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lt6c4i
Where does body heat come from? How does the body know what 97-99 F is and keep it there? Is there a body heat organ, or is it done everywhere?
Biology
explainlikeimfive
[ "govmnvy", "govo6hm" ]
[ "Your cells 'burn' glucose and oxygen to power themselves. This produces heat. Your brain subconsciously knows that your cells will die outside a very narrow temperature range, so you sweat and breathe to regulate your temperature." ]
[ 10 ]
[ [], [] ]
[ "url" ]
[ "url" ]
6yb611
How did the Eagle Creek Fire in Oregon jump all the way across the wide Columbia River and start burning in Washington State?
Other
explainlikeimfive
[ "dmm24k9", "dmm0t2s" ]
[ "It was most likely a spot fire. Dry conditions and large gusts of wind can cause embers to leap and travel through the air hundreds to thousands of feet. I was a wild land firefighter for two seasons, and spot fires are something we are taught to be very wary and cautious of." ]
[ 7 ]
[ [], [] ]
[ "url" ]
[ "url" ]
6sxw03
Why does the United Nations predict a world population of only 9.8billion by 2050 and 11.2billion by 2100 (~32% and ~49% growth) when we have historically experienced eight times those rates with less starting population, less technology, and multiple world wars and epidemics?
[Source]( URL_0 ) It seems blatantly obvious these numbers will not be correct, possibly 100% wrong by 2100. Please enlighten.
Culture
explainlikeimfive
[ "dlgfwkm", "dlge8dp" ]
[ "Demographic transition. It's the process where people start out poor and with poor medical care. Everyone has lots of kids. Most kids die before the age of 5. The limits on land keep overall population in check; if there are too many people there are famines or plagues. Science comes into the picture. And education. The death rate falls due to improvements in food supply, sanitation, and medicine. Population increase rapidly. People then stop having so many kids, and the birth rate falls and gets close to the death rate, due to contraception, increased urbanization, and a reduction in people living of subsistence agriculture that need kids to take care of them in old age (if you have social security or other pension checks, you don't need to rely on your kids to make sure to feed and care for you when you are old). Population stops growing (or even starts shrinking). So much of the West has already gone through this, and other countries are going through various stages." ]
[ 9 ]
[ [], [] ]
[ "url" ]
[ "url" ]
8yzttn
Where does the energy go if a solar panel is in the sun but isn't hooked up to anything?
Technology
explainlikeimfive
[ "e2ezts1" ]
[ "if im not wrong, it \"stays\" inside the silicon cells in the panel. basically the electrons cant flow because there is no circuit to flow through, so they are released but never used. i suppose they just recombine with other silicon atoms. edit: pretty much into heat. nothing more." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
m4asqb
How does a game like RDR2 spend 7+ years in development and release with such advanced graphics technology
When they started writing game code ~7 years ago didn’t they need to lock themselves into an engine? And wouldn’t that game engine be outdated visually by the time they release the game?
Technology
explainlikeimfive
[ "gqth2q8", "gqthoay", "gqtrdep", "gqtuv9i", "gqtt45t", "gqtyuuy", "gqtretb", "gqtfvun", "gqtfobn", "gqu0872", "gqu61bu", "gqv154d", "gqu00w3", "gqubm23", "gqu0u50", "gqu2uj4" ]
[ "game devs often interact with hardware devs and have access to development kits, with features not yet available to the public [projects have tanked because of poor communication/choices between devs and the hardware folks]( URL_0 ) > Timing and industry changes turned to trouble for Prey. It was mostly developed on the 3DFX card and the Glide API (\"It was the hot shit API of the day,\" Schuytema says) but internal troubles at 3DFX hit just as the Prey team was ready to go all-in with Glide. Meanwhile, Microsoft was getting its Direct X API off the ground. The team moved away from Glide, and ended up going with Direct X instead." ]
[ 1320 ]
[ [ "https://www.gamesradar.com/22-years-3-developers-only-2-games-the-fascinating-history-of-the-prey-series/" ], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [] ]
[ "url" ]
[ "url" ]
7p47uc
How do surfers speed up to escape a crested wave?
I was watching [this video]( URL_0 ) from /r/UNBGBBIIVCHIDCTIICBG/ and several times it looks like the surfer is going to be caught by the wave, however she seems to speed up and escape without doing anything significant other than a slight 'wobble' after she's escaped the crested part of the wave.
Physics
explainlikeimfive
[ "dsegiwn" ]
[ "It's mostly unweighting off the bottom of the wave, the \"flats\", and hopping the board up onto the face of the wave, even ever so slightly like you see when she is near the white water. By unweighting and getting the board up, she can then redirect the board down and use both gravity and the push of the wave from behind to generate speed. There may be other subtle factors, like if she's riding a three fin board they create a bit of drag when going straight and release when turned using two of the three fins, but it's mostly the unweighting, hopping up, and coming down to make speed." ]
[ 5 ]
[ [] ]
[ "url" ]
[ "url" ]
asozu7
Fur on coat hoods?
I know in arctic/antarctic climates, people wear coats with fur around the opening of the hood to keep their breath from freezing on their face. Why/how does this work?
Other
explainlikeimfive
[ "egvoa36" ]
[ "Pretty much the same way that fur works in general. One of the best insulators is just plain old air. Heat transfers in a few ways, but the one you're going to run into most in cold environments is conduction, where your warm stuff is touching cold stuff (air) and some of your energy leaves to the cold air. Insulation helps slow this down by having a barrier between your warm skin and the cold air. The less stuff is touching, the less heat can be transferred. Air isn't very dense, so it takes a while to transfer heat. The cold air in the arctic is *really* cold, though, and because it's windy it's always moving the relatively warm air away and replacing it with more *really* cold air. Fur traps some air around your skin, so the wind can't blow it away as much, and that warm air acts as a barrier against the much colder air so you don't lose as much heat. Around your face, the super cold air is cold enough to freeze the moisture in your breath as it leaves your mouth and nose. With the fur air barrier, it's *just* warm enough that the moisture has time to get away from your face before freezing." ]
[ 7 ]
[ [] ]
[ "url" ]
[ "url" ]
moemz1
Why do streaming services/websites restrict viewing content based on region?
Other
explainlikeimfive
[ "gu38o01" ]
[ "Here's an example... The new Star Trek shows are produced by CBS / Paramount. Therefore in the US, they are only able to be viewed on Paramount private streaming service. However, they don't offer this service in other parts of the world... so they sell the rights to broadcast those shows to Netflix outside of the US where they have no service of their own. Another example it's in the UK, where everybody pays for the BBC as part of their television tax... But they want to make sure that only those were paying get the service. Therefore they don't allow broadcasts of many of their shows outside the UK, other than through services that have paid the BBC for the rights to rebroadcast." ]
[ 6 ]
[ [] ]
[ "url" ]
[ "url" ]
8b8qwq
How are songs from concerts recorded, considering the sheer amount of background noise from the crowd?
Take for example this video: URL_0 (AC/DC concerts are a riot!). How is the audio so clear considering the sheer number of people in the background?
Technology
explainlikeimfive
[ "dx4s5vf", "dx4vy45" ]
[ "The audio is recorded straight from the source. So the mic's, guitars etc all go straight to the sound board and are recorded from there." ]
[ 13 ]
[ [], [] ]
[ "url" ]
[ "url" ]
bwwwwk
How does a Minecraft computer work?
Like how does it have memory, and be able to run applications and and what sort of functions can they do and how?
Technology
explainlikeimfive
[ "eq10vbk", "eq1990g" ]
[ "Minecraft has something called redstone, which is able to simulate most logic circuits and electrical circuits. So you could theoretically build anything electronic that doesn't include audio or video circuitry. (Although there are sound blocks, so there is a limited midi type music capability.)" ]
[ 11 ]
[ [], [] ]
[ "url" ]
[ "url" ]
6zy2p9
What is a single payer plan?
Economics
explainlikeimfive
[ "dmywv01" ]
[ "In healthcare circles, it means that one entity pays for your healthcare (the government). This can mean that the hospitals and doctors work for the government (like the UK's NHS), or it's a mix of government and private practice where the government pays the doctors directly (Canada uses this model). In the US, an example of Single Payer is the Veterans Administration (VA)" ]
[ 16 ]
[ [] ]
[ "url" ]
[ "url" ]
g2mon9
What is the science behind laughter?
Biology
explainlikeimfive
[ "fnmdofz", "fnn2vod" ]
[ "If you mean \"why do we laugh\" It is hypothesized that laughter developed in great apes as a way to diffuse socially tense situations. As our ancestors became more social and living in groups, it became more crucial to be able handle social problems even before speech developed. Laughter is believed to be a way individuals can acknowledge and try to move past an embarrassing or tense situation. Laughing together also builds bonds. If you mean \"what are the mechanical/chemical systems that happen in our bodies to create laugher\" I haven't the slightest clue." ]
[ 7 ]
[ [], [ "https://www.youtube.com/watch?v=Ov-kXSS1_yc" ] ]
[ "url" ]
[ "url" ]
f0j9qh
How come videos viewed the first time seem to take longer than the second time?
Other
explainlikeimfive
[ "fguh4gp" ]
[ "The first time you watch something, the brain basically says, \"hey this is new, I'm going to take in as much as I can about it.\" So it is more mindful to the content being shown. After seeing it once, the brain sort of \"remembers\" it and doesn't pay attention as much. Which is how things seem shorter. Your brain isn't processing it as much as it did the first time." ]
[ 4 ]
[ [] ]
[ "url" ]
[ "url" ]
o8c7dj
why can you touch both sides of a 9V battery, you can even do it with a wet tongue and hardly get shocked, but a taser with that same battery can knock you out?
Chemistry
explainlikeimfive
[ "h342f1z", "h3430lf", "h342494" ]
[ "Tasers use circuits to * increase the voltage (some models go to 50 000 volts) * store the electricity from the battery in capacitors that can build up a charge over time and release it all very quickly There are DIY taser type circuits on line if you want to see what the circuits can look like" ]
[ 15 ]
[ [], [], [] ]
[ "url" ]
[ "url" ]
5v12xk
Why do houses make creaking noises at night for no apparent reason?
Physics
explainlikeimfive
[ "ddyeko1" ]
[ "It's impossible to say what the cause is in your house specifically, but there's a few things that could be going on here. Note that it's likely that the same creaking sounds are being made during the daytime, too, but there's more going on and more other noises - at night, it's quieter, so you're more likely to hear and notice them. If you're in an area where it's cold, it's colder at night. This may cause sounds as moisture in the house itself gets colder or freezes, and as the ground freezes and causes things to shift. Wind may cause the house to shift slightly and make creaking noises. A burglar or murderer may be slowly sneaking through your house, causing creaking noises as he/she steps on creaky boards. Point is, there's a lot of little things that can cause structures to shift; the ambient sounds that're always there are going to be more noticeable when you're more able to focus on them." ]
[ 7 ]
[ [] ]
[ "url" ]
[ "url" ]
hxttgm
Credit Cards (first-time user)
Other
explainlikeimfive
[ "fz8gt75", "fz8h29o" ]
[ "> What do I need to do to \"build credit\" and make sure my score is goes up? Use the credit card to buy stuff you normally do. Not more, not less, just normal spending. Pay that amount off at the end of the month when your payment is due; pay it in full and on time. Do this for a while and your credit score will go up. > How do I not fuck up? There are various ways to keep track of your bill due date such as reminder emails. You can monitor how much you have spent online or with phone apps, so never let the amount you owe go over what you know is available to pay for it. > What should I be checking? That your spending is within your means (no more than with your debit card) and that you make your payments on time every month. > When should I use my debit card versus my credit card? *Always* use your credit card. There is no reason not to and several reasons to do so. One major reason is that suppose something goes wrong like your card information gets stolen and fraudulent transactions are processed. With a credit card that is a bill you don't owe; dispute the charges and the charges are immediately put on hold (you don't need to pay them) and eventually will be removed. With a debit card you just had money stolen from you and you will never get it back. Paying with a credit card also contributes to a better credit score, while paying with a debit card does nothing for you. It just exposes you to more financial risk." ]
[ 12 ]
[ [], [] ]
[ "url" ]
[ "url" ]
5ux0lb
Why is Tony Blair getting hate for the Iraq War now more than during the war itself?
Maybe I'm missing something, but everyone in Britain seems to be bringing up Blair and the Iraq War out of the blue as if they realised recently that the war was a mistake. Countless people in the country, and worldwide, we're against the war when Britain went in. Why is Blair getting blamed again all of a sudden when the war was in the early 2000s?
Other
explainlikeimfive
[ "ddxjpqz" ]
[ "Because various reasons were given before and during the war to justify British involvement such as alleged WMD's, Iraqi freedom and combatting terrorism. Now we know there were no WMD's, hundreds of thousands of Iraqis have died and are still suffering through civil war and terrorism is arguably a greater threat to the UK than it's ever been. The power vacuum caused by the collapse of the regime allowed the Islamic State to suddenly arise and capture huge territories which is a relatively recent event. As for Tony Blair, well, it was ultimately his decision to commit to the invasion and now that it can safely be called a disaster and he's no longer PM some people feel he needs to be held accountable for that, some even going so far as to brand him a war criminal. The Chilcott Inquiry found that the invasion was ordered with little or no decent intelligence to support it and that peaceful options were largely ignored. That Inquiry finally concluded in 2016 after 7 years which might also explain why you're hearing more about it now." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
a7hbtz
How are music and audio recordings synced in the music videos?
Technology
explainlikeimfive
[ "ec33gm9" ]
[ "The finished audio recording of the song is played back on loudspeakers during filming. It’s loud, and there’s plenty of noise on set from foot steps, fans, directors comments, etc. The audio from the film is replaced by the officially released recording during post-production. Even if it wasn’t, video editors are advanced enough these days to be able to slide each clip forward or back to line it up with the music track, and then stretch or compress the length of the speed happens to be off. As an additional benefit, most music these days is recorded to a metronome (click track) at a known tempo, so everything should be performed in the video at the same speed." ]
[ 4 ]
[ [] ]
[ "url" ]
[ "url" ]
5q6cod
Why are boats in drydock propped up in the air with blocks of wood? How is that stable?
Other
explainlikeimfive
[ "dcwo0pv" ]
[ "The bottom of 1/4 the boat is substantially heavier than the top 3/4 of the boat, like a weeble-wobble if-you-will, the blocks are laid out in such a way that a stand set on one side will have an identical stand on the opposite side with a chain linking the two together. As the boat is lowered from the lift, the bottom of the boat comes in contact with the stands/blocks, if the blocks want to move outward, the tension of the chain keeps the block from moving any further." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
lwunei
Why do humans show teeth when happy, while every other animal shows teeth to threaten?
Biology
explainlikeimfive
[ "gpjagv4", "gpjcg9w" ]
[ "Some primates show teeth to be submissive... “I am not a threat to you.” Maybe we offer toothy smiles to show we mean no harm." ]
[ 9 ]
[ [], [] ]
[ "url" ]
[ "url" ]
6yvjtw
Why, when gently pushing or lifting something that has been sitting on a surface for a while, is it "stuck,"?
I just tried it with some things on my desk, but didn't find a good example, but for something like a plate that has been sitting on the table for a day or two, you can go to slide it with your fingers, and it will resist just a tiny bit, but after you break it free, it slides with no problems. What's the deal?
Physics
explainlikeimfive
[ "dmqqb57" ]
[ "Lots of furniture has a shellac or varnish on it that plates can slightly sink into if left on them for long periods." ]
[ 9 ]
[ [] ]
[ "url" ]
[ "url" ]
6zt3gn
Why does a dead phone have to charge before booting, while a dead laptop will turn on right away?
Repost
explainlikeimfive
[ "dmxv6t0", "dmxu8ns", "dmxwl7r" ]
[ "Your laptop is designed to run from 2 power sources: 1) battery 2) direct from AC power adapter Your phone can only run from the battery, and therefore always needs to wait for the battery to reach a minimum charge." ]
[ 13 ]
[ [], [], [] ]
[ "url" ]
[ "url" ]
gm26sa
Why aren't objects bent in videos where the frequency of said objects is the same as the camera shutter speed?
The title won't make sense if I don't explain as I barely understand the basics. I have recently learned about the rolling shutter effect from this video: URL_1 I have seen several posts here on reddit illustrating what happens when the camera shutter is the same as for example the blades of a helicopter. I get that the blades appear to not move but why I don't get is why the blades aren't frozen and also bent as seen in the rolling shutter effect. Example of helicopter blades for example: URL_0
Technology
explainlikeimfive
[ "fr12ddd" ]
[ "The rolling shutter effect is only visible in certain conditions. Some more expensive cameras have a global shutter option instead of a rolling shutter. And whith a global shutter you do not get the rolling shutter effect. Another way to get rid of the rolling shutter effect is to increase the shutter speed so there is less movement in the frame as the rolling shutter is moving across it. So it is quite likely that they have used camera settings that does not show the rolling shutter effect when filming the helicopter blades. Either they are using equipment with a global shutter or they are filming it on a bright day with a faster shutter so the effect is not so visible." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
grvvlb
How is a university given its rank?
Other
explainlikeimfive
[ "fs1fv9y" ]
[ "Number 1 at what? On what list from what source? There isn't any \"official\" ranking source. Rankings from source to source may take different criteria into account. Things might include exclusiveness (low accept rate, high GPA and ACT/SAT), lots of quality research being done, big sports program, big funds available for future projects, grad success in finding jobs, etc." ]
[ 4 ]
[ [] ]
[ "url" ]
[ "url" ]
dkyl0p
I've heard that stretching out our hands on a balance beam increases our balance, or putting two weights on the ends of a pole while walking on a tightrope makes it nearly impossible to fall. How is this done, what's the physics behind this?
Physics
explainlikeimfive
[ "f4kmmr9", "f4kp9sn" ]
[ "So this is to make your mass spread over a much wider area. What this allows the brain to subconsciously do is to detect when things are moving out of balance and counteract the motion. If you are holding onto a pole horizontally, you can observe the ends of the pole start to move out of 'balance' waaay before the point where you would fall. It also allows you to make much smaller movements to correct your balance. Doesnt make it impossible to fall, just makes it a lot easier to realise you are falling and correctly do something about it." ]
[ 40 ]
[ [], [] ]
[ "url" ]
[ "url" ]
fvzrz4
How do anti-plagiarism detectors and programs work to find exact wordings from other sources and determine that they aren't just coincidence?
Technology
explainlikeimfive
[ "fmlebsl", "fmlqc1m", "fmlcq5i", "fmlcyp1", "fmm69q5" ]
[ "It is VERY rare for a single sentence to be repeated by random chance. The odds of an entire paragraph or page being copied are zero. To give you some context. I've written several 100,000 word books. Often I'll think to myself \"Oh, I need to edit this section or that section\" and I'll use the search feature. If I can remember one or two words from the section I want to find then there are never more than 3 hits and usually its just 1. If you want you can test it out with an online bible. If you remember any few word you can usually immediately find the bible verse you were thinking of. plagiarism software shouldn't (and almost never is) used to try and find one sentence in a multi-thousand word essay. It looks for patterns of behavior where big blocks of text have been taken from a handful of sources. And that just never happens honestly." ]
[ 28 ]
[ [], [], [], [], [] ]
[ "url" ]
[ "url" ]
c3jkx5
Why the sudden disparity in chromosome number despite difference in complexity and intelligence?
Human: 46 Adder's tongue fern: 1,200 Cultivated Tobacco: 48 Einkorn wheat: 14 Fruit fly: 8 Kingfisher: 132 Goldfish: 100-104 & #x200B; I would expect humans, elephants, blue whales, and other more complex organisms to have more chromosomes than things like ferns and goldfish. So.... why? I mean, what's chromosome number determined by? Why does the Adder's tongue fern have approximately a thousand times more chromosomes than goldfish?
Biology
explainlikeimfive
[ "errfhzg" ]
[ "Just because a book has more pages doesn’t mean it’s a better book. Chromosomes in different species do a lot of different things, and some are more or less efficient, some specialized and some not. The number of individual chromosomes (out of context of a species) is unrelated to pretty much anything" ]
[ 9 ]
[ [] ]
[ "url" ]
[ "url" ]
7bmitw
Difference between beat, bar, steps, tempo, tact, and rhythm.
Other
explainlikeimfive
[ "dpj575y", "dpj8p12" ]
[ "Many of these have multiple meanings, these are the ones I run across most often. Beat: a length of time. This is used nonmusically as well, “step on stage, give a beat, then deliver your line”. In music is it usually the pulse that you can clap to. In 4/4 time, for example you get 4 beats in your bar. Bar: a bar is a logical collection of beats. Bars usually get 3 or 4 beats, but other options are possible. Step: I usually see this in composition programs. It is common to have a run of notes that are all the same length, for example 8 sixteenth notes. The step is the distance between each note. If you were notating this, you want to step at sixteenth notes. You typically set your step to eighth notes or triplets or quarter notes. Tempo: how fast the beats happen. Usually measured in “beats per minute” or BPM. Rhythm: this is the collection of notes in the music. Take all the notes in a phrase, and that is the rhythm. Tact: I have never heard of this." ]
[ 50 ]
[ [], [] ]
[ "url" ]
[ "url" ]
ew0loo
When your on the phone and it's on loudspeaker whats stopping it from echoing back?
Technology
explainlikeimfive
[ "ffz40xb", "ffzbimj" ]
[ "Modern smartphones, since at least the Nexus One, have a secondary microphone. This microphone detects 'ambient' noise in an attempt to limit what the primary microphone actually sends to the distant end. When you put the phone on speaker, this microphone picks up the output from the speaker, so it's flagged as 'ambient' by the audio processor." ]
[ 7 ]
[ [], [] ]
[ "url" ]
[ "url" ]
8l4avp
Have other languages changed as dramatically as English has over the last 1000 years?
Culture
explainlikeimfive
[ "dzcpvlw" ]
[ "Yep, every living language experiences change, and if you look at writings from a thousand years ago in French, German, etc. you'd have a very hard time reading them even if you understood Modern French or German very well. Different grammar rules, different words, and a lack of standardized spellings meant that languages changed quite a bit as writing became more commonplace \\(and therefore more standardized\\) and each language borrowed from its neighbors or got conquered by its neighbors! And as a fun fact, the biggest change to English actually came with the French/Latin influence from the Norman invasion of 1066, which we call the dividing line between Old English and Middle English." ]
[ 4 ]
[ [] ]
[ "url" ]
[ "url" ]
bakfsm
Why is it that in many languages (for example Germanic ones, like English or German) have their "noble" words, and almost exclusively the noble words, derived from Latin, whereas the common words are from the original (Germanic, in this case) language family?
EDIT: Yes, in English there are also many latin origin words in the common tongue, but English is also often called the "dirty bastard" of Germanic languages, meaning that it is also heavily influenced from Romance languages
Culture
explainlikeimfive
[ "ekc59kx", "ekcwgsv" ]
[ "Back in the day, like today, not everyone was equally educated. The most educated members of society got to learn more than just simple, everyday language. (German, English etc.) The Catholic Church performed their rituals in Latin. The clergy and the nobles were some of the best educated people in the land, so they got to learn Latin. They would speak to each other using little bits here and there from all of the languages that they knew, including Latin. This kept going long enough that everyone, even the less-educated, picked up on the changes. Even though everyone would use the mixed language, they still knew that the Latin sounding words were associated nobles and other highly educated people." ]
[ 7 ]
[ [], [] ]
[ "url" ]
[ "url" ]
bbv3xf
What is the nature of the laws of physics? Are they independent from everything and always are the same? Or are they dependent on matter?
Physics
explainlikeimfive
[ "eklpgln" ]
[ "The laws appear to be dependent on the structure of the Universe, particularly the quantum fields that spread across spacetime. Almost all the laws work equally well for matter and anti-matter, if that's your second question. Without matter, it's hard to demonstrate properties like mass and charge, but the laws are still the same (except the number of particles you're measuring is zero and zero times many things isn't interesting)." ]
[ 5 ]
[ [] ]
[ "url" ]
[ "url" ]
6tq5hb
What is nuclear radiation, and how does it actually kill people?
Repost
explainlikeimfive
[ "dlmn3k9" ]
[ "The kind of radiation people worry about from nuclear technology and the like is called _ionizing_ radiation. That means that it has the ability to mess with molecules by stripping off electrons and changing their chemistry. Biological systems are very intricate, complicated \"machines\" that require chemistry to work correctly. Imagine taking a .22 rifle and shooting it through a circuit board of a computer. Will the computer still work afterwards? Maybe — but probably not. The radiation here acts like the .22 bullet. In most cases if it messes with a cell, it'll just break the cell and that will kill it. Cells die all the time, and have means of \"self-destructing,\" so losing a few cells is no big deal by itself. Lose too many at once — like billions and billions — and you start to suffer health consequences. Only _really_ radioactive sources can do this to you, but absorb enough radiation in the short term and whole systems of your body will shut down, injuring or even killing you in the short term (e.g., a week or so at most). There is also a small but real chance that any one of those radioactive particles will modify the cell's DNA (in the same way as before — by messing with its chemistry), and a small but real chance that the modification in question will make the cell turn cancerous. So even if the radiation you absorb doesn't hurt or kill you, it can raise your chances of cancer — there is a probability of one of your cells having become cancerous. Your base lifetime fatal cancer risk in the USA is about 20%. A dose of 1 Sievert — a pretty heavy amount (5 Sieverts is usually fatal) — increases your fatal cancer risk by about 1% (which is to say, in a population of people exposed to 1 Sv, you'd expect to see 1% more cancers than if they hadn't been exposed). Radiation can pose a contamination problem from two angles. The first is that some radiation poses a chance of making other things radioactive. So neutron radiation, for example, can \"induce\" radioactivity in non-radioactive substances. Aluminum, for example, can get very radioactive if exposed to neutron radiation. I don't think your hypothetical chicken is likely to be a radiation threat just because it was irradiated, though, but this is an issue with massive sources of neutrons (like nuclear reactors, nuclear weapons, or particle accelerators). The other angle is through contamination by radioactive products. In this case it is not the radiation itself that is the contaminant, but the fact that there is \"radioactive dust\" that is a contaminant. So when a nuclear weapon explodes, it creates lots of tiny radioactive particles called fission products that then go up into the mushroom cloud. These can attach to dust or water molecules and then fall back to Earth. These fission products are versions of \"normal\" atoms, like iodine, that are somewhat broken. So regular iodine (Iodine-127) is good for you and so your body takes iodine that it finds (e.g., that you eat) and moves it into places in your body where it can do some good (like your thyroid gland). Great. But nuclear reactors and nuclear explosions create radioactive iodine (Iodine-131), which is chemically identical to the \"good\" iodine but will emit radiation. Your body can't tell which is which (because it uses chemistry to tell the difference), and so it takes the \"bad\" iodine (Iodine-131) and puts it in your thyroid gland as well. Once its there, it will decay away, releasing radiation, and exposing your thyroid gland to it, increasing your chance of thyroid cancer. So in your chicken example, if your chicken is contaminated by radioactive byproducts — e.g., that it ate or drank or breathed — and then you eat the chicken, now you've got those same byproducts in your body. Depending on the byproduct, it might just be excreted after some amount of time (your body can't do much with, say, uranium) but others might be either something your body like (like iodine) or chemically similar to things it likes (strontium is similar to calcium, and your body likes calcium) that your body will take these \"broken,\" unstable atoms and move them into places where they shouldn't be (like your thyroid gland, your bones, etc.). Animals are affected by radiation as well (as are plants!), though the damage can vary by species (insects, including but not limited to cockroaches, are famously more immune to radioactivity than mammals). For long-term cancer risks, some animals lack the lifespan to really suffer from cancer visibly (the cancers can take decades to develop, and if your species' lifespan is only 5-10 years, you probably won't see radiation-induced cancers), so it doesn't always pose the same threat to them as it does to humans (who live relatively long lives compared to most animals). At high-enough dosages of radiation, practically any living thing will suffer — with high-enough radiation you can even kill trees (it's been done experimentally)." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
8vldjs
I have bad misophonia, why does imitating sounds that upset me reduce the discomfort?
I have bad misophonia. Certain sounds, especially eating and 'non harmonious' sounds, like two TV's playing at once, cause me to feel very distressed, almost to the point of a panic attack. But I've noticed that if I imitate the sound which is bothering me I feel a lot better. Why? Also bonus question... what the heck actually causes misophonia?
Biology
explainlikeimfive
[ "e1oauc8" ]
[ "I suffer from this as well. It makes life extremely tedious. I've never heard that about imitating the sound. I'm going to try that and save this post to see if anyone provides any insight." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
5mnx2b
How does a digital timetable display know how far away a train is?
I commute via train for work; for the operator on the line, once a service is under 10 minutes out from a station, the automated display on the platform will change from simply stating, for example, 0822 in the "expected" section, to "9 mins", and updates every minute after that until the train arrives. I have noticed many times now that about 10 or 15 seconds after updating from "*x* mins" to "*y* mins", the time might jump back up, and then sometimes change again just as quickly - either up or down. I figure the need for the change is because of variations in passenger numbers at stations on different days (the particular stop I travel from is frequently almost empty on very cold/wet days as the platforms have little shelter), but where/how does the automated display get its info to update accordingly, and so quickly? Something from the driver, or the preceding stop/s? ^*Magic?*
Other
explainlikeimfive
[ "dc52bsm" ]
[ "This might depend on the city/country, but in Germany works like this: There is a antenna in the front of the tram or bus (which you might be able to see) which sends a signal on a specific wavelength which includes the tram/bus number (the number of the vehicle, not the line) and the current time as information. All over the city there are antennas catching signals of that specific wavelength. It reads which line the signal came from and also looks at the time the signal was sent and it's own current time. From that difference it calculates how much time passed since the signal was sent and since the speed of the signal is constant, it can calculate the distance the vehicle is away from that station. Now the station can't know where the train is tho, as there are many points that are that certain distance away from the antenna. To be exact, it can only say that the vehicle is on a cirle with the calculated distance as radius away from the antenna itself. So what it does is, it sends the distance it calculated and line it received to some kind of traffic center (idk how exactly you call that in English, hope you know what I mean). The center collects data from different antennas. With two antennas it can already reduce the number of possible positions to 2 (the intersections of both circles around the antenna). A third antenna is usually enough to find the exact location (just make sure the antennas don't lie on one line). I'd expect them to use more signals tho, to make sure there are no errors etc. Now that the position of the vehicle is known, the rest just works like a navigation system. The center then sends the info to the stations and trams/busses which approach that station. So now for why it changes, I must admit, I can't answer with certainty. I could imagine two possibilities: * The signals are a bit unprecise (the time calculation and therefore the distance calculation), so even if the vehicle is standing still, the center might recieve the info it's moving a bit. If it is standing at a red light and right at the \"border\" for needing 8 and 9 minutes to the destination, that might cause that change. * The navigation part is calculated dynamically, meaning the calculated time needed from one point to another varies, depnding on how much fast the vehicle is moving in general. When it recognizes the vehicle is moving normally it might display 8 minutes needed to your station, but if it suddenly becomes very slow, the center might recognize that and expect the vehicle to continue to drive slower, therefore needing a bit more time to your station. Btw in the second case an advanced algorithm should be able to recognize whether the vehicle just had one station where it lost a lot of time (= no negative impact on the time from point A to B) or whether it's constantly moving slower than expected (= more time needed from point A to B) ." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
8a3krs
Why are flies able to evade being swatted so easily?
Biology
explainlikeimfive
[ "dwvjulf" ]
[ "The do not avoid the swat, the swat pushes them away. Like a wave. It is from the lack of air going through your hand." ]
[ 5 ]
[ [] ]
[ "url" ]
[ "url" ]
5q1aeb
What does the EPA freeze actually affect?
I'm aware it freezes funding, but does that include currently ongoing research? Also, why can the EPA not even utilize their twitter account? Is this considered censorship?
Other
explainlikeimfive
[ "dcvjfmo", "dcw2uao" ]
[ "Yes, it includes currently ongoing research. Current employees are still getting their paycheck, but at the moment new expenses of basically any kind are getting denied. That means registering for conferences, traveling to field sites, updating software licenses, buying reagents, lab supplies, office supplies, instruments, and on and on and on. If the funds are already allocated, those purchases will *probably* go through, but nothing new until further notice, with no indication whatsoever on what the larger plan is, or for how long the current state is intended to last. The language covers grants and contracts, and if you know anything about how being a federal employee works, you know that *everything* you buy has to go through a pile of red tape and be under an official contract. The actual memo sent from the transition team to EPA upper management was somewhat vague in parts, and I fully expect individual branch offices to disregard it here and there where they think they can get away with it, but by and large it's affecting everything. Source: several (furious and depressed) friends who work at an EPA research branch. For example, one is a new postdoc who literally hasn't been able to do his job since Monday afternoon because he needs to resupply on trivial stuff like petri dishes but can't." ]
[ 40 ]
[ [], [] ]
[ "url" ]
[ "url" ]
a6t9pz
How do stores who sell gift cards for restaurants or other stores make a profit?
Economics
explainlikeimfive
[ "ebxr04y", "ebxtd9d" ]
[ "Companies sell their cards for less than face value. If you pay $25 for a card, the whole sale cost of the card is around $20." ]
[ 8 ]
[ [], [] ]
[ "url" ]
[ "url" ]
7aw2yt
In movies/TV where people are shooting guns, how do they make them look real?
Like, what's fake about it? Are they real guns with fake bullets? Is the actor pretending there's kickback with a prop gun that doesn't do anything and then effects are added later?
Other
explainlikeimfive
[ "dpdafyx" ]
[ "Some are real guns firing blanks, some are blank-firing prop guns, some are props that use a flammable gas to produce a flash and recoil, some are inert props and they just fake the recoil and add effects later." ]
[ 8 ]
[ [] ]
[ "url" ]
[ "url" ]
6enksv
why can restaurants take tip money out of their employees paycheck? A friend of mine works hospitality for a restaurant and makes hourly. She still makes tips. They told me that the tips they make affect their paycheck. How does that work?
Other
explainlikeimfive
[ "dibl0mo" ]
[ "Tipped workers are allowed to be paid under minimum wage for their hourly rate. Let's say minimum wage is $10. The job can pay $5 plus tips. HOWEVER, if you don't make enough in tips to equal minimum wage, the company is required to still give you at least minimum wage. If I work a slow lunch hour and only make $2 in tips, then the company must pay me $8 for the hour I worked, not the agreed upon $5. This means I am guaranteed minimum wage at least. And if I make enough tips I'll still get paid an hourly wage on top of those tips. In reality wait staff almost ALWAYS make well above the minimum wage requirements due to tips, so you're pretty much always getting that $5 hourly rate plus a big heaping pile of tip cash. This is why most wait staff prefer to work for tips instead of having a higher but stable hourly rate." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
9ujoed
how do caffeine and other stimulants work?
Biology
explainlikeimfive
[ "e94sk2t" ]
[ "Caffeine blocks the action of of the chemical adenosine which makes you feel drowsy. The caffeine molecule is similar enough to adenosine to temporarily block it's receptors in your brain. But caffeine doesn't get rid of adenosine, it just blocks it from functioning. Which is when the caffeine wears off you suddenly feel really tried." ]
[ 9 ]
[ [] ]
[ "url" ]
[ "url" ]
o8rjy9
Some insects and animals have the visibility range that includes IR and UV Rays. How can we imagine the visibility to look according to humans even though we can't see them?
Physics
explainlikeimfive
[ "h36rjo3", "h36wk6r", "h372fc9" ]
[ "Well it depends. We have only 3 types of cones, so we can't imagine what the world looks like for animals that can see more different colours. But more wavelengths don't require more different colours. If each cone had a wider \"bandwidth\" of wavelengths then we would just see everything we see right now as green, and some normally invisible colours as red or blue. The main difference in the world would be flowers. Many of them that are white to us are actually UV coloured and some even have UV patterns." ]
[ 10 ]
[ [], [], [] ]
[ "url" ]
[ "url" ]
ar7qjw
Why do traffic lights have a different hole for each coloured light rather than just putting them all in one?
Other
explainlikeimfive
[ "eglaxbg", "eglb15m", "eglcs1p" ]
[ "I was always told it was for people who are red-green colorblind who otherwise couldn’t tell what color it is." ]
[ 17 ]
[ [], [], [] ]
[ "url" ]
[ "url" ]
hhbqw5
Born with deafblindness
I've been wondering for several months how people who are born deaf and blind (by that I mean that they have never heard or saw in their lives and not that they lost either hearing or seeing gradually) communicate. I tried to google it but everybody is always talking about learning the alphabet quickly before they lose sight or so but no one ever speaks about people who are born without sight or hearing. To reformulate my question: How do people born with complete deafness and blindess learn to communicate?
Biology
explainlikeimfive
[ "fw9zr0i" ]
[ "Generally, you teach them blind sign language, so they sign and you sign into their hand to reply. It’s mostly similar to teaching a deaf child to sign, except that you have to have them touch things instead of just showing them a picture." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
nxwwy1
In some US States, video recording is legal but audio recording requires 2 party consent. Why are they treated differently?
Technology
explainlikeimfive
[ "h1hjnok" ]
[ "Most of these laws were actually written in regards to wiretapping, as in bugging a phone. Before surveillance cameras or even video cameras ever existed." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
6e2rai
Why are there different levels of sunscreen? Wouldn't someone want to use the highest level that is most effective against sunburns?
Other
explainlikeimfive
[ "di79apn", "di794yf" ]
[ "Because SPF 100 sounds way more awesome than SPF 15 and people might pay more money for it. The difference between sunscreens above SPF 50 is basically negligible. SPF 15 blocks about 93% of the harmful UV features from the sun. SPF 30 about 97% and SPF 50 blocks 99%. Any higher and you're just adding fractions of a percent of additional protection. So yes, higher levels of sunscreen are \"more effective\", but are you more likely to get a sunburn with SPF 50 than SPF 100? Not really." ]
[ 12 ]
[ [], [ "http://www.ewg.org/sunscreen/report/whats-wrong-with-high-spf/" ] ]
[ "url" ]
[ "url" ]
ccfthv
If Ethernet cable can transfer so much data, why not use this instead of HDMI and other cables for data.
In physics class I remember using Ethernet cables to connect two “gates” used to measure speed for objects. I also know that Line 6 guitars use an Ethernet cable to connect your guitar to your guitar processor. We also use an Ethernet cable to power our LAN phones at work. So why is the Ethernet cable not the master cable of electronics?
Technology
explainlikeimfive
[ "etmlu8k", "etn5as8", "etmxnyw", "etmx8w5", "etn5boy" ]
[ "> So why is the Ethernet cable not the master cable of electronics? You actually hit an idea that has been getting traction off and on for a decade or so. Basically, you CAN use Ethernet for all sorts of other purposes, including replacing an HDMI cable. Ethernet (twisted pair) could replace a whole bevy of different cables. Twisted pair wires work really well for a lot of stuff, they are cheap, and durable, and go long distances. It's a pretty good option. The problem... well, it just doesn't work as good for certain special things like a specialized cable like HDMI does for video. HDMI is purposely built to deliver very high bandwidth uncompressed video, to achieve the same with Ethernet, you'd need a pretty robust system, heavy shielding, and likely more than one connection (i.e. two Ethernet cables). Side note: HDMI actually can transport data as well (much like Ethernet), but there has been basically zero consumer implementation of this in devices. But could we replace a lot of \"generic\" cables with twisted pair (ethernet)? Yeah, we probably could, but there really hasn't been much interest to do so, and that the [RJ-45 jack]( URL_0 ) is fairly large, makes it quite impractical for smaller devices, especially ones that may need several ports." ]
[ 29 ]
[ [ "https://imgur.com/D4AO7BW" ], [], [], [], [] ]
[ "url" ]
[ "url" ]
dywuce
Why are broken escalators so difficult to walk up?
Engineering
explainlikeimfive
[ "f83yo3w" ]
[ "Their depth (front to back) and height (height to the next step) are both bigger than is standard for stairs." ]
[ 4 ]
[ [] ]
[ "url" ]
[ "url" ]
do2z0p
what shape is our vision?
Other
explainlikeimfive
[ "f5jjmou" ]
[ "Well our range of vision is limited by where our eye sockets block light from entering the pupil, so the shape of your eye socket (circle or a bit of an oval)" ]
[ 4 ]
[ [] ]
[ "url" ]
[ "url" ]
k4emqn
how do auditory tricks like the “green needle” “brainstorm” thing work?
I’m amazed that whatever word I’m thinking of or reading is the one that I here in videos like this URL_0 I can hear both but not at the same time and each time it sounds COMPLETELY different!
Other
explainlikeimfive
[ "ge8fe84" ]
[ "Haha, kind of like \"Yanny vs. Laurel\". & #x200B; It all comes down to your brain and what frequencies it can distinguish. Depending on which frequencies it filters out as more important than others, it'll perceive one word or the other. & #x200B; This is why hearing a video like this on one device versus another device may change what you hear. For example, if you listen to the video on a good system with low frequencies you may hear \"Brainstorm\", whereas listening to the video on a phone with the lows cut out may lead to you hearing \"Green Needle\". It also depends on other factors, like what word you're predisposed to hearing based on your past experiences!" ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
9y1fjg
How is setting a colony on another planet more favorable than staying on Earth?
Many people have suggested colonies on different bodies in our solar system as a means for establishing a new world when Earth runs its course. Still, how is any alternative better? Even Earth at its worst will require similar maintenance to preserve life as Mars or as the Moon. I don't see the advantage in leaving a poisonous, stark planet for another.
Biology
explainlikeimfive
[ "e9x99xt", "e9xaodi" ]
[ "Lots of reasons. Imagine there's a giant meteor hurtling towards earth while russia and america decide to whip their dicks out an play the \"My nukes are bigger\" game, north korea developes the zombie virus and bob from down the road has a dog that always shits on your grass EVERY FUCKING DAY. What do you do when you don't want to live on this planet any more (or it's about to become a lifeless rock)? You go to your summer home on Mars. Having more colonies is always a good thing. The further the better. Plus it's really cool." ]
[ 9 ]
[ [], [] ]
[ "url" ]
[ "url" ]
6000es
Why goverments just don't take fingerprints when issuing IDs?
I mean it's logical. You can catch criminals quickly and it's easy identification so no Joe Does
Other
explainlikeimfive
[ "df2edxx", "df2fsqq" ]
[ "Why not a DNA sample as well? A few hair follicles? Blood sample? The crux of the issue is your 4th amendment and right to privacy. There is no logical reason that you should have to provide any of this to be allowed to utilize public roadways and therefore it is a violation of your rights to collect this information without cause or warrant" ]
[ 16 ]
[ [], [] ]
[ "url" ]
[ "url" ]
m1ayk6
What does Francis Bacon mean by his 4 idols (tribe, cave, marketplace, theater)?
Other
explainlikeimfive
[ "gqcqw7j" ]
[ "The idols of the Tribe is the tendency to treat human perception too highly- humans perceive a distorted view of the world. The idols of the Cave is the specifically individual tendency to treat our own truths as objective truths, forgetting that we're manipulated by our own experiences and biases, just like everything else. The Idol of the Marketplace is the misuse or twisting of words. Specifically, saying things which are technically correct but misrepresentative of reality. Bacon considered this the most dangerous and would have absolutely hated Reddit. The Idols of the Theatre is believing in systems of religion or philosophy that obscure or twist reality. Basically that people tended to look for evidence that supported their worldview, rather than altering their worldview based on new evidence." ]
[ 6231 ]
[ [] ]
[ "url" ]
[ "url" ]
7t2vsg
Why is it that animals don't get acne and humans do?
Biology
explainlikeimfive
[ "dt9hljm", "dt9fn1m", "dt9jjpu" ]
[ "Animals totally get acne. It's slightly different from human acne, but it's acne nonetheless. In fact, [one of our cats has bouts of acne]( URL_0 ) from time to time." ]
[ 10 ]
[ [ "https://www.thespruce.com/feline-chin-acne-possible-causes-signs-treatment-3384889" ], [], [] ]
[ "url" ]
[ "url" ]
kjwhy5
why is glass transparent but other things are not? As in, why can you see through glass but not say a wall?
Physics
explainlikeimfive
[ "ggz8ako" ]
[ "Light is not reduced to the light we, humans, can see. As a matter of fact X-rays, Ultraviolet, Infrared, Microwaves, Radio waves, Wifi are all different types of light and Visible light is just a portion of the whole spectrum. Transparency is not reduced to visible light. Your cells are transparent to X-rays but not your skeleton and that's how doctors can examine your bones. Walls are transparent to radio waves and wifi so that's why you can listen to radio without needing an antenna outside your home and connect to the wifi from any room of your house. It happens that glass is transparent to visible light so we can see through. Now, the reason why glass is transparent to visible light and walls are transparent to radio waves has to do with their atomic structure. It is kind of complicated for an Eli5 but it is a matter of interaction between atoms and light: if the atoms interact with a specific kind of light, it can't get through unscathed so it is not transparent to that particular kind of light. If there is no interaction then the light just goes through and the result is transparency." ]
[ 18 ]
[ [] ]
[ "url" ]
[ "url" ]
k3wb71
How often can skincells renew themselves? (Retinol)
So, recently, I’ve been trying to take better care of my skin. I read about retinol A LOT. It’s supposed to speed up cell turnover. But cells do have a limited number of turnovers, no? I am afraid of using retinol, I am worried it might make my skin look nice for now but might ruin it in the long run (because of the quick cell turnover). Can someone please explain this? Where am I wrong?
Biology
explainlikeimfive
[ "ge5k3bl", "ge6ftnv", "ge5vkm4", "ge6d2cu" ]
[ "One thing you need to be careful with is taking retinol (Vitamin A) when you don't really need it. It's a fat-soluble vitamin which means it can build up in your tissues when you take too much. Water-soluble vitamins, on the other hand, can be freely removed by peeing them out if you take too much. Excess Vitamin A has also been linked to osteoporosis down the road, even if you're not taking dangerously high amounts." ]
[ 22 ]
[ [], [ "https://www.reddit.com/r/SkincareAddiction/comments/b8lna9/antiaging_dermatologist_criticises_longterm/", "www.reddit.com" ], [], [ "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2699641/" ] ]
[ "url" ]
[ "url" ]
aihrvx
If friction causes heat, why does moving air create a cooling sensation against skin?
Physics
explainlikeimfive
[ "eenv7i2" ]
[ "Normal wind doesn't move fast enough to cause significant skin friction. The cooling sensation is caused by something called convection. Basically, since air doesn't conduct heat very well, the heat from your body stays in the air pretty close to your body, and the best way to carry the heat from your body is to take the warmer air near your body away, and replace it with cooler air, which is what wind does." ]
[ 7 ]
[ [] ]
[ "url" ]
[ "url" ]
92t05j
What gives milk its white colour?
Chemistry
explainlikeimfive
[ "e3867b0", "e39bdec" ]
[ "The white stuff it contains: * [Butterfat]( URL_0 ), which is a bright yellow color * [Lactose]( URL_1 ) (sugar), which is white. * Proteins, mainly [casein]( URL_2 ) which is rich in calcium." ]
[ 5 ]
[ [ "https://en.wikipedia.org/wiki/Butterfat", "https://en.wikipedia.org/wiki/Lactose", "https://en.wikipedia.org/wiki/Casein" ], [ "http://www.chemistryexplained.com/images/chfa_01_img0212.jpg", "http://www.chemistryexplained.com/images/chfa\\_01\\_img0212.jpg" ] ]
[ "url" ]
[ "url" ]
l1qyrc
Why do impact drivers work better for installing and removing screws and bolts?what does the extra vibration do to help while rotating?
Engineering
explainlikeimfive
[ "gk13rpv", "gk14s6k", "gk14ln2", "gk13niu" ]
[ "It does a couple of things. First, the vibration isn't just vibration. The impact driver exerts very high torque on each impact, but it is much easier to control because it is broken up. If you were to apply the same static force, like from a drill, you would need much better leverage and risk shearing the screw. The second thing that happens is actually due to vibration. When a bolt is stuck, like a lug nut on a car, the vibration helps break corrosion or even cold welding on the nut/bolt. Drill's were never really meant to install screws and bolts, they work best when drilling holes. Impact drivers work great for removing/installing nuts, bolts, screws, etc... Screw guns work better than impact drivers for screws in wood and drywall, but are pretty useless outside of that. There are probably other principals at work, but those would be the main two." ]
[ 17 ]
[ [], [ "https://www.protoolreviews.com/news/how-an-impact-driver-works-training-the-apprentice/34862/#:~:text=An%20impact%20driver%20senses%20when,the%20hammer%20against%20the%20anvil" ], [], [] ]
[ "url" ]
[ "url" ]
eyx1g7
How do antibodies actually work? Does your body store antibodies for literally every disease it contracts during your lifetime, or is it more like a recipe?
Biology
explainlikeimfive
[ "fgjxj6u" ]
[ "So I answered a similar question a while ago. I'll paste and tailor it to your question. You want to defend yourself from the unknown. You don't know what's going to attack you, you just want to make sure anything that isn't you, that is inside you, gets destroyed. How do you go about doing that? Well put simply, the body takes a very intriguing approach to this difficult problem. It has some genes that code for proteins. It takes these genes and shuffles them around so they now create different proteins. Then you take these proteins and put them on the surface of some immune cells. These proteins now function as sensors. You wire these sensors in these immune cells such that when they're activated, the cell goes haywire, sending signals to the rest of the immune army and fighting one on one with what activated the sensor. These proteins have different sequences, and so they fold differently as the constituent parts of it interact with each other in a different way. If a protein is shaped a specific way and has a particular sequence, it can have affinity to certain other compounds or proteins. So that's how they \"sense.\" Of course, with this random approach, some of these sensors are bound to get activated when they come in contact with your own proteins and cells and so on. So the body first takes these cells through some \"schooling.\" It puts these immature cells in a specific place and exposes them to the different proteins and lipids and stuff that you have in your own body. If they react, that's bad, so they get killed. After this schooling, only cells that are unreactive to your body get to graduate and become mature cells that are allowed to patrol your body. When a foreign object or pathogen are in your body, some of these sensors may get activated due to chance. So the cells in which they are Release a bunch of signals. These signals bring in other cells that cause an inflammatory response. Which essentially activates a bunch more cells, dilates your blood vessels so more blood can come to \"fight\", makes your vessels more leaky so these soldiers can pass through and get to the tissue to fight, and so on. Part of this response is also that whatever cell got activated now gets all the attention, it starts to turn into a plasma cell and a memory cell. The plasma cell produces a lot of these antibodies that are known to work, so they help the immune system find more of that pathogen if it replicated. The memory cell just go and hides in your lymph for later, in case the pathogen infects you again. I extremely oversimplified the matter. It is far far more complex. Because there are also things called PAMPs, these are Pathogen Associated Molecular Patterns, basically things found in many pathogens. And our body evolved to have sensors for those. So those are sort of like a recipe. But pathogens also evolve like we do and they change to avoid these sensors. And there are sooo many types of immune cells with different functions, like some even bind to proteins on your own cells, and your own cells costantly sample their insides and break them into pieces and put those pieces on those proteins on the outside. And if an immune cell senses self on these proteins, you're good, and the cell is allowed to live. If it has foreign pieces on it, it gets killed. Like when a virus hijacks your cell. Some viruses even evolved to reduce these proteins on your cells so the sentinel cells going around don't detect them. Well we evolved too and if the immune cell detects that the protein is too low, they kill the cell too. Just to give you an idea about just how complex the immune system is. Edit: Woah the comment I copied also got gold, awesome! Thank you for the shiny stuff anonymous benefactor" ]
[ 18 ]
[ [] ]
[ "url" ]
[ "url" ]
f7dcxt
Where do the couple of lbs of weight go overnight while sleeping?
Biology
explainlikeimfive
[ "fian67v" ]
[ "You breathe out more than you beath in. The oxygen you breath in comes out as carbon dioxide or water, gaining carbon and hydrogen from the sugars your body burns. You breathe out water from saliva, mucous, and other sources of moisture within your mouth, nose, throat, and lungs. You also sweat and drool. It only takes about 170 mg per breath to lose a kg over eight hours." ]
[ 6 ]
[ [] ]
[ "url" ]
[ "url" ]
b4nbmd
How can a computer restart itself?
I am assuming a restart is the same as a shutdown and boot up. If that’s the case, how can a computer go from completely off, to turning itself back on without additional user input?
Technology
explainlikeimfive
[ "ej7u68p" ]
[ "When you shut the computer down, the operating system is shut down and the motherboard turns off afterwards. When you select restart, it shuts down the operating system but the motherboard stays on and boots the operating system again." ]
[ 12 ]
[ [] ]
[ "url" ]
[ "url" ]
afna33
How does geography affect the shapes of noses around the world?
Biology
explainlikeimfive
[ "ee050jt" ]
[ "I have read that the colder and drier the air, the longer, taller, and more narrow the nose. Narrow nostrils warm the air, and a longer 'tunnel' to go through also helps warm and moisturize the air you take in. I have a short button nose with rounded nostrils, and I actively avoid deep nose inhalations outside in the winter. It is like an ice blast to the sinuses/brain." ]
[ 8 ]
[ [] ]
[ "url" ]
[ "url" ]
jew0wa
Why do our eyes track something smoothly while when we look around ourselves they move on a constant interpolation?
I always wonder how we do it. When we track (for example) a ball, our eyes roll smoothly, tracking it with no constant movement but when we look around in our place, our eyes instantly "switch"?
Biology
explainlikeimfive
[ "g9gy682" ]
[ "The smooth tracking that you described is called \"smooth pursuit.\" In some cases when your eyes are tracking an object, such as a rolling ball, your eyes follow the object smoothly without \"jumping.\" However, when the eye moves at speeds greater than approximately 30 degrees/second when tracking an object, it will actually begin jumping in the same manner which you described the eye jumping around a room. The faster our eye has to move to track that rolling ball, the more jumps we begin to make, although the tracking might seem smooth as you stated, the eye is actually moving in the same way as when we our eyes jump around and explore a room. I will attempt to explain why the minute jumps your eyes make when tracking a ball are smooth just like the progression of images you perceive when your eyes jump around a room. These jumps are called saccades. The eye is one of the fastest moving mechanisms of the human body, capable of moving up to 900 degrees/second. When we take in a room or environment the eyes moves in a rapid succession of saccades, focusing on one point and then jumping to another in fractions of a second. These jumps help us build a mental map of our surroundings. Now, if we were to actually \"see\" when our eye makes these high speed movements, we'd probably get terribly sick and dizzy. When taking in a room, you'd just see a series of blurred movements interspersed with a still image lasting a fraction of a second. Very rapid movements of the eye are masked so that the blurred image our eye sees is not passed to the brain. This process is called saccadic masking. Saccadic masking works by filling the missing visual input from the saccade with the new input from whatever new target your eye has jumped to. This process is called backdating, and results in a phenomenon known as chronostasis. This can be most readily observed when your eyes jump to look at a clock. You may notice the second hand on the clock seems to freeze for a fraction of a second before moving. Saccadic masking can backdate visual input by up to 500ms. The further your eyes travel during a saccade, the longer the amount of time that needs to be masked. TL;DR: Eye go zoom but brain no see when eye zoom, instead new picture lasts longer." ]
[ 14 ]
[ [] ]
[ "url" ]
[ "url" ]
86tdph
Who first discovered dinosaurs? And what was the original explanation behind the discovery?
Other
explainlikeimfive
[ "dw7o1kh", "dw7o5xi", "dw7pruq", "dw7o1j9", "dw7oi1m" ]
[ "William Buckland, 1824. But realistically a lot of mythological creatures, dragons for example, are probably early attempts to explain finding fossils. URL_0 If you're into this kind of stuff check out the bone wars. URL_1" ]
[ 8 ]
[ [ "www.scholastic.com/teachers/articles/teaching-content/when-was-first-dinosaur-discovered/", "https://en.m.wikipedia.org/wiki/Bone_Wars" ], [], [], [], [ "https://www.scholastic.com/teachers/articles/teaching-content/when-was-first-dinosaur-discovered/", "http://www.enchantedlearning.com/subjects/dinosaurs/dinofossils/First.shtml" ] ]
[ "url" ]
[ "url" ]
e0eyzk
How can some things be sold so cheap?
Specifically I just picked up a pack of cookies, 6.17 oz's caramel chocolate and from the Netherlands, so can you dumb down how they can manufacture, then ship from over seas and still make it worth selling for one dollar? It was at one of them el cheapo dollar places... well they sold other stuff too that wasn't just a dollar but, I just can't comprehend.
Economics
explainlikeimfive
[ "f8dldd4", "f8douh3" ]
[ "You will notice most of the ingredients would be sugar, something that is extremely cheap. Cost of manufacturing for most things is really miniscule nowadays as we are talking about a handful to a dozen workers overseeing a set of machinery that can produce thousands of these sweets a minute. As for shipping, if you are shipping in bulk via cargo ships, it is also extremely cheap. A single cargo ship can ferry thousands of containers per trip. Each container can hold tens of thousands of boxes of these sweets. Per box, these costs are really small." ]
[ 14 ]
[ [], [] ]
[ "url" ]
[ "url" ]
kupu5h
Why is a nose running in winter, even though you don't feel sick?
Biology
explainlikeimfive
[ "gitit61", "gitet8x" ]
[ "Lots of possible answers. The simplest could be that warm air coming out into a cold space produces moisture. Thus the feeling of a runny nose." ]
[ 6 ]
[ [], [] ]
[ "url" ]
[ "url" ]
cna1om
What are the gun laws in America? As in, what can you buy, when can you buy? I.e. which guns could you buy at what age and what guns are illegal to own?
Other
explainlikeimfive
[ "ew87fc2" ]
[ "At the federal level, you need to be 18 to purchase a rifle or shotgun and 21 to purchase a handgun. Some states have implemented or begun to implement a ban on selling AR rifles and their variants to anyone under the age of 21. There are a ton of guns which are illegal to own in various places and the list is too large to include in this post. As a general rule, states tend to impose their own bans on specific models of firearms. There are special federal tax stamps which allow you to own certain types of weapons, such as Short-barreled rifles and shotguns, as well as fully automatic weapons (as long as they are pre-ban models), suppressors, etc. These are manually reviewed on a case-by-case basis and require a lot of paperwork and a small amount of money, typically around $250-500." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
afwg1g
What is shift factor and load when referring to generators
Engineering
explainlikeimfive
[ "ee1s5me" ]
[ "Shift Factor is a pretty obscure electrical power term. When a change in generator output occurs, the change in current measured at the junction to the power grid, called the flowgate, isn't exactly the same. It's a function of transmission dynamics and distances. Shift factor is the ratio of flowgate change to generator change. Load is generally the amount of power needed to operate the device powered by the generator, though there are more esoteric definitions for obscure cases." ]
[ 4 ]
[ [] ]
[ "url" ]
[ "url" ]
dy7zxy
How did people get enough food in pre-historic times
I know that we've cultivated fruits, veg and berries to grow bigger and more nutritious over time, but how did people survive with so much more exertion and less beneficial foods.
Biology
explainlikeimfive
[ "f7z4ttz", "f7z6tsg", "f7z516v" ]
[ "Until 12,000 years ago, essentially all humans got their food in the wild from hunting, gathering, and fishing." ]
[ 23 ]
[ [], [], [] ]
[ "url" ]
[ "url" ]
gmt0ml
- From a business standpoint, what is the goal of big companies giving their CEOs big bonuses when there's an economic crisis?
Economics
explainlikeimfive
[ "fr5izi2" ]
[ "It is to keep them from leaving. When businesses are going through an operational crisis, they need good management to keep them afloat." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
azwdck
How come so many species of animals have a 1:1 ratio between male and female?
Biology
explainlikeimfive
[ "eiai1zu" ]
[ "[Fisher's principle]( URL_0 ). > - Suppose male births are less common than female. > - A newborn male then has better mating prospects than a newborn female, and therefore can expect to have more offspring. > - Therefore parents genetically disposed to produce males tend to have more than average numbers of grandchildren born to them. > - Therefore the genes for male-producing tendencies spread, and male births become more common. > - As the 1:1 sex ratio is approached, the advantage associated with producing males dies away. > - The same reasoning holds if females are substituted for males throughout. Therefore 1:1 is the equilibrium ratio." ]
[ 23 ]
[ [ "https://en.wikipedia.org/wiki/Fisher%27s_principle" ] ]
[ "url" ]
[ "url" ]
cxekkr
Do trees produce oxygen or not?
Biology
explainlikeimfive
[ "eyklvrp", "eykl8yq", "eyknaee", "eykzjfl" ]
[ "Trees produce oxygen. No doubt about that. But the same amount of oxygen is bound back up when the trees are burned, rots or eaten in other ways. So in that sense they are carbon neutral. But wait, there is more. * First, not all tree products are consumed but remains as litter, structures, etc. So we do end up with a decent oxygen surplus and carbon removed from the atmosphere. * Second, a forest is more than trees. Even if we don't care about biodiversity, the forest keeps that soil litter from decomposing and eating up the old oxygen surplus while releasing all that trapped carbon into the atmosphere. It protects soil algae and epiphytes that also release oxygen and so on. * Third, a forest is more than the sum of it's parts. When a forest grows big, like the Amazon, it is not just a product of climate, it creates it. By retaining water in root systems and releasing it from moist soil and cell respiration, it cools the area through evaporative cooling and creates rain systems. So remove the Amazon and you are not left with well-watered plains but drying badlands. And the resulting changes in water circulation is felt globally. * And, oh yes, fourth, a lot of the things that happens as part of that tree carbon cycle also benefits us directly, giving us building materials, fodder, soil, meat etc etc. While at the same time being carbon neutral at worst, or giving an oxygen surplus and carbon dioxide reduction on the short to medium term. So, yeah, that's why a little knowledge is a dangerous thing, and speaking as a biologist few things scares me more than conservatives who have gotten hold of one factoid that suits them and think they know everything worth knowing." ]
[ 112 ]
[ [], [], [], [ "https://www.unece.org/forests/outlook/carbonsinks.html", "https://en.wikipedia.org/wiki/Organic_matter", "https://www.ipcc.ch/site/assets/uploads/2018/02/AR5_SYR_FINAL_SPM.pdf" ] ]
[ "url" ]
[ "url" ]
9d6wzr
sound of rain
Physics
explainlikeimfive
[ "e5fp65b" ]
[ "Impact spreads the kinetic energy of the droplet into the surface and surrounding air particles. When air particles vibrate, we call it \"sound waves\"." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
aju7tw
why/how is a 24 MP full frame camera sensor better than a 26 MP APS-C camera sensor
Technology
explainlikeimfive
[ "eeyut7t" ]
[ "A \"full frame\" sensor is the \"full\" size of a 35mm film frame while APS-C sensors are smaller, originally shrunk to make compact (film) cameras smaller. Given that the pixel count of the sensors are almost the same, the individual sensor elements (think of them as pixels) themselves have to be bigger in the full frame sensor. This means that you get more light per pixel and thus increased sensitivity (less noise or better performance in low light). There's no more distortion with cropped sensor cameras as /u/nokvok suggested; the lens projects a circular image on the back of the camera housing. If you put the same lens on a full frame and a cropped sensor camera, the smaller sensor simply sees a smaller portion (in the middle) of the projected image. In fact, you might see MORE distortion with the full frame camera because the edges of the projected image are usually where it shows up the most." ]
[ 4 ]
[ [] ]
[ "url" ]
[ "url" ]
5y7hai
Is animal milk healthy for adults? Or is it harmful?
Looking information about milk being healthy on internet is an absolute chaos, every article is different to each other, and while some will tell you about how good it is other will consider it absolutely pernicious. So, without join in ethical debates, could someone explain to me like if I'm five about the benefits or disadvantages about drinking animal milk?
Biology
explainlikeimfive
[ "densb6x", "denqxja", "denuicc" ]
[ "If you think a particular diet works for you, great, follow it. But science doesn't really support any of that crap... Mind the calories, get your vitamins, have a bunch of fiber and you're good to go. If you ate a bunch of fresh veges and got some protein, doesn't really matter where the rest of you calories come from. With milk there is an agenda either way, so googling is probs a nightmare... neither good nor bad, but is calorie heavy." ]
[ 15 ]
[ [], [], [ "http://evolution.berkeley.edu/evolibrary/news/070401_lactose" ] ]
[ "url" ]
[ "url" ]
5upnaj
why are airline crash victims described as souls typically when most other deaths are described as lives or people?
Other
explainlikeimfive
[ "ddvy7aw", "ddvwihh" ]
[ "souls meaning living persons. which is passengers and crew airliners carry corpses too and they're held as cargo, not passengers. when you have a crash and you end up with 100 bodies, you need to know how many actually died in the crash." ]
[ 11 ]
[ [], [] ]
[ "url" ]
[ "url" ]
6nhidx
Have we ever reached absolute zero? Why/Why not?
Physics
explainlikeimfive
[ "dk9hfxg" ]
[ "No Absolute Zero is just a theoretical concept think of temperature in terms of transfer of heat from hot to cold. When an object cools down, what it's really doing, is losing some of its heat until it is equal to the surrounding area. AZ is an asymptote, which means you can exponentially approach it, but will never reach it." ]
[ 13 ]
[ [] ]
[ "url" ]
[ "url" ]
gukiy7
Why is it that when your body is tingling from laughter it becomes difficult to exert any physical strength?
Biology
explainlikeimfive
[ "fsjfrdc", "fsjk7ze", "fsjlw07" ]
[ "Generally, laughter changes breathing patterns, lowers blood pressure, uses a lot of the brain, and releases feel good and relaxation chemicals. Your body goes into a state of happiness and relaxation, which is counter to exercise. If you have a hard laughter session, your body is pumped full of chemicals that need to clear out before you can do sustained physical exertion." ]
[ 116 ]
[ [], [], [] ]
[ "url" ]
[ "url" ]
5ld3ls
why does it hurt when you swallow a beverage "wrong" ?
Some people will say "oh it just went down the wrong tube..." what is the real reasoning behind this sharp pain?
Biology
explainlikeimfive
[ "dbuvik6", "dbux4no", "dbv0r1z", "dbux23t", "dbv47le", "dbuzxoa", "dbuw5cn", "dbvajgc", "dbv1vig", "dbv0pkq", "dbv020o" ]
[ "When you take too big a swallow, it stretches your esophagus, causing it to spasm. This hurts." ]
[ 1903 ]
[ [], [], [], [], [], [], [], [], [], [], [] ]
[ "url" ]
[ "url" ]
5w2hr3
What are boards (in companies), what do they do, what use are they, and what are their powers?
Other
explainlikeimfive
[ "de6u57q", "de6t58i" ]
[ "The C-level executives (CEO, CFO, COO, etc) of a company run it on a day-to-day basis. The board usually consists of the CEO as well as a number of people who aren't employees of the company (these are called outside directors). The outside directors get paid a lot less than the company's executives usually, but the time commitment is a lot less (a handful of meetings per year). They represent the company's shareholders and provide very high-level oversight and guidance. They can fire the CEO and generally provide input on major company decisions. The board also has some more specific functions, like determining the compensation of high-level executives, reviewing the company's SEC filings (if it's a public company), considering proposals by other companies to buy the company, and approving purchases of other companies." ]
[ 5 ]
[ [], [] ]
[ "url" ]
[ "url" ]
6rehex
How is it that amazon can deliver packages the same day it's ordered?
Other
explainlikeimfive
[ "dl4edtt", "dl4f8iu", "dl4fb2b", "dl4lvq2" ]
[ "They have warehouses where they store a lot of their prime items. Since most people live somewhat close to a major metro area there is a good chance they have what you need within a few hours. That would be my guess." ]
[ 9 ]
[ [], [], [], [] ]
[ "url" ]
[ "url" ]
i0asr3
The great reset.
Economics
explainlikeimfive
[ "fzocj5c" ]
[ "There is no real way to answer this, as it would be quite controversial as to what would actually happen. When they want however, is a world wide move away from capitalism and a world wide embrace of socialism. There are thousands of discussions about socialism vs capitalism already and you can simply consult those to get different point of views on how that might end up looking." ]
[ 10 ]
[ [] ]
[ "url" ]
[ "url" ]
a2es61
Is water never produced, only recycled?
I read recently that the total amount of water on earth is always constant. Not a drop more, not a drop less. Everyone on the internet says contradicting things. What do you guys think?
Chemistry
explainlikeimfive
[ "eaxjg1h", "eaxkfnz", "eaxkgri", "eaxmbqu" ]
[ "Water is produced by burning all forms of hydrocarbons and is used by plants to combine water and CO2 into sugar. You turn sugar back into water and CO2 when you eat and metabolize it." ]
[ 18 ]
[ [], [], [], [] ]
[ "url" ]
[ "url" ]
chf95o
If you're stranded in the middle of the ocean and start to feel dehydrated, why is just drinking the seawater​ around you bad? Why will it not hydrate you?
Other
explainlikeimfive
[ "eushmd7" ]
[ "Osmosis. Salt water has more salt in than the cells in your body and your blood. So instead if drinking salt water and the water being absorbed, it actually gets drawn out of cells towards the saltier water. You end up peeing out more than you drink because the kidneys can't concentrate the urine more than the salt water, instead water is drawn out into the urine so you lose water." ]
[ 8 ]
[ [] ]
[ "url" ]
[ "url" ]
alvsi6
"air quotes" (I really need anexplanation for my 5-year old daughter)
Culture
explainlikeimfive
[ "efher74", "efhcvsp", "efhd0bb" ]
[ "Welcome to my favorite part of other peoples' kids' childhoods: The age where they understand that jokes are funny, and understand the structure of certain jokes, but don't understand that you can't just plug in random words to that structure and suddenly make the joke funny. Does she also tell knock knock jokes that go something like: Knock-knock Who's there? Banana Banana who? Banana monkey ook ook ook! Because those are my favorite. Sorry, I got distracted. Anyway, air quotes are for when you say one thing, but you really mean the opposite. So if you say: Hey dad, that shirt looks \"awful\" then you're really telling dad that his shirt looks great. It's not a very nice thing to do when it goes the other way. (I'm not sure how to go any deeper into this subject without having to try to break down the concepts of irony and implication to a 5 year old, which I don't think I'm qualified to do)." ]
[ 20 ]
[ [], [], [] ]
[ "url" ]
[ "url" ]
9js1gr
does peeing more often condition our bodies to feel the need to pee more often without actually having a fuller bladder?
Biology
explainlikeimfive
[ "e6tujsk", "e6u03l9" ]
[ "Think if your bladder like a rubber band. It’s all about its ability to expand. Medications that decrease your need to pee do so by allowing the muscle surrounding your bladder to relax so the bladder can expand more. Additionally, the more you hold your bladder, the more it expands. Think of this aspect like the stomach of a competitive eater. The stomach is designed very similar to the bladder, many wrinkles that allow it to stretch to much larger than its resting size. Before a Competition they eat tons of salad to stretch their stomachs, afterwards the stomach shrinks back Down to a normal size, making them feel fuller faster. What I’m getting at is, the more you let your bladder fill and expand, the more it will stay expanded at rest, and the more volume it can contain before the nerves that make you feel like you have to pee are stimulated. Thus, to answer your question, if you’re peeing more often with less urine in your bladder, eventually it will decrease in size and you will feel like you have to Pee more often." ]
[ 309 ]
[ [], [] ]
[ "url" ]
[ "url" ]
irnkbl
Student loans
Other
explainlikeimfive
[ "g506vhq", "g50a7gl" ]
[ "Many people in the US bought into the idea that getting a college degree - any college degree - would mean they would have a good career, and that was simply never true. There are many degrees that simply are not very employable - a BA in History for example sounds very interesting, but what job can it help me get? It’s not enough to teach high school history without some additional certifications, all for a low paying job. This pattern repeats for many, many bachelor programs and even some at the Masters level. Combine this with easy to get student loans that now have 5% interest rates and people can’t dig themselves out." ]
[ 4 ]
[ [], [] ]
[ "url" ]
[ "url" ]
8kintb
Why do some things cut better with a serrated knife and others with a straight blade?
Physics
explainlikeimfive
[ "dz7ztsk", "dz83lcm" ]
[ "It actually depends on a few factors. What you are cutting, the type of knife or blade you are using, and other things like temperature of the knife and the object you are cutting. The biggest determiner, is the thing you are cutting. Soft, malleable things like loaves of bread, or very loose meat, don't cut well with a sharp edge because you don't have enough tension in the material you are cutting to press against the blade and create an even cutting surface. Tomatoes and Bread are excellent examples of this. Only the sharpest of sharp knives can even hope to cut cleanly and evenly through some breads and most tomatoes without issue or mushing. Serated blades, seek to change this by adding in the serrations, tips and points that act to tear and have sharp points that press into what you are cutting and pull small sections, like a saw blade and tear bits and pieces instead of cutting cleanly and straight through. Very, Very hard things also have the same problem, like bone or frozen foods. The ice makes the object to cut so hard and dense, that a sharp knife is almost useless. A serrated knife on the other hand, can cut by ripping and tearing its way through the object where a standard blade could never perform." ]
[ 266 ]
[ [], [] ]
[ "url" ]
[ "url" ]
jqxikq
what determines whether something can be changed by executive order vs requiring congress/senate to pass?
Other
explainlikeimfive
[ "gbpvp15", "gbpv5n2", "gbpu82m", "gbpz467" ]
[ "The Presidents main power lies in being the head of the executive branch in the US. He can command all the offices below him, but laws require congress to pass them, full stop. The specific way those laws are enforced is done via executive order." ]
[ 16 ]
[ [], [], [], [] ]
[ "url" ]
[ "url" ]
8phmk8
how can a tv remote sit around all day not wasting it’s batteries and immediately be picked up and used (without having to be turned on), while something like a game controller must be turned on first before use, and if you left it on all day it would drain the batteries even while not in use?
Technology
explainlikeimfive
[ "e0bbjzj", "e0bcrhu", "e0bg73e", "e0be846", "e0bflnp", "e0bhngl", "e0bwrcs", "e0bm1qn", "e0c3db8", "e0bmh3a", "e0bjuct", "e0bg0dk", "e0bkene" ]
[ "a tv remote is a usually one way communication and uses IR. the remote emits a signal when a button is pushed and the tv receives it. it's like using smoke signals. a game controller communicates through bluetooth which is active two way communication. just by keeping it on and idle, it'll consume power. and controllers can also do other things, such as transmit audio, rumble, etc." ]
[ 13518 ]
[ [], [], [], [], [], [], [], [], [], [], [], [], [] ]
[ "url" ]
[ "url" ]
879nwe
what’s the difference between all the different types of lightbulbs? Incandescent, fluorescent, LED, any others?
Technology
explainlikeimfive
[ "dwb7ldf", "dwbx8s3" ]
[ "Brief explanation: **incandescent**: *very* thin tungsten wire is heated by putting electrical current through it, this creates a lot of heat and some orange looking (\"warm\") light. Not very efficient as a light source, quite efficient as a space heater. The wire burns out after a while. **halogen lamp**: think incandescent bulb version 1.1: still has a thin tungsten wire, but the bulb is filled with special gasses that allow the wire to get hotter without burning out. This means a little bit more light for the same amount of energy, but still not very efficient. **flourescent light**: glass tube with electrodes at either end, the glass tube is coated with chemicals and filled with special gasses. Voltage is applied to the electrodes and through some tricks the gasses are heated to such a point where an electrical current flows through the gasses in the tube. The electrons then bumb into gas molecules which creates UV light, the UV light hits the coating of the tube that creates visible light. More efficient than the above, but still wastes energy as heat. Also contains at list a tiny amount of mercury for the \"startup trick\". **LED**: a tiny piece of special material called a semiconductor is created that creates light from electrons bumping into atoms (gross simplification). By choosing the right semiconductor material you can choose the color of light, for white light the most efficient way is to again create UV light which then is converted into visible light by some material (similar to an fluorescent tube, material is called *phosphorus*). Quite efficient, but still creates quite a lot of heat and unfortunately cannot deal well with getting hot - > we need some kind of cooling e.g. a metal heat sink." ]
[ 7 ]
[ [], [] ]
[ "url" ]
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7ibajc
Why is it that some roads have a disproportionate number of gas stations and fast food places on one side of the street instead of the other?
I notice this often on many streets in my city. It's kind of annoying when you're hungry or need gas.
Other
explainlikeimfive
[ "dqxi2zh", "dqxr72n" ]
[ "Could be zoning laws, the availability or lack of infrastructure such as water and sewage or electrical. Property owners refusing to build or allow businesses to be built on their property, legal restrictions...it could be any huge amount of reasons." ]
[ 8 ]
[ [], [] ]
[ "url" ]
[ "url" ]
i1nsov
Medically Induced Comas
Biology
explainlikeimfive
[ "fzyqdj9" ]
[ "I'm a critical care paramedic and routinely perform RSI (Rapid Sequence Intubation) as part of my scope of practice. As part of this procedure, we induce coma or unconsciousness with an initial high dose and then ongoing infusion of opioids (morphine or fentanyl) and a sedative of different drug classes (midazolam and ketamine) depending on the presenting reason for induction. The medications used can change depending on where in the world you practice medicine, but the ones listed above are used within my service. It is this ongoing infusion of medications that maintains the patients coma. We then paralyze our patients, preventing their own muscular contraction, and taking over maintenance of their ventilation and oxygenation with mechanical ventilators. This is a high risk procedure and is done only after strict and prolonged education and ongoing routine professional development. & #x200B; edits for simplification" ]
[ 7 ]
[ [] ]
[ "url" ]
[ "url" ]
g5hs54
how does game streaming servers handle games and users at once compared to personal computers?
Technology
explainlikeimfive
[ "fo3m5wh", "fo3dw3z" ]
[ "Having been a production server engineer for almost 10 years, I can tell you it primarily comes down to CPU and network. These days servers are most commonly are equipped with \\~24-core Xeon processors, and while probably not faster than your own personal computer's CPU on any one job, it can do a lot more jobs at the same time. To put into perspective, on a single server with that processor you could deploy 24 dual-core virtual machines while retaining nearly full CPU performance in every VM, even if they were all to use 100% of their available CPU at the same time. As far as network goes, servers are commonly equipped with a network interface capable of at least 10-25 Gigabits of bandwidth, and they will have multiple network interfaces. The datacenter they reside in will be providing at least thousands of Gigabits of bandwidth. You on the other hand, probably have at most a single 1 Gigabit network card on your system, and your internet provider likely can just barely get you 1 Gigabit of bandwidth." ]
[ 7 ]
[ [], [ "https://stadia.dev/static/images/about/about-data-center.jpg" ] ]
[ "url" ]
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hqddb2
- why does it take less energy to fling something out of the solar system than it does to toss it into the sun?
Assuming this is true. URL_0
Physics
explainlikeimfive
[ "fxx44ag", "fxx5j6t" ]
[ "To shoot something out of the solar system from Earth's orbit you need to get it to an orbital velocity of 42 km/s. To drop it into the sun you need to reduce the orbital velocity to nearly zero or it'll just pick up a new orbit around the sun. The Earth is already moving at 30 km/s so to kick something out of the solar system you only need to add 12 km/s, but to drop it into the sun you need to burn off 30 km/s, nearly 3x as much It's all because you're on Earth and have to factor in its starting speed" ]
[ 46 ]
[ [], [] ]
[ "url" ]
[ "url" ]
ksb6ew
What makes milk go bad outside of the fridge while a cow's body is warm?
Biology
explainlikeimfive
[ "giey228", "giezjfq", "gif50th", "giexzdk" ]
[ "Food goes \"bad\" because organisms from outside start to make it their home. This is how fridges and freezers work, by creating an environment that's difficult or nearly impossible (respectively) for these critters to take hold. & #x200B; Food, or in this case milk, doesn't go 'bad' inside the cows body because these organisms can't get to it there. There are \\*other\\* bad things that can get to it there, which is why we tend to pasteurise milk as part of the whole milking-bottling-getting-it-to-a-shop process - this involves applying high heat to it to kill off any critters inside. From this point on, though, it's only a matter of time before new critters get in from the outside. The colder it is, the less chance there is of this happening, thus we put it in the fridge." ]
[ 38 ]
[ [], [], [], [] ]
[ "url" ]
[ "url" ]
adfkh0
How is Betamax different from VHS?
Technology
explainlikeimfive
[ "edgm7am" ]
[ "Betamax had slightly better picture and sound. The main downside was that only Sony could make Betamax equipment so *everyone else in the industry* put their weight behind marketing VHS equipment, giving you more selection and lower prices. Lower prices won." ]
[ 5 ]
[ [] ]
[ "url" ]
[ "url" ]
6d8n95
why some people have to pee when they get really nervous, even though this opposes the "fight or flight" response?
Biology
explainlikeimfive
[ "di0ttgn" ]
[ "When you are in immediate, mortal danger, (say, you are being chased by a tiger) your body released a massive flood of adrenaline. It's this adrenaline which activates the fight or flight response. Evolution has designed fight or flight to maximize our chances of survival which, in the case of the tiger, means running as fast as possible. Carrying a full bladder of pee while running is a bad idea as it will make you slightly heavier, and so slightly slower. We void our bladder during fight or flight to make ourselves that little bit faster. Now, when you are nervous you also get a small adrenaline rush. Not as much as fight or flight levels, but a little. This adrenaline triggers the pee reflex, making you feel like you need go. Peeing out of nervousness doesn't oppose FoF, its more like a milder form of it. If you were being chased by a tiger you wouldn't feel like you need to go - you body would make you pee your pants long before you realized it was even happening." ]
[ 3 ]
[ [] ]
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b97sep
Why is it that when you breathe your chest/stomach area rises with the inhale and falls with the exhale, but when you intentionally take a deep breathe (inhale) you suck in your stomach rather than jutting it out?
Biology
explainlikeimfive
[ "ek2tnnp", "ek36zt1" ]
[ "To take the biggest breath you possibly can (known as a forced vital capacity breath), you have to contract the diaphragm and external intercostal muscles more forcefully. Doing this (in conjunction with other muscles used during forceful breathing) pulls the rib cage up and expands it outward and this prevents the outward abdominal movement you're referring to." ]
[ 6 ]
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