteed to be."
],
"score": [
9,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ly3sen
|
How does touch-screen work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gpqlqwr",
"gpqlvqx"
],
"text": [
"(I hope this doesn’t sound condescending or pretentious, I’m literally gonna try explaining like you’re five, not that this is an easy or intuitive thing to understand) Throughout our bodies we have nerves and they send electricity to our muscles and makes them move and flex, when we touch a touchscreen like on a smartphone it senses that electricity in our bodies, it’s not a lot of electricity at all so you don’t feel it, that’s why objects that don’t have any electricity or block electricity from reaching the screen, it doesn’t work. Older or lower budget touchscreens that you might find in a convenience store or sth have pressure sensors when you press down on them in a certain spot it senses that.",
"Oh! I actually kinda know this! Most modern touch screens use whats called Capacitive touch. This means that the device can measure the electrical interference that you generate when you touch the screen. This interference is interpreted by software to a location on the screen, where it puts the pointer."
],
"score": [
4,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ly3whg
|
Why does water taste so good after a nap?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gpqpwn2"
],
"text": [
"We lose water from sleeping, we wake up and our body says \"golly gee I sure am thirsty\" so when you drink water your brain rewards you with the good chemicals"
],
"score": [
9
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ly4km3
|
- Why are most movies released at 24fps?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gpqqbdm",
"gpqq0xo"
],
"text": [
"Silent movies would be shown at pretty much a random frame rate, because they were literally done by someone turning a crank on a projector and it was almost impossible to get the frame rate consistent. When \"talkies\" came along, though, the sound was recorded alongside the film and had to be played back at the right speed or else it wouldn't sound right, so a standard frame rate was needed. AFAIK it was Warner Bros with their \"Vitaphone\" system who chose 24 fps--it was picked because it was fast enough for smooth animation, but didn't use enormous amounts of film stock (which was very expensive at the time). 24 is also easily divisible, so it's easy when editing a film to know that a third of a second is 8 frames, for instance--important when you're having to physically cut out frames and stick them back together!",
"24 frames per second is the slowest that you can film without introducing noticeable flicker. Film stock is expensive and so movie makers want to use as little of it as possible. If they could get away with it they probably would have filmed even slower. In these days of digital recording you can much more easily and cheaply record at higher frame rates but people have become used to 24 fps and see anything faster as \"off\". For example, TV shows recorded on tape are at about 30 fps and people associate this frame rate with cheap production values. It's called the soap opera effect."
],
"score": [
12,
9
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ly4koe
|
why do you need to cook chicken fully through but duck is best cooked to medium rare?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpqpt1i"
],
"text": [
"Chickens are raised on factory farms where it's really hard to avoid dirty, unclean conditions. In these conditions salmonella can easily spread. Ducks aren't usually raised this way so salmonella is significantly less of a risk. But, it's still a small risk."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ly4nxf
|
Why can feet/hands be cold, but still sweat?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpqs9qp"
],
"text": [
"Your body has to try and keep your organs at a working temperature, so at various times it will do things to increase or decrease heat. If you’re too hot you will sweat. If you are too cold your hands and feet will lose blood flow because blood cools down as it moves down your limbs. If all the blood stays in your core you stay warm for longer. But you **FEEL** temperature on your skin too. Only trouble is, you don’t actually have a thermometer in your skin. You don’t “feel” temperature. You feel how much heat is leaving or entering your body. If a lot is leaving, you feel cold. If a lot is entering, you feel hot. You can imagine a scenario where your body as a whole needs to cool down, and is sweating, but your legs could FEEL cold as that is where the heat is exiting your body into the environment. I could be freezing cold, but still burn my leg on a soldering iron because too much heat would be entering at once. This is why metal and liquids “feel cold”. Even at the same temperature as the air, they transfer heat better than air does. So when you touch a room temperature metal object, it quickly sucks heat from your body. (Feels cold). Where another object at the same temperature wouldn’t take so much heat, and wouldn’t “feel” cold, even at the same temperature."
],
"score": [
7
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ly4weg
|
why are rainbows only curved?
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gpqry8q"
],
"text": [
"Rainbows are actually circular but because we see them from the ground we typically only see half of them. If you view a rainbow from an airplane you can see the whole circle. But why? Light spreads out a bit, and it does so consistently and evenly. Consider a flashlight shining on a wall ten feet away: the small circle of light spreads out into a large circle of light. That's sort of what we're seeing in a rainbow, that expanded circle of light as it passes through airborne water."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ly4xyg
|
how does remastering old videos which had a lower resolution into HD or a higher resolution work?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gpqrywl",
"gpqs5lv"
],
"text": [
"It was shot on physical film. Film doesn't have a resolution the same way that digital video does. And it captures a lot of detail, so you can scan it in 4K no problem.",
"URL_0 If the original was only on video then nothing you can really do since the higher resolution doesn’t exist. It may look slightly crisper with better color correction via computers. As an example, some of the original Honeymooners tv series were only saved on a fairly new and primitive video system and looks like pure crap because there’s not a ton you can do when the source recording is poor quality."
],
"score": [
8,
3
],
"text_urls": [
[],
[
"https://www.reddit.com/r/explainlikeimfive/comments/1w6vms/eli5_how_are_old_films_digitally_remastered_into/?utm_source=share&utm_medium=ios_app&utm_name=iossmf"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
ly5hui
|
Is there any actual scientific reason why we drink so much water when we wake up in the middle of the night?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpqutja"
],
"text": [
"Everytime you breathe you exhale moisture in your breath. If you breathe through your mouth you exhale much more moisture than if you breathe through your nose. Depending on multiple factors you might breathe through your mouth more when you're sleeping and so lose a lot of water. When you wake up you're thirsty because you've lost so much water."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ly5i9r
|
How does Helium escape from party balloons?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gps80jb",
"gps8j4o"
],
"text": [
"Helium atoms are smaller than the molecular make-up of the ballons. They in essence slip between the cracks. Add to that that most traditional ballons are elastic and forced to expand under pressure meaning the helium is always trying to find a way to the lower pressure on the other side of the balloon wall. Mylar balloons on the other hand are made up of material more impervious to the leaking Helium. Add that they are mostly pre-inflated, so once enough helium leaks out they can hold the gas at a much lower pressure.",
"Helium is the smallest “molecule.” It’s a single atom, compacted by a relatively high nucleus charge/size ratio. It’s so small and so chemically inert that the gas molecules can escape directly through the balloon material, wiggling their way in between other much larger molecules on their quest for freedom. So no matter how well you tie off the bottom, the helium will eventually escape a cheap latex balloon. Materials with more compacted molecules like mylar will hold it longer, but even that is only slowing the inevitable."
],
"score": [
5,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ly66ae
|
What is the crunchy sound you are hearing when a hard drive is reading and writing data?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gpqyfel",
"gpqydod"
],
"text": [
"Take a look at this diagram of a hard drive. URL_0 The hard drive consists of spinning metal platters, a read head that overs over those platters and an arm that moves the head into position. The crunching sound you're hearing is the arm moving the read head into various positions very quickly. That's why you hear it more when doing lots of small reads or writes. If you're reading or writing data sequentially then the arm doesn't have to move so much and you don't hear the sound.",
"Inside a hard drive specifically (hdd not ssd), is a little disc, beneath an arm kinda like a record player if you think about it. So when something says that it's writing, that information is being recorded on tiny moving parts (correct me if someone knows this is wrong, it's just how I was taught). This is what makes the scratchy noise. This is also why hdds are much more common to fault, as opposed to solid state drives (ssd) that have no moving parts"
],
"score": [
15,
5
],
"text_urls": [
[
"https://www.bhphotovideo.com/explora/computers/tips-and-solutions/anatomy-hard-drive"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
ly6f1c
|
How do VPNs work?
|
I understand there are general concepts like Full and Split tunnel, I just can’t grasp the concept according to textbooks. What makes different models...well, different?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gpr01hp",
"gpr4cm0",
"gpr4ett"
],
"text": [
"i'magine your computer is your home. regular, unprotected connection to the internet is done by using your front door or window... everyone can see when you come, when you go, and if you have visitors or deliveries. using vpn's is like digging a hole into your neighbors baseement (with permission) and you use their front door/windows. While using your neightbors isn't that much improvement, it makes it harder for anyone to say it was you doing comeing and going. But VPN are much bigger than that... you're neighbor is a bad ass, and the entire neighborhood has tunnelled into their basement and their activity obscures your activity. now mix in some encryption... basically anyone and anything that comes/goes at the frontdoor/windows is always in the shape of an ominous black box.",
"Assuming you know how a vpn works in general, the difference between a full tunnel and a split tunnel is how much of your data goes through the VPN. In a split tunnel, only data going to a certain network/location/server etc actually goes through the vpn. The rest of your internet traffic goes straight to wherever its going. A full tunnel means that every bit of data that leaves your computer to somewhere on the internet goes through the VPN first.",
"The internet works like the post system but faster. Instead of sending a letter directly and having the post people see who you're writing to you put your letter in another envelope and adress it to some VPN company. They open the letter, find your letter already adressed to the actual receiver. They write their own adress on it to tell the receiver who they should answer. So you basically put an instance between you and the receiver. The receiver won't find out your adress, and the police can only find out who you're talking to by going to the VPN with a warrant (and some are obviously out of their juristication, or simply keep no records at all) And as a bonus: TOR network works exactly like this too, but instead of just using one middleman you put your letter in 10 envelopes that are locked and can only be opened by the correct next middleman. So noone at the start of the chain can find out who the receiver is, and at the end noone knows who the sender is."
],
"score": [
11,
5,
5
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
ly6paz
|
What is tidal heating?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gpr1b6y"
],
"text": [
"The tides are caused by the moon pulling more strongly on the near side of the Earth than the far side. More generally, tidal forces are when gravity pulls more strongly on one side of an object than the other. When objects orbit one another, these forces cause a sort of circular squishing motion, which on Earth produces the high and low tides. This force is experienced even by solid bodies, and through friction and slight motion this generates heat. Due to just how monstrously huge planets are, this heat is actually significant sometimes."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
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