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lvk5c1
|
- what’s so bad about swearing?
|
Other
|
explainlikeimfive
|
{
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"text": [
"[Vsauce]( URL_0 ) has a great video on this subject. For many words, the \"badness\" is an important part of the meaning of the words which make them uniquely useful.",
"Its just cultural residue. They're bad because people say they are bad, you know the reactions they will cause so they feel illicit regardless of whether you believe there is a difference between \"rump\" \"butt\" or \"ass\". We're all just trying to get that soap taste out of our mouths.",
"If a swear word is used too frequently it becomes diluted and meaningless as a swear word. The more sparingly and extraordinarily it is used, the more powerful it is."
],
"score": [
5,
5,
4
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"text_urls": [
[
"https://www.youtube.com/watch?v=Dd7dQh8u4Hc"
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[],
[]
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|
[
"url"
] |
[
"url"
] |
|
lvmzim
|
What is a drycleaner? How exactly does a person clean clothes without getting them wet.
|
How does a person dry clean clothes?
|
Other
|
explainlikeimfive
|
{
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"text": [
"\"Dry\" is referring to not using **water**, not not using any liquid at all. It's just washing with non-water solvents, often tetracholorethylene or other halogenated solvents.",
"Clothes [do get wet when dry-cleaned]( URL_0 ). Dry-cleaning just uses a chemical bath rather than soapy water.",
"Dry cleaning use other solvents then water. These solvents is usually selected to be very efficient at removing stains but not interact with the fibers of the garments like water will. So they do not damage the fibers in the same way but are still able to clean the stains out.",
"They get wet, but not with water. Solvents, the classic was perchlorethylene, if I remember."
],
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14,
7,
4,
3
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"text_urls": [
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"https://en.wikipedia.org/wiki/Dry_cleaning"
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[]
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|
[
"url"
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[
"url"
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lvn13p
|
what causes you to get cold chills when your stomach hurts? (When your body temp is still normal, no fever)
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpdb1dg"
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"text": [
"I want to say it has to do with your stomach needing to work harder, so your body sends more blood that direction, meaning your \"ends\" (like arms and legs) have less blood and therefore feel colder, creating a chill."
],
"score": [
5
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"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
lvnnmo
|
Why does garlic sometimes turn blue after cooking?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gpct5qp"
],
"text": [
"The color change is caused by a reaction between enzymes and sulfur-containing amino acids in the garlic (the same enzymes are responsible for garlic's flavor). ... When these enzymes are activated by mild acid, they produce blue and green pigments."
],
"score": [
7
],
"text_urls": [
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|
[
"url"
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[
"url"
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|
lvnttm
|
Why can't you just program a robot to click the "I'm not a robot" sign?
|
Sorry for my bad english, i hope y'all can understand it. Have a nice day!
|
Technology
|
explainlikeimfive
|
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"text": [
"they totally can, i found a video on youtube where some robot did exactly this the part that is supposed to catch them is the capcha that follows",
"You can. And you'll be getting whether or not your not programming is better than Google's bot detection programming. My money is on Google heh",
"You can sure, but the button is looking for signed the thing doing the clicking is a predictable robot rather than an unpredictable person.",
"Usually there are 2 parts to the \"I am not a robot,\" button. The first part is the checkbox. This is a little more than just a checkbox. From the second the page loads, it's capturing mouse movement data along with some other metrics. When you actually click it it analyzes this data to see if you're mouse moved more like a robot or like a human. If you pass, then that's usually it. If you fail this (clicked too fast to capture meaningful data, you're IP address is sketchy for some reason like a VPN, you actually are a robot, etc.) then it will send you to the \"click all the stoplights,\" to validate you actually area human.",
"Because it does more than just detect whether you clicked the box. It measures how you move your mouse, the time it takes you to click, all kinds of things that are hard to fake since humans have so much more random movements than anything less than the most sophisticated bot.",
"I’m a designer, not a programmer, so I include captchas in my programs but I’m not qualified to discuss how this all works in great detail. In theory, it can be done, but robots as we have them now rely on being “taught” the algorithm required and while a robot could learn the necessary algorithms to beat one specific captcha then a thousand and then a million captchas and eventually beat specific captchas, anti robot captchas like choosing specific objects from visually noisy captchas are working hard to beat the bots so their technology is always being updated and refined. This is why generally across the web captchas seem to be getting harder and more frustrating for humans to solve.",
"You can. Then the people making the capcha will come up with something that defeats whatever you did. Then you can try to work around whatever they do. Then they can try to beat your workaround.",
"When you click the ReCaptcha button and you're not prompted to complete an image captcha, it's actually because the browser (and by extension the website) has *already* determined that you aren't a robot. When you first get a new computer (or you clear your cookies) you often will get a ReCaptcha test. Nowadays, technology running in the background allows your browser to store the fact that you completed a Captcha before. It then sends this information to websites that ask for it. Check out [this great Tom Scott video]( URL_0 )."
],
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|
[
"url"
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[
"url"
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lvnzp5
|
How were syringe needles first made?
|
These types of needles are pretty small and also hollow. From what I could find, they were invented in the 1840's so technology was already advancing, but I don’t understand how were they made without modern means.
|
Technology
|
explainlikeimfive
|
{
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"text": [
"> An Irish physician named [Francis Rynd]( URL_2 ) invented the hollow needle and used it to make the first recorded subcutaneous injections in 1844. This link has a picture of His form of hypodermic syringe if you want to look at it. It appears as though this would not have Pierce the skin But rather used as injection into incisions. > The first hypodermic needle was probably made by Francis Rynd in Dublin in 1844, [using the technology of annealing the edges of a folded flat strip of steel to make a tube. This was then drawn through increasingly narrower dies whilst maintaining the patency of the needle.]( URL_1 .) (So many pictures of vintage needles and history of their development. So that is the actual technique that would have been used: making a tube and then making it smaller and smaller. > Then shortly thereafter in 1853 Charles Pravaz and [Alexander Wood]( URL_0 ) developed a medical hypodermic syringe with a needle fine enough to pierce the skin. Alexander Wood experimented with injected morphine to treat nerve conditions. He and his wife subsequently became addicted to morphine and his wife is recorded as the first woman to die of an injected drug overdose. (Richard Davenport-Hines disagrees ‘It is a myth: she outlived him, and survived until 1896')"
],
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12
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"text_urls": [
[
"https://litfl.com/alexander-wood/",
"https://medicine.uq.edu.au/blog/2018/12/history-syringes-and-needles#:~:text=The%20first%20hypodermic%20needle%20was,the%20patency%20of%20the%20needle",
"https://litfl.com/francis-rynd/"
]
]
}
|
[
"url"
] |
[
"url"
] |
lvoaad
|
After learning about something new, why is there an almost uncanny series of events where I run into that thing multiple times?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gpcvoi5"
],
"text": [
"This is called the *Baader-Meinhoff phenomenon* or *frequency illusion*, and it happens precisely because you're now more aware of the thing than you were before you learned it. Your mind is primed to notice it, since the human brain is really good at noticing patterns."
],
"score": [
71
],
"text_urls": [
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|
[
"url"
] |
[
"url"
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|
lvoer5
|
How do paintings or artworks by renowned artists have ridiculous prices? Is rarity the only factor for its high cost?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gpcxm0m",
"gpczaov",
"gpd0fqi"
],
"text": [
"Because purchasing them is a dick-waving contest between billionaires. When you have so much money that you could never possibly spend it all in one lifetime the only things that have real value are things no one else can have.",
"The price is a feature, not a bug. A significant portion of the purpose of the cost of owning the original rather than a very good copy is the exclusivity offered by it. There are very few luxuries that are solely available to the very wealthy - even things like Ferraris are well within the reach of upper end professionals. If you’re a billionaire and want to show off your options are: Massive estate + house Yacht Private Jumbo Jet Art and antiques Of those only one is portable, and the price is whatever you want it to be. The higher the better. Then you get to fob it off to a museum to provide security for it while they throw you a big party in your honor that you get to invite your fellow billionaires to to lord it over them. The other part of the high prices is, in some cases, money laundering, and again the higher the price the better - can move more $$$ on each transaction.",
"As other posters have said, the art is more than just art; it's concentrated wealth and a vehicle for prestige. It can also be categorized as an investment, which makes it even more attractive among the cohort of people with the disposable cash to enter the market and play the game. Conspicuous consumption acquires its own velocity up until the point of a crash, and then it can rebound all over again."
],
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10,
4,
3
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"text_urls": [
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|
[
"url"
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[
"url"
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|
lvooxz
|
When new medicine commercials say 'Don't take NewDrug™ if allergic to NewDrug™', how would you or doctors know you're allergic to it?
|
Biology
|
explainlikeimfive
|
{
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"text": [
"Because many drugs are the same just with a different brand name or there is a component of the drug which you may be allergic too. Before you ever try a new drug always consult a medical professional. They may even recommend you get an allergy test if anything in the drug is known to be a common allergy. For example, people allergic to eggs need to check with their doctor before getting the FLU shot.",
"Chemistry. Even with a completely \"new\" drug, pharmaceutical companies know the chemical composition, and they can make comparisons to existing drugs with similar compounds and make ~~educated guesses~~ predictions. So if you're allergic to Demerol, and New Drug™ comes out that has ingredients in the phenylpiperidine class, you'll *probably* be allergic to New Drug™ too.",
"Previous experience taking the active ingredient, as part of the product being advertised OR (if applicable) another product incorporating that active ingredient.",
"Years ago my little niece pointed this out. She also pointed out the \"if you or a loved one died or were injured\"."
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18,
6,
3,
3
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[
"url"
] |
[
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|
lvorxb
|
How well do animals with eyes on the sides of their heads see forwards?
|
Biology
|
explainlikeimfive
|
{
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"gpcy88r"
],
"text": [
"Not that well. They often have a blindspot in the middle of their vision, and even those that don't still tend to have weak depth perception. Thing with animals with eyes on the side of their heads though is that they don't really need to be able to see in front of them - they're looking at plants most of the time anyway. It's much more useful when you've got your head down chomping on grass 80% of your day that you can see the things to the sides of you, not the ground infront of you.",
"Not as well as animals with their eyes pointing forward. Those with eyes on the sides have a wider range of vision, and are more likely to notice predators. Those with eyes in front are hunters and need to best focus on what they're trying to catch."
],
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3
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|
[
"url"
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[
"url"
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|
lvpnbp
|
How is the height of a wave measured?
|
I just saw an article about a world record wave being surfed, and I have no idea how they can be so sure of the exact height of the wave.
|
Physics
|
explainlikeimfive
|
{
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"text": [
"Judges use the known height of the rider to compare the height of the wave on pictures taken of the ride."
],
"score": [
3
],
"text_urls": [
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|
[
"url"
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[
"url"
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lvpw4y
|
why do chickens and turkeys have bumpy skin under their feathers?
|
I tried googling it but all that comes up is dermatology conditions in human like psoriasis.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpd479y",
"gpdbidc",
"gpd4g4p"
],
"text": [
"Thats where the feathers connect. We have tiny hair follicles, they have big feather follicles.",
"The bumps are there to allow the seasoning to stick better for fried chicken. It’s god’s helpful design.",
"The bumps are small muscle groups the birds use to raise and lower their feathers. If you’ve ever seen a little bird all puffed up for warmth on a cold day, that’s those little bumps. Mammals have a similar function to fluff up their fur. Human ancestors did too once upon a time, but we’ve since ditched the fur to better handle warm environments. Your body will still try though when you get cold, hence the goosebumps."
],
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6,
5
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|
[
"url"
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[
"url"
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lvqf03
|
- How can cameras capture and display ultraviolet light as a violet color?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gpd6rib",
"gpd84v5"
],
"text": [
"Think of it as just a translation. Theres a lot of the light spectrum we can't see. So when we build a camera that can, we also build a program that can displace that light in a color we can see: purple.",
"The color cameras capture and the color shown on screen aren't related to each other in any technical way. All the image sensor sees are black/white images through different color filters. The screen then takes that data and turns on the appropriate color of pixel by that amount. But there's no reason one can't just use another color of pixel than what the camera \"saw\". Or make a camera that sees different colors, and then just map them to the red, green and blue pixels on a screen. This is called false color imagery, and is used extensively in non-visible spectrography to visualize data. For example, one might assign the 3 colors of a screen to the absorption lines of different molecules, and make a map of what's where that way."
],
"score": [
4,
4
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|
[
"url"
] |
[
"url"
] |
|
lvqgie
|
why does a tv make small purple dots when in contact with a finger
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gpd80vl"
],
"text": [
"Liquid Crystal Displays or LCDs work by polarizing or not-polarizing (passing or blocking) the light coming through from the backlight. When you press on an LCD, you are deforming the crystals (bending them), which causes them to change their polarization a little. [Here is an AskScience thread]( URL_0 ) that may be helpful."
],
"score": [
3
],
"text_urls": [
[
"https://www.reddit.com/r/askscience/comments/q14ib/why_do_lcd_screens_change_color_when_i_apply/"
]
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}
|
[
"url"
] |
[
"url"
] |
|
lvr0g6
|
Why do some bodies exude more body heat than others?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpdceto"
],
"text": [
"Please I need to know. When my 7 year old hands me the stadia controller it's about to melt..."
],
"score": [
4
],
"text_urls": [
[]
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|
[
"url"
] |
[
"url"
] |
|
lvrxrv
|
s,p,d,f orbitals and how are they different?
|
What I get so far: Each electron shell can have multiple orbitals. First (closest to nucleus) shell only has the s orbital. Its field (space where the electrons can be) is a sphere. Two electrons max. Starting with the second shell, in addition to the s orbital, there can be (or always is?) 3 p orbitals. Their field is "shaped" more like a teardrop or a balloon. I'm not sure about d and f. The brief explanation I read makes it sound like they're limited to some elements (lanthanides and actinides?) unlike s and d. (I assume d starts with lithium but you get me) But said source didn't elaborate much, leaving me with some questions that can be hard to find answers to (that don't look Greek to me). I'm not sure what their "shape" is, but probably more importantly: when do atoms have d and f orbitals? At first I assumed that it goes, from hydrogen onward like this: (I'm going from the innermost shell and using the plus sign to separate shells) 1 shell: 1 s orbital with electron 1 shell: 1 s orbital with 2 electrons 2 shells: 1 s orbital with 2 electrons + 1 s orbital with 1 electron 2 shells: 1 s orbital with 2 electrons + 1 s orbital with 2 electrons 2 shells: 1 s orbital with 2 electrons + 1 s orbital with 2 electrons and 1 d orbital with 1 electron .... 3 shells: 1 s orbital with 2 electrons + 1 s orbital with 2 electrons and 3 p orbitals with 2 electrons each + 1 s orbital ... 4 shells: 1 s orbital with 2 electrons + 1 s orbital with 2 electrons and 3 p orbitals with 2 electrons each + (ditto shell 2) + 1 s orbital with 1 electron ... Basically, start with shell 1, it has only s, fill that up, second shell can have s and p for 2+2+6=10 total. Third shell can have what the second one has plus d, and atoms with three shells can have up to (2)+(2+6)+(2+6+10)=28. Is that the way it goes?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
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"text": [
"My man, this can't be answered with ELI5 because the answer to your question cross the quantum territory.",
"The periodic table shows visually which elements have which orbitals: The first row has 2 elements. That's a full s orbital. The next rows have 2 + 6 elements. That's s & p. After that, you'll see 2 + 6 + 10 elements in a row. That's s, p, d. After that, the lower two inset rows make a tally of 2 + 6 + 10 + 14 in a row. s, p, d, f. The \"shape\" of each orbital's probability distribution derives from the general \"shape\" of a wave in 3-D space around a point center, which are a group of general solutions called [spherical harmonics]( URL_0 )."
],
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[
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[
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lvseqv
|
Why do we instinctively smile when happy or joyful?
|
My 4 month old smiles whenever she recognizes somebody yet she’s too young to have learned/been taught/mimic this.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpfec3s"
],
"text": [
"She's not too young. She's been watching the other people around her for four months, and focused on their faces. I read a study when my kids were little where they took newborns and stuck their tongues out at them to see how early they could learn to copy it. One little girl was able to copy it when she was only 8 hours old!"
],
"score": [
5
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|
[
"url"
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[
"url"
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lvtold
|
Why does Wasabi feel like it burns in your sinuses/brain instead of your mouth/tongue like spicy peppers?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpdsaqh"
],
"text": [
"Wasabi and related things like horseradish are more of an aromatic effect. It vaporizes and gets all up in your sinuses and stuff and is water soluble so it goes away really quickly. I’ll come back with an edit for the chemical name, I can’t remember. Spicy peppers on the other hand are spicy because of capsaicin which is oil soluble and triggers sensors sensitive to heat. This is what makes it feel like your mouth is on fire. These sensors are also found towards the end of your digestive tract, which is why it burns on the way out too. Edit: It’s called isothiocyanate and oxidizes with air and saliva."
],
"score": [
19
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
lvuuj2
|
Why does our tongue rest at the top of our mouths and not the bottom?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpeob0b",
"gpdzhw0",
"gpdydci"
],
"text": [
"It doesn't for everyone, but if it does for you, then this means you have good oral posture! Your body likely continues to maintain this posture because it has so many good benefits, while resting with your tongue down can cause a lot of problems. The tongue is a very special muscle because it doesn't have skeletal support (you don't have a tongue bone)- it also has the ability to move in many different ways thanks to it having four internal muscles that run in different directions- this means that your tongue is able to move and rest in a lot of different ways. Just as standing with good posture has benefits, so too does maintaining good oral posture. If you stand with your head slumped, you'll notice that your neck, back, and shoulders hurt a lot! Similarly, if you have bad oral posture you might find that it causes pain/ misalignment in the jaw, shoulders, and neck. This is because the base of your tongue doesn't just float around in your mouth- it is connected to a bone called the hyoid, just under your jaw in your neck, which is connected to your Adam's apple/ wind pipe/ vocal chords in turn by different muscles- your Adam's apple bobbing when you swallow actually helps close off your windpipe to protect your airway! Your facial and neck structures also play into your mouth posture a lot because the mouth is so important for breathing and feeding- two of our most essential functions. In fact, if you rest with your tongue down, you're likely to have a visibly 'weak' chin (which can be improved with improved posturing if it is from tongue placement < 'mewing' > - sometimes though, people really do just have small jaws). Some of the benefits of good oral posture include: preventing dental crowding/ tooth grinding or clenching and therein decay, preventing pain in your jaw joint (TMJ), helping you breathe through your nose instead of your mouth (better for filtering air and also warming it up, which is good for your respiratory system), and maintaining the roof of your mouth (your palate) which is important for swallowing (by closing off the nose)/ helping with chewing and for speech. Your tongue should also be at the top like this when you swallow so resting with your tongue down may make your swallowing less effective unless you have other medical conditions that would make tongue down swallowing safer (like if it takes a longer time to close your windpipe). Finally, bad tongue positioning may be associated with having more middle ear infections because a little tube runs from the back of your mouth to the space behind your eardrum- this helps your ears 'pop' after airplane rides.",
"It could be due to what language you speak. Since you speak english, the tongue will rest at the top to more efficiently produce the most common english noises. If you want your tongue to rest at the bottom, learn russian.",
"The tongue expands in the mouth to seal off the throat so nasal breathing doesn’t involve the oral cavity? And so saliva in the mouth doesn’t constantly drain into the throat but rather is controlled by swallowing so as not to get sucked into the throat whilst breathing. I don’t know. That’s just my guess."
],
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5
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[
"url"
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[
"url"
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|
lvvhvf
|
why do leaves turn yellow when damaged or dying?
|
What happens to the chlorophyll? Like I am aware of Chlorophyll a and Chlorophyll b. So is it like the A one degrades and B remains?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpe2742"
],
"text": [
"Both chlorophylls are broken down and either used by that leaf or exported to the rest of the plant. With no chlorophylls, what you see is the other pigments - usually carotenoids. The colour you see is what isn't absorbed by the plant. * Chlorophylls absorb mainly reddish and bluish light, they look green. * Carotenoids look orange, yellow, or red (they make pumpkin/carrots orange). * Anthocyanins look red, purple, blue, or black So as the plant reuses the pigments, the leaves go from green (chlorophylls dominate) to yellow/red (carotenoids dominate)."
],
"score": [
6
],
"text_urls": [
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|
[
"url"
] |
[
"url"
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lvwuvp
|
How do lightning storms on earth compare to those on other planets? And can we replicate other planets lightning on earth?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gpeaywe"
],
"text": [
"We photographed lightning on Jupiter in 1979. The lightning flashes were 10 times as powerful as anything recorded on earth. So why would you want to recreate that?"
],
"score": [
8
],
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|
[
"url"
] |
[
"url"
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|
lvx1p5
|
how does the instinct work? How can animals and insects know what to do by them selves?
|
Biology
|
explainlikeimfive
|
{
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"They don't really know. Your behaviour is influenced enormously by your body chemistry. You eat because you're hungry, you fight because you're stressed, you mate because you're horny all of these behaviours are driven by your body's chemistry. A spider has no idea how to build a web. It just has behaviours that essentially add up to building a web. Let's figure it out by going back in time and looking at how spiders developed this behaviour. The earliest spiders that made silk likely only did so as a method of protecting their bodies. Many invertebrates that can produce silk or similar substances do so to create a soft protective shell. Like caterpillars about to cocoon or burrowing spiders that line their burrows with silk. Spiders that actively go out to hunt, also leave a trailing line of silk. Primitive spiders like tarantula's leave a line of silk wherever they go and follow that line back home. And evolution rewards beneficial behaviour simply because animals that are predisposed to beneficial behaviour pass on the genes that result in that behaviour more often. The spiders that protected their bodies better and had an easier time finding the safety of their burrows survived more often and reproduced more often than the spiders that didn't. Over time, laying down a navigation line became standard behaviour for spiders. And the evolution of that is laying down lifelines. Hunting spiders that actively hunt usually lay down a lifeline everywhere they go. If the spider falls (or even jumps), this line acts as a safety stop. Again, very beneficial behaviour so something that is easily passed on through selection. Spiders with safety lines just survive more and reproduce more than spiders that didn't. And when you think of spiderwebs, you think of those beautiful wheel webs. But there's a lot of different kind of webs. The earliest and most primitive spider webs are really nothing more than a series of tripwires on the ground that alert spiders to movement near their burrow. And those also evolve gradually. The earliest spiders probably just randomly strung wires along the ground. But the spiders that spun patterns that efficiently provided the best coverage had more success than the ones that made a mess of it. Over time, spiders would develop natural inclinations towards spinning lines in effective ways. Over time spiders developed a staggering variety of ways for using webs. From throwing sticky bola and lassoes to trampoline webs that launch prey into a net. But none of them actually know and understand what they're doing. Wheel web spiders start their webs by finding a spot with good airflow and letting out a line until the wind catches it and sticks it to a spot across a gap. The spider will then traverse that initial line and build the web around it. The spider has no idea why it does this but building a web in locations of airflow means flying insects are more likely to fly into the web. Spiders who preferred building webs in areas of high airflow simply had more success and reproduced more often. Anyway, the point is that these things develop very gradually. Animals (and humans) don't think about instinctive behaviour. They just allow their body chemistry's reward and punishment systems to guide their behaviour. You don't have to understand the biological reason you need to eat to realise that a feeling of hunger is sated when you eat.",
"It just took a lot of time and many generations. So notice how for us (humans), being in cozy, warm safe space feels nice. Now imagine that many many generations before, beaver ancestors felt pressure to build some sort of housing. So some of them were good at it, and survived, and some were bad and died. And those whose survived passed on their genes, and their urge to build good, strong dams. You can link it to our feeling regarding tidying our environment, or pleasure we get from hair brushing, or cleaning ourselves. Those who felt such urges, had better chances of survival, because they were in save environment, they were getting rid of their parasites, they kept clean and relatively healthy. And they passed on their genes. And those traits evolve generation after generation. Its enough that feeling urge to build good dam gives you slightly bigger change of survival, many generation later every beaver will have this urge. And this goes on, and traits become more and more refined. Its not that they start as perfect dam builders, it requires lots and lots of generations."
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[
"url"
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|
lvxla1
|
Since we are supposed to be consumers, what would happen to the economy if everyone drastically reduced the amount of money they spend on a regular basis?
|
Economics
|
explainlikeimfive
|
{
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"Less consumerism means fewer sales. Fewer sales mean fewer profits. Fewer profits mean downsizing, lost efficiency, lost jobs, businesses closing down, markets shrinking. It's really quite problematic because from an environmental perspective we should be massively downsizing our consumerism. But it also results in significant socio-economic problems if we did.",
"The economy contracts. Businesses close. The money you do not spend loses value, everything gets more expensive. You spend the same money like today for less goods. The economy simply adapts to the lowered demand.",
"Assuming this was done via people saving more it could be quite bad, savings are a type of demand leakage, where more money in circulation doesn't lead to more money chasing goods and services. The best chase if this happens is that the private sector shrinks rapidly and the government massively expands the public sector to help maintain employment until spending habits can support a larger private sector again. Unfortunately as many politicians are absurdly worried about public debt they'd likely do the opposite and add fuel to an economic depression.",
"That's exactly what a recession is! When we go into recession, money doesn't just disappear, but instead people spend more slowly. If you were confident about your economic prospects you might choose to buy a $100 pair of shoes. The shoe store owner then takes his wife out for a $100 dinner, and then the chef buys a new $100 knife, and the knife store manager pays $100 for his son's soccer league, and the park district spends $100 on new sports equipment, and... So in good times, that $100 generated $500 in economic benefit. If you were worried about your job, you might choose to save that $100 in case you need it for groceries or rent in the future. Now it's not generating all that subsequent economic benefit.",
"It depends on what people do with their money and what time frame you're talking about. If everyone put their money under their mattress effectively removing it from the economy, you would have some economic contraction immediately. The credit markets would contract most though as we but tons of crap on credit. That, to me, wouldn't be a bad thing. It would be for the people who work at Visa/ MC. If people put it in their banks, then the banks would have more reserves, and in a world where interest rates are controlled by the free market, banks with more reserves would be compelled to try and offer more loans to get that money working. With demand reduced as stated in the situation, they would need to offer lower interest rates to draw more customers. The rates would float down enough to eventually attract more customers who want to invest or buy things on credit (you can see this now with how housing is in a bubble due to low interest rates atm). However, we don't have an interest rate set by the market but by The Fed. And they will do what they do, and no one really knows how they'll manipulate the market. Given the recent history though, they'll probably keep it low to boost consumption again. If people put it into other investments like the stock market or businesses, then you would see economic expansion. If your situation only addresses consumers in the US, then companies would quickly find international markets. The sick market would be in an interesting position of having more cash introduced to buy shares in companies that are losing sales. But not all companies lose during economic contraction. Low end brands tend to do very well. People go from buying Mercedes to Kia, or from eating out to eating box macaroni. Basically, think of the economy like an ecosystem. It will find it's balance naturally if you let it. Government manipulations and interventions can be used, but it's like trying to play God. And everyone thinks they're dealing with a fish tank that can be predictably controlled when they're really dealing with the ocean."
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|
lvye5n
|
What does this quote mean?
|
"and who looks at a shadow when then have a flame? Who would ever choose a monster over a god?” - **King's Cage by Victoria Aveyard.** I get the god part, but I don't get what the shadow part means. "When then have a flame?" Is that even correct english? If it's old english for "they" then I still don't really get the meaning behind it or how I could apply it to life.
|
Other
|
explainlikeimfive
|
{
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"gpeeq5g"
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"text": [
"I took it to mean “ why would you be scared of the dark when you have the torch/light? You are the cause of the shadow” kinda thing. I could be totally off base here and wrong but that’s my interpretation"
],
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4
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[
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[
"url"
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lvyizf
|
The golden ratio. Just, in general. What is it? Why is it so important? What’s special about it?
|
Mathematics
|
explainlikeimfive
|
{
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"text": [
"Geometrically, the golden ratio is most easily understood as the dimensions of a 'golden rectangle'. The golden rectangle's special property is that, if you cut it into two pieces so the larger piece is a square, then the smaller piece will be another smaller golden rectangle. [Here's a diagram of that.]( URL_0 ) The golden rectangle has been cut apart into a blue square, and a red rectangle, and that smaller rectangle has the same proportions as the one we started with. That's the unique property that makes the golden ratio golden. Now, why is it important? That's a little harder to answer in a general way. This ratio pops up in the solutions to all kinds of different problems in totally unrelated areas of math, including number theory, analysis and geometry. It appears when something keeps getting added to its previous iterations, as in the Fibonacci or Lucas numbers. It appears when you look for fixed points in a lot of systems related to the exponential function. It also is the angle which can fill in angles around a circle most uniformly, which means it's found all over a lot of plant anatomy, in cases where plants have to arrange a lot of somethings around a central something. Pine cones, sunflowers, things like that. [Here is a wonderful exploration of why that is.]( URL_1 )",
"You have two numbers. The ratio from the smaller (B) to the bigger (A) is equal to the ratio of the bigger to the sum of both. So A/B=B/(A+B) This is only true when A/B is the golden ratio 1.618... This is important for some mathematical things, for some specific measure this number can be considered the \"most irrational\". It's the value that the ratio of the fibonacci sequence approaches, and optimal in several situations (for example if you interpret it as an angle and let leaves grow with that angle apart they have the least overlap, therefore some plants follow this) In the art the golden ratio is considered very aesthetic. So you try to divide things in a way that represents this ratio. Especially often done in architecture.",
"The golden ratio, commonly represented as φ (or Phi), is a special ratio (similar to the much more famous Pi). Specifically, the golden ratio refers to a special case where the ratio a/b is equal to (a+b)/a, and is related to the Fibonacci sequence (which is a special sequence of numbers that, gradually, ends up forming a method to approximate the Golden Ratio). It has some interesting applications in geometry and logarithmic mathematics. ***However***, the Golden Ratio is also horrifyingly overhyped by popular science, new age cults, and modern artists. For example, it is commonly claimed that the Golden Ratio carries \"aesthetically pleasing qualities\" in architecture and art, with the Parthenon being offered up as proof, despite the fact that architects and archaeologists have never found any evidence of Phi being used in the proportions of the Parthenon. Similarly, many will point to [Nautilus Shells]( URL_0 ) as an natural appearance of the Golden Ratio...when usually the Golden Ratio never shows up (there are a huge range of ratios that end up creating logarithmic spirals that look like a nautilus shell). Ultimately, Phi is just an interesting phenomena that got overhyped by people who want to find some sort of objective measure of \"beauty\" in nature, even if such a measure has no real basis in reality. tl;dr Phi is to actual artists as the idea of Ancient Aliens is to actual historians."
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"https://upload.wikimedia.org/wikipedia/commons/thumb/8/8e/SimilarGoldenRectangles.svg/1200px-SimilarGoldenRectangles.svg.png",
"http://youtu.be/lOIP_Z_-0Hs"
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[
"https://upload.wikimedia.org/wikipedia/commons/0/08/NautilusCutawayLogarithmicSpiral.jpg"
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|
[
"url"
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[
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|
lvypnz
|
What is a chameleon’s field of vision like and how does it stitch together the images of both their eyes? Is it similar to how humans do it?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpegofi",
"gpeg1gj"
],
"text": [
"Here is a link to a video that talks all about the true facts about the chameleon. It is vastly entertaining and he has other tire fact videos to help you in your understanding of life’s little mystery. URL_0",
"Well nobody knows the perceptual experience of a chameleon of course. But the two fields of vision aren't integrated in a chameleon, or in lots of prey species like deer (that have an eye on each side of their head). They have two separate fields of vision. That seems weird to us because we have binocular fusion, but I guess its just normal for them."
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3
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"https://youtu.be/UR_byRbXxvs"
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|
[
"url"
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[
"url"
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|
lvyvu6
|
Some dry powdered baby formula milk has probiotics bacteria, does the bacteria actually live in the dry powdered? Or the bacteria is created after the milk has been mixed with water?
|
If it has live in the dry powdered, what does the bacteria eat for months if the can is unopened? Does it multiply the longer we store it? If it is created after mixing with water, how does the bacteria become alive?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpeh4nx",
"gpely7t"
],
"text": [
"These bacteria are freeze-dried (i.e. no heat is applied, which could kill them). Without water bacterial cells stay in a kind of suspended animation. They resume active life when you add water to the powder.",
"Just wanted to add the reason we can’t bring back people from being frozen is because our body is mostly water. When the water freezes, it forms “crystals” which cause damage at the cellular level."
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3
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|
[
"url"
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[
"url"
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lvzib5
|
Why do we sweat salty water and not just water?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpfonkr"
],
"text": [
"Electrolytes. We can’t have pure water running through our veins. Our cells would burst. We need sodium chloride (salt), potassium, and others to keep our fluids in check (homeostasis). That’s why if you are really thirsty and you drink a fair amount of water you feel bloated, tired, and crampy. It’s also why people that chug a ton of water skip into coma and/or die."
],
"score": [
6
],
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|
[
"url"
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[
"url"
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|
lw07t8
|
How are small children able to master gymnastics moves, such as a handstand, seemingly effortlessly?
|
It took my little cousin less than a week to do a handstand for thirty seconds, yet I am still attempting to do it against a wall. How?!
|
Biology
|
explainlikeimfive
|
{
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"gpfdyhg",
"gpemly7",
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"text": [
"Children usually have less mass and a lower center of gravity than grownups. It is literally easier to do a handstand at 5 than at 25. Less strength and skill and coordination is required and even if you account for the fact that adults have more strength, and better coordination than week clumsy children, they come out ahead. It is also harder to hurt yourself when falling down as a small child due to physics and children are generally more fearless and will not hesitate when adults would, which helps with gymnastics a bit.",
"Besides the physical, there's also the mental aspect of it. Younger brains are better at learning new things and making new connections. Also, kids don't understand risk and injury so are less likely to be afraid of hurting themselves. This means they might be able to push themselves more than an adult. A kid feels a wobble and either deals with it or falls. Either helps them learn. And adult feels the same wobble and immediately gives up for fear if injury.",
"Handstands in particular: tight hips will make it difficult to maintain your balance. Kids don't have years of sitting working against them yet.",
"Flexibility, shorter (lower centre of mass for easier stability) and also because children can learn really quickly so learning something new takes less time (not sure how much it would apply to hand stands though",
"Children's brains are in a unique developmental point when they are prepubescent (even teenagers in the later stages of puberty) where they can learn things extremely quickly, from riding a bike to swimming to speaking a different language. Their brains are literally 'wired' for it, adults, having gone through a neuro-pruning (a real thing, look it up), we don't learn novel things as quickly and the things we tend to learn serve to reinforce things we already knew. That is why it takes a kid minutes to learn how to ride a bike but much longer for an adult woman. Swimming is even worse, it takes *forever* for an adult to learn to swim compared to a child and it will never seem very natural. This is one reason why parents are obsessed with 'enrichment' programs like music, water babies, foreign language immersion schools, etc, it all lines up with the science. Plus, there is the fact kids are fearless, bouncy, have a lot less mass, and are more injury resistant."
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[
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[
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lw09ys
|
How can our body control passing gas versus defecation when you have the need to do both?
|
Most of us are probably familiar with the feeling of when nature calls, we might not be able to attend to it, and we pass some gas to get some temporary pressure relief (and sometimes it doesn't quite work out as we planned and... well... shit happens). If the urge is the same, and the mechanism of release is similar, what is it our bodies are doing differently to control the release of one but not the other?
|
Biology
|
explainlikeimfive
|
{
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"text": [
"Gas only needs a small opening to escape, where as a bowl movement needs some pushing and a larger opening, unless you have diarrhea and that's when the ol shart happens.",
"You actually have several \"fart or shit\" sensors in your anus. It detects what's coming out and opens the sphincter appropriately.",
"You've also got these things called rectal flaps at the end of your large intestine that help catch poop from leaving when it's not supposed to."
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45,
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|
[
"url"
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[
"url"
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lw0fp6
|
How do brain cells die and what happens when they do?
|
Biology
|
explainlikeimfive
|
{
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],
"text": [
"There are any number of ways brain cells can die. Like any other cells in the body if something happens to causes them to be unable to continue to function they will cease. They stop metabolizing fuels and other cellular processes, and eventually will break open. The body’s cleanup cells will collect the now waste cell bits and recycle or expel them. As for the brain as a whole it will attempt to adapt to the loss of the cells, and it is usually pretty good at this. Small numbers being lost are imperceptible, larger numbers usually result in some loss of function, and excessive amounts result in death.",
"Your brain, or rather your Central Nervous System, is an integrated organ. If brain cells die, which happens when there is a lack of nutrients and oxygen to sustain the cells for some other medical reasons, the organ that is your nervous system does not work as well as before. The field of neuropsychology and neuropsychiatry are diagnostic and medical fields centered around determining, what the actual results of such incidents are. The cognitive effects are so varied and vast that it's hard to say what actually can happen, as the brain, especially the human brain, is a little bit too complex for the scientific community to figure out completely at this point in time. Hemispatial neglect, dementia, death, aphasia, mood swings, coma and agnosia are some examples of what MAY happen when your brain cells die on a significant level."
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[
"url"
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[
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|
lw0la3
|
Is Open Source Encryption really more secure than Close Sourced Encryption
|
And how so? It feels like because everyone can see the code, it would be less secure, but many people say that programs like signal and bitwarden which use open source encryption are far better than other closed sourced alternatives.
|
Technology
|
explainlikeimfive
|
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"text": [
"They are, not from a technical perspective (both open and closed source software can be great, and both can be trash), but from a philosophical perspective. Encryption exists because distrust in third parties exists. So why should I trust someone to make good encryption software, when the precise reason I use it because I don't want to trust strangers to not abuse my data? If I can't verify what the software does with my data, I could have forgone encryption entirely, since it's just shifting trust from \"I believe you won't do anything bad with the stuff I give you\" to \"I believe you didn't intentionally/accidentally make bad encryption\". Open source is verifiable, and therefore removes the requirement to trust the vendor. e: now one could argue that most users aren't competent to check the source code themselves even if they could. But simply the fact that it's out there means that sooner or later, problems will be identified by someone and the word will get out. That's already a huge incentive to do your work properly as a vendor.",
"\"Here's my closed source encryption. It's unbreakable. I'm not going to show you how it works, but trust me, I promise it's unbreakable. Really-for-real. Honest!\" \"Here's my open source encryption. It's unbreakable. See for yourself! I'll show you exactly how it works so that you can trust it. Oh, you figured out how to break it? Here's version 1.1, and I fixed the problem you found.\"",
"> It feels like because everyone can see the code, it would be less secure This is kind of an illusory feeling of safety. Even if your encryption method is secret, that doesn't mean there aren't attacks that can end up revealing it (known-plaintext attacks, chosen-plaintext attacks, side channel attacks...). In cryptanalysis, it's generally assumed that determined attackers will eventually always know the *method* of encrypting messages; you should concentrate on[ keeping the *encryption key* secret instead]( URL_0 ).",
"You can see the code and test it yourself, you know that they haven’t implemented some backdoor they can use to see your messages even if they are encrypted, and the fact that many people are looking for exploits by looking at the code actually makes it more secure, because good guys can also find vulnerabilities and report them However that doesn’t necessarily make the encryption itself any safer, you can have really safe encryption without it being open source, it just makes it more trustworthy, rather than having to believe a company’s marketing",
"A lot of points have already been addressed, so I’ll just comment on this bit: > It feels like because everyone can see the code, it would be less secure. Encryption is just math. To keep it “ELI5,” think of it like “pick a random number between 1 and 1 billion.” The fact that you can see the workings under the hood doesn’t make it any easier to guess the randomly picked number. In fact, seeing the source code lets people verify that the random number generation truly is random. It would certainly be possible to write a bad encryption program that *says* it’s picking a random number between 1 and a billion, but just always picks the number 7. That would obviously be terrible encryption, but if the program was open source, everyone could see it and publicly call them out. If it was closed source, we might not know how terrible the encryption is until it gets hacked.",
"Imagine two bank vaults with a lot of money inside them. One has been kept secret in the back of the building, and nobody has ever tried to break into it. The other is built into the middle of a public square, and anyone is welcome to try to break into it any time, yet nobody has succeeded. Neither vault has ever been broken into. But which one do you think is likely more secure? Both vaults, public and private, might be very high quality, but because the public one can be tested by anyone, flaws are likely to be identified and fixed. Nothing wrong with closed-source code, but open-source code does have this public-proof advantage.",
"> And how so? It feels like because everyone can see the code, it would be less secure, but many people say that programs like signal and bitwarden which use open source encryption are far better than other closed sourced alternatives. Any time you use closed-source software you implicitly trust the creator on *their* word that the software does exactly what it advertises. You are basically being handed a black box with a button. An important point is also that any piece of open-source software can theoretically be maintained, patched and repaired infinitely by a dedicated community. If a software company goes belly-up and does not publish the source code of their proprietary creations, their programs or formats will inevitably stop working or become insecure as the rest of the world moves on. Open-source software has no expiration date.",
"If your encryption can be defeated by people knowing how it works it's an awful encryption scheme and you should never use it ever. A good encryption scheme cannot be reversed even if you know *exactly* how it works. The method itself is strong enough that if you do not have the key your best shot is guessing randomly. As such \"closed sourced encryption\" doesn't really offer much additional security even if you don't know how it works. It shouldn't matter to begin with. However the idea is that in the case of open source encryption anyone can see it, identify holes or security flaws, and suggest fixes. It also removes the need for implicit trust: I don't need to trust that you've implemented it correctly and haven't intentionally added any holes."
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[
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[
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lw0rsq
|
What is happening internally when going over a bump or a rollercoaster and your stomach flip flops?
|
Biology
|
explainlikeimfive
|
{
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"text": [
"As you go over the bump, you experience a moment of weightlessness, and then you are effectively falling. This causes your guys to start \"floating\" around inside you. Of course they are all fairly held in place, but the slight movement can be felt. It's the same as if you've ever jumped off of something tall (like a diving board) and felt motion in your guts as you fell. This happens because of inertia, as you start falling, your guts want to stay in place, so they move slightly upwards within your body.",
"I'm a bio student, but no med student. Other people who have pointed to the same organs you point to. I wonder how much the sensation comes from the brains processing of sensory input from the inner ear. The inner ear helps humans sense equilibrium and gives us a sense of balance. The (osseus) or \"bony labyrinth\" contains a complex setup of passages filled with fluid. As our head tilts, theis fluid responds and that response stimulates tiny hairs. The cells the hairs attach to convert this stimulation into a signal that can be sent to the brain. It seems possible that most of our stomach queasiness is generated by the brain's response to this information rather than since information from movement of the organs in our chest cavity.",
"Great question and replies. If anyone can go a step farther and ELI5 why many people with epilepsy get the same feeling (randomly or due to a trigger) I'm very interested in thoughts on that."
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[
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[
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|
lw0xyq
|
If McDonald’s can do cheap food so well, why can’t we feed inmates in prison reasonably edible food.
|
Other
|
explainlikeimfive
|
{
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"text": [
"I think your knowledge of cafeteria style foods is limited to movies or something haha. Do a bit of googling around and you'll find that cafeteria food in schools, hospitals and prisons is actually pretty damn good in most countries.",
"It's not that we can't, it's that we choose not to. It varies from place to place, but prisons spend anywhere between $0.56 and $2.50 per day to feed prisoners. Even McDonalds prices would be at least 2 or 3 times more, which would cut into the profits of the private prisons. It also doesn't help that we dehumanize people in prisons to such an extent that the general population is completely apathetic to their treatment (if not maliciously in favor of mistreating them because 'they deserve it').",
"The food in hospitals and schools, isnt bad per say, it just is low in salt, and low in spices... You could have the best ingredients, no salt, no pepper, no spice... tastes bland, and shitty"
],
"score": [
7,
6,
5
],
"text_urls": [
[],
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|
[
"url"
] |
[
"url"
] |
|
lw2cj3
|
When you turn a cable television on with a remote, is the TV or cable box actually responding directly to the remote, and how is the other triggered?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gpexach",
"gpexdbu"
],
"text": [
"They are both always listening for a signal. When they receive a signal they are programmed to respond to in a certain state then they act. Example: Your TV recognizes when you hit the volume button even when off, but will only turn the volume down when the TV is on. If the remote is set up to trigger the cable box then the TV, it’ll send a power on signal to both devices. Some TVs will power on when they receive a new video signal such as when a connected device turns on. It really depends on by the capabilities of your TV and your remote.",
"The remote has an infrared emitter, and the device you're turning on has an infrared receiver. They will communicate a command like \"on/off button was pressed\". Everything after that is handled by the device you just turned on. If the remote is for your TV, then it's the TV handling all of that; If the remote is for the DVR, receiver or cable set, it would be that device handling the command."
],
"score": [
6,
3
],
"text_urls": [
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
|
lw2e2f
|
Why do babies have crazy core strength?
|
Why are babies so strong despite not being muscular? They can lift their legs repeatedly and “plank” when held. What age does that innate strength go away?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpeyokz"
],
"text": [
"I suppose it's another application of the square-cube law. In short, strength and durability are proportional to the size squared (X\\*X) and weight is proportional to the cube of the size (X\\*X\\*X) so if you take a human and shrink him proportionally to half size, he will become 4 times weaker but 8 times lighter, so in total it would be twice (8/4) as easy for him to lift his own body. Babies have different proportions and their muscles are less developed, of course, but still they are much smaller than adults so it's easier for them to do these tricks."
],
"score": [
22
],
"text_urls": [
[]
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}
|
[
"url"
] |
[
"url"
] |
lw2f9u
|
Why is that our hands start shaking when we are trying to hold something steady without any support and it gets harder the more you try to concentrate.
|
Try holding a pen steadily for a few seconds, the shaking is easily visible. Also make sure your hand is not taking support of anything. The more pressure you use to keep the pen stable, the harder it gets (the hand/fingers actually sort of starts vibrating). But while moving the pen our hand keeps it smooth and steady. Is this also related to old people who can't keep their hands from shaking?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpfpkw5",
"gpf6o6p"
],
"text": [
"Just FYI there's no real way around this, but the more you concentrate on keeping your hand or fingers steady the worse it will be. Focus on your shoulder/arm and how that keeps the pen in place with the wrist firm but not locked and the hand relaxed. People with excellent handwriting use their shoulder to manipulate the whole hand because that gives the smooth stroke they need. The further from the core the weaker you get. It's an odd sensation using the bigger muscles for small movements at first but once you get the hang of it you wonder how you ever did it the other way.",
"It’s because of the way your muscles work. Think of your arm like a robot. You are holding a pan in mid air. To compensate for the weight of the pan and keep it from going down, what do you do? Easy, you just put a muscle on top of the arm (your biceps) that creates a force upwards. That force and the weight of the pan will cancel each other out, right? Except the only case they will cancel each other out is if they are perfectly equal to each other. And while a robot may have the computing power to know exactly how much force it must apply to the muscle, your brain does not. There will likely be a moment where the force of your muscle is slightly bigger than the weight of the pan, and you’ll end up slow-no slapping your face with the pan. So you need to correct for that, and because it’s easier to correct it than to expect your muscle to follow a super quick successions of orders like “release a tiny bit of fraction - no that was too much - ok you’re goo- ah nope too little now”, you’re going to need a counterforce. So you put a muscle at the bottom of your arm (the triceps), and by balancing those two muscles and their force, the goal is to be able to control the position of the pan more steadily. The issue now is you have two opposing forces trying to compensate for the weight of the pan, and that’s a whole lot of forces that are hard to keep exactly equal. So as your brain tries so hard to keep that pan where it is, and as your muscles do their best to follow the brains orders, your muscle cells might get a bit tired, or lazy, or rebellious, and let the other side take over for a split second It’s essentially tug-of-war. Except the baked egg on your pan is in the balance"
],
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3,
3
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|
[
"url"
] |
[
"url"
] |
lw2fws
|
Despite being unbelievably rich in resources, why is Africa home to some of the poorest countries in the world?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gpf1v3x"
],
"text": [
"In economica this is actually known as the resource curse or Paradox of plenty. Although you would typically think that natural resources would be great for everyone, there are a few reasons it is not. I will try to keep this eli5, and link toa post with some more detail. First, people care more about what the government does with their taxes if they are paying a lot in taxes (so they have \"skin in the game\"). In a resource rich country, a majority of government revenue may come from the tesource industry, which means that while most of the populace pays low taxes, they also care less about good governance, and this may encourage mismanagement and corruption in the government. Second, Resource extraction only narrowly benefits certain people. The mining companies for instance may make a lot of money, ultimately means that only a few people in the country become ultra wealthy, a small number of workers for the country may live good lives, but most people in the country can only benefit from natural resources through govt taxation (see above for problems) Third, countries that have an abundant resource may not benefit the most from its extraction. Raw materials are just that, raw materials. In most cases, the cast majority of value in a product is its processing and effort, not the value of the raw material. So unless a country is able to develop the means to process and refine the raw material, along with the related industries, they may recieve relatively little economic benefit. Finall, related to points 1 and 3, resource rich countries may focus only on the extractive industries, and not invest in other sectors of their economy. This means that the country may be very susceptile to shock related to their natural resources, and further limits the rest of the economy which is not involved in extraction. A good overview can be found here: URL_0"
],
"score": [
3
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[
"https://www.google.com/url?sa=t&source=web&rct=j&url=https://resourcegovernance.org/sites/default/files/nrgi_Resource-Curse.pdf&ved=2ahUKEwiC9ezv5pHvAhWIVs0KHb01CzAQFjABegQIBhAG&usg=AOvVaw1GEbReYB7xC24_b76QWBIX&cshid=1614695637831"
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|
[
"url"
] |
[
"url"
] |
|
lw34bw
|
a small leaf pile will destroy the grass underneath it quickly, but an even thicker snow pile that lasts for months throughout the winter seems to have no effect. Why?
|
Editing just to say thanks to everyone who has contributed. The responses make perfect sense!
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpf1il9",
"gpf1nyj",
"gpfao0e",
"gpfdhyr",
"gphaftz",
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"text": [
"A few things, In cold temps, plants go into hibernation mode. It uses the energy it stored up to ride out the covering of snow. Also leaves are highly acidic. To many in a given area will change the properties of the soil. Finally, is the leaf still living? Fresh leaves still absorb sunlight, even off the tree!",
"Snow is just water, and most northerly grass is well conditioned to handle dormant months under snow. Tree leaves aren’t just water, and may even be intentionally poisonous. Plants aren’t always passive observers to the forest, they’re active participants and they compete with eachother. Sometimes this competition is quite vicious, and many trees have evolved leaves that don’t just rot away to nothing on the forest floor, but rather salt the earth below them to exterminate any nearby competition. The chemicals (and if it’s big enough, the heat) released by a rotting leaf pile can kill any living plants nearby.",
"Turf generally has a four things it does in a year. 1) Actively growing. Times are good, weather is warm, the turf is trying to grow and spread as much as possible. 2) Actively storing energy, The seasons are changing and the turf is preparing for winter by loading up on carbohydrate reserves in the perennial parts of the grass (stems, stolons, rhizomes.) 3) Dormancy. The grass is too cold to grow and done storing energy, it goes to sleep until the weather turns again. Turf turns brown. 4) Preparing to grow. The weather is warming up, but not warm enough to grow. The turf will turn from brown to green using all the stored energy it saved up in the fall. It does a combo of use the stored energy to grow and starts storing more for when it is time to grow. All that to say, that in dormancy, the turf can handle being covered for months, it is hibernating and doesn't need any sunlight. Leaves (any kind of shade really) can be really harmful because the turf needs the sunlight in all the other times of year. Whether it is trying to grow, or storing energy, shade is a major hinderance. Grass will spend all of its energy trying to get above the shade thus exhausting its energy reserves. That is why turf in the shade grows much longer and less dense that turf in full sun. Any trampoline owners out there? It is trying to get more leaf surface area to do more photosynthesis. Oftentimes, a late snowfall can be really devastating for turf as well. The turf has used up its energy reserves to come out of dormancy and then gets covered again for an extended period of time can wipe it out. Of course, not all turf is the same and there are major differences in species and varieties, but for the most part, this is true of all turf grasses.",
"The simplest explanation, grass can't grow through even a relatively thin mat of leaves. Grass is never trying to grow when covered in snow, but it IS trying to grow in spring, and leaves can still be around in spring. If you anything that covers up plants, they will try to grow and find sunlight, but eventually will die. If you rake up those matted and wet leaf piles in mid- late- spring, you will find green shoots of grass trying to grow underneath. However, they only have so much energy and are unable to push directly up through the leaves, so once that stored energy is gone, and they have not yet found light, the grass dies. This is literally the exact process that most weed barriers use. Weed barriers ONLY cut out light, they let water through and do not change soil conditions, but you will find that after awhile, there are just no more weeks growing because they all tried, and died. Grass is still just a plant.",
"The moisture buildup, warmth, and lack of airflow kills the grass. Basically starts a mini-compost pile. Look up what happens when you cover soil with cardboard sheets. [ URL_0 ]( URL_1 ) I don't agree with other comments here about leaves being acidic or lack of nitrogen in the leaves. It's not like grass will die without a steady stream of organic N being fed to it, and composting leaves typically don't have any substantial effect on soil pH (and the top leaves don't decompose fast enough to have any effect at all).",
"I think the last thing to add to the aforementioned comments is that, in a leaf pile there is a tonn of life, insects and worms eating away at things, breaking down the leaves, which releases chemicals from the leaves as well as releasing their own faeces and chemicals seeping onto the grass.",
"Couple things at play here. In winter the grass is dorment so it is not trying to grow or absorb any nutrients. It doesn't NEED the sun in winter. In fact the snow can help protect the grass. The snow is at a stable temperature just below freezing. Without the snow the grass can be exposed to MUCH colder temperatures and strong winds causing winter damage especially if the grass is tall and unmowed. In fall the grass is still trying to grow so the leaves will block all the sun preventing any photosynthesis. Also if there is any moisture, the leaves will keep it from drying out so it's just wet and dark underneath, great for disease and bugs to grow helping kill the grass faster."
],
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"https://en.wikipedia.org/wiki/Sheet\\_mulching",
"https://en.wikipedia.org/wiki/Sheet_mulching"
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[],
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|
[
"url"
] |
[
"url"
] |
lw3ctj
|
The US 2nd amendment says "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed." But gun owners are not members of any well regulated militia, how does this now allow anyone to own a gun?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gpf28hp",
"gpf293k"
],
"text": [
"Believe it or not, this went to the Supreme Court and they decided that the comma after \"free State\" meant they were describing two different things. The second amendment separately protects the right to a well regulated Militia, as well as the right of the people to keep and bear Arms.",
"US courts have largely held that the first clause is not a limiter of the second clause, merely an explanation of intent. You could read it as \"Because a militia is important, the people should be allowed to keep and carry arms.\" Under that interpretation the first part doesn't *restrict* the second part, just explains the reasoning behind it."
],
"score": [
4,
4
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
lw3fn9
|
Why so so many cows have a black & white fur?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpf4zig",
"gpfas1g"
],
"text": [
"You’re just seeing the same breed of cattle. Probably [Holstein]( URL_0 ) It’s kinda like asking, “Why do so so many dogs have white coats with black dots”? You’re just seeing a lot of Dalmatians.",
"European settlers brought the livestock they knew best to lands very similar climate/land-wise to the Old Country. Hence all the Holsteins and Herefords. In warmer climates the cows are [much different]( URL_0 ). You'll find that variety in Mexico and Brazil as well because they're heat and pest-resistant."
],
"score": [
17,
3
],
"text_urls": [
[
"https://en.wikipedia.org/wiki/Holstein_Friesian_cattle"
],
[
"https://www.thecattlesite.com/breeds/beef/76/zebu/"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
lw4a11
|
- Is there potentially a limit to the amount of data our brains can hold?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpf8d3a",
"gpf8dyh",
"gpf9ofn"
],
"text": [
"Yes, anything in our universe is made of a finite number of things, and even using every single atom in the universe to store data would have a potential limit, regardless of how large",
"Of course, your brain is finite and it contains a finite number of neurons. The awesomeness of the brain is more related to the ability to erase information than the ability to store if flawlessly. Talk to any prosecutor, they'd much rather have a grainy security camera tape or a drop of DNA than an eyewitness to a crime. People mis-remember stuff all the time.",
"So I'm a lawyer and you may have heard tell about how hard law school is. Some of my classmates transcribed lectures verbatim and then produced summary documents hundreds of pages long that they virtually memorized before the exams. I took notes by hand, usually one or two pages per lecture. My summary of courses was 10-20 pages of handwritten notes. A decade later I remember basically all of that, and my classmates have forgotten basically all of their material except the stuff I wrote down. Why? Or brains slowly summarize stuff. You don't remember much of your childhood but you probabably remember a summary. The further forward in time the simpler the summary can get. That's the brain. If you were a thousand years old you would probably remember the entire 1300's as a few meals, a few friends, and a whole lot of boring. What happened there months ago today? Nothing important so you remember almost nothing."
],
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3,
3,
3
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|
[
"url"
] |
[
"url"
] |
|
lw4q1r
|
How do snake bellies stretch so much when they eat?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpfeafl",
"gpfaoha",
"gpffurd"
],
"text": [
"Snakes have between 200-400 vertebrae with as many ribs attached! That is what makes them so flexible and helps them move along! All those bones and the strong muscles protect the internal organs. The throat of the snake takes up the front one-third of the body. It leads to a really long stomach, which, like the throat, will stretch to the size of whatever the snake is eating.",
"The rather blunt answer is \"because they can.\" The larger the snake (in width), the more nutrients it needs to sustain a larger body. So if a snake were to devour smaller prey, prey that wouldn't 'stretch' the body, it would be hunting nearly nonstop. This would be detrimental to the creature as it would be burning energy constantly on the hunts, where in reality its adapted to be able to devour something large (i.e. less hunts, more nutrients), and stretch to consume it. That's the purpose of its adaptation, to get the most out of doing the least.",
"I'm going to try to describe this the best I can from memory (herpetology class/former hobbyist). Certain scale types on certain parts of a snake's body overlap but don't necessarily connect directly. In between these scale types is a soft, stretchy type of skin that allows for expansion where more rigid scales wouldn't. When a snake eats an especially large meal it may stretch to the point where this stretchy, in-between skin becomes visible as the scales separate. I think it's most obvious on the lower jaw as the snake is swallowing it's meal. Sorry if that was explained poorly, and hopefully someone will correct me if I didn't get it 100% correct."
],
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5,
3,
3
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"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
lw5cmp
|
How does a logarithmic scale work vs a linear scale?
|
I've always had a mental block on what exactly a logarithmic scale is showing, vs a standard linear scale, e.g. on time-series charts. I'm now 30 and I feel like it's something I should understand by now! Can someone explain to a dumbo like me?
|
Mathematics
|
explainlikeimfive
|
{
"a_id": [
"gpfdh4s",
"gpfdxf7",
"gpfhw5e"
],
"text": [
"Linear scale: First notch represents 1. Second notch represents 2. Third notch represents 3. Logarithmic scale: First notch represents 1. Second notch represents 10. Third notch represents 100.",
"With a logarithmic scale, increasing differences in values are shown with the same spacing. So if you think of a graph, with one axis being numeric values from 1 - 1,000,000. The spacing of 1-100 would be the same as 100-1000 even though it is an order of magnitude larger. This is a means of \"compressing\" data so that small initial changes can be viewed in relationship to larger scale growth. A linear scale graph would have the 100 - 1000 section be ten times the size of the 1-100 section, because the data is treated as a 1-1 scale.",
"One way about it is that straight lines on a linear scale correspond to constant rate of *change* (e.g. always growing by $200), straight lines on a logarithmic plot show constant rate of *growth* (e.g. always growing by 20%). Put another way, logarithmic axes are good at representing *ratios*. For example, if metric A is always twice as much as metric B, that's easy to see on a logarithmic plot, where that \"twice as much\" ratio is a constant offset. Put yet another way, linear scales preserve *additions* and logarithmic scales preserve *multiplication* - or perhaps more accurately, \"logarithmic scales turn multiplication into addition\". So for example, going up by 2cm on a logarithmic plot might translate to \"multiply by 1.5\", no matter where on the graph you are. This is actually my favorite way of thinking about logarithmics in general - I use logarithms in a context where multiplication is hard but addition is easy. (That's why they're used as the basis of slide rules)"
],
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12,
3,
3
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"text_urls": [
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|
[
"url"
] |
[
"url"
] |
lw6agk
|
Why does lightning look like it goes upwards instead of downwards?
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gpfk114"
],
"text": [
"Because lightning does actually go up instead of down. Before a lightning strike (or rather, the discharge - the bit that makes the flash and the bang) happens, what has to happen first is for rogue electrons to form things called \"leaders\" in the air. These are paths of ionised air. Leaders propagate from the cloud down towards the ground, usually splitting into branches. This happens in a jerky motion, which creates the iconic zig-zag shape. In a thunderstorm, objects on the ground are also becoming charged. If a leader gets close enough to the ground, the ground will send out its own leader, and the two will eventually link together to form one complete path of ionised air between the cloud and the ground. When this happens, a massive electrical field is generated at the point of attachment (and that point is very close to the ground, because the ground only starts making its own leader when the incoming leader is already close). The electrons here speed up all of a sudden and then shoot out back along the leader, and because this starts close to the ground, the electrons are moving upwards. The electrons are going so fast and with so much energy that they cause the air in the leader to turn into a superheated plasma that's so hot it glows briefly, which is what you're seeing in a lightning strike. And because the electrons are going so fast, it also makes this process of heating happen practically instantaneously. This makes the air expand so much it causes a sound wave, which you hear as thunder. Lightning is cool as shit."
],
"score": [
13
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
lw6r22
|
how come doctors can reattach severed limbs and make them work, but can't fix spinal injuries that cause paralization.
|
Arms, legs, fingers, toes can all be completely separated from the body and then reattached and work fine, doctors can patch together nerves and all that so the person can feel and move and use the limb that was detached. Why can't they repair spinal Injuries the same way to make people walk again.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpg8xz2",
"gpfltrx",
"gpfm28x"
],
"text": [
"Generally speaking, we actually ***aren't*** amazing at reattaching nerves yet. The reason why we're good enough at reattaching hands, feet, fingers and toes is that their movements are actually not controlled directly by nerves, but rather by tendons further up in the arm/leg. So the doctors can restore movement by making sure that these tendon connections are restored, but it's mostly up to the body to regenerate the neural pathways. And it's not particularly fast at that.",
"Because spines contains a lot lot more tiny nerves and each of them must be reattached exactly like before which is very difficult if not impossible with current technology.",
"Although surgeons are very good at their job most of the work regarding reattaching limbs is done by the body itself. If you put cells next to each other they will manage to fuse the flesh together and make things work out in some way or another. Most cell types and organs is very good at this as they get damaged fairly often and it does not matter that much if they do not heal back to exactly how it was before. The problem with nerves is that they grow slowly, in general they do not regenerate although there are some exceptions. It also matters how they are connected so if you change the connections around the signals will not be able to work properly. So while small nerve damages in the limbs caused by amputations will heal over time as they connect roughly to where they originally connected the chance that a huge nerve cluster reconnects in a usable way is very low."
],
"score": [
8,
4,
3
],
"text_urls": [
[],
[],
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}
|
[
"url"
] |
[
"url"
] |
lw7gmc
|
Why is it that when mixing colors on computers/phones, the maximum “amount” you can use of each is specifically 255?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gphk9et",
"gphkpf4",
"gphmgy8"
],
"text": [
"When you have a byte ( 8 bits ) to represent the color, the values are between 0 and 255 because in binary that’s the maximum value 11111111",
"Rgb are historically store as 6 hexadecimal Numbers (2 for each color). 2x16=256 possibilities.(0 to 255)",
"The amount of each primary color (red, blue, and green) is represented by a single 8-bit unsigned integer. Binary values range from 0 to 2^n - 1, where n is the number of bits in the integer representation. For an 8-bit integer, that range is from zero (binary 00000000 or hexadecimal 00) to 255 (binary 11111111 or hexadecimal FF). That is for each color, but of course you have three colors that can be combined in any proportion, so the actual possible number of colors is 2^24 = 16,777,216. This exceeds the number of colors which scientific consensus seems to indicate can be differentiated by the human eye, which is approximately ten million, so a more complicated representation is not required. It is certainly possible though. For example, if you used a 16-bit integer for each color, the range for each would be from zero to 65,535 (2^16 - 1), and the total possible number of colors would be 2^48 , or approximately 2.8 x 10^14 colors. This would be wasted on human eyes though and isn't worth using twice the storage space to encode color information for every pixel."
],
"score": [
7,
6,
5
],
"text_urls": [
[],
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|
[
"url"
] |
[
"url"
] |
|
lw85xv
|
Body produces fever to deal with infections. How is this slight change in temperature (average is 37° and fever is 38°) generally enough to kill the microorganisms?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpftesr"
],
"text": [
"There is controversy on how effective if it actually is but the theory is this - Your body contains molecules called proteins that VITAL to your life. Usually proteins are wound up into tiny little balls, like yarn. But when you a heat a protein is starts to unwind and it cannot be wound back up again. This is what happens when you scramble an egg for example, you cannot unscramble an egg. The theory is it's a war of attrition, your body warms up just enough to start damaging the proteins of the invading microorganism, this might kill them, or it might just slow them down enough for your immune system to kick into kill them off. Since your body is much larger it can wait out the microorganisms and survive."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lwa69s
|
What’s the difference between A.I and a really clever piece of software or computer?
|
We are seeing a lot these days about A.I but I have seen a few things where I’ve thought, that’s just something a piece of software can do...why are we now calling it A.I?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gpg8ed5",
"gpgknxm"
],
"text": [
"Well, \"AI\" means so many things that it doesn't mean much, it's very like \"software\" in that regard. The best chess and Go players are programs, but their \"intelligence\" is very, very narrow. The better term might be AGI, artificial general intelligence. This is \"intelligent like a five-year-old\", including the ability to learn anything with focused education. AGI would be substantially different from the cleaver software we have today.",
"We’ve been moving the goalposts for what counts as AI for a few decades now. In the early days, one of the milestones to making an AI was making a computer that could beat a human at chess, which lead to advancements in game theory, and some very skilled computers. When they finally beat humans at chess, we realized that a specialized computer wasn’t really intelligent and the definition of a “true” changed. That’s happened with pretty much every milestone. Image recognition? Difficult, not intelligent. Machine learning? Cool party trick, but it’s still specialized. Can it hold a conversation? You programmed it to do that. That last one (passing the Turing test) was considered one of the biggest goals in AI research, but it has its own problems. One famous thought experiment known as the Chinese Room compares a talking computer with a locked room and a bunch of (non Mandarin speaking) people who follow directions. If you send a message into the room (in Mandarin) and the people inside have a massive rule book that tells them what to respond, so that you always get a coherent response (also in Mandarin), are you speaking with anybody? Does the room itself count as intelligent? Basically, it’s a big question that philosophers have been dealing with for ages. There’s no good answer."
],
"score": [
5,
4
],
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}
|
[
"url"
] |
[
"url"
] |
lwbo6i
|
If minerals are rocks/metals ( i think ) then how do they get in foods or in our body?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gpgf9tp",
"gpggtdc",
"gpgf29e",
"gph7hhz",
"gpgff81",
"gpgfki5",
"gpgfn1d"
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"text": [
"\"minerals\" in this sense are just elements of the periodic table, i.e. individual atoms or molecules of iron, zinc, calcium, phosphorus etc. Plants take them up through their root systems and create complex organic compounds with them. Magnesium for example is very important for the photosynthesis in green plants. Animals eat that with their fodder (and sometimes just lick stones, e.g. goats) and deposit it in other complex organic compounds doing important stuff. Red blood cells and liver cells contain a lot of iron, for example. Alls of these are important because their chemical properties are necessary for our complex bodies to work properly.",
"Minerals are made up of elements which can be metallic or not. Minerals are almost always ionic compounds (or more accurately ionic crystalline structures), which means that there are typically both metals and non metals involved in order to make up the positive and negative parts of the ionic structure. It’s not that metals are always positive or always negative, they can be either, but it’s just how ionic structures work that they have a metal and non metal involved, eg. Sodium chloride (table salt) is the mineral halite — NaCl — so it’s a positively charged metal and a negatively charged non-metal bonded together to form a mineral. They get much more complicated than that, but you get the idea. So minerals at the Earth’s surface generally get broken down in a chemical sense by rainwater — this is (chemical) weathering. The different elements making up the mineral get split up and they go on to make some new mineral (clay minerals are a common weathering product of many minerals in igneous and metamorphic rocks), or they get dissolved into water and end up in the sea thanks to rivers. In the sea these elements find a new home by sticking to sediment particles or getting utilised by marine organisms for their soft parts or their shells (calcium gets used extensively for calcium carbonate shells of all sorts of marine life), or just being part of sea salt for a long time before they cycle through deep sea hydrothermal systems. If the elements get utilised in the soft parts of marine organisms which then get eaten by other marine organisms — you can see how elements start to move through the ecosystem up the food chain. These sorts of food chains and cycles happen on land too, some of them connected to the marine food webs, some not so much. The big picture is what ecosystem chemistry is all about, or what is often called biogeochemistry; that is, the natural chemical cycles of all the different elements as they move through the inorganic environment (atmosphere, oceans, rocks) and through the life inhabiting different environments. We eat some of the life on this planet, and all life uses the chemical elements that Earth started off with. You’ve heard of the water cycle or the carbon cycle — well all chemical elements have their own cycles and we inevitably take part in some of those at certain points. An example: iron is a common element in the rocky planets of our solar system. The Earth started with a lot of iron. Much of it formed the Earth’s core early on, but there was so much that the little left over still makes iron a major part of most minerals in the mantle and crust. Rocks in the crust undergo weathering near the surface which contributes to soil. Plants grow in soil and they take up iron — iron is an essential micronutrient for almost all living organisms. In plants, iron is involved in the synthesis of chlorophyll, and it is essential for the maintenance of chloroplast structure and function. So those plants growing in the soil love to take up a bit of iron, they have evolved to need it in order to photosynthesise. This is no mistake — iron is so common in many rocks it’s inevitable that it is a part of soils almost everywhere, so life was probably always going to make use of it. Animals eat plants and take up the iron. We eat animals and take up the iron from them... or we just eat certain plants directly (shoutout to all the vegans getting their iron direct from the source). Our bodies use the iron to carry oxygen around in our blood, to help synthesise new DNA, to initiate the production of essential fatty acids, and probably a load of other important stuff. Creatures die, they decompose, they return iron and all the other chemical elements making them up to the soil or the groundwater or the bugs that helped eat them. It’s a regular old Lion King style circle of life.",
"The soluble ones get in your food. Think of salt. Salt is a mineral. It dissolves in water into Na+ and Cl- ions. So do other minerals. We do not need the minerals as such, we need those specific ions.",
"There are trace amounts found in the environment almost everywhere. Microbes feed on this and concentrate it inside themselves and the nutrients travel up the food chain up to you.",
"Rocks and salt are the same thing. It can be different types of minerals but they are still the same class of chemical structure. And they share a lot of the same properties. So in a dietary sense it is easier to think of minerals as salts rather then rock. Minerals will dissolve in water or other chemicals. And cells walls will let minerals through using osmosis. Plants and bacteria is able to extract minerals from the ground this way. And when you eat food that contains minerals these will also be extracted by your digestion system. But you are also able to get minerals directly, for example by drinking water that have flowed through stones and dissolved them slightly. Some animals will even lick stones directly or eat dirt in order to get enough minerals in their diet.",
"All living things require trace amounts of various minerals. These minerals generally enter the life-cycle through plants. For example water might run over a rock and leach out trace levels of iron or copper. A plant absorbs this water because water is yum and now the plant contains trace levels of the mineral. A cow eats the plant, we eat the cow. Etc. Many modern foods are heavily processed, and many modern eaters eat garbage food, so we need to add artificially add those trace minerals back into our diets through \"fortification\". If you check out a cereal box you'll see a little blurb like \"fortified with iron!\" they literally add iron filings (in very small amounts) to the cereal during production. The problem with this is just because the mineral is *present* doesn't mean the human body can absorb and use it. This is called bio-availability. Eating a cereal with iron filings is not as good as eating beans, or seafood, or red meat for example. this is why eating a variety of healthy, natural foods will always be nutritionally superior to eating food *fortified* with nutrients, or taking a multivitamin.",
"When we say \"minerals\" in the nutrition context, we mean inorganic elements we need to live, like sodium, potassium, magnesium, etc. That's to distinguish them from organic molecules we need to live, like vitamins or proteins. We don't literally mean rocks or metals...elements in those form generally aren't digestible by us, if you eat a rock, you just poop out a rock. Rocks that dissolve are a notable exception...that's how salt works, but that's not common. We need to get the element as part of a molecule that we can digest, that's called \"bioavailability\". We do that by eating things that already incorporated the element we care about into some other organic molecule that we can digest. So when we say \"bananas contain potassium\" we don't mean literal elemental potassium metal (which is a very dangerous substance), we mean \"bananas contain a molecule with potassium in it that we can break down to get access to the potassium.\" If you eat iron fillings, you'll poop iron filings (please don't eat iron filings). But blood, from most animals, contains iron in the hemoglobin molecules so we can get iron by eating blood or stuff that contained it, like meat."
],
"score": [
6,
5,
4,
3,
3,
3,
3
],
"text_urls": [
[],
[],
[],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lwc3bv
|
What causes nightmares and why do we experience them?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gph8lc7",
"gpi6ywu"
],
"text": [
"I don't know the answer to your question but I do know that you are statistically more likely to have a nightmare if you sleep on your left side.",
"Dreams and nightmares are theorised as being the brain's way of processing memories and information when the body is asleep, a nightmare is quite possibly a reliving of trauma or a recollection of distressing memories or information the subconscious is processing at the time. Negative things in the subconscious generally cause nightmares such as guilt, suffering, grief and embarrassment. May edit for more information later"
],
"score": [
3,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lwc787
|
Why do stars I see in the sky flicker? I noticed that stars at night flicker and some don't. Why is that?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gpghsbr"
],
"text": [
"The atmosphere between you and the star has different temperatures and densities at different points, and air's ability to bend light depends on something called \"refractive index\", which depends on temperature and density. So you've basically got a wiggly lens between you and the star, which makes it \"twinkle\". It's basically the same reason you see \"heat waves\" coming off pavement on a hot day. There's nothing wrong with the stars, it's the air. That's why really good telescopes are on high mountains or in space, to get as much air out of the way as possible. Edit:typo"
],
"score": [
9
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lwcmz7
|
Can someone explain this Dangerfield joke? “I told my dentist my teeth were all getting yellow. He told me to wear a brown tie.”
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gpgkwmb",
"gpgwxwf"
],
"text": [
"In most Rodney Dangerfield jokes, people in his life constantly disrespect him and won't do anything to help him. In this case, the dentist is refusing to provide any helpful advice. Instead, Rodney should wear a brown tie so his teeth look white by comparison.",
"The first line sets up the expectation that the dentist will have a direct solution to the problem. Maybe some way to make Dangerfield's teeth whiter. Instead, the dentist suggests a tie color that he thinks would pair well with yellow teeth. The message is \"I can't make your teeth stop being yellow, so here's a way to make it work anyway.\" That's not what you'd expect from the dentist, so it's funny."
],
"score": [
72,
18
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lwco97
|
Do objects move instantly? I vaguely remember a Vsauce video explaining that if an object was long enough it wouldn’t move instantly
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gpgl36w"
],
"text": [
"No, they don’t move instantly, if you’re just pushing it. It takes time (speed of sound in the material) for molecules far from the point you’re pushing to “realize” that the object is being pushed. The object compresses a little bit as long as it’s under acceleration then rebounds when the acceleration stops. If it’s being accelerated uniformly by an external field, like gravity over short distances or some electrical fields, then it can all accelerate together."
],
"score": [
10
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lwdhtb
|
Why does your body feel really hot inside or has this weird feeling for like 1 second after you stumbled or maybe even nearly dropped something important? I guess it has something to do with adrenalin but what does really happen?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpgs2zf",
"gpgtivv"
],
"text": [
"Yes, it does have to do with adrenaline. Adrenaline is released in your body, which causes your heart to beat faster which brings more oxigen to your cells which causes them to burn that oxigen more intensely increasing metabolism and increasing your body temperature in the process.",
"It triggers a physical response that exists to keep you safe from threats. Increased heart rate and blood flow to important limbs, as well as breathing and muscle tension. All of these things cause your body to warm up. The reason it happens when you dorp something (or close to it0 is because the part of the brain that causes that response cannot directly observe the world, it can only act based on what other parts of your brain do. and at that moment, even though you might just be dropping a plate or something, your reaction to it is close enough to a threat response that your brain just hits the panic button. And that reaction is what allows you to catch yourself or an object being dropped very fast, without thinking about it."
],
"score": [
11,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lwean5
|
Blu-ray resolution
|
Why do some remastered films released on Blu-ray mention a “4K Scan” when the blu-ray resolution output is limited to 1080p?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gpgvsoh",
"gph00bm"
],
"text": [
"What they have done is scanned the original film in 4K format and then digitally downsampled it to HD. Normally the digital downsampling process is able to do this process smarter and are able to preserve a lot more features then if you were to scan the film with an HD scanner. For example the downsampling algorithm might be able to detect film graining in the 4K scans and eliminate these effects in the HD output. It is also easier to detect sharp lines and smooth transitions which you can preserve better in the downsampled output. They do a similar thing with 4K movies where they will scan in 8K or 10K before downsampling. At those resulotions you are basically just scanning the invididual film grains anyway. But even when they are shooting new movies digitally they will use 8K or 10K cameras as it gives them a lot more options with digital effects and even things like cropping before downsampling to 4K for consumers.",
"Regular Blu-ray is indeed limited to 1080p but there exists a 4K Ultra HD Blu-ray standard"
],
"score": [
6,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
lwfaka
|
What’s actually happening when an organ is failing/“shutting down”? Is it lack of blood flow and tissue death, or does it just stop functioning in some way?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gph2be9",
"gph29er"
],
"text": [
"Correct, it's both of those things. Organs are just composites of tissues with a similar structure and/or function. They work in concert to accomplish some purpose needed by the body. When those tissues are dead or damaged, the organ looses the ability to perform that function effectively. If your heart fails, it means it not longer has the means to accomplish it's job of cycling blood around the body. If your lungs fail, you can no longer exchange gases from the blood at a level sufficient to breathe on your own. You can see how either of these might easily lead to a chain reaction of multiple organ failure, which is why it's such a big deal when it happens. Hope that helped",
"An organ fails if it can no longer do its essential functions, and that happens because on the cellular level the tissues that make that organ have been disrupted and compromised by conditions such as trauma or disease. It’s easy to imagine if you think of a worse case scenario; if I stabbed your heart it’d squirt blood in the wrong places, it’d become mechanically damaged and the tissues would be oxygen deprived themselves soon after. Now a harder scenario to imagine is something like heart disease - over decades the heart loses elasticity and has its blood vessels narrowed, eventually to the point of heart failure, where the heart can’t meet the body’s oxygen demands."
],
"score": [
8,
6
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lwfnfi
|
Why do some foods taste bland when cold and more flavorful at room temperature or when warmed?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gph3vvp"
],
"text": [
"Think of butter. When it is cold vs. when it is melted. Melted butter will flood over an area at a thin layer, while cold butter is more concentrated and does not deep into the cracks of your counter. A lot of flavour is fat/oils. When they are warmed they are more “out there” and accessible like the melted butter spreading quickly in a thin layer. More of your tongue gets exposed to it."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lwgavj
|
What's the difference between measuring a person's temperature and an object's temperature?
|
I got a contactless thermometer, one of those ones that you just hold near your forehead for a sec. It has different modes for measuring your body temperature and measuring object temperature (plus a room temperature one), and doing a reading on my own forehead in each mode gives different numbers. Why is there a need for the separate modes, and what's it doing differently in each?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gph7v1d"
],
"text": [
"Some surfaces radiate heat better than others, just like some surfaces reflect light better than others. When the thermometer only registers a small amount of heat being radiated by whatever you're pointing it at, that may indicate that the object is cold. But the object could also be hot and not good at radiating heat (such as shiny metal objects). In order to calculate the temperature accurately, the thermometer needs to know what kind of surface it's dealing with. When you set the thermometer to body temp mode, it applies a certain correction factor for human skin, whereas it's going to use a different value for objects, even though that value can only be a guesstimate. The property that we're talking about here is called emissivity."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
lwgze3
|
How do researchers 'gather' atomic and subatomic particles?
|
I always hear about these inventions and experiments where an atom or an electron is 'fired' at something, or a certain amount of nothing BUT the substance being stored. How can scientists control such tiny particles, let alone gather them?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gphcq2i"
],
"text": [
"Old-school TV sets -- before the flat screen era -- were basically a miniature electron beam accelerator, with electromagnet deflection of the beam direction. The same basic physics principles can be applied to making a large electron accelerator, with electromagnets to bend the particle bunches around a vacuum ring, and other electromagnets to keep the bunches nice & compact. To make a proton accelerator, you'd start with a source of hydrogen, and ionize the hydrogen to leave bare protons. Then once again it's electric fields to accelerate them, and electromagnets to deflect them. Some colliders have used antiparticles in collisions. In those cases, they start with high energy matter particle collisions against stationary bulk targets, to spray out particles and antiparticles; then use electromagnets to steer, collect, and bunch up the antiparticles, before they're injected into an accelerator. Again, it's electric fields to accelerate and electromagnets to steer."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
lwhgy6
|
How does vision develop if you need glasses but don’t have them?
|
ELI5: My 4 year old was recently diagnosed with an astigmatism. When we went to the eye doctor she said that if she didn’t get glasses now that her brain would not develop the ability to interpret her vision correctly. So even if she got glasses as an adult, her brain would be formed for vision and she would still not be able to see correctly. Why does this happen? What would vision be like for an adult in this case that never had glasses until they were an adult?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpheng2"
],
"text": [
"Well you see once the eyes see something a certain way for a long time especially before your brain is done developing the eyes and brain will develop to where the eyes are not capable of seeing any better via glasses like how if a deaf baby is able to hear for the first time via hearing aid the baby will cry because it is not use to that"
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
lwievp
|
Why do both the period of pendulums and the period of springs depend directly on 2π?
|
Period of a pendulum T=2π √(L/g) Period of a spring T= 2π √(m/k) Where: T=period in seconds L=length of pendulum g=gravity m=mass k=spring constant
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gphkord",
"gphp8pj",
"gphoun2"
],
"text": [
"Because the differential equations that describe both springs and pendulums are the same, provided that we assume an idealized version of each that doesn't go too far from equilibrium. Namely, both systems' behavior is governed by the equation F = -kx, where F is the force on the pendulum/end of the spring, x is how far from equilibrium it is, and k is a constant related to what specific spring/pendulum you're looking at.",
"The other commenters did a good job of explaining some of the derivation so I’ll come at it from a different angle that might help a bit if you’re not great with that aspect of math. The reason that the numbers all come out nicely related to pi is because of how the sine and cosine functions work. You may remember them as properties of the angles of a triangle (SOH CAH TOA), but they have a lot of other applications because of how these triangle rules work mathematically with the right triangles you can draw using the center of a circle and a point on the circle. And it just so happens that you can use the equations y=cos(t) and x=sin(t) to draw a circle whose radius is 1. This is called the unit circle, and sine, cosine, and the unit circle they create is the basis for an entire branch of mathematics called trigonometry. There’s like... multiple days worth of math class on this subject even at the high school level so I’ll skip to the end. The end result is that the equation y=sin(t) is a perfect way to describe anything that oscillates regularly, like a spring or a pendulum. And because of how the sine function and that unit circle I mentioned interact, this “sine wave” goes through one revolution every (2pi) units of time (remember that the circumference of a circle with radius 1 is 2*pi*radius=2pi. So there are ways to manipulate this equation around to make it fit anything that oscillates, but these equations that we create for it all come back to this concept of the unit circle. If you want good visual aids and more information, I’d suggest googling the unit circle and/or sine waves",
"The force on the object is proportional to the displacement from the origin in both instances^1. When the equations of motion are solved the distance from the origin with respect to time is identical to the “x” displacement of a point moving around a circle at a constant speed. This means the displacement can be described using circular motion, with the acceleration, velocity, displacement represented by sine and cosine functions. The period can also be defined by the angular velocity, in this case sqrt(L/g) and sqrt(m/k), with 2pi being the angular distance covered by one complete oscillation. ^1 the pendulum case is a very close approximation that hold true for small amplitude motion. Once the swing gets large enough the effect of the pendulum moving vertically as well as horizontally throws off the simplified assumptions that enable the above mentioned modeling to work."
],
"score": [
5,
5,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
lwixbn
|
What is the biological reason behind the donkey bray?
|
I tried looking up why/how donkeys make that sound, and every response I find is just people explaining what kinds of things the bray is used to communicate. I'm specifically curious why physically do donkeys have like a two-part noise, the hee and the haw?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gphnwxy"
],
"text": [
"They're the only member of the horse family that can vocalize while inhaling as well as exhaling. That \"hee-haw\" sound. URL_0"
],
"score": [
5
],
"text_urls": [
[
"https://www.treehugger.com/facts-will-change-way-you-think-about-donkeys-4869321"
]
]
}
|
[
"url"
] |
[
"url"
] |
lwjfrj
|
how does bug spray kill bugs?
|
So when the pest exterminator comes to treat my house on a quarterly basis, he sprays this liquid sparingly on the outside parameter of my home. Sometimes (not often) I will find a roach inside my house BUT IT’S ALWAYS DEAD! How does the pest spray work? The pest spray can’t be wet when they walk through it because I find them weeks later.
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gphsxf1",
"gphs6am"
],
"text": [
"It depends on the specific chemical, but a lot of them are some form of insect-specific nerve agent. There are a variety of modes of action, but the most common (afaik) is inhibition of acetylcholinesterase, preventing nerve signals from turning off. This is the same mechanism of action as sarin gas, but the chemicals used will only (intentionally) affect insects.",
"It's likely a potent gas. Bugs can't hold their breathe, so a gas is usually the best way to ensure all of them die. Even if he sprays the outside perimeter of your house, it'll leak in through any cracks bugs would find. The gas probably won't kill them immediately, so they make it a ways inside before rolling over dead."
],
"score": [
11,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
lwjvfw
|
How does hyperinflation in countries like Zimbabwe occur so dramatically and how can it be “reversed” without making everyone billionaires compared to USD?
|
Zimbabwe has 100 billion dollar notes. How does that happen? How can it change?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gpht998"
],
"text": [
"It happens when the government starts printing money hand over fist. In most every instance, it eventually ends with the government launching a new currency and giving everyone a window to exchange their old money for new money at a set exchange rate before the old money is no longer recognized as legal tender. Once I've done that instead of having $100 trillion of old money, I find myself with $10,000 of new money that's actually spendable."
],
"score": [
9
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
lwk51n
|
Why did 16:9 become the standard widescreen format despite 21:9 being the normal aspect ratio for cinema and optimal for content consumption?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gphv88t",
"gphv938"
],
"text": [
"It was the only ratio that fit neatly in all existing standards at the time. see this [image]( URL_0 ) There are numerous sites on the topic. URL_1",
"There were a lot of different sizes being experimented with. First of all 21:9 isn't some magic standard size that we should think about, when the HDTV standard were being developed, there were a lot of thoughts on what to make the ratio and eventually they settled on 16:9 because mathematically, it was the best option and had a good practical capabilities (that you want wider than tall for movies, but too much and it gets weird). I have no idea why you're magically thinking 21:9 is some special or \"better\" ratio. 16:9 became the standard because it was a ratio that basically had a good solution to \"fit\" the variety of different aspect ratios that existed in movies and TV at the time (TV was 4:3 but movies were all over the place). In the end it was just a bit of an equation to find the right aspect ratio that worked the best-- and it was 16:9, thus, here we are."
],
"score": [
11,
6
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"text_urls": [
[
"http://guruprasad.net/wp-content/uploads/2014/06/hdtv_ratio.jpg",
"http://guruprasad.net/posts/why-16-9-aspect-ratio-was-chosen-for-hd/"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lwk6tr
|
What makes headphones "high quality"?
|
Bassy headphones, noise canceling, what makes them sound better then a pair in walmart on a technological level? Edit because I couldnt explain properly: Im asking what makes the sounds and why cheap headphones less great.
|
Technology
|
explainlikeimfive
|
{
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"text": [
"The strength of the magnets used to make the sound. Rare earth elements are required to make magnets strong enough to make \"high quality\" sound. That's why those knock off airpods don't sound quite as good as the real thing, even though they look the same.",
"Apologies, but I don't fully understand. Are you asking why bassy headphones sound better, technically? Like, why are they bass heavy or why do people find heavy bass appealing? I ask as you could absolutely get a pair of cheap bassy headphones, so that's not really the differentiation between an expensive and a cheap set. Counterintuitively, some of the best headphones out there aren't bass heavy, but try to be as neutral as possible.",
"1. Frequency response or driver (speaker) output. Is it being able to create loud enough sounds across the frequency range to be heard? Cheap 5$ headphones typically just have no low frequency output, or it is heavily distorted. 2. Low distortion. Are the sounds clean, or do they buzz at decent volumes? Low distortion requires linear performance of the driver in its range of operation. Meaning, an input wave has to be reproduced truthfully at the ear. All drivers distort. Good drivers distort at higher volumes. 3. Seal. Good seal ensures higher effective volume, by plugging any possible leakage. Good seal also reduces entry of external noise into the ear, and increase signal to noise ratio. Active noise cancelation further reduces external noise, and lets you listen properly st much lower volumes. This means less chances of driver distortion, and a better soundstage. In general, seal is a part of the larger mechanical+acoustical architecture, which includes shapes of components and their coupling to the ear. 4. Signal processing. This, when done properly, makes up for many of the shortcomings of the headphones, be it acoustic performance or mechanical coupling to the ear. Good signal processing takes into account the acoustics of and around the ear, the music being played, etc. so that the listener can utilize the most of their dynamic range of hearing and \"get the most\" out of the music. Then there's stuff like low connection latency, UI/UX, etc.",
"While sound behaviors can be measured objectively, sound preference is very subjective. That said, there are general (read: largely held by a majority of people) sound behaviors that are considered \"better\". You may see terms like \"high quality\", HD, audiophile, reference, etc. First, a given set of headphones (or speakers) will be \"tuned\" to behave a certain way; this is a combination of the materials, design and electronics that are combined to create the headphones/speakers. Second, materials and craftsmanship matter. What the speaker diaphragm is made from (is it cheaper paper - may absorb ambient moisture and change shape/mass over time - or are higher quality and more expensive polypropylene or even metal?), the quality of the inner components and associated electronics, all play a part in \"quality\" A good place to try to answer this question from is to consider what \"reference\" means in this context. Reference is typically used to indicate a sound reproduction that is as close to the recorded material as possible. That means the headphones or speakers wouldn't favor or increase bass (though some people love this), and instead would remain \"neutral\" and let the material speak for itself, as the artist intended. Many purists consider this to the hallmark of quality. But it's not wrong to prefer super heavy xxx bass boomers, if that's your thing, or ultra twinkly high end screamers, etc. Other features (all part of tuning) that generally tend to be preferred and therefore contribute to quality are things like soundstage (how wide - or narrow - the headphones sound), impedance (how hard it is - aka how much power it takes - to \"drive\" a speaker to make sound) can impact how well a speaker conforms to the source material, etc. Lots of bits and pieces here, but you put it all together and you get varying levels of \"quality\". Only YOU can determine which sound is preferable and therefore of \"higher quality\". edit: interesting memory from a long ago time; I've always loved audio equipment, and I spent some time selling high end gear way back in the day ('90s). There was a saying back then: \"No highs, no lows, it must be Bose\"; they were considered to be a more \"pure\" option as they didn't alter or inflate bass, treble, mids, etc. and instead aimed for that \"reference\" sound."
],
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4
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|
[
"url"
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[
"url"
] |
lwk6wi
|
Why does cracking your knuckles have a “cooldown”?
|
Why is it easier to crack your joints if you wait? It feels right, but I can’t fathom why it would be so?.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gphuyi6"
],
"text": [
"Because the \"crack\" comes from fluid displacement from between the joints of the knuckle. The \"cooldown\" time is for that fluid to build back up to enough of a level that it can be displaced again."
],
"score": [
13
],
"text_urls": [
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}
|
[
"url"
] |
[
"url"
] |
lwk76e
|
Why is Devils Tower the way it is?
|
It doesn't look like any of the landscape around it, the rock formation is just super weird in general, why is it like this?
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gphvale",
"gpi0ush"
],
"text": [
"Geologists think it was formed when magma (super hot molten rock) expanded up through an opening in existing rock, kind of like toothpaste being squeezed from a tube. Then wind, rain, and sun eroded the rock around it into the shape it has now, exaggerating any grooves it started with.",
"Its a volcanic plug of granite. The important thing to realize is that it used to be underground! It didn't rise out of the ground, rather, all the dirt around it eroded away and it became exposed."
],
"score": [
6,
5
],
"text_urls": [
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
lwl263
|
How does your body know when to stop or start making blood?
|
Like after you donate blood (or have blood loss from some unfortunate event) what makes your body say "time to make more blood!"? What makes it say "okay I'm full on blood now. You can stop."?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpi0dw4"
],
"text": [
"You have cells in your body that can (approximately) sense how many RBCs you have, mostly in your kidneys, and these cells produce a molecule called erythropoietin to stimulate red cell growth. Conveniently, in the same organ, there are cells that can approximate how much liquid volume you have in your blood, and if you don’t have enough or have too much, it can balance out by getting rid of or holding onto water"
],
"score": [
19
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
lwl4b9
|
the Filibuster
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gpi2jd9"
],
"text": [
"Let's imagine you have a child. You tell your child they have to clean their room before bedtime and they MUST be in bed by 8:00. No exceptions. It's 7:30 and your child says they don't think they should be forced to clean their room before bedtime. They have a bunch of reasons and they explain them all. You're a good parent so you listen to them and acknowledge their arguments. But before you can tell them they have to clean their room anyway it's 8:00. And you already established the rule that they must be in bed by 8:00. So now they get to go to bed and done have to clean their room. Your child has just used the filibuster against you. The rules of Congress are set up similarly. Certain proposals can only be brought up for a certain period of time. If enough senators don't want to vote they can \"debate\" on the topic as long as they want. This is provided for by Senate rules. And eventually the rules require the proposal to be tabled without a vote in order to ensure they can move on to other business and the same proposal cannot be re-introduced until a future session."
],
"score": [
7
],
"text_urls": [
[]
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|
[
"url"
] |
[
"url"
] |
|
lwllhm
|
How does a ceiling fan accumulate dust on its blades?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gpi3pqr"
],
"text": [
"The air that you're breathing acts like a shitty sponge and soaks up small amounts of dirt of water that you can't see. When the fan blades spin they compress the air, which \"squeezes\" it. In the same way that water comes out of a sponge when you squeeze it, those small amounts of water and dirt come out of the air when the fan blade passes through it. That dirt and water mix together and form a sort of cement that sticks to the surface of the fan blade. Water and dirt continue getting squeezed out of the air as you run the fan and so continue to build up on the blades. That stuff doesn't get thrown off when the fan is running because its cemented on there just tightly enough to stay on."
],
"score": [
7
],
"text_urls": [
[]
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}
|
[
"url"
] |
[
"url"
] |
|
lwlwp1
|
Integration and Differentiation
|
I understand the concepts of basic math like addition, subtraction, multiplication and division. All these can be explained in terms of "Apples" eg. 2 Apples + 1 Apple = Three Apples. What is integration and differentiation in terms of Apples?
|
Mathematics
|
explainlikeimfive
|
{
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"gpi6txg",
"gpi50b6"
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"text": [
"Integration: You travel in a car for 3 hours, somebody writes down your speed every minute. Graphing speed and time, you estimate the total distance you traveled. (The area under the curve). Differentiation: You travel in a car for 3 hours, somebody writes down the number on the mile counter every minute. Graphing the distance traveled over time, estimate how fast the car was traveling at various points (the slope of the curve). The wonky math part of integration and differentiation comes in when the curves you’re plotting are based on math equations and not easy to eyeball. For example, for the simple plot Y=X, the slope is obviously always 1, but we can also prove using integration math that the area (Y) from 0 to any given stopping point (X) is Y=(1/2)X^2.",
"someone gives you apples for a while. How many apples did he give in all-- > integration someone gives you apples for a while. How many is he giving you at this instant-- > derivative",
"While arithmetic deals with numbers, calculus deals with rates and areas. The derivative is just a way of describing the *rate* at which something happens. So let's say you have an apple tree. Your tree gives you 2 apples per second. So your derivative d(apple)/d(t)=2. Now let's say your tree starts growing, fast enough that every second, your tree starts giving twice as many apples as it did the last second. Then, your derivative is itself a function of time d(apple)/dt=4t. This can be generalized to nonconstant rates by some rules The integral gives areas, so let's say you were given a rate, 2 apples per second, and an amount of time, 10 seconds. Then you can calculate the number of apples in that time, so 20. Again, this can be generalized to nonconstant areas, or curves.",
"I’ll be curious to see other responses. Draw a picture of an apple on some paper. It’s curvy, right? How much area is inside that 2D apple? Integration gets you the area under a curve. Differentiation is basically the opposite of that. but what is the opposite? If you want to know how much the curve is changing at a particular point, that’s what you get from differentiation. It’s the slope (i.e. the rate of change) at a particular point."
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|
[
"url"
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[
"url"
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lwm4rw
|
How does the body recover from an infection without the use of antibiotics and how can you tell if it's recovering?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpi60ym"
],
"text": [
"Your body raises your body temperature high enough to kill the infection. White blood cells will also attack the infection. Cell by cell they attach to the infection, and the result is carried into your kidneys, and removed when you use the restroom."
],
"score": [
7
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
lwmmm9
|
Why can your body have a "sleep debt" but not a "sleep surplus"?
|
Why does my 15 hours of sleep on the weekend not counteract the 4 hours I get on a weeknight?
|
Biology
|
explainlikeimfive
|
{
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"gpjkwcd",
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"text": [
"Your brain is like a trash can. Throughout the day it fills up with garbage, and at night that garbage is slowly removed. If you don't get enough sleep, only some of the garbage gets taken out. Over time, it builds up until your can is almost always full. A full can is bad and makes you fall asleep or hallucinate. However if you sleep lots and lots, your trash-can can't get under 0% full. It will always only hold a certain amount of garbage.",
"Its like your laptop - once you use is for a while you need to charge it up and if it falls to 0 you need to charge it before it works again but if you leave it overnight the max is only 100%",
"Not getting enough sleep doesn’t let the body and brain finish its cycles. The damage and lack of sleep build up (debt) Once the body is finished with the cycles, that’s it. It can’t store sleep to repair future damage and build future neural pathways. It can only work on what has already been done.",
"You *can* run a sleep surplus, but it doesn't last as long as running sleep debt does. Sleep is complicated; we don't understand fully how it works.",
"FYI It’s not exactly true. You can store up a very limited sleep surplus : it’s called “ prophylactic napping”. It’s essentially done right before an all-nighter. The benefit disappear if you wait. Also it will cover for one night at best. URL_0",
"Since its winter and I am thinking about snow, another ELI5 comparison is how we get rid of the snow. If we don't plow or anything the snow can build up to many feet high, but we can't plow in advance. The road can only be clear at best, but snow can keep building up. Sleep is the body doing a kind of maintenance, it can only get the body to a clear and ready state. The harmful effects of staying awake can keep building up until it's cleared properly.",
"While your brain works, it slowly creates byproducts by standard biological processes, like most of your body, and these byproducts need to be removed from the system. Throughout the day, your brain slowly swells as it works, and this swelling reduces how efficiently your body can “clean away” the byproducts in your brain. You need to sleep so your body can balance the cleaning rate with the production rate of the byproducts. The swelling also goes away when you sleep, as the brain is used less. When you don’t sleep, the swelling doesn’t go away, and continues to increase, making you even worse at maintaining the brain. This is why eventually you can die from lack of sleep. When you wake up well rested, your brain is as “not-swollen” as it can be, and as “clean” as it can be. You can’t get more ready for stuff, and you can’t clean away byproducts that aren’t there yet!",
"Same like you can't pee when there is nothing in your bladder, you don't need sleep before our body has a need for it",
"Your brain is like a bunch of young kids cooped up in a house. Throughout the day, the kids are running around making messes, and the dishes and laundry they use keep piling up. The adult(s) can't take care of the mess until the kids aren't needing constant attention. You can fall behind on tidying and cleaning but even if you have extra time, you can't clean up the next day's messes before they happen. The brain is similar. While it's awake, it builds up \"messiness\" that it can't take care of until it's asleep, when the body and brain slow down enough to focus on cleaning up the mess.",
"Other people have given great answers, but to add - sleep debt is not a very accurate name for chronically under-sleeping. Sleep debt is more like cumulative damage to your well-being, some of which can be repaired by healthy sleep habits. It's really important that people know that sleep debt isn't something you can repay 1:1, you can't constantly get 4-5 hours of sleep and \"catch up\" on the weekend and be square. There was a guy who took this to the extreme in the 90's, inspired by a radio contest. He stayed awake for 11 days, setting a record. When he finally did sleep, if memory serves, he slept like 10 hours? He developed permanent brain damage, antisocial tendencies, and permanent severe insomnia. (And honestly, he's lucky to be alive.) The moral of the story, 5 hours on Thursday night and 11 hours on Friday night does not equal 8 and 8. Be careful out there, folks.",
"Imagine it like a room. The whole day you put all kind of stuff in this room. Big one small one etc. At night somebody ist cleaning it out again to give you space for the next day. If you have a sleep deficit it means that you don't give your little helper enough time to clean out and sweep the whole room. Instead the room might only be half empty and you already start filling it. Now when you sleep longer to balance your sleep deficit. It means you give the little helper more time to clean out the room. Why a surplus is not possible: No matter how mich time you give the little helper, the room cannot be emptied more than, well empty. When it is empty you little helper sits down and takes a break waiting for you to fill the room again.",
"You can bank sleep according to some studies. Military and shift workers who may need to work through sleep cycles can use this to improve mental and physical capabilities during extended wakefulness. URL_0",
"You can have a sleep surplus. There is such a thing as prophylactic sleep. Source am doctor.",
"Explained like you’re five: “fill your sippy cup completely with juice, now try and fit a little bit more juice in.” You can operate on 70-90% juice in the cup drinking and refilling, but you can’t operate above 100% juice.",
"Sleep is your bodies way of recharging and repairing itself. Once your body is *fully repaired* from rest, you can't over-repair it by simply sleeping more. Sleep isn't like fat, or water, or other dietary nutrients that your body 'requires' as fuel to function and thus can store any surplus more than operating requirement. Sleep is about repairing your body, your cells, resting your mind. A great analogy, although lacking additional information, is: *You can't charge a battery more than 100%, roughly speaking.*"
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|
[
"url"
] |
[
"url"
] |
lwnp3j
|
Do volcanic eruptions really bring rare metals and gemstones to the surface?
|
I remember hearing that rare gems are more commonly found in eruption sites, is this common or an uncommon occurrence? And if so who gets jurisdiction of finding and/or selling those gems?
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gpidxln"
],
"text": [
"Yes but much slower than you anticipated I guess. It's more likely to find gems in land that is dominated by vulcanoes for millions of years, so that the land itself is made from vulcanic rock types. A single eruption doesn't do much. It's owned by whoever has the mining rights for the Region."
],
"score": [
4
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
lwoixo
|
If exercise is so good for your mental health and takes advantage of your brain's reward system, why do people forget to do it? Shouldn't it be highly addicting purely for its own sake?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
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"gpj0z39",
"gpihwnd",
"gpihzbu",
"gpiuew8"
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"text": [
"Because it’s a long-term gain more than a short-term gain. A donut i eat now gives me instant satisfaction. Whereas exercising for a month will start to be enjoyable after a while but not as much in the beginning. This is especially true for people who never worked out before.",
"Exercise actually can be addicting! This is because exercise releases endorphins which make us feel happy and 'high'. However, it is also a lengthy process. It takes advantage of our brain's reward systm in the long term. Say you were to start an excerise programme today - along with you taking care of nutrition and other health-related issues - you probably wouldn't see results for quite some time. I'm no expert and can give no numbers in this regard. A shorter path to a feeling of happiness is better because, well, it's shorter. Eating a donut is an instant reward and takes quicker advantage of our brain reward system. Buy donut + eat donut = feel good. Work out + eat well + committment = results you have to work to maintain. It's just a longer and more mentally taxing project.",
"I think most people don’t get addicted to exercise the same way we don’t get addicted to doing chores or working despite the fact that it can help to make us feel more productive and better overall. Without the right motivation, our brains will only see the overwhelming task at hand which is always going to outweigh the reward (that is a sense of a accomplishment in this case). Humans just tend to prioritise what’s easy over what’s healthy, for the most part.",
"I love raspberry jam, it gives me joy but typically I forget to buy or eat it. People don't just get addicted to stuff that has a reward system, if they did, every 90s kid would be a gold star collecting crazy weirdo. Habits and addictions develop when you do a thing repeatedly AND it makes you feel good. Athletes and people who exercise regularly fo start feeling an itch to exercise when they haven't been at their regular time. But that's because a fundemental part of their normal daily routine is missing. Exercise isn't like gambling or binge eating etc because it hurts, it is difficult but then feels good afterwards. That's the difference.",
"Let me give you an analogy. Say you want a pizza...you can get a frozen one, and be satisfied, or you can make one. Getting a frozen one is the non-exercise scenario. You decide that you want to make one. Now you have to think about what you want, then go to the store, and buy the ingrediants. Travel home, and make the dough. Cut the vegetables. Prep the sauce. Dough is ready, now you have to spread it out, add the sauce, put on the toppings, more toppings, and because we are not barbarians, even more toppings. Then we have to bake it, cut it, eat it, and that most terrible of things, wash up after we are done. Frozen pizza? 12 minutes. Not very good, but it'll do. Fresh homemade pizza? At least an hour invested, a lot more work, and if it is a bad pizza, it's your own fault. However, if you make the pizza right, it is healthier for you, tastes better, has EXACTLY the toppings you want in the amount you want them, and if you DON'T follow my personal recipe, probably costs less. My personal recipe also removes the healthy aspect."
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[
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[
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|
lwonct
|
Random quick noises in head???
|
Have had these really weird sounds that I hear for a brief second then goes away, it usually also makes my body jerk. It sounds like a brief buzzing sound fx from a movie or a beep sound.
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gpij8ic",
"gpijff5"
],
"text": [
"I'm also curious, I've had similar stuff a lot of my life, and I've never actually identified them. Some of them sound like very, very sudden built up of tinnitus, and then it goes away. I don't know that i can even explain what i go through, so i can't even tell if it's the same as what you go through...",
"First off, if you haven't already you should consult a doctor when you're experiencing something like this. This isn't a normal occurrence. Tinnitus is a common Auditory issue but it is more of a constant sound, or quickly builds up before going away. Rarely does it present itself in the way you describe or involve muscle tics. Do you have a history of Epilepsy in your family? Some forms of Epilepsy can begin presenting themselves as auditory sounds only you can hear, usually hums or buzzes, along with involuntary muscle tics. Concussive head injuries can also cause symptoms you describe, even years after the incident, so if you've had one in your past, you should definitely consult a doctor and explain these symptoms. Consuming very high amounts of caffeine or nicotine can cause these symptoms too. We're talking like 30 cups of normal coffee a day amounts. (Still tell a doctor.) Lastly, you may be an android. Check if your batteries are running low."
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8
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|
[
"url"
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[
"url"
] |
lwosgv
|
How do humans create amd maintain a body temperature so much higher than their surroundings?
|
I mean from a super-basic level...
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpiiv70"
],
"text": [
"We burn things to keep warm. Specifically, we burn the food we eat. We're basically big complicated engines that use molecules like sugar and fat as fuel to keep us warm and alive."
],
"score": [
11
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
lwq2ei
|
Why does the CCP have such an issue with Uighur Muslims, as opposed to other minorities in the country?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gpioo39",
"gpiz4kb",
"gpj9rul",
"gpirvcf"
],
"text": [
"The CCP plans something called BRI (Belt and Road Initiative), also called new Silk Road. It's basically a program to strengthen their economic influence in Eurasia and Africa. This is highly controversial, but I'll save you the political commentary. Basically, the BRI plans for a southern maritime Trade Route mainly to Africa, and a northern Trade Route to Russia and Europe. This northern route runs through Xinjiang, the Province where the Uighurs live. The Uighurs want independece for this Province, which would put the northern land based route in jeopardy, thats why the CCP does everything in their power to supress this.",
"As the top comment says, China is trying to implement a new silk road called the one belt one road initiative. Xinjiang is in the northwest, so that makes the location vital for their initiative to come to fruition. That's not the only reason why China is so tight fisted with Xinjiang. Years ago, the people of Xinjiang tried to gain independence with the help of other countries. They began calling themselves Eastern Turkemestan and created their own flag. The Xinjiang people who believed in the cause began massacring Han Chinese that were living in Xinjiang at the time. The revolts were snuffed out by the Chinese government, and they began keeping a close eye on Xinjiang in case they would ever try to become independent again. The people of Xinjiang are also Muslim. The Chinese government doesn't like any form of organized religion. Their religion is meant to be their strong faith in the communist party.",
"The simple response is that there has been a history of terrorism within these groups, although whether these groups are CIA backed is unverifiable. The CPC itself doesn't have a problem with minorities or muslims, it's why minorities were exempt from the 1 child policy.",
"Xinjiang is a hotbed of both separatism (which the government obviously dislikes), and Islamic fundamentalism. Theres a history of ethnic conflicts between Uighurs and Han-Chinese that goes even back further than the CCP is in power. The CCP later implemented a policy of ebcouraging Han-Chinese migration in minority regions, further fuelling the tensions. More recently, theres also been series of terrorist attacks conducted by Islamic organizations (supported, among others, by Al Qaeda, the taliban, and more recently even linked to the Islamic State). The whole conflict went mostly under the radar, until the whole concentration-camp-business popped up. [The Wiki-article]( URL_0 ) might be a good starting point, if you want to read up."
],
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|
[
"url"
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[
"url"
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|
lwq8az
|
Why do a few gases start boiling at sub zero temperatures and then freeze at a much lower temperature?
|
Cold is supposed to slow down the particles but boiling means exciting the particles, how does this work? Like HCl (which boils at -83°C but freezes at -113°C)
|
Chemistry
|
explainlikeimfive
|
{
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"text": [
"> but boiling means exciting the particles Boiling does not mean “exciting the particles”. Boiling is the point where the particles are too excited to stick together as a liquid and will fly around on their own as a gas. For every substance there is a range of temperatures and pressures which in combination determine what phase they are within. Increasing pressure tends to raise the temperature required to boil (pushing in from outside makes it harder for particles to fly away), and lowering pressure decreases the boiling temperature. This can be charted in something called a “phase diagram”. Sometimes for a given pressure there is no temperature where a substance is liquid. For example in normal air pressure carbon dioxide won’t be liquid, it is either solid if cold enough or a gas. This is why it is called “dry ice”, it is ice that never gets wet as it warms directly into gas (called “sublimation”). In your example hydrogen chloride (HCl) is a gas at room temperature and standard pressure. It needs to be about -85C to become a liquid, and -114C to freeze into a solid.",
"Temperature IS the sum of kinetic enrgey of the moving particles. When they say something \"boils\" at x° They mean it goes from a liquid to a gas state. \"Freezing\" is going from a liquid to a solid. It all relative to the chemical being discussed. We use water as a benchmark because it is everywhere and we need it to survive. But we COULD actually just set the whole Celsius scale to match with HCL. It just wouldnt be very useful."
],
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5,
3
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|
[
"url"
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[
"url"
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lwqd6u
|
Why does canned food stay fresh at room temperature for extended periods while they spoil in refrigerated environments even in sealed containers?
|
I understand it probably has something to do with the presence of air, but please enlighten me to a scientific level. Thanks!!
|
Chemistry
|
explainlikeimfive
|
{
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"gpipk21",
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],
"text": [
"Cans are sterilized by heating them at high temperatures, killing all bacteria and once the can is shut there is no way for anything to get in or out, so it lasts a very long time",
"Canned foods are put through a process where they are heated after they are sealed. This kills any bacteria inside the cans, and since no bacteria can get into the can until it is opened, the food will not rot. Regular sealed food like in bags do not go through that process, thus the bacteria are still alive, just slowed way the fuck down. They will still cause the food to go bad, just at a much slower rate than before.",
"After they put the stuff in a can, they heat the can like in a pressure cooker. That kills not only bacteria, but also their spores. In the can, the stuff is sterile, basically. You can keep it at room temperature, because there simply is nothing in it that could grow and spoil the food. The moment you open it, bacteria, molds and their spores get in again. Even if you put it into a closed container again and refrigerate it, those microorganisms will start to grow and spoil the stuff."
],
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|
[
"url"
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[
"url"
] |
lwqerp
|
Why do men tend to taller than women?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpipp1u",
"gpkf0jl"
],
"text": [
"It's in our DNA. Men needed to be stronger, bigger, faster etc. to fight off predators, while women could be smaller because they mostly took care of the children and cooked.",
"The trait you're referring to is called \"sexual dimorphism.\" It's present in many, many species of animals but not all of them. Sexual dimorphism's main benefit is it allows specialization between the sexes. Think of it like a business. Say the business makes and sells widgets. Wouldn't it make it more efficient to have employees that specialize in making the widgets and a separate set of employees that specialize in selling them rather than having all employees do both tasks? That's essentially what sexual dimorphism allows. One type of human can develop traits that make them particularly good at one aspect of the population's survival (e.g. hunting by developing greater upper body strength and musculature) and the other can specialize in a different but also necessary aspect (e.g. childrearing by developing enlarged mammary glands to better feed infants). Each side will be better at performing the task they're specialized in than they would be at either if there were no specialization."
],
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7,
3
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|
[
"url"
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[
"url"
] |
|
lwt32p
|
How do naps restore alertness?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpj1rpv",
"gpj3fwp"
],
"text": [
"When you sleep your mind gets refreshed along with your physical body. If you just lay down and don’t fall asleep your body might feel better but your mind will still feel tired.",
"The honest answer is that we’re not really sure. Sleep is one of the least understood aspects of human health from a physiologic standpoint, and we have just loose knowledge of what our brains and body get out of sleep."
],
"score": [
3,
3
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|
[
"url"
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[
"url"
] |
|
lwt3cy
|
Why did the cavalry use the wedge formation?
|
Hi. I don't see any advantages of using this style of fight. The charge impact is significantly weaker than using line formation due to smaller area of attack. What was strong points in this method and what situation fit to using the wedge?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gpj1smg",
"gpj22lv",
"gpj345u"
],
"text": [
"A shield/pike wall's strength relied upon those in the front being able to focus their defense forward, with their rear protected by men ready to take their place in the wall, if someone fell. The key to defeating a wall was to break a hole through it, allowing the attackers to strike at the rear and sides of the defenders, rather than only at the front, where they were more-heavily defended. A cavalry charge often used a wedge formation to focus more power at a single point in the wall, rather than distributing it evenly. In that way, the cavalry was more likely to break through the line, shattering the defensive wall and leaving the defenders more vulnerable. Think of the wall as a concrete dam holding back water. If 50 guys with hammers each pick a spot on the wall and start hammering, it's going to take a lot longer to break through than if 50 guys all hammered at a single point.",
"It helps to break formation. The goal of a battle that isn’t a final stand isn’t to kill the most people, it’s to force the opposing army to retreat. Breaking the opposing formation disrupts lines of command, and individual foot soldiers, particularly in those days, did not have the tactical know how to maintain their positioning, which as you pointed out, could give them the advantage. Once the fight or flight of the individual monkey brains turns from fight to flight as they see an arrow of horses and men splitting them off from the rest of their unit, they’ll start to flee, and that’s all the opposing army needs",
"The concept behind the wedge formation is that it makes it easier for your opponent to move or be pushed away. If you attack in a line formation then it is easy for the opponent to be stopped when trying to step back out of line. However with the wedge formation you also allow them to step aside and not just back. So it is very effective at breaking through the line but much less effective at actually inflicting casualties. The wedge formation is therefore very situational and used as a tactical tool. It is often empolyed with cavalry because their most usable strength is often their mobility and by using the wedge formation they increase their mobility as they are able to break through shallow lines of infantry that might be deployed to stop them. Say for example a general wants some cavalry to go around the main enemy formations and attack the enemy artillery. However the artillery might have a line of infantry protecting them from just such an attack. So instead of attacking in a line formation and risk getting stuck inn with the infantry they can employ a wedge formation forcing the infantry to step aside letting the cavalry through. The infantry is then left as two or more scattered groups that requires some time to reorganize into a coherent group and then cross the battlefield to get to the aid of the artillery who is currently engaged with the cavalry. If the infantry is not able to reorganize in time for the cavalry to return then the cavalry can even ride circles around the infantry picking off any small groups as they ride past them. The wedge formation is of course not exclusive to cavalry. It is often used by infantry as well for the exact same purpuse. For example in modern police and security units the wedge formation is used a lot when they want to pass through a hostile crowd or splitting them up. The wedge formation is also used by units armed with guns, for example riflemen or tanks. However this have nothing to do with the classical tactics but is rather designed to allow the guns to support each other as they will have the best overlapping field of fire."
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[
"url"
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lwth5v
|
Is there a difference between a high end CPU running at 5GHZ and a low end (overclocked) CPU running the same speed? Without counting the obvious CORE count
|
Technology
|
explainlikeimfive
|
{
"a_id": [
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"text": [
"Your CPU is not only the clock speed. There are other factors, like cache size, PCIe version, drivers, and so on. If your CPU runs at 5GHz standard it is probably much newer and has not only a better clock speed, but is better any metric that determines its abilities. So it is not a given, that the high end CPU is better, but very probable.",
"There will still be some difference in some cases though not that drastic. High end and low end of the same architecture (i9 and i3 of the same generation) won't have much difference but modern processors can beat overclocked old processors on many tasks. First, 5 GHz means that the processor is doing 5 billion elementary operations per second but the set of these elementary operations can be different. Some stuff (like calculating a sum of two arrays or operating on very large numbers) can be done in a single tick on a modern processor while an old processor would need to split it into several ticks. Second, modern processors usually execute several operations at once because different operations are computed on different parts of the processor (adding two integers and multiplying two floats will utilize different parts of the core and if these operations are independent, they can be done simultaneously). The processors even try to predict what the \"if\" statement will end up with to start executing the next code branch ahead of time. Here, more capacity for simultaneous execution and more advanced prediction / reordering algorithms will help the processor work faster. Third, you cannot fit all data within the processor and reading it from memory is horribly slow compared to the processor speed. If a processor requested some data and cannot continue without it, it has to stall and wait until the data is delivered. Hence, processors have several levels of cache memory: increasingly smaller but faster memory sets which store some of the data that is constantly being used. Modern processors have larger and faster caches which will come in handy in some tasks.",
"If we're talking about two CPUs from the same manufacturer from the same generation... yes. The way they manufacture the processors, they make a big batch of hundreds of them all at once, and then thoroughly test them. The ones that perform 100% perfectly are packaged as high end CPUs, and the ones that have flaws have the faulty sections disabled and are sold as lower end CPUs. This means there are two different ways that the low end CPU can be worse than the high end one at the same clock speed: * The low end CPU will have less cores to work with, so it will not be able to do as many parallel (simultaneous) actions as the high end CPU. * The low end CPU is more likely to have sections that are slightly faulty but still usable. What this means is that the CPU may be fine at normal clock speeds but unstable at higher clock speeds, leading to crashing.",
"It depends. Are they exactly the same chip, but one's just clocked higher? Then yes, same performance. Here we get into chip manufacturing. When chips are made, they test them to see how good they are. One chip may successfully clock higher than another without going over the heat maximum, so they sell that at the high end, and the others at the low end. Trying to clock the low one higher will need lots of cooling because it didn't test out at the higher clock rate, and you may run into other issues. Back around 2000 AMD had the reverse issue. Their manufacturing was too good, and too many chips were testing at high clock rates, not leaving enough to sell for the low-end market. So they just capped some at a low rate with a resistor and sold them as low-end chips. People found you could fix that and run them fast with no issues. But if you're thinking an i5 vs. an i9, there are a lot of other differences between those chips than just clock rate that make the i9 faster."
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|
[
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[
"url"
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|
lwthpe
|
why is pure water an insulator?
|
I just saw a video of a guy placing electronic stuff in a tub of water saying water is an insulator. Why is that?
|
Physics
|
explainlikeimfive
|
{
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"text": [
"Pure water is an sort of an insulator because it has no ions. Water conducts electricity because of things like calcium and magnesium present in the water. Distilled or deionized water doesn’t have these ions to conduct the electricity. Tap water and natural water are not pure water, so don’t go mixing electricity with them.",
"What is conductive are the salts and minerals that are naturally dissolved in the water, not water itself",
"To transfer electricity you need charged particles that can move around. Metals are conductive because in a lump of metal atoms exchange electrons with each other and these electrons can move around. Pure chemical water consists of electrically neutral H2O molecules which don't transfer electricity. However, if you dissolve salts and other stuff in water, even in a small amount, salt will fall apart and turn into positive and negative charged ions which will transfer electricity."
],
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3
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|
[
"url"
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[
"url"
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lwttvb
|
What is the difference between Stack and Heap Memory?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gpj5axr"
],
"text": [
"The way things are added and removed is the main difference. Heap is like a pile of leaves where you can add leaves and remove them as needed. Stack memory is a FILO(First In Last Out) queue. It's like a can of Pringles. You can only take out the top chip. If you want to add chips you can only put them on top of the highest one."
],
"score": [
3
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|
[
"url"
] |
[
"url"
] |
|
lwua3m
|
when you get a cut internally, for example from an operation, what happens to it? Does it scab up like on your skin or does something else happen?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpjbnmn",
"gpj7c8i"
],
"text": [
"Surgeon here. The same process that happens on the outside happens on the inside: Platelets and proteins in the blood cause clots which help to \"seal' the area, and other cells come in over time to heal the wound. It doesn't take the same form as scabs due to the environment (basically it's wet), and the body breaks it down and absorbs it over time. The body also often forms adhesions (bands of tissue sticking nearby structures to each other)",
"Depends on where the cut is and how deep. Your muscles receive small lacerations everytime you do strenous motions and this is why they get bigger due to exercise. Larger cuts however can cause internal bleeding which doesn't heal as cleanly."
],
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43,
6
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"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
lwucqn
|
why does fanning two books together make it near impossible to break them apart?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gpj7x5i"
],
"text": [
"Friction is a function of surface area. That’s why a bowling ball with a very small contact patch slides around much easier than a book or wood plank that weighs less. When you interlace the pages of two books, you’re giving them an enormous amount of contact area. The front and back of every page is touching the other book, that can be dozens or hundreds of square feet of contact. Push down on the cover slightly to apply a force to all that surface area simultaneously and they’re impossible to separate."
],
"score": [
7
],
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|
[
"url"
] |
[
"url"
] |
|
lwucrx
|
Why can you sit 2 hours trying to solve a programming/math problem, give up, go to bed & then when you wake up, solve the problem in 10 minutes?
|
Other
|
explainlikeimfive
|
{
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"text": [
"When you keep trying to solve a problem for a long time you often get stuck in some dead-end area of thought which doesn’t lead to any solutions. After you’ve rested you often can take a different approach which leads to victory. And it might be fast, because really many such problems have rather simple solutions once you know them.",
"Lots of problems can be solved with a good night's sleep. It's hardwired into us. During sleep, the brain takes the day's events and decides what to store in memory. This is an evolutionary advantage because our ancestors could remember where the food was found. If you had been working on a problem, the brain assumes that it is important to your survival, so it makes attempts to solve that problem and store the solution in memory. There was a recent episode on PBS' Nova about this process. It monitored the brains of rats and showed how they tried to solve a previously unknown maze to get to food. Those that had slept after exposure to the maze performed much better than those who just kept trying without sleep. One of the other findings was that the very young and seniors should be taking short afternoon naps in order to increase their retention and to not worry about problems so much.",
"I always liked an analogy that my professor used in college: There is a little man who is responsible for retrieving information for you in your brain. When you go and ask for something, you try to tell him not only what you want but where he should look for it. The guy keeps looking and can't find what you want. Later, you stop worrying about it and he decides to look where he thinks it is and finds it immediately.",
"There is a great book on this subject and I think it is called Why We Sleep. One of the most fascinating things revealed was an experiment measuring brain activity. I may get details wrong but the concept is correct. The experiment was on awake monkeys. Scientists wanted to see how their brains responded to certain stimuli. As the story goes, someone forgot to shut off the recorder device one night and came back the next morning to a pile a data that exceeded data collected during waking hours. It opened a whole new area of study for scientists. Are brains are not inactive when we sleep, they are more active. Our brains process a days worth of input and the next morning usually results in more clarity regarding the previous days problems. I rely on the above phenomena for all tough problems. I will spend a day testing solutions for something, go to bed thinking about it as I fall asleep and wake up confident that I will have a new perspective that solves the issue at hand. Sometimes it takes 2 nights but I usually find an answer. This of course is worthless for emergency decisions that need an immediate answer but luckily, that scenario does not happen often.",
"By working on the same thing hours on end, you start presuming that you only have a complex problem and that alll simple solutions have already been tried. You go to sleep and start frrom the real beginning with extra awareness and suddenly, the solution sticks out. This is also why \"fresh eyes\" work so well. Sometimes it's not about stupid errors bit just that the bigger picture solves more.",
"I think this is an example of a general pattern of problem solving that also explains why you can sometimes magically solve problems the moment you try explaining the problem to somebody else: **You're benefiting from having to start over again.** In the time you distanced yourself from the problem, you \"lost your place\", and basically end up having to re-trace your trail of though to where you got before. Usually, if we're stuck on a problem and can't find the mistake in our thinking, it's when the mistake happened so far back that we already forgot about it. Forcing you to re-trace your steps makes you notice the mistake. I find a good way to do this deliberately is by trying to formalize my chain of reasoning to see if I can \"prove\" why my problem is impossible to solve. (Of course, such a proof usually fails - but the point is that in trying to make the proof rigorous, I can figure out what the error was.) It also works great for puzzle games!",
"Engineer here. Sounds like you described tunnel vision. You see it with chess players all the time. You get so focused on a certain solution that you fail to see the other, more sensible solutions. That’s why getting a second pair of eyes is so valuable. Or taking a good long break and doing something else. Most of my best solutions have come to me while binge watching Netflix or during a gym session.",
"A simple analogy is that \"you can't see the wood for the trees\", when my engineers get stuck on hard faults we send them back to the hotel to get some food and a few beers, next morning the issue is typically solved in the first hour",
"i think like this. for many many hours your thinking how do i unlock this lock! you are fixated on unlocking this lock.... you try every combination, spend hours. you wake up and realise, you can just climb over fence. You didnt see it before because you were obsessed with unlocking the lock once you free your mind out of what you are try to overcome and switch to what you are trying to achieve, you'll have more success."
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|
[
"url"
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[
"url"
] |
|
lwuhz4
|
Why do songs get stuck in our head? Also, why is it usually only a small part of the song that gets stuck?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gpjawq4"
],
"text": [
"From a study on involuntary musical imagery (INMI = earworms): > The results of the present work indicate that features of a song’s melodic structure, as well as measures of its popularity and recency, can be useful in predicting whether a song becomes INMI [ URL_0 ]( URL_0 ) Apparently it's at least somewhat correlated with being recent and popular. Which isn't surprising as hearing it all the time and memorizing it probably makes it stick even more, though I'm not sure they ultimately deciphered what makes a song stick in your head as otherwise you'd get those kinds of songs 24/7."
],
"score": [
6
],
"text_urls": [
[
"https://www.apa.org/pubs/journals/releases/aca-aca0000090.pdf"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
lwumac
|
How do reflexes...work?
|
Just the title, how does your body know what to do with these stimuli without the signals actually going past your brain?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpjfu4j",
"gpjga26",
"gpjc7xw"
],
"text": [
"Because your brain isn't everything - it's just one part of \"the central nervous system\", which includes the brain stem (this tends to do basic tasks like how to breathe and how to eat), the higher brain (which does most of the \"human-y\" bits like knowing how to do 2+2 and being angry about celebrities), and the spinal cord, which is both a big highway of information and a reflex processing centre. Reflex systems are a bit like wires in electronics. Imagine you have a computer, that does all the standard things a computer does. It also has lights on the box for style value, and it has a separate button you can press to change the light. That button doesn't have anything to do with the circuitry of the computer, it's just one switch on the case that has a wire connected to the LEDs. Flick the switch and the light turns on, switch it again and it turns off - and it'll do this even if the computer is broken, cos it's a really simple light switch system that's just part of the case. A reflex system is composed of three types of neurones - sensory neurones, which detect the stimulus; motor neurones, which tell muscles to contract; and relay neurones, which act as a bridge between the sensor and motor, and also something that allows the brain to override the signal if necessary. When the sensory neurone detects the stimulus (let's say the pain of touching a hot pan), it sends an electrical signal all the way up your arm and to its associated relay neurone in the spine. The relay neurone sees this message and as long as it's not also getting a message from the brain saying \"don't do the reflex\", it'll spontaneously send a new message into its associated motor neurone. The signal travels down the motor neuron all the way back down your arm, and at the end, it tells the muscles in your arm to pull back so that you stop touching the hot pan. There's almost no information processing actually going on here. Reflexes are pretty much completely automatic and they're pre-programmed to know what to do when they receive a signal.",
"Cranial reflexes (blinking, salivating etc) do go through the brain. Otherwise we have evolved so much that our spinal cord sort of \"knows\" what to do in dangerous situations and we don't really have the time to relay the information to the brain and get a response. So, a reflex isn't a thought out action as it obviously suggests, it's simply a mechanism evolved over time for survival. That's why it doesn't need to have any thinking or involvement of brain. Hope this helped :)",
"While the normal nerves rosponsible for communicating Basic actions are transmitting informatorom to your Brain with the speed of about. 260 miles/h the nerves ends inform Brain of emergencies ex. Burning yourself. To prevent skin damage. These are the nerves responsible for reflexes."
],
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|
[
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[
"url"
] |
lwumy2
|
If the universe is always expanding, shouldn't Andromeda be getting further away, not closer?
|
I read recently that in about 4 billion years they expect Andromeda to collide with the Milky Way, but if there was a single big bang, and there was a central point where it all started, then shouldn't everything that was blown outwards be getting further and further away from each other as time goes on, and not closer? Or could gravity still affect it from that kind of distance to change the outwards momentum and start drawing them together? Or could there have been multiple big bang's?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
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],
"text": [
"The expansion of the universe is approximately 72 kilometers per second per megaparsec. That is, in one second, what was formerly one megaparsec (3.08 * 10^(19)km) expands by 72km. Andromeda is approximately 778,000 parsecs away (less than one megaparsec). That means that the universe is expanding less than 72km/s between us. As long as Andromeda is moving towards us faster than that rate, it'll cover the extra distance that is being created faster than it is created. This means over time its distance to us gets lower.",
"Andromeda is so close to us (milky way) that gravitational pull outweighs the expansional nature of universe. It's just because one force is stronger than other in this case. Any more distant galaxy gravity is too weak to do anything. As an edit I will say that there is theory called big crunch that stipulates that with enough time whole universe is again pulled together thanks to gravity but this will take a long time."
],
"score": [
13,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
lwunei
|
Why do humans show teeth when happy, while every other animal shows teeth to threaten?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpjagv4",
"gpjcg9w"
],
"text": [
"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.",
"Mainly the only mammals that show their teeth when threatened are predators like big cats, dogs, wolves and so on. Which makes sense, they use it to kill prey. Humans aren't carnivorous predators. We are omnivores, our teeth are not at the center of intimidation. Instead we share similar traits to other animals when angry. Like broadening our shoulders to appear bigger. And roaring (or yelling) as a deterrent. Arguably we do show our teeth just not in the same way. Then there are reactions unique to humans like balling your first or trying to destroy someone financially. Humans broke away when we begin to stand up, use our thumbs and had the intelligence to find use in these abilities. We may share simular reasons for threats like fearing our lives, offspring being harmed etc. But the way we react can be significantly different than any other mammal. Tl;dr Humans are not animals that use thier teeth to survive like a lion or dog. So why would we use it to threaten others? We do use simular tactics to other mammals like yelling (roaring), appearing larger, and so on. But we do millions of things that most mammals don't do when angry because we have an advanced brain, thumbs, and can walk on two feet."
],
"score": [
9,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lwvjhf
|
Why are you always more tired throughout the day when you get an extra 1-2 hours sleep, compared to when you don’t, even if bedtime is unchanged?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpjk55z",
"gpje66q"
],
"text": [
"A lot of the fatigue that comes with \"over-sleeping\" is due to the fact that you generally don't make it through another full sleep cycle. When you wake up naturally for the first time, you have ended a sleep cycle but when you wake up and fall back asleep, you typically don't make it through another full cycle. As a result, you stay fatigued because your body was still trying to sleep but you decided to wake it up. Very common with waking up and hitting sleep on your alarms or setting a timer for 30min, etc. TLDR; You naturally wake up at end of sleep cycle. Hitting snooze doesn't actually get you better sleep and will make you more tired. You're better off getting up out of bed right away or you risk being tired all day",
"Everybody has a sweet spot in terms of how much sleep they need to function well - for some people 6hrs work great, others can't function without 8 whatever your number is, your body has a natural rhythm for any biological process and so sometimes, when you change this by adding more sleep, you can feel more tired and generally worse overall."
],
"score": [
8,
7
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lwvv1v
|
How do you track the value of a currency? How do you know how much is a dollar really worth?
|
How is it possible to know if the currency is weakening or strengthening? **I guess I want to know what's the reference line** because if you contrast it with other currencies, it'd be uncertain since the other grow or fall too.. is there something stable that we compare it to? For eg. If I were to know how USD has been performing over last 10 years, what would be a unit? Is it just based on how much a dollar can buy you in the US if yes then how do you scale it on the scale of an economy Sorry if it's too many questions..
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gpji5mb",
"gpjikcz"
],
"text": [
"It depends how you want to track it. If you want to track it in country over time (the value of a dollar today vs. the value of a dollar at some point in the past), you use the Consumer Price Index (CPI), where the price of a set basket of goods used by a large number of American households is tracked over time. This is done, in the US, by the Bureau of Labor Statistics if you really want to dig into it. The alternative, is, as you suggested, to compare it to other currencies. Typically, when you hear on the news that the dollar is weakening or strengthening, that's what they're referring to. This has more to do with import/export than anything else (unless you invest in the currency markets). If the relative value of a dollar drops in comparison to the euro, American import companies that sell European goods have to exchange more dollars to get the same number of euros to buy European goods to import, which means when you go to buy them, they cost more.",
"The value of a currency is relative to other currencies (for major currencies, some currencies are tied to others). One way to evaluate it is the Purchasing Power Parity, an example of this is the Big Mac index. If you google it, it will show you the relative price of Big Macs in each currency. That will help you get an idea of what your unit of currency can buy vs others. It’s obviously more complicated that that, involving supply and demand for the currency, monetary policy, and foreign direct investment, but your 5 so..."
],
"score": [
8,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
lwwpb3
|
Why does your tummy rumble and grumble when you are hungry?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpjku1u"
],
"text": [
"After the stomach finishes processing food, it cleans itself off the remains of the food stuck to the wall by rhytmic contractions. You can hear these contractions as this typical noise."
],
"score": [
10
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
lwwvlj
|
How do DNA in animals work?
|
How do DNA in animals work?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gpjn8r3"
],
"text": [
"Think about DNA kind of like a supermarket. There are a finite number of things present there and they are in specific places. You can go to any isle that you want or need something from and pull it off the shelf. Your body does this when it needs specific proteins for things. It goes to that specific isle (part of the DNA) and copies that part of the DNA to create a near mirror image called mRNA. This mirror image is then used to make proteins that those specific cells need to do its normal housekeeping functions. DNA is mostly in a looser form but when cells divide, they condense into those pictures you typically see when you google DNA. In this form, 1 whole set of chromosomes goes to the new daughter cells."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
lwwvnd
|
What colours are mirrors?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gpjmn9f",
"gpjmabr"
],
"text": [
"It depends on how well they are made. Precision optical mirrors, like you see in a professional telescope, are colorless in the part of the optical spectrum where they are used. They are often front reflective and very expensive. Cheap mirrors, like you brush your teeth in front of, are green from iron impurities in the glass they are made of. Look at the edge of a piece of glass and you'll see it. There is a market for \"low iron\" glass which is more clear, but not often for use in mirrors.",
"Ever so slightly green. If you faced two mirrors together then you’d see the reflections get slightly greener as it gets re-reflected"
],
"score": [
5,
4
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
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