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m9zsoo | Why does the body reject transplanted organs? | What is it about a transplanted organ that tells the body it's foreign and doesn't belong? | Biology | explainlikeimfive | {
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"Every cell in your body is covered with \"Human leukocyte antigens\" which is a crazy random protein that is different for basically everyone alive. The immune system looks for all sorts of things, but if it finds cells and they don't have the right HLA then it defaults to \"kill this thing\".",
"Think bout it like this: You live in a big house with like 10 other people who you know really well. One day, one of them starts behaving weird and you're kinda worried about them but you don't understand what's going on with them. Then, suddenly that person becomes \"normal\" again, but you feel something about them is just off. And then later you notice that they're not that person. It's another person impersonating them. Obviously you will boot the imposter out of your home right?? But if they just don't /can't leave (because of a lease perhaps?) , you and the other housemates would do everything you can to not come in contact/cooperate with them.",
"Every cell as little things on it that makes sure other cells can recognise them. These things are unique to everyone, kinda like our fingerprints. When your body gets cells with a different \"cellprint\" it assumes this is something that can make you sick and will destroy it. This helps with bacteria, viruses and parasites that causes us to be sick, but causes a problem when you get blood or an organ from someone else. This is why it's so important to \"match\" with the donar. The more similar these cellprints, the higher the change it will be successful, with blood type being the most commonly known. Even with a successful transplantation it will get rejected, it may just take longer, you'll also get medication which effects the immune system so it won't attack the new organ"
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m9zwo3 | How do entire cities or civilizations end up physically buried underground with modern people living obliviously above or nearby? | Earth Science | explainlikeimfive | {
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"There is many ways things can end up buried. The very simplest is that for most of human history there was no trash trucks taking things away so people just buried stuff a lot. Even building a new house the easiest thing to do with the old house was knock it over and push it in a hole. For natural processes there is lots of them. The best are very sudden, like a land slide or a giant flood that carries mud. Or even a volcano like in pompeii. But even without that think about what would happen if you made a big pile of dirt in your yard. Eventually the rain might make it go away. But it doesn't really go away, all that dirt just washes down hill, and if you are the guy at the bottom of the hill, if you don't sometimes clear all the dirt it'll eventually build up. very very slow, but eventually. Same with places that rocks break down into dust, that dust blows somewhere, and eventually would cover up the place it blows to. Most types of erosion wear stuff away one place then it piles up somewhere else."
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ma01bq | Why are medical pill capsules usually white and some other colour? Why aren't they just one colour? | Technology | explainlikeimfive | {
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"The color combos and imprints helps medical professionals identify and distinguish one medicine from another easily"
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ma01qg | If someone dies during a surgery, why the surgeons don't extract all of their blood and donate it to blood banks? | Biology | explainlikeimfive | {
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"One major reason is that people who are undergoing surgery are going to be pumped full of drugs. Vasodilators, vasoconstrictors, sedatives, antibiotics, all these things which are useful for the surgery but not something you want in donated blood. Also people who died are likely to have other serious problems with their blood, such as toxins their body was unable to filter out, infectious diseases, and general detritus from systemic organ failure. We can get plenty of donated blood that isn't contaminated by such things so there isn't any point.",
"Because if someone dies during surgery they're going to be chock full of anesthetics. And even so, they wouldn't be a certified donor. Becoming a blood donor is a somewhat extensive process and if you're not in good health and decease free you won't be allowed to donate. So even if they could extract all of the blood, which they can't, because the heart has stopped. It wouldn't be worth certifying a dead donor just for a single donation.",
"Ok, so, the blood isn't flowing, so trying to collect it before it clots would be impossible. If someone dies in surgery, there is a reason - often sepsis, that alone would make their blood useless. After death, the cells die quickly, releasing chemicals that would also make the blood useless for donation. As as others have said, all the anesthetic drugs mean it can't be used. Patients rarely actually die in the operating room, and usually when that happens it's due to massive infection or massive trauma. In the case of trauma, they've lost a lot of blood already - so they've likely been given blood. This messes with the ability of the blood to clot. If they live, it corrects. If they die, all those clotting factors are screwed up. Blood is a lot more complex than say, water in an irrigation system.",
"Really it comes down to permission. The same way you have to register to be an organ donor, you’re essentially giving them permission to harvest your organs. If the family of the deceased finds out that the medical professionals harvested your blood without permission, that family could easily sue the hospital for harvesting without permission."
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ma077n | If it’s bad for you to bottle up emotions like anger but it’s also bad for you to be angry all the time, what can you do to release some of that frustration in a healthy way? | Other | explainlikeimfive | {
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"Some methods include physical activity. Get a punching bag, or go to gym with one regularly. This helps relieve the stress which may be causing the anger issue. Another way is to try to talk it out. If you have no one you trust to do that with, try this. Get an empty chair in a private space where no one will hear or bother you and sit next to it. Now treat the chair as the person or thing you are most angry with and try to talk it out. Yell at them scream, whatever, just try to get it all out. These may help, but if you are angry all the time you need to consider seeing a therapist and having them help you work through any issues.",
"If you're angry all the time it's probably indicative of larger issues, like poor anger management. It's not good to bottle anger up, but the healthy way to deal with it is to learn strategies to calm yourself down and put things into perspective, rather than to just shout and scream a bunch.",
"Anger is a “secondary” emotion in that it’s what we feel instead of the more vulnerable feelings that trigger it. People often “feed” their anger in order to hold the tender feelings at bay. The advantage of doing that is that you “get” to avoid the tender and more vulnerable feelings. The disadvantage of feeding your anger is that it pushes others away, increases your stress levels and the hormone releases that cause damage to neurons in your brain.",
"I listen to music. Angry music. Very very loudly. I walk a lot. I write a lot. You have to express that anger somehow, without hurting anyone in the process. I have TONS of things I've written up, letters and rants and ventings that'll never ever be read by anyone else, but it feels good to get it out onto paper. Well, a digital equivalent anyways. But, yes. MUSIC. Angry music will help.",
"Running helps me burn through anger and access the more vulnerable primary feelings that triggered it. Sustained physical effort just helps shake things loose and get the processing started. Running is perfect for this because it’s an activity that doesn’t take skill or paying attention to really. Just pick a pace/effort level you can sustain for a few miles, after awhile you’ll start having runs where you forget you are even running until 5 or more miles in. It’s the best feeling.",
"Anger management. Using anger productively doesn't fix the underlying issue. While it's beneficial, it's not a long term solution. Anger management and therapy are what you should use that energy for."
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ma1hiq | Why do we get stimulated by watching porn? Do other animals get stimulated by watching others? | Biology | explainlikeimfive | {
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"Yes, other animals do experience rewards in their brain This was evidenced by a Duke study where monkeys would pay for porn. URL_0 This has also been done with pandas to try to get them to mate."
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ma29r6 | why does some plastic tupperware type containers still look & feel greasy after washing even with name brand soap (dawn, ajax ect.) | Other | explainlikeimfive | {
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"On a chemical/molecular level, plastics and oil/grease are very similar in structure and composition. So when a grease molecule comes up next to a plastic molecule, long sections of it fit neatly and stick together. (Think like long Lego blocks snapping together) Things like metal or ceramic are very different materials from grease, so the grease molecules only stick to the other surface on a few places here and there. This makes it easier for the surfaces to be separated when washed. Fun fact: When professional pastry chefs make egg white meringues, for the best fluffiness results there should not be even a hint of fat/grease in the egg whites. Hence, they do not use plastic or plastic-coated utensils to whip the egg-whites, since the utensils likely harbour traces of fat on their surfaces.",
"Plastic is solid but when you zoom in you can see that there are little gaps. Plastic comes in many different types with different materials. Grease can get into those gaps if it's left in these plastics for too long. It can work itself in so deep that using soap can't quite reach it to break it down, kinda like having a kernel stuck in your teeth even after you brush.",
"Anything acidic or corrosive can break down the smooth outer surfaces of plastic over time, this could be acidic foods like tomatoes (pasta sauce), fruit acid, bleach and other abrasive/corrosive cleaners and simply tough scrubbing with scouring sponges. Once the sealed coating of the plastic wears away then it allows the ingress of oil and as others have mentioned, oil and plastic are pretty similar at a molecular level, so it is easy for them to bond together. Cheaper containers (e.g dollar store, takeaway tubs you reuse) break down more quickly because of the quality of the materials and the finish, but even high-quality plastic kitchen wear will breakdown over time with enough exposure to acidic foods, corrosive cleaners, mechanical scrubbing and extreme heat/cold.",
"These answers above also explain why I can’t get marinara red out of my plastic stuff and have to toss it.",
"Lol why would name brand soap be any better?",
"Plastic is made from oil (basically, oil mixed with salt) so will bond with other oils in a process called \"polymerization\". There is an easy solution. Washing with a baking soda solution will remove the \"greasy\" feel, although this is not as effective if you've used your \"tupperware\" as a microwave container."
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ma2ebq | Why does most of the eye drops says "Use the solution within one month of opening" even when its expiry is after 2-3 years. | Chemistry | explainlikeimfive | {
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"It’s good unopened for 2-3 years. Once it’s opened and exposed to the outside air it greatly decreases its usable life",
"Once it's opened its no longer considered sterile. Bacteria can grow inside the jug and you don't want that in your eye.",
"Much like food products once something is opened and the sealed container is exposed to bacteria it can grow in the container/in the solution. Try to keep it as clean as possible. This is the reason you want to wash your hand before using the eye drops and don’t touch the container to your eye. Anything that can be done to reduce the risk of infection."
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ma2wdk | What causes procrastination and how should you deal with it? | Other | explainlikeimfive | {
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"Procrastination is often caused by anxiety over the difficulty, or perceived difficulty, of the task at hand; or over the perceived effects of performing it wrongly. A person believes that the task or its outcome will be unpleasant, and so they put it off for as long as possible. Often this can persist until external circumstances - deadlines, looming failure, etc - cause *\"not doing the task\"* to become more unpleasant than *\"doing the task\"* and so the person does the task in a hurry, at the last minute. This can be very stressful because of the external circumstances being so threatening and so close, which in turn validates and reinforces the original feeling that the task would be unpleasant. Breaking free? Well, there are a few options, but my personal method is to pick apart the task into pieces which are too simple to feel anxious over: * Anxious about an assignment? Break it into chunks and write a *super, ultra-rough draft* for each chunk and then work from there. * Anxious about making a phonecall? Write a full list of what you need to get from it, and contingency options to recover if things don't go as expected. * Too much on your plate and can't decide where to start? Write it all out, making sure you get out whatever's in your head, and then see where you can start. Work on things from the most accessible 'handhold' -- grab onto it and see what else becomes possible. Just getting a proper grasp of the task can get you moving with enough momentum to keep going."
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ma3n91 | - Since places like, say, Death Valley exist, where it is almost year 'round sunshine, why can't we put a bunch of solar panels out there in the middle of nowhere to help with generating electricity? | Other | explainlikeimfive | {
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"Those solar farms would help the surrounding areas, but the transmission of electricity over great distances is not sustainable. It would benefit the empty land around that area the most. It would not help the east coast, which uses the vast majority of the US electric grid.",
"Because storage and transporting generated power is not easy. Most power generation plants are fairly close to areas where they are used. The reason for this is internal resistances of the cables cause a loss in power generated, if the distance is to far you would lose a large amount of the power generated. Also power consumption is not consistent there would have to he some way to store what is generated causing and increase in price.",
"We can. The only problem with this is that transporting electricity comes at a cost. Some of the transported electricity is lost as heat due to the conductor's electrical resistance. The rest is lost through impedance: the air or ground acts like a capacitor that has to be recharged every time the voltage changes causing additional energy lost as heat. The first issue can be mitigated and the second avoided through high-voltage DC transmission. This is expensive to setup, but allows efficient long distance power transmission at a loss of only 3% per 1000km with current technology.",
"Death Valley is a bad place to put solar panels because solar panel efficiency drops by 0.38% for each degree celsius over 20 °C The average temperature in death valley in June is 44.3 °C or 24.3 degrees over 20. So the efficiency drop is 0.38\\*24.3= 9.2% Death valley is no warm in the summer because it gets a lot more sun in the surrounding area but because of how warm air gets trapped between the mountain ranges that surround it. So for the solar panel, a cooler with the same number of sunlight hours is better.",
"Like others have said, transport would be an issue, but there are even more issues that get in the way. Firstly, to produce enough power to make a big enough difference it would cost millions, perhaps billions... as not only would you need the solar panels themselves, you then also need to add in the workforce to construct them, clear the land, build some form of protection for them such as a compound. You would also need people to guard them all the time as there are always people who will try to strip and steal things like this no matter who it hurts. Then factor in the mantience costs over the years, as machines inevitably break down even if there isn't an outside force that does it. Now take into account that your average solar panel settup takes between 6-10 years to begin paying for itself. Add all that up, and you will be unlikely to find companies and backers willing to spend all that money without a relatively quick turn around."
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ma4up8 | Why are non-stimulants like Strattera less effective than stimulants like Ritalin and Adderall for ADD? | Chemistry | explainlikeimfive | {
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"This is where the dopamine hypothesis for ADHD starts to break down. As a little bit of background, Strattera was approved because the FDA was desperate for a non-stimulant medication for ADHD (I have some more background from a practitioner who was there when Strattera was undergoing FDA evaluation and the BS Eli Lilly pulled once it was approved). Anyway, the current hypothesis is that stimulants act as stimulants (i.e. cause stimulation) by increasing the concentration of dopamine, serotonin, and norepinephrine in the brain. So the theory was, let's use other things that increase those same neurotransmitters in the brain but aren't stimulants. Enter atomoxetine (Strattera), a failed antidepressant that some thought helped for ADHD (spoiler: it didn't). The proposed mechanism for atomoxetine was that it would increase the concentrations of norepinephrine and dopamine in the brain. One of the current theories of ADHD is that there is a deficiency in dopamine. However, it can't be that simple. Why? Look at atomoxetine. It increases dopamine selectively in the prefrontal cortex (the area of the brain some people think is the area that ADHD affects). Atomoxetine does not work well at all for ADHD. So what if we supplement with dopamine directly? You can't take dopamine as it is because it doesn't cross the blood-brain barrier, so you have to give L-DOPA (the precursor that gets converted to dopamine in the brain). That also doesn't treat ADHD at all. Let's move on to the stimulants. There are 2 forms of amphetamine (dextroamphetamine and levoamphetamine) and 4 kinds of methylphenidate (MPH) (dextro-threo-MPH, levo-threo-MPH, dextro-erythro-MPH, and levo-erythro-MPH). Of those 6, only dextroamphetamine and dextro-erythro-MPH treat ADHD effectively. What makes those special? We don't know. If you look at any package insert for any stimulant that is used for ADHD, you'll see the language \"the exact mode of therapeutic action in ADHD is unknown.\" Anybody who says they know how stimulants treat ADHD is either lying or misinformed. We know how stimulants act as stimulants, but we don't know how they treat ADHD. And it has to be something other than stimulation, otherwise all the forms of amphetamine and methylphenidate, plus cocaine, caffeine, MDMA, phentermine, etc. would be useful in treating ADHD. But they're not. And think about what happens when somebody with ADHD takes a stimulant medication at a therapeutic dose : they SLOW DOWN. For some people, stimulant medications help them SLEEP (!). I have my own theories about how stimulant meds work for ADHD but this post is too long already. So to answer your question: Strattera doesn't work as well as stimulants likely because its design was based on a faulty interpretation of how ADHD works. We don't know why some stimulants work, but we know that they do. Much of the pathophysiology of ADHD is still being uncovered, but be wary if anybody ever says \"oh, we just need more dopamine.\" It's almost certainly not that simple."
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ma4xx6 | So why aren’t we meant to drink water from the hot tap? Or can we? | Chemistry | explainlikeimfive | {
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"In some countries, notably England *in the past* water heaters were open tanks. When you heat up water inevitably some of it will evaporate into water vapor, which expands far more than water. Modern water heaters are designed to safely handle this pressure and even have emergency valves that will vent if the pressure gets too high. Back before that, though, there was no way to contain that pressure that was both safe and cheap, so...they didn't. The boilers had openings so no pressure could build up inside. Since the boilers were open to the environment, anything could potentially get into the water. Given that it's a nice, warm environment it was possible for bacteria to grow inside the tank. This made hot water somewhat unsafe to drink and was meant to be used only for external washing and the like. Since modern heaters are entirely closed, this risk doesn't exist. [Mostly] sterile, chlorinated water goes from the pipes to the water heater and stays clean. You *may*, however, find that hot tap water has a bad taste or contains more minerals because it sits in the heater for a while until you use it. That said, the cold water sits in the pipe for a while, too, so you may not notice any difference at all. If you live in the US or most Western nations and/or your cold tap water is considered safe to drink, you can almost certainly safely drink your hot tap water, too, as long as you don't live in a historical home that never bothered to update the water heater.",
"It depends, of you have a combi boiler then go for it. If you don't an your hot water sits in a tank for a while, best not to.",
"Whether it’s a combo boiler or not, heat and water generally causes some build up in the tank/coil, so steer clear of any hot water taps unless they’re the new fangled ones that are designed to dispense fresh boiling water."
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ma5bp0 | why do stich marks and some wounds never fully go away? | I have stitches on my finger and my lip along with a scar on the back of my left thumb, and several marks on my arms, all have been there for several years, why do they never fully go away? | Biology | explainlikeimfive | {
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"Think of your body as a house with an absent-minded homeowner who does do-it-yourself repairs. One day, the neighborhood kids hit a baseball directly through the front window, smashing one of the panels. The absent-minded homeowner never saved blueprints for the house or took pictures of it. For this damage the owner could figure out that the broken part was inside window and all they need is to patch it up and get some replacement glass. In this case, the wound on the house could be fully regenerated so the house looks the same afterwards. On another day, a drunk driver crashes their car through the front of the house, taking out the window and its frame entirely. Now, the first thing to do is to make sure the wound is sealed. You don't want things from inside the house from leaving and you don't want the outside critters or weather to come in. The homeowner throws everything they can to seal it but it's not enough. The homeowner has to call the specialists (doctors) to help seal the damage. The specialists have to add additional holes (wounds from sutures) to the house and pull it together (stitches) to help seal the house. This pulls the walls together so the overall wound is smaller and easier to seal by the homeowner. Remember that the homeowner doesn't have good memory or blueprints for the house. With the window knocked out, the homeowner doesn't realize they have to add one. The body only knows how to heal based on the healthy tissue around it. With the walls stretched together, it doesn't resemble any regular wall they're used to fixing. Better to just plaster it over and hope it's sealed. This is known as a scar. Scars form over wounds where the body doesn't know how to properly regenerate. They lack the normal functions of the tissue. For example, scarred skin doesn't have hair or sweat glands. Over time, the fibers in the scar will tighten, pulling the wound closed and reducing the appearance of the scar but some may remain in place forever."
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ma6oxv | When someone is “In Shock” what does that mean and why does this happen? | Biology | explainlikeimfive | {
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"\"Shock,\" in a medical context, refers to insufficient blood volume. Shock can be subdivided into four types, depending on what caused it: * *Hypovolemic* (low volume) shock is due to blood loss. * *Cardiogenic* (heart-created) shock, due to a heart attack or similar. * *Obstructive* shock happens when something poses a mechanical barrier, such as air buildup in the space around the lungs or fluid in the space around the heart. * *Distributive* shock means the blood can't get to where it needs to be, usually due to anaphylaxis (hence, anaphylactic **shock**), or certain drug overdoses.",
"Shock is inadequate perfusion of oxygen to the body's cells, and is a life threatening condition. It is characterized by: elevated heart rate elevated breathing rate low blood pressure pale, cool skin diaphoresis (sweating) dilated pupils There are many types and causes of shock, including hypovolemic shock (loss of blood), cardiogenic shock (heart problems), neurogenic shock (brain and spinal cord problems), obstructive shock (cardiopulmonary blood flow problem), aniphylactic shock (allergic reactions), psychogenic shock (psychological cause), septic shock (infections), etc. All of these causes involve different mechanisms, but all have the same thing in common, which is to impair proper delivery of oxygen throughout the body. Treatment involves maintaining a clear airway, making sure that the patient is breathing or adequately ventilated with supplemental oxygen, maintaining circulation (with CPR or fluid therapy as appropriate), preventing hypothermia / keeping the patient warm, and then treating the underlying condition.",
"Shock occurs when the organs of your body aren't able to be perfused adequately (e.g. aren't getting enough oxygen to them). This causes the organs to not operate properly and as shock progresses the organs become damaged and release harmful substances into the circulation that further worsen the shock state. Shock can occur due to a problem with the pipes (blood vessels), pump (heart) or fluid (blood volume). As others have mentioned below, hypovolaemic shock is often due to traumatic blood loss but it can also occur in patients who are severely dehydrated due to vomiting, diarrhoea or severe burns etc. Either way, blood volume isn't sufficient to circulate oxygen to essential organs. Cardiogenic shock occurs when the heart has been damaged in some way and isn't pumping the way it should (e.g. damage to heart muscle or coronary arteries from a heart attack). Blood volume is essentially normal, but the heart isn't adequately pumping it to where it needs to go. Obstructive shock occurs when their is a mechanical barrier in the heart or great blood vessels (e.g. pulmonary embolism or cardiac tamponade). Again, blood volume may be essentially normally, but it isn't being pumped to where it needs to go. Distributive shock occurs when the blood vessels become 'large and leaky'. This is common in anaphylaxis (severe allergic reaction) or septic shock (severe infection). You may still essentially have the same blood volume in the body but your 'pipes' have increased in size and have become more permeable so again it becomes harder for the body to get the blood circulated to where it needs to go. Another way you can think of shock - no matter what the cause - is as compensating, decompensating and irreversible. With compensating shock, the sympathetic nervous system (the 'fight' of fight or flight) kicks in by increasing heart rate, breathing rate, constricting blood vessels to keep blood pressure normal, shunting blood to essential organs in an attempt to keep the body going (among other things). If whatever caused the shock isn't treated in time, eventually the body can't compensate anymore so you will start to see a move into decompensating shock - a key symptom of this is when blood pressure starts to drop, the patient may start to become drowsy or confused... In irreversible shock, the damage has now become too severe to treat - heart rate drops, blood pressure drops, patient loses consciousness and will eventually die."
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ma6rgl | Why does the body not get used to chronic pain? | I get why feeling pain is important for us, but why does the body not get used to chronik pain? I dont need to get reminded that my knee hurts for 10 years. Wouldnt it be smarter if the brain is like: "This nerve is sending me constant signals about pain for years, i should just cut it off". | Biology | explainlikeimfive | {
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"A thought-- you never know about the chronic pain your body gets used to, by definition. A few years back, during and after an acid trip, I found my body \"remembered\" some old injuries and pain that hadn't been hurting for a long time. Similarly, I had a problem tooth pulled that I'd forgotten about, but after the surgery my whole neck and jaw felt much more *right*. I realized there had been chronic pain there even though I hadn't been consciously acknowledging it. I think we *do* get used to a lot of the chronic shitty things happening in our bodies. Edit-- sorry for using personal anecdotes, but pain is weird and personal and I'm not familiar with the actual science. Will delete if inappropriate.",
"The simple answer to why does it behave the way that it does is because the way it behaves conferred an evolutionary advantage. I'll speculate for you and say that organisms which don't feel pain in injured limbs are more likely to exacerbate their injury to the point where the limb becomes completely useless.",
"It can't do that. Cutting pain off would also remove your ability to feel things in those places. And that's very bad, because feeling pain is your body telling your brain something's wrong. You'd be injuring yourself all the time and not noticing. And then there are folks like me, who are in constant pain literally everywhere all the time. I wouldn't even be able to move. Ultimately, the benefits of being able to feel pain outweigh the negative aspects. Being in pain may be miserable, but not having pain can easily cause you to be harmed or even killed.",
"It does to a degree. I've suffered from abdominal pain since I was an infant. I've had relatively few headaches. I tolerate abdominal pain much better than I do headaches.",
"Chronic pain is often associated with an increased pain response called hyperalgesia. This is thought to be due to your brain and nervous system going into a state of persistent high-reactivity after experiencing pain. Once this happens, your body can actually perceive pain even when the initial insult is gone.",
"Pain is an alarm signal, something is wrong when there is pain. In chronic pain, the alarm signal is behaving correctly, there's often an injury or an inflammation or some structural cause which the alarm is going off to tell you about. Just, we can't fix the underlying cause sometimes. My guess would be it doesn't shut off because the actual system of pain to inform us of bad things happening isn't the thing misbehaving. Pain itself isn't a specific signal, it's an over or under sent along the nerve, or a disrupted signal, it's more a check of hey, this isn't doing the right thing. The check is a good thing, and beyond a nerve block is fulfilling the purpose of telling the body something is wrong, turning it off would be dangerous because injury can still occur to the impacted site, alarm system still needs to do it's job. But you can normalise chronic pain - I have chronic spinal headaches, spasticity pain, general nerve pain. It never goes away, even with my meds, but I can tolerate it for much much longer than when it first happened. The pain hasn't decreased, but my perception of it has changed due to signals like 'urgency' and 'fear' associated with normal pain being decreased. So some things do get turned off."
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ma6xnw | how does the brain repair itself due to stress & trauma? | Other | explainlikeimfive | {
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"Over time your body creates new cells to replace and refresh old and damaged ones. If the damage is extreme, more so than a little bit of recovery can handle, you might never be the same, but your brain will reroute processes through different brain cells just like it would if you were learning something for the first time."
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ma7g8s | How come knives can cut easily through fabric and food but not rock? | Physics | explainlikeimfive | {
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"text": [
"A knife is a tool that takes the force applies to it and focuses it along a very narrow edge. This concentrates the force in one place, and helps it to break the bonds holding the material you are cutting together. Those bonds have different strengths in different materials, making them correspondingly easier or harder to cut. If the material you are trying to cut is even stronger than the material that the knife is made of, then most of the force will wind up going towards deforming and wearing away the edge of the blade instead of cutting through the material."
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ma818h | why is hot air suffocating and cold air refreshing? | Biology | explainlikeimfive | {
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"grr62vc"
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"text": [
"Our body runs at an optimal temperature that it tries its best to regulate. Breathing plays a huge part in cooling. When breathing in warm air you are getting oxygen but your not getting the cooling effect your body relies on."
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4
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ma84y4 | What is an Adam’s apple? | And why do only biological men have them? | Biology | explainlikeimfive | {
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"grr009w"
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"text": [
"It's just a lump of cartilage around the vocal cords. It doesn't serve any biological function. Women have the same lump but it tends to be smaller and may not be noticeable through the skin."
],
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16
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ma8l1w | If heat makes things expand/less dense, why does heat make clothes shrink and thinks like plastic and styrofoam shrivel up? | Physics | explainlikeimfive | {
"a_id": [
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"text": [
"Something like foam shrinks when heated because it is melting. Before melting it should expand a bit just like everything else. Foam is not solid, it is porous (full of holes), and when it melts those holes close making it take up less space. The fibers in clothing probably do something similar.",
"I heard that the heat of the dryer is not what causes the shrinking so much as the tumbling action of the dryer. And things like plastic and especially styrofoam are products that have expanded and so added heat breaks them back down into what they are made from."
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ma9pn8 | Why does very hot water sometimes feel almost cold? | No idea what the flair for this would be so chemistry it is | Chemistry | explainlikeimfive | {
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"text": [
"You have both hot and cold temperature receptors. Obviously the hot receptors are activated but considering this is very hot water, your body is overstimulated considering the danger you're in. As a result, the cold receptors are also activated along with pain receptors."
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maao53 | Why can contact lenses be worn all day without issue, but nap with them in for an hour and they get glued to one's eyeballs and one's eyes get gunky. | Chemistry | explainlikeimfive | {
"a_id": [
"grrgfne",
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"text": [
"The eye is a self cleaning mechanism. That's what blinking and tears are all about. However, this mechanism is shut down during sleep, so your eyes stay shut. Contacts irritate the eye, but you can learn to tolerate it. However, without the cleaning mechanism, the irritation is much more painful.",
"Well you actually produce less tears when asleep. When you sleep your eyes are closed meaning that you simply don’t need to replace tears as they are lost through evaporation or being rubbed away. These tears also act as a lubricant for your contacts when your eye moves. During sleep we enter something called rem. Rapid eye movement sleep. As you can imagine a lack of lubrication and all this eye movement doesn’t do good for your eye. This causes irritation and thus the gunk as a defense mechanism against the irritant. In this case your contact lens."
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maap05 | If Black is when an object absorbs all the color and White reflects all the color. How about Grey, what colors does it absorb and reflect to show it being Grey? | Physics | explainlikeimfive | {
"a_id": [
"grres6l",
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"text": [
"Depending on the amount of grey, it will absorb a percentage of each colour of light, and reflect a percentage.",
"Colour isn't just whether or not light of any given wavelength is absorbed, it's also about how much of that wavelength is absorbed. When light hits a thing, there's a chance each photon will be absorbed or reflected, and that chance depends on the wavelength. If you have a bright red object for example, that might reflect 5% of green and blue wavelengths, but 90-95% of red wavelengths. There's still a lot of light being reflected, but its mostly red light. A dark red object meanwhile might reflect the same 5% of blue and green light, but only 25% of red light. It's still predominantly red, but there's a lot less total light being reflected, so on the whole it looks darker. With grey, you've got the same proportion of each wavelength being reflected, but the amount is varying - a pale grey might reflect 80% of each colour, where a dark grey only reflects 20%."
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mab7pw | How do YouTube & other social media/platforms store the massive amount of data uploaded to their site? Will they eventually run out of space? | YouTube gets 500 hours of content uploaded every minute. How do they manage to store all of this data? They can't do this forever, will they eventually run out of the resources to store it all? | Other | explainlikeimfive | {
"a_id": [
"grri3v9",
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"text": [
"They use both heavy compression and tons of storage. If they are having capacity issues, they buy more storage.",
"Compression and storage YouTube has plenty of processing power to work with so they spend time optimizing the compression for each video to fit it in the smallest storage space and to reduce the bandwidth needed to send it out later. You can expect another 3-10x reduction in file size from what you upload from your phone to what Youtube actually stores. Next is storage and Google has a truly massive amount of storage along with Amazon. Back in 2016 Google was estimated to have around 10 Exabytes (that's 1,000,000 Terabytes) but capacity grows exponentially and with 2019 having shipped ~800 EB of HDD capacity its far to assume Google is somewhere over 100 EB these days. So basically really good compression, and more spinning hard drives than you can really wrap your head around"
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madip0 | What makes smiling/laughing so contagious? All it takes is for someone else to smile at me and I automatically want to smile back | Biology | explainlikeimfive | {
"a_id": [
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"text": [
"We're pack animals that unconsciously try to connect to anything. Mirroring is a great way to build connections so without thinking we mirror those around us to try to build our \"pack\"",
"If you're asking about what's physically happening in the brain-- it starts with mirror neurons and then gets reinforced by positive feedback (Not an expert, but this is what I understand) Mirror neurons activate when we see someone doing something. So for example, if you saw someone toss a baseball, (especially if you'd never seen it before) the mirror neurons in your head would light up the parts of your brain that would light up as if YOU were trying to toss a ball. Additionally: for smiling specifically, you have been trained from birth to like smiling. Originally it was the mirror neurons that helped you figure out how to actually smile (babies are not born knowing how to do this) you mirrored what every face around you was doing at you, but smiling also became very strongly associated with positive rewards: closeness, family, food, warmth-all the stuff that helps us survive as a helpless infant. From there it is a feedback loop. ELI5: Our parents smiled at us, we smiled back at them; they loved it. They smiled back at us more! We loved it! We smile back at them more, they loved it even more! ect ect. Fast forward 25 years later, you and I are sitting at an outdoor cafe absolutely losing our minds because A DOG JUST SMILED AT US AND WE LOVED IT.",
"Empathy is a factor. Empathic people tend to be more susceptible to mimicking others. Psycho and sociopaths I expect find this tricky.",
"It's probably the remains of our animal herd days. The contagiousness of smiles even yawns and all that"
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maf076 | Why is a standard thermometer only legible from one specific viewing angle? | Technology | explainlikeimfive | {
"a_id": [
"grs2y7d"
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"text": [
"The actual mercury tube you see is very very thin. When you can see it, you are looking through a lens that makes the hair-width tube look much wider. Like any lens, it has a specific viewing angle."
],
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17
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maf8z2 | How are MAC addresses generated for virtual or physical network adapters? Do they have to be globally unique and not reusable? If so, how is that guaranteed? | There are many types of network adapters, many different manufacturers, all on potentially huge internetworks. Adapters get removed, changed, and added all the time. Is a guarantee of ARP that the link layer address is unique? If so, how is that uniqueness ensured at that layer? If it is ensured by the nature of MAC addresses themselves, how are those addresses generated or issued so there is no chance of collision? | Technology | explainlikeimfive | {
"a_id": [
"grs56in",
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"text": [
"For physical devices, the manufacturers are allocated ranges of MAC addresses and are responsible for setting the default network address to be different for each device they manufacture. It's possible to configure network devices to use a different MAC address, other than the default, and this is sometimes done so that routers can have multiple devices, each on a different network, all with the same MAC address. For virtual interfaces of the kind used to allow multiple IP addresses on the same network, there's still only one hardware ethernet device and the MAC address is the same for each IP address. Packets are allocated to the virtual interfaces according to their IP addresses. You talk about \"potentially huge internetworks\" but MAC addresses only need to be unique on the same Ethernet network (at what is known as layer 2). The Internet Protocol, with routers passing packets around the world, works above that at layer 3.",
"To add to what others have said, a MAC address is 48 bits, which is enough to handle everyone on Earth buying a new device with a new MAC address every week for 700 years. They are typically assigned to manufacturers by the IEEE in blocks of 24 bits (MA-L): that's 1.2 million blocks, each block useable for 1.2 million devices. It's unlikely that the namespace will be exhausted any time soon."
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mafit9 | How does Walmart send surveys to your email when you only provide them your name and phone number? | Technology | explainlikeimfive | {
"a_id": [
"grs5wvs",
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"text": [
"Youbgo to a data collecting company and buy the data on people you're trying to contact. Somewhere out there you must have filled out a form with your name and email together",
"Its the job of data collection and/or ad agencies to collaborate all your \"digital footprint\" into one giant cloud of data about you. When you sign up with Walmart they have your IP (and indirectly your actual computer address), your name and phone number (obviously), and from your IP a rough idea of location demographics. This is more than enough data to get every other piece of data you've input on the web at any point. And also several things you may have never input, like your sex and gender, your various lifestyle preferences, cat or dog person, tea or coffee, etc. etc. Depending on how careful you are, simply knowing your username and a rough idea of your life story is enough to find out all of this information (*sans IP, usually*), this is a technique called social hacking, and is the way a lot of \"hacks\" end up happening, which are not the result of you clicking/downloading something malicious. This is all assuming you didn't accept their cookies, which makes this entire process childs play. As one of these companies (that Walmart is working with) can have already given you their cookie, which is now accessible in addition to Walmart's, so all their data you've probably given them at some point is (in)directly attached to that Walmart one, potentially adding the phone number to that list if its not been added to your footprint already. Although if they comply with GDPR they're not allowed to directly give it to the other company."
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magw6q | why are clouds puffy and not just round? | Chemistry | explainlikeimfive | {
"a_id": [
"grsnyv3"
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"text": [
"For something to naturally form into a sphere there has to be some force pulling it into that shape. A sphere is the shape you get when all the stuff making it up wants to be equally close to the middle. Obviously not all of it can be in the middle so the rest piles up as close as it can get which forms a ball with uniform radius; a sphere. In stars and planets this is because of gravity, and in individual water droplets it's done by surface tension. A cloud doesn't have enough mass to have its own gravity, so that's out of the question, and it isn't formed out of a single huge drop of water so there's no surface tension either. This means there's no overall force making it uniformly round, so it just blobs in whatever shape it first forms in."
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mah2dz | Will our bodies be more affected by ilness if we were to continue wearing masks and then suddenly stop? | As stated in the title I was wondering how this exactly works. I havent been sick all year, usally it is minor but atleast 3 - 4 times a year. If we were to continue to wear masks will our bodies get a larger reaction to for example a cold if you haven't had one in a few years? | Biology | explainlikeimfive | {
"a_id": [
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"text": [
"Yes. Our bodies build up antibodies. If we aren't exposed to bacteria we have no way to fight them off. Which means if we are later exposed the effects are much more serious. Every time mankind migrated to a new area, disease was rampant through the native population because of this. Being too clean isn't a good thing. That doesn't mean to be a slob, but we require exposure to bacteria to keep our bodies in good health and capable of fighting off bacteria and viruses. URL_0"
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"https://www.dignityhealth.org/articles/hand-sanitizers-and-your-health-how-clean-is-too-clean"
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mah2ni | Why do bodies store fat if it can't actually use it later on? | People say that the reason bodies store fat is because later on, when food is scarce, your body can use that fat instead of food. BUT THAT'S FALSE! I did some research and people with a lot of fat don't take any longer to starve to death than people without. Apparently, energy stored in fat isn't usable by your body to fuel it. An alternative theory I've heard is that fat is stored for warmth, but as a skinny person, I don't think I'm any colder than my heavy peers. It's really hard to find any clear information on this because the articles are always just talking about losing weight. I don't care about losing weight! I want to know the biology of the situation. | Biology | explainlikeimfive | {
"a_id": [
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"text": [
"If you eat literally nothing then fat doesn't really help you much because you will develop vitamin and mineral deficiencies and those will kill you. But during times of famine people don't have literally nothing to eat. They have food, just not enough to survive on. So lets say you're a peasant in the middle ages. Your normal diet is likely a ~3,000 - 3,500 calorie diet that contains several times your daily requirement of most vitamins and minerals. Now pretend there is a famine. Your diet now consists of 1,000 calories per day. You're still getting more then enough vitamins and minerals to prevent a deficiency but you're not eating enough to survive. However, if you have 20 pounds of fat on you then you can survive those conditions for a month before your muscles start to waste. If you can reduce your level of physical activity then you can survive longer - say its the winter and you can live a more sedentary lifestyle that only requires 2,000 calories per day, now you can live for 2-3 months before losing any muscle mass. You can obviously survive even longer than that, you just start to lose muscle mass, though losing too much muscle mass means you die because you can no longer perform the work necessary to produce food. During times of famine people can still eek out high nutritional value, low calorie diets by eating things they wouldn't normally eat. Things such as rodents, insects, and semi-edible plants like grass don't provide much in the way of calories but have tons of vitamins and minerals. If you eat a rat's liver, brain, and bones you've had a nutritionally complete meal with sufficient vitamins and minerals to last you for the next week despite the fact that you probably only got a few hundred calories out of it. A fat person will be fine surviving on rat organs for the next month. A skinny person on the same diet will be in such poor shape after a week or two that they're no longer able to produce food on their own and so even if food conditions return to normal they'll still die because they don't have the strength to get food for themselves.",
"Fat is used as an energy reserve by the body. Fat only stores energy though, not nutrients, so you can't survive purely on body fat alone. You'd still need to get vitamins, proteins, minerals, etc.",
"I can't answer your whole question but I can tell you that I have recently gone from 230lbs to 171lbs and I feel the cold all the time now. I used to walk round all winter in t-shirts, and have bare feet in the house, but now I am wearing layers, coats, slippers in the house, gloves and hats when I go out, and extra blankets on the bed. So I would say that my blubber was keeping me warm.",
"Look up Ketosis. Your body changes from using glucose to turning your fat into fuel as Ketones"
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maha4h | What make a blanket warmer than others? | If all my blankets are at room temperature, why do some feel warmer to snuggle in than others? | Physics | explainlikeimfive | {
"a_id": [
"grsduh8"
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"text": [
"Blankets do not provide heat, like an electric heater. They provide insulation, so that the heat your body provides doesn't escape. So a blanket that is better at insulating will feel warmer, because it traps your warmth better. So thicker blankets will feel warmer, as will fluffy blankets, because they contain air, which is a very good insulator."
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mahcqb | What does Doc Hudson mean when he says “if you’re going hard enough left, you’ll find yourself turning right”? | Like, I know what drifting is and what it looks like. I just can’t picture how the quote makes sense. Does he mean that the back of your car swings right when you turn hard left? Because obviously if you’re drifting on a right turn you won’t cut left. I’m lost. | Other | explainlikeimfive | {
"a_id": [
"grsd36m",
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"text": [
"When drifting, you use opposite lock to stay in a drift. Turning the wrong way to drift the right way. He meant that",
"Imagine you are going to drift during a left turn. So once your tires start sliding, the back of your car is sliding to your right (which begins to point the car left into the turn). In that situation where the back tires are sliding if you keep turning left the back of the car will continue moving right and eventually you will spin out. To keep the car pointing into the turn you have to the WHEELS right to keep the CAR pointing in the correct direction until the rear tries grab the surface of the road again."
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majyo3 | Is there any limit for how powerful computers can get, as dictated by psysical laws as we understand them? | As the title says. As a follow up; is there any limit for how much information we can store digitally? | Technology | explainlikeimfive | {
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"Yes, but they are still far away. The main limits are in how small we can make the logic gates that the computer works on and how fast we can pass the signals between them. The speed of light is a fixed limit on the latter and while the signals in computers don't quite travel at the speed of light, it is close enough that we can't really improve all that much in that area. The thing with the logic gates getting smaller, at the moment relies on us making smaller and smaller transistors. This will have to end at some point. We may be able to replace semi-conductors with something that can be scaled down much more than that, but at some point we hit a point where nothing can go any smaller. There are ways to look at the entire universe and consider how much mass/energy there is and what the smallest amounts of energy and time there could be and try to use that to put an upper bound on what you could in theory compute if the entire universe was at your disposal. You could infer from that a fixed upper bound on what computing or information at all is theoretically possible. At the moment though we are still in the process of making our transistors a few nanometers smaller and don't yet have to worry about running out of universe to do our computing with.",
"Yes. The [Bekenstein Bound]( URL_2 ) tells us how much information can be in one place before forming a black hole. There is also [Bremermann's Limit]( URL_0 ) for the maximum possible computation speed. And the [Landauer Limit]( URL_1 ) which is a lower limit on the amount of energy required for computation.",
"Landauers principle places a minimum on how much energy is needed to perform a calculation The Holographic principle places a limit on how much information can be packed into a given volume. We generally accept these principles as true, but mostly in a 'It fits the patterns we see, but there is no direct empirical evidence for it' kind of way.",
"There are physical limits, like the size of transistors, which scientists continually attempt to break record for. And there are heating concerns when cramming more and more components into smaller spaces. But the upper limits of total computing power and storage space will always come down to space. We can technically make computers as large as we need them to be, increasing capabilities via brute force."
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makrmi | Why do we instinctually scream when in pain? | Biology | explainlikeimfive | {
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"text": [
"Humans aren't solitary creatures, we have always lived in packs which later became tribes. So, thanks to the evolution, we developed a method to instantly signal other pack members \"It's dangerous here, don't do what I just did\" and \"I need help, take me out of here\".",
"We developed that instinct before we developed language. It is the best and quickest way to communicate to other humans that we are in pain. That knowledge can be very important for survival in ancient times, which is why it became an instinct."
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mal21a | Why do we get nervous talking to crowds but not talking to one person? A crowd is just one person repeated many times. | Psychology | explainlikeimfive | {
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"text": [
"We do get nervous when speaking to one person. There's a number of ways they could find out we don't know what we're saying, or find a flaw in our reasoning. More people means there's more eyes scrutinizing how we look and move, and ears analysing what we say. There's more ways we can be \"discovered\"",
"Just a little bit off topic from your question but an interesting fact. A common technique to get over the fear of public speaking is to focus on individuals in the crowd. Many successful public speaker and charismatic people, you will notice, do this very often. A great example of this is Hugh jackman during interviews. When he gets asked a question from the crowd he makes strong eye contact with the person asking the question.",
"> A crowd is just one person repeated many times. Which means that if you do something silly there are more people to see it, and the consequences are bigger. There's more pressure to do well. It also means that it's much harder to judge people's reactions, because if it's just one person you can easily judge their facial expressions and body language and know how well you're doing. If it's 50 people then it's much harder to do that. Anxiety is just your brain warning you that something might go wrong (in people who don't have anxiety disorders, anyway). In this case, it's your brain warning you of social consequences if you mess up the speech.",
"I think in an innate fear of being separated from the tribe. Like, while your out the front it suddenly becomes you and then them. Your caveman brain just wants to get back into the herd so your safe.",
"Being in a crowd is more anonymous and allows an individual to say or do something that they wouldn't do on their own, so crowds can be less tolerant of a speaker than an individual is."
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malk5m | Why can’t recycling facilities wash out the recyclable containers? | Technology | explainlikeimfive | {
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"Recycling facilities need to deal with incoming waste that isn't properly sorted. Ask the general public to give you glass bottles and you will get banana peels and used diapers in there as well because a significant portion of people are just terrible. So they need to be sorted, and there isn't one magic machine or computer to do this. A few poor workers suit up in PPE to pick stuff out of a conveyor belt of waste. It isn't processed immediately so it may be sitting around for a while festering, and it can't just be hosed down because they are containers and so shield their contents. Of course once it is sorted properly it can be chipped into small pieces and washed easily, so being a little dirty isn't going to stop them recycling. But at that point those poor sorting workers have already had to deal with the putrid remains in the containers. Washing the containers makes their lives better, it isn't a requirement for recycling to work."
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man10y | When volcanoes erupt, does that mean that the core of earth is slowly running out of lava? | Earth Science | explainlikeimfive | {
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"No. Plenty of the crust is sinking down into the mantle and melting at undersea fault lines. It's just swirling pudding with a slightly hard top layer you live on.",
"Lava is just melted rock, so as long as the Earth's core remains hot, it can melt more rock. In theory, the Earth's core would eventually cool, and there would be more lava, but it's predicted that the Sun will expand and destroy the Earth before that happens.",
"No. Well, not for a very, very long time anyway. Volcanoes exist where the continental plates either slides parallel to each other (or one underneath the other; called subduction), or move apart from each other. They mostly occur in the 1st and 2nd alternative. An example of the 3rd alternative (divergent boundary) would be on Iceland, which is located where the Atlantic Ridge is. If a continental plate slides underneath another and down into the mantle, it will start melting. The warming will cause hot mass, liquids and gases to rise toward the surface, forming volcanoes. Subduction is therefore when part of the lithosphere is 'recycled'; it sinks down into the mantle, and volcanoes form partly from the heated remnants of the subducted plate. So you can say that magma therefore 'renews' itself. Question is then; will the Earth's interior run out of heat? Now, your question was about if the inner parts of the Earth will run out of lava. It won't, as the mass of Earth is constant (i.e. lava mass ejected will not 'escape' from Earth). The heat inside of the Earth is partly a remnant from when Earth formed 4.5 billion years ago, and also partly due to radioactive elements decaying, releasing energy in the process. This heat will not run out for a very, very long time, as the half-life of many of the radioactive elements, such as uranium, is several billion years (also that the amount of heavy elements in the mantle and core is much higher than in the crust). So as long as the heat that escapes the mantle is less than or equal to the heat produced by decay of radioactive elements, the Earth's interior will not run out of heat anytime soon. The Sun will probably turn into a Red Giant and swallow Earth before we have to worry about that."
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maoxqr | how does sharpness work at an atomical level. | Other | explainlikeimfive | {
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"Have you ever pushed your finger in a piece of cardboard? It's likely you won't pierce it easily. Try again with a toothpick, and you barely meet any resistance. Assuming you used the same hand both time, the strength applied should be similar. So why the difference? The reason is the surface where the force is applied to. The bigger the surface, the less force is applied for each mm² (or any other unit of surface). Applying a similar force to a smaller surface mean more force per unit of the surface. Well that's the basic for sharpness too. The \"sharper\" it is, the smaller the surface that is directly in contact with whatever you try to cut. As such, you can more easily break the material. Another thing to consider is that \"cutting\" unlike puncturing is also in part about \"ripping\". When you're pushing down on your blade, it's purely a matter of force over surface. But when you're sliding the blade as well, you also \"Tear\" the matter. Due to friction, the blade grip whatever you try to slice and pull on it. While the matter is similar, as it's also a matter of how large the surface being pulled is compared to the force applied, some material are stronger against pressure than they are against tearing and vice versa. TL:DR: \"Sharpness\" mean lower surface of contact, which help in both tearing and cutting.",
"Atoms in a solid attract each other with [intermolecular forces]( URL_1 ), basically electromagnetism / forces of attraction caused by electron-sharing between atoms (chemistry in general, ion bonds, covalent bonds, etc., is electromagnetic at its core). So cutting a material is trying to insert a wedge of another material, with stronger intermolecular forces, to rip apart the atoms of the first material. Steel cuts plastics for example. The forces that you can apply at the \"human\" level (or even with a hydraulic press) might need to be large, because in general a spoon of material has [10^20 ]( URL_2 )atoms in it, and even with minuscule forces between said atoms, it \"adds up\". [Sharpness]( URL_0 ) is trying to concentrate the pushing force that you can apply to the knife or instrument, onto as few atoms as possible for the material to be cut, in order to minimize the sum total of all the resisting intermolecular forces from the material's atoms.",
"Pretty sure nobody is cutting, slicing, or dicing any atoms apart with a physical knife. The mechanical cut with a knife could at most cut molecules, but at the atomic level you’d need to be accelerating and smashing them and/or just waiting for some sort of decay process. Stimulated emission I guess could be a way to “cut” or split an atom if you wanted to cut an atom apart but the knife used in question would have to be pretty exotic and not something you could pick up from Costco."
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maoymn | How do some medicines take effect as early as thirty minutes when digestion of regular food takes significantly longer? | Chemistry | explainlikeimfive | {
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"grtcxgy"
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"text": [
"Medicine is very specifically designed for our digestive system and for absorption into the blood stream at different rates. Some pills breakdown extremely quickly in the stomach and the medicine is absorbed quickly in the intestines, other pills are (intentionally) tougher to digest and release their medicine slowly over the course of hours. It has to do with the intent of the medicine, some you want the full \"hit\" very quickly, some you want to keep a stable level between doses."
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map7ok | Why is it better to get our nutrients / macros / vitamins from real food rather than from supplements? | I know “they are called supplements for a reason,” heard it a million times before, but that doesn’t explain anything. *Assuming money isn’t an issue, I don’t understand why exactly I shouldn’t just live on multivitamins and protein shakes with oatmeal. Why do we need real food exactly? | Biology | explainlikeimfive | {
"a_id": [
"grtfbcf",
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"A lot of food contains things that help with the bioavailability of said nutrient. You may be taking the same dosage of something in pill form, but absorb only 50% of it. If you got that through food, you would not only absorb a higher percentage, but you would also get the plethora of other minerals, vitamins & hormonal support that comes from eating nutritious food rather than just popping pills. This would be very independent depending on the exact example however. You would have to be more specific... like why is taking a B12 pill worse than eating a steak... something like that. Also, because fats are essential macronutrient. Yes, in theory they can be kept very low for dieting purposes but they are needed for hormonal support & for nutrients. So yes, your plausible diet of oatmeal & shakes, & vitamins could work... but it’s far from optimal. You will feel like dog shit and it’s not sustainable. I would encourage you to read into Stan Effereing’s work. He has a whole “shakes are for fakes” motto & goes into depth as to why these are his beliefs.",
"It's likely that we still don't know everything it would be advantageous to obtain from our food sources. Over time we discovered micronutrients that we call \"vitamins,\" but that doesn't mean we've discovered everything we should be getting in our diets. Therefore, a varied diet makes sure we get most or all of everything needed for our best health."
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mapas5 | What is the difference between diesel and gasoline? What happens if I put diesel in a gasoline engine? And vice versa? | Chemistry | explainlikeimfive | {
"a_id": [
"grtfn0k"
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"text": [
"Diesel engines use compression for combustion, gasoline use sparks. So the fuels wont work in each other's engines. Edit: This is ELI5, 5 year olds don't know about lubrication and injection systems and hydrocarbons, etc., so I was just being simple here by saying they don't work, which is true for 2 unmodified engines, trying to work on the others fuel."
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mapohr | Why do balls not get squished and destroyed when they are hit with a lot of force? | Biology | explainlikeimfive | {
"a_id": [
"grthf8o"
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"text": [
"They do if you hit them hard enough. You can Google \"rocket powered golf club\" for some fun videos. They don't normally get destroyed because they're built for it; a ball that can't survive the sport it was designed for is a bad ball. They do squish, a lot in some cases and far more than you can usually see because it happens so fast, but under normal use they just rebound. You have to hit it significantly harder/faster than designed to do permenant damage, or do it many (many many many) more times. You can see this relatively easily by using balls in the wrong setting...hit a soccer ball with a golf club (a golf club you don't like) a lot and it will fail prematurely. Give a playground beachball to a pro soccer team and it won't last long either."
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mapxqc | Why do all people born before 1957 don't need a measles shot? | Biology | explainlikeimfive | {
"a_id": [
"grti5j7"
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"text": [
"To my understanding, many individuals of that age may have already been exposed to measles at a young age and still have some leaned immunity from that exposure, this reducing the benefit of a vaccination against measles."
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maq77v | what is happening at the molecular level when a length of string (or presumably more simply monofilament fishing line) is stretched to the the point of breaking? | Physics | explainlikeimfive | {
"a_id": [
"grtkyap"
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"text": [
"The molecules are sliding over each other. Monofilament line is made of polymers, very long molecules made of repeating units like a chain made of links. Polymers that are good for making fibers tend to stick to each other, like a bunch of strands of spaghetti with glue between them. As you pull and stretch, the polymers are aligning and sliding over each other, breaking and reforming bonds. This takes energy, which is why you have to keep pulling harder. Eventually the fiber gets thin enough that the remaining molecules and inter-molecular bonds aren't strong enough to resist the force and the molecules pull apart."
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maqdum | How are integrated circuits made? And what are they made of? | I understand what integrated circuits do (equivalent of alot of transistors) , but what are they made of to be able to do that? They're clearly not a bunch of miniature transistors ,they're a single solid piece from what it seems. I understand that they're made of silicone with a specific chemical composition that only lets in a specific voltage and is off otherwise but is it just one solid piece of that specific silicone? Is it like parts of silicone combined? Are there miniature wires going throughout? | Technology | explainlikeimfive | {
"a_id": [
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"They are one solid piece but it's not all the same material. The base material is silicon but, during the manufacturing process, a whole bunch of layers are put down. This can include insulators, metal (which acts like tiny wires), and \"dopants\" (extra elements that alter the silicon's electrical properties to have extra electrons or not enough). There are also manufacturing steps that will etch away parts of a prior layer to allow connections to lower layers. By very carefully controlling which layers are put down in what order, you build up a 3D solid structure of different types of silicon, insulators, and wires. If it sounds insanely complicated, you're underestimating it. Modern semiconductor manufacturing is, by a fairly significant margin, the most complex manufacturing process ever devised by the human race."
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maqh1x | Why are my hands and feet usually always freezing? They don’t necessarily feel cold, but if I touch my arm with my hand they feel like ice. | Biology | explainlikeimfive | {
"a_id": [
"grtmb5t"
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"text": [
"It could be Reynaud's syndrome. Usually hands, feets, toes and fingers changes from its normal color to a whitish or bluish hue also. [ URL_0 ]( URL_0 )"
],
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3
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"https://www.health.harvard.edu/blog/cold-hands-raynauds-201412037567"
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maqjhl | How exactly does one die from exsanguination? Is it loss of oxygenated blood to your body parts? Accumulation of toxins and CO2? Or is it brain death followed by body death? | Biology | explainlikeimfive | {
"a_id": [
"grtmb5o"
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"text": [
"You die of shock. Without blood your cells no longer receive enough oxygen or get rid of CO2. Their energy reactions shut down, CO2 builds up to toxic levels, and they die. Your brain is uniquely sensitive to oxygen deprivation so, typically, you're going to suffer brain damage before other parts of your body are irreversibly damaged but it's all going to die, it's just on different time scales."
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masbo1 | Are we in control of our whole body or just the brain? | Biology | explainlikeimfive | {
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"This is more of a philosophical question than a biological one. Biologically, the brain sends signals to the rest of the body on how to behave. Those other areas receive the signals and act accordingly (unless the signal cannot be received - as could be the case with an amputated limb). Whether 'we' are our bodies, just a part of them (the brain), or something else entirely, is still under philosophical debate. Are people actually a \"soul\" or \"spirit\" or are they completely physical? Would I still be \"me\" if my brain could be transplanted into another body? Does my body make up part of who I am as a person or is it just a container?",
"That's the hard problem of consciousness, and the answer is \"we don't know, and humankind may never know\" And you're putting too much stock in the brain. Reflexes (ie, removing your hand if you accidentally put it under scolding hot water) don't go through the brain at all.",
"What do you mean \"we\"? The Brain does a bunch of things, and chemical systems do a bunch of things, and some of those things are consciously controlled. If you define \"we\" to be our perception of our self, consciousness, then as far pack as Descartes it's been \"I think, therefore I am\". What we \"see\" is not an image from our eye sensors, it's an idea in our brain that stimulated by signals from the eyes. That's how you can see what's happening when you dream and your eyes are shut (plus, hint, dreams are not real)."
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masm7f | Why do we "feel" pain when seeing someone get hurt? | Other | explainlikeimfive | {
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"Mirror neurons. A special kind of neuron that fires when something is observed, so you feel it too.",
"**Answer for a 5yo** Pain isn't just physical, it's also an emotion we feel. It's not really the thing that happens to your body that's painful. It's whether or not we *feel* like that thing hurts or not. But when we \"feel\" another person's pain, we think that it's because [we're imagining]( URL_1 ) what they might be feeling, not because we're feeling it ourselves. **Answer for a 5th grader** Getting injured isn't really what's painful, it's our interpretation of the signal sent to our brain: that's what we feel like is painful or not. So, pain is both physical and emotional. When we get injured or something's swollen, the things that make up our nerves, called neurons, get switched on. They convert the physical sensation into electricity, which then travel through our nervous system, up through the rear half, or \"dorsal,\" part of our spine to a big bunch of neurons, which are called \"ganglia.\" Scientists call that group of neurons the \"dorsal root ganglia.\" And if the electrical signal there is strong enough, then the positive/negative polarity of the electricity changes, and our brain notices. If not, then it doesn't. This is because of what's called the \"all or none\" principle, and it shows up in other places too. For example, today, when you connect a high-definition antenna to a TV, you'll see a picture if the signal is strong enough, or a black screen if it's not. But back in the day, TV antennas weren't digital, so you'd see a picture if the channel's signal was strong. But the weaker the signal was, the more static you'd see. And if the signal was really weak, all you'd see would be static. Our nervous system works like a digital TV - on or off - but our emotions work like an old-fashioned TV: they're a more-versus-less kind of thing. That's why if both you and I had the exact same injury happen to us, you may not feel like it was particularly painful, but I might. But when people say they \"feel\" pain when seeing other people in pain, the same kind of thing doesn't seem to be going on. Instead, what seems to be happening is that we're *imagining* what their thoughts and intentions are like. **Bonus** Some people can be in pain for a really, really long time, so scientists are trying to figure out how to help them out. They're experimenting with turning off that \"digital switch\" in people’s dorsal root ganglia. And so far, at least in mice, [it seems to be working]( URL_0 ). It would be terrific if someday they can get it to work in people too, especially because some people get addicted to the medicine that doctors use to treat this kind of \"chronic\" pain. Even though the medicine is usually safe when doctors use it on us, when some people get home, they take too much and can get really sick and even die. So, having a way for doctors not to even have to prescribe those kinds of medicines in the first place would be really great. *Edited to answer the question that was asked, rather than just how we experience our own pain.*",
"The part in our brain regulating pain or empathy is triggered, sending us a signal that A) what happened to the person is bad and we want to avoid it for ourselves, and B) if its one we love, it can directly hurt us even more. Some people with conditions such as psychopathy or sadism (the latter not being a condition, although its debatable) might not feel anything or might even feel pleasure when witnessing someone else in pain.",
"The podcast \"every little thing\" has an episode about this URL_0 my recollection is that it's sympathy pain"
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masykk | Why does a feather fall at the same speed as a hammer in a vacuum created on earth? | Earth Science | explainlikeimfive | {
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"Because acceleration due to gravity is the same for all objects. The only reason a feature falls slower outside of a vacuum is because it has much larger surface area compared to mass, which allows the air particles floating around in the atmosphere to get in the way of the falling feather and slow it down more than they do something like a hammer (which has a much *higher* mass compared to its surface area).",
"Everything wants to fall at the same speed. However, air tries to slow things down when they're falling. The shape of a feather means that air can slow it down a lot more than the bowling ball, but in a vacuum there's no air to slow either down.",
"Absent an atmosphere, there is no drag to slow down a falling object. That means the only force to consider is gravity. Let’s say the hammer is one thousand times more massive than the feather. The hammer experiences 1000x more gravitational force than the feather, but the feather is also 1000x easier to accelerate. These factors offset perfectly such that each object is accelerated equally.",
"Because acceleration due to gravity is constant. No matter what, everything near the earth surface falls towards the earth with the same acceleration from gravity, 9.8m/s^2 or 32.2 ft/s^2. The reason some things in normal life fall slower is because of air resistance. Take the fluffy feather, normally the air it’s falling through gets caught up in the feather and the feather acts like a kind of parachute. But when you remove all the air, there’s no air resistance, and the feather will fall just like a bowling ball."
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mav1ba | How does technology, generally, become more affordable as time goes on? | I’ve seen people talk about how the technology for any given item isn’t affordable for mass production yet, but I’ve never understood what difference time makes to change that. | Technology | explainlikeimfive | {
"a_id": [
"grucg5k"
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"text": [
"Supply chains become more efficient and stable, process for manufacturing again become more capable, stable and efficient. Supply meets or exceeds demand etc. Many things play into the lowering of technology costs."
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7
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maviao | How does kidnapping insurance work exactly? | Economics | explainlikeimfive | {
"a_id": [
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"text": [
"Same way as medical insurance but with kidnappings. Medical emergency happens, you get a bill for 500,000 dollars, but yay! You have insurance that you pay for and the insurance covers it! Kidnapping (or other crises, sometimes including other violent crimes, depending on the plan) emergency happens, you get a ransom note, “pay us 500,000 dollars”. But you don’t have 500,000 dollars on hand, but yay! You have kidnapping/extortion insurance, and they step in to help. Same premise, just for a different kind of emergency."
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maw5nr | Why do travel agents call sales agents of travel companies to have them make reservations they are paid to make? | Other | explainlikeimfive | {
"a_id": [
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"text": [
"A travel agent is paid to figure out the best way to achieve the trip; that might include making the reservations themselves \\*or\\* it might include them contacting someone else. They might have special rates or agreements with the travel company that you can't see on their website, they'd need to talk to an actual person to get that. They might want to negotiate, you can't negotiate with a website. They might be trying to figure out if there's a different/better way to achieve whatever their customer is trying to achieve, you need to talk to a person for that. They might be trying to use a credit from past travel that you can't just put in like a credit card. And B2B travel contracts can be \\*complicated\\*. A lot of websites can't handle all those nuances, you need a person. My own company has a mammoth Concur travel front end but, in the back, it's travel agents calling airlines to actually get our negotiated corporate rates and perks."
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mawiw5 | physical media for movies has changed over the years. From VHS to DVDs to Blu-Rays it seems like they are constantly upgrading. Why haven’t music CDs done the same? Changing formats for better sound quality. | Technology | explainlikeimfive | {
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"They have. First there was vinyl records, then we had 8 track cassettes, then we had tape cassettes, then we had cds, now we're working with digital formats only. The only real difference is that in music has occasionally been more of a factor in making the upgrades. vinyl records actually have really great sound quality but it's really hard to put a record player in your car.",
"CDs have reached a quality where any further improvements to ound quality are physically imperceptible to human senses - and besides, music is now usually distributed over the internet anyways. Selling products on physical media is a legacy solution - in fact optical drives of any kind are becoming rare to see on computers and forget about the idea of them on smartphones which are the most popular music listening platform nowadays.",
"There were attempts--DVD-Audio and Super Audio CD. But nobody could really tell the difference, at least in terms of basic stereo that people actually listen to. DVD-Audio, at least, did allow for better 5.1 music, but nobody really cares about that for typical music consumption. Then downloads came and blew it all away anyway, and it turns out people were more than fine with compressed-to-hell MP3s from Napster.",
"The format of the CD was chosen to be able to encode all sounds that could possibly be detected by any humans. So the CD is already on the limit of what is the best possible sound quality. You could make it better but it would be a medical miracle if you could hear the difference. There were actually a format war for high quality audio disks in the 2000s between SACD and DVD-A. Both were based on similar technology to DVD. These both provided higher quality, longer playtime and surround sound. The problem was however that for most consumers they did not provide any benefit, so both lost the format war as people were content with CDs. There were actually several independent tests of these formats showing no difference in the quality between them. People could not hear any difference between CDs and these new high quality sound formats.",
"Because they already sound great, there’s really not much more quality you can have, and even if you had a 100% perfect recording, I’d guess 99% of people won’t be able to tell the difference between that and a regular CD",
"Once we moved on to a digital format, it just quickly became way easier to shuffle files around. [There are a few high-resolution physical formats]( URL_0 ) but they never really took off in the normal consumer space, because they were expensive, and mp3/portable file format players and the like were taking off at the same time. Anything higher resolution than a CD @ 44.1 kHz/16-bit is going to require a significant investment in hardware, and even then MOST people aren't going to notice a difference.",
"CD quality is seen as the pinnacle. That same quaility is available via online or streaming platforms, IF you allow the highest quality or download the content. It’s just often not by default so people don’t burn through their data cap. With video, it’s not really the audio piece that’s gotten better, but the actual video. As video quality gets better it takes up more space, so they developed new formats that holds more data. The only caveat with the audio aspect is you can add additional audio channels since you have more space. Ie, a vhs tape has stereo audio, while dvds have 5.1, Blu-ray’s have 7.1 and beyond available if they choose to add those features."
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mayc52 | If light is made of photons and if photons are particles, how can it pass through glass or any medium?? | Physics | explainlikeimfive | {
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"Although particles (sort of), photons are *massless*, so the only thing that really prevents them from passing through solid objects is if they get absorbed by an electron along the way. Electrons can only absorb specific amounts (called *quanta*) of energy, so they only absorb photons that contain that same amount. For transparent objects like glass, the specific quanta that their electrons absorb are outside the range of visible light; therefore any visible light passes straight through. The amount of energy a photon contains is related to its *wavelength* (because photons are also waves, for... reasons). Visible light photons have wavelengths between 400 and 700 nanometers.",
"There seems to be two different misconceptions at play here, so I'll try to address each one separately. Firstly with regards to light photons being particles, this is (roughly) half right. We are nowhere close to fully understanding the details, but light acts as both waves and particles in different situations. We call it Wave Particle Duality. So the fact that light can pass through otherwise solid objects is an example of it exhibiting wave like behaviour. The second is the idea that particles can't pass through a \"medium\". Perhaps you've just used the wrong word; but air is a medium and particles of stuff pass through it all the time. Gold foil is also a medium, and alpha particles can pass through that. Most of everything is completely empty space. Solids and liquids only block stuff by sheer density of particles packed into a small space; but gases have huge (in atomic terms) spaces between particles."
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mayk1m | : Why is it so hard to reintroduce nutrients to farmable topsoil? | This concept has been in the media for a while, our farmable topsoil is losing its nutrients. I've heard the factoid that our farmable lands only have 30 harvests left. My question is, why is it so difficult to reinfuse nutrients to soil? | Biology | explainlikeimfive | {
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"The issue isn’t the nutrients the issue is the top soil is literally gone from erosion due to heavy plowing, bad rotation, etc. What’s left behind is sand and clay, which can’t hold nutrients because there isn’t organic matter left.",
"It's not that difficult. Changing farmers ways is the hard part. The problem is with single crop agri-business farming, pesticides and non-rotated crops. These farms can reduce topsoil nutrients used by specific crops like soybeans, corn, and cotton. Increased artificial fertilizers only replace part of the nutrients. More and more artificial fertilizer is needed to keep up production, adding expense, possibly reducing yield. The difficulty lies in the fact that real soil is full of living micro-organisms that replenish soil nutrition. These can be killed by pesticides and a lack of crop diversity. New plowing techniques, crop rotation and new ideas about pesticides and fertilizers are solving these problems. The idea of failing soils is basically true and has been a problem since farming began. New ideas and techniques are solving the problem. Many farmers are working on this fascinating and encouraging study."
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mayu9n | How can a snowflake be different than any snowflake in existence? | Earth Science | explainlikeimfive | {
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"Because there's more combinations of how water atoms can join each other in a snowflake than atoms in the universe. If you have something like 10^20 atoms in a snowflake, what are the chances that all 10^20 atoms are going to be in the exact same position as a different 10^20 atoms that make up another snowflake? Very, very small. Infinitesimally small. So small the chances of it happening in this universe are effectively zero."
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mayx51 | How does the human nose work? Does smelling a dangerous substance (from a distance) mean we are risking our health to some extent? | Biology | explainlikeimfive | {
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"Yes. Distance reduces the concentration by some amount depending on the air flow but you are still breathing a dangerous substance. The damage done depends on how dangerous the substance is. For example, chlorine at high concentration will kill you. At some lower concentration it may only chemically burn your lungs. Lower yet and you may only get a sore throat. Even lower and you may only smell it like at the laundry. It's a continuous scale.",
"**Does smelling a dangerous substance (from a distance) mean we are risking our health to some extent?** Not necessarily. Luling, Texas is in the middle of a huge oil patch and stinks of hydrogen sulfide, which in any concentration is deadly. The entire town and surrounding area smells like this and has for decades upon decades and nobody has ever waved a flag as to health issues. On the other hand, there are certain chemicals that are extremely noticeable upon the first whiff, (like the residue after an arc in hydrogen hexafloride gas...smells like rotten eggs) but instantly deaden the sense of smell, so that the victim no longer realizes they're in danger.",
"Luckily, the amount required to smell something is usually much, much lower than the amount required for it to hurt you. There are a few notable exceptions though. You wouldn't want to know what VX nerve gas smells like for instance. But nothing you're likely to encounter outside an organic chemistry lab or a chemical weapons facility.",
"Depends on the substance. Each substance has a odor threshold (how much there has to be to smell it) and a danger threshold (how much will harm you). If the former is very low compared to the latter (e.g. chlorine), it's pretty safe to smell. If it's the other way around (e.g. hydrazine), you should GTFO as soon as you smell it."
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maz03k | In the most common isotope of hydrogen, it has no neutrons. That would leave 1 proton and 1 electron in the atom. So how does the electron stay in orbit if there are no other electrons to repel from when it tries to get ti the proton??? | Electrons stay in orbit because other electrons are trying to get to the protons, but when they try, they repel from each other so stay in an orbit, right?? But in hydrogen, there's only one electron so there are no other electrons to repel from when trying to get to the proton. So how does that electron stay in orbit and not go to the proton?? Thanks :) | Chemistry | explainlikeimfive | {
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"First of all, this is a really good question, which puzzled scientists for a long time and was major problem for the atom model, until Quantum Physics saved the day. And that not only for atoms with a single electron. Even if there are multiple electrons, one would expect them to fall into the nucleus one by one, attracted by its opposite charge. Nobody ever believed that they would keep each other away from the nucleus: someone would win the race and get there. The wrong idea was the same as a planet orbiting around its sun. After all, the planet is attracted toward the sun too (by gravity), but it does not fall into it... Well, not immediately. However, because of frictions, a planet does spiral toward its sun and eventually falls into it. This can be understood as the planet slowly losing (gravitational) energy, which is dissipated into heat. What's worst, once in the sun there's no coming back: no way to regain that dissipated energy. Only, for planets, energy loss (e.g, friction from space dust) is so small, and the initial energy is so big, that the planet will stay in orbit basically unaffected for much longer than the sun lives anyway. But for the atom, it's a different story. You don't even need space dust to lose some energy. Any charge moving (such as electrons) produces electromagnetic radiation (light) which costs a bit of energy and makes energy go down, bit by bit. The electron should then be spiralling toward the nucleus, and once all energy is spent, the electron should be in the nucleus, and never come back. By everyone's calculations, this should be very quick and atoms shouldn't last milliseconds. How atoms lived for billions and billions years, instead, was a complete mystery. The answer turned out to be... really strange. Turns out, at small scales you cannot just \"lose a bit of energy\". Energy comes in tiny packets, called quantums, and either you have one full quantum or none, with nothing in between. You cannot have half a quantum. It's like having one-cent coins, but no \"half-a-cent coin\". So you can have 50 cents or 51 cents but never 50.5 cents, or 50.9 cents. At atomic scales, energy of an electron is so small, that it cannot actually be lost \"bit by bit\". Either a full quantum of energy is spent, or none. When an electron has only its \"last cent\" of energy left, it can never spend it in part, so it does not spend it at all, ever (to \"buy\" electomagnetic radiation), and so it never falls into the nucleus.",
"Electrons have orbital angular momentum which keeps them distant from the nucleus, you can think of it like a planet around the sun (though physically it’s very different), the only thing stopping a planet going into the sun is it’s angular momentum. Also due to quantum mechanics electrons can’t have any value of angular momentum, angular momentum is actually quantised and the ground state (lowest energy) an electron can have has a non 0 angular momentum. That said electrons aren’t really point like particles and they don’t whizz around the nucleus in orbits like a planet, they exist spread out throughout space according to their wave function and only exist in a single point when measured , the ground state orbital actually extends into the nucleus so when you measure an electrons position there is a non zero chance of it being in the nucleus."
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maz1kp | How does data travel through a wire in for example a computer? | Technology | explainlikeimfive | {
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"Just like you can send messages to another person with dots and dashes (morse code) a computer can send data in 1s and 0s. Each combination of ones and zeros corresponds to a letter, number, or another character. The ones and zeros in the wire itself are just pulses of electricity. A 1 when electricity flows and 0 when it does not. larger computer networks (like the internet) send data using light instead of electrcitiy. The light still goes in wires (fiber optic cables) and the data is basically the same."
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mb0db2 | why can't we just use complex sugars in snacks than simple sugars? | Chemistry | explainlikeimfive | {
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"Well for starters, table sugar - sucrose - is a complex sugar consisting of a glucose molecule and a fructose molecule bound together. In any case, one problem is the body's inability to digest complex sugars. For example, people who do not produce enough of the enzyme *lactase* are unable to digest milk sugar *lactose*. Instead, the lactose *is* able to be digested by lactobacillus bacteria in the intestines, which leads to bloating, cramping, flatulence, and diarrhea. Sucrose and lactose are pretty much the only disaccharides we can digest, and we can't even digest lactose all that well into adulthood. We can't properly digest *any* sugars larger than disaccharides. Much larger sugars like cellulose are an important part of our diet to feed important gut bacteria, regulate moisture in our stool, and bind together stool into solid pieces. Basically: fiber makes you poop better. The flip side is that cellulose doesn't *taste* like sugar. So there are the first two problems: we may not be able to digest it, which may cause gastrointestinal problems; and/or, it may not be sweet, which defeats the purpose of using it to replace the fattening simple sugars. The other problem is where to get the sugars. The sugars that are commonly used are common for a reason: a whole bunch of stuff already naturally makes it. Even in the case of genetically modified crops like corn to make high-fructose corn syrup, scientists didn't make the gene for fructose from whole cloth, it was borrowed from organisms (like fruit) that make a lot of fructose naturally. Unless we can find a crop that's easy to grow in abundance that already produces that sugar, or the genes are easy to insert into an easy crop like corn, it has to be manufactured artificially. Finding a way to chemically synthesize a complex sugar can be prohibitively expensive, especially when you run into the downsides already mentioned above. Fructose is itself very popular among manufacturers because by weight it tastes sweeter than either glucose or sucrose. That means they can use less of it to sweeten their products (which saves money) *and* label it as having (marginally) fewer calories (which means people are more likely to buy it) *and* it's super cheap to get, because corn. There are already artificial alternatives, like sucralose which tastes very sweet but isn't able to be digested so it gives no calories. The problem is that it's way more expensive (in the quantities that manufacturers use) than even natural sucrose, and people complain that it's not natural and avoid it. The other alternative is left-handed glucose. That is, glucose can turn one way (the natural form, dextrose) or it can turn the other way. Pretty much nothing on Earth makes left-handed glucose. We can't process it, so again no calories. BUT also again nothing on Earth makes the stuff naturally so it is also relatively expensive.",
"Sarcastic answers aside, the point of sweets is to be sweet. The word you’re looking for is complex carbohydrate, carbs come in three varieties fibre, starch, and sugar. Fibre is not digestible by humans, starch and sugar are digestible. Only one of the three types of carbs actually tastes sweet and they are sugars.",
"Because they cost more, so the shareholders hate them, so... Enjoy your High Fructose Corn Syrup. When you make corn cheaper than air, the process to turn it into someone sweet costs less than using something that doesn't kill you.",
"Speak for yourself, I shovel pasta down my gullet shamelessly for my tri-daily snack routine."
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mb0jqn | How do the game servers and game clients communicate with one another in online games? | I was wondering earlier if you shoot a bullet in a game, how does the other person take damage? What kind of things are updated between a server and client? What about team games? Lets say I am on blue team, and the other team is the red team, who manages the spawn locations, the server or the client? | Technology | explainlikeimfive | {
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"For the purposes of this post, I'll use your example of a multiplayer shooter game. The simpler part of the question is the spawning positions: typically, that would be the server's job but there is no technical aspect why that wouldn't be done in the client (other than to curb cheating, but that kind of cheat is typically trivial to detect server-side). As for the rest of the question: because of the time it takes for a message to get from client to server (and vice versa), the server and each game client actually have slightly different game states. That is to say, the game you're seeing is, in fact, *slightly different than what it actually is*, because the server is the source of truth for what happens in the game (read: whatever the server says, goes). Every client is a little bit late to the party, so what you see on your screen has actually already happened (i.e., you're playing in the past). Each individual update from the server to client (and from client to server) is sent via packets, which you can think of as boxes containing tidbits of information, going either direction. How often these updates are sent by the server and the client in shooters is what is referred to as \"tick rate\". So, in a 128 tick server - that's *ticks per second* \\- you'll get and send updates 128 times a second. In figuring out how to display an accurate game state, the client actually has to do some guessing (how exactly that's done is fairly complicated) because displaying an exactly correct game state would require zero network latency, which is (physically) impossible. Another aspect of this is to answer the million dollar question: who shot first? In CS:GO, for example, the server does what is called \"latency compensation\". To simplify, the server takes into account the time that it takes for it to receive a message from clients 1 and 2 (the two players shooting at each other), and factors that when calculating the real time either shot was fired. That's also why there is a peeker's advantage: what you're seeing has already happened, *unless you're doing it yourself* (in which case, you're on time and *everyone else is late*). Since the other guy sees you later than you see him, you get a few extra milliseconds to take his head off before he does the same to you. & #x200B; TL;DR: the server is typically the source of truth in a multiplayer game (and *should always be*), but the client holds a game state to be shown to the player. The client receives inputs, processes them, and simultaneously shows them on the screen and sends them to the server, which processes them, updates its own game state, and sends updates to the other clients). & #x200B; edit: if you wanna read more, the folks over at Riot have a *great* writeup of how a lot of this works (jsyk: it gets technical). I highly recommend this one, it's a great read: [ URL_0 ]( URL_0 )"
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mb1597 | Why do different SSRIs produce different results if they all do the same thing? (inhibit the reuptake of serotonin) | Biology | explainlikeimfive | {
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"You can see here that each SSRI works on different neurotransmitters URL_0",
"They don't all \"do the same thing.\" It's not just \"more serotonin.\" They interact at a lot of different receptors, and with different affinities. They have different pharmacokinetics. This means they don't have identical effects."
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mb1vkd | How does a trade in work if I have negative equity? Do I get my value minus what I owe subtracted from the total of the new vehicle? | Other | explainlikeimfive | {
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"Your negative equity is added to the purchase of the vehicle you’re buying. If you’re buying a car for $5000, trading in a car worth $1000 but you owe $2000 on, you’ll need to pony up $6000 total to walk away with the new car.",
"They will roll the negative equity into the new loan. New car is worth $30,000. Old car is worth $10,000. You still owe $12,000 on old car. So your trade in is worth -$2000. So they give you a loan for $32,000 for the new car. Banks tend to not like this, since now they have a loan out for more than the vehicle is worth. If they have to repossess the vehicle, they can't sell it and pay off the loan. Dealers like to inflate the selling price to get around this. It's a $35,000 car, but they'll sell it to you for $30,000. And they tell the bank, $32,000 loan on a $35,000 car, no issues here! Be very careful doing this, you can get yourself into trouble if you keep doing this, where you have a huge loan on a worthless vehicle. It might be worth it one time to get yourself out of an expensive vehicle into something more affordable."
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mb2l3o | Why does chalk for deadlifting make gripping easier and less slippery, but for pool/billiards chalk makes it "smoother" and easier? | So when deadlifting, using chalk makes it so that your grip wont slip. Your fingers wont slide as easily. However when playing pool, chalk seems to have the opposite effect? The pool stick slide much more smoothly with chalk. Why is this? | Other | explainlikeimfive | {
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"In both cases the chalk increases friction. Chalk on the pool cue doesn't make it slip easier, just the opposite. If you don't use chalk it's way easier to have bad contact with the cue ball.",
"That's two different dusty substances called \"chalk\" because of their looks, not chemistry. Lifting chalk is rosen, like baseball pitchers use. Pool chalk is more like talc, to coat your hands to keep the skin dry.",
"Different chalk. Weightlifting chalk removes moisture from your hands to reduce the possibility of slipping. Pool cue chalk adds texture as pool cues tend to become smooth over time."
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mb2tu5 | Why does welding cause that sort of rainbow effect? | Basically what the title says, why does welding leave the metal with a faint rainbow coloration? | Other | explainlikeimfive | {
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"The color is a result of oxygen coming into contact with the metal while it's still very hot. Welding torches pump gas (usually argon or helium or a mix of the two) into the area of the weld to prevent oxygen from mixing in with the molten metal and ruining it. The color depends on the temperature of the metal, with light gold being on the lower end, blue being in the middle and purble being in the high end, and if it is still motlen when oxygen gets in, it turns dark gray.",
"Hi, physicist here. While others are partially correct that it has something to do with the metal being heated and oxidizing, what causes the rainbow-y effect is something called thin-film interference. Just like how a thin film of motor oil on top of water has a rainbow-y color, the thin film of oxide that forms on the surface of the metal during welding can do the same. (this is a bit more than eli5) How does a thin film produce different colors? As you may know, visible colors have a wavelength of about a few hundred nanometers (red being around 700nm, and blue is around 475 nm. When a thin film of oxide is a multiple of, say, 700nm, it enhances the red color. When it's a multiple of 475 nm, it enhances the blue color. Because the welding process is not very uniform, you can get different thicknesses of oxides and therefore get a rainbow-y color",
"It's not really the welding itself as much as just applying sufficient heat to iron. You can get the same sort of effect in a forge. You get the iron hot enough to overcome the activation energy barrier to nearly instantly react with oxygen in the air to form iron(II) oxide. The color it reflects back into your eyes is dependent on the crystal structure of the iron(II) oxide, and the *exact* crystal structure is dependent on the *exact* temperature it formed at. So unless the heat is *exactly* evenly distributed across the surface of the iron (which it never is), you end up with bands of different colors."
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mb3856 | why did the tectonic plates shift causing pangea to split up? | I understand pangea broke apart because of tectonic shift and mantle movement or whatever but what caused such a severe shift that made entire continents travel so far. | Earth Science | explainlikeimfive | {
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"The mantle is always moving, up in some places, down in others -- and sideways in between at the top. That flow drags the crust above it, which is divided into relatively-hard \"tectonic plates\". Some of the plates have large amounts of continental rock on them. About 300 million years ago, a downdraft in the mantle caused a couple of large plates to crash together, creating the Appalachian Mountains and the supercontinent of Pangea. About 200 million years ago, an upwelling in the mantle created a rift zone under Pangea. The land split apart, creating the Atlantic Ocean.",
"It’s a gradual process. Even now the continents are moving away and towards each other. At a rate of up to 100mm per year. That 1 meter every century",
"The tectonic plates are always moving because they're floating on a sea of molten rock. There are currents moving through the molten mantle of the Earth just like there are currents moving through the ocean. Pangea wasn't the original configuration of the continents, they drifted into that configuration and then drifted back out."
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mb3akg | How do humans intuitively tell whether music is major or minor (happy or sad)? How do we decide which is which? | Other | explainlikeimfive | {
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"That's not what major or minor means in music. Do you mean, why do we ascribe sad feelings to music in Minor keys?",
"\\ > major or minor (happy or sad) Those aren't the same thing, so you are asking two separate questions here. 1. **Major vs minor** is a physical concrete property of different note combinations. A perfect 3rd interval IS major and no one can dispute that. Asking how you can intuitively tell boils down to \"that's how your perception works.\" It's kind of like asking how you can intuitively tell one smell or colour from another. They're just different, and perceiving them gives you a different experience from one vs the other. 2. **Happy or sad**: Well, \"Major = happy, minor = sad\" is a cultural thing specific to Western (aka Europe and North American) music. In lots of other cultures, minor doesn't mean sad (eg Jewish folk music is almost all minor). Even in Western music it's not always true. There are minor songs that are happy, and vice versa. They are just more rare, not the norm, so over a lifetime of hearing typical music your brain pairs major with happy. The consonance vs dissonance other answers are mentioning here also plays into it. There is some physical basis for major sounding more pleasing (leading to it naturally being used for \"happy\").",
"It comes down to consonance and dissonance. Major key is more consonant between the notes, and what that means is that the ratios of the frequencies of the notes are more simple fractions. For example, 2/3 is more simple and sounds more intrinsically pleasing than something like 17/63. Beyond major and minor keys, there are modes of keys, with those modes each having their own level of dissonance. That's why certain styles of music gravitate to certain modes.",
"Repetition. As we grow up we hear constant samples of happy and sad music across different genres and this teaches our unconscious to pick out the initial emotion. We listen for rhythms we’re familiar with too and tempo: slow typically sad, happy typically fast paced, etc. Hope that helps",
"I'm not an expert but I think you mean biologically/neurologically instead of intuitively. However, other characteristics of music such as key are not as well-understood. “That's a bit of a mystery, why we assign major chords with positive emotions and minor chords with negative emotions. There's definitely an element of learned association, although there are some people who claim it's more of a biological thing,” said Jolij. “It's still one of the big questions in musicology.” From URL_0"
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mb3c23 | How does the SuperNova Early Warning System (SNEWS) work? | Physics | explainlikeimfive | {
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"When stars start collapsing in on themselves and getting ready to explode, they emit neutrinos of a particular energy level and burst duration. The stars start spewing those neutrinos prior to the nova. They travel at almost the speed of light, and are produced before the explosion, so for nearby stars, the neutrinos will get here before we can see the nova. The SNEWS has many neutrino detectors. When the neutrino detectors start picking up bursts of neutrinos that match the energy and duration we expect from a star getting ready to explode, they alert astronomers to look at where they came from, so maybe we can see the supernova. Depending on the distance from earth, SNEWS might give us a few hours to a few minutes to get the telescopes pointed that way so we can see it and record it. It's like if you needed to know when your sick brother was going to puke so you could get a bucket under his face. You don't know when he's going to puke or where, and you can't just have buckets everywhere, so you'd listen for when he starts making those gurgly belches, and then rush over with the bucket just in time to catch the puke so your parents don't see the stain and the carpet and find out you've both been drinking.",
"When a star goes supernova it squeezes down really tight then the fusion in the core runs away and accelerates the outer layers outwards, but they have mass and take a bit to get up to speed and the photons in the core of the star get caught on the outer layers so you don't see the big flash until the outer layers get thin enough. Neutrinos are super tiny particles that still have mass but don't really interact with anything. Trillions passed through your hand just now with pretty much no effect on anything, there might have been a single collision. When the fusion in the core of the star is running away its producing a huge amount of neutrinos which can pass through the outer layer of the star and move towards us at nearly the speed of light. There are several neutrino detectors scattered around the world, mostly in deep caves, and if a big pulse of neutrinos triggers them we can use the relative timing of the triggers to figure out what direction it came from and point telescopes that way to watch for the visible supernova that should appear shortly. Its basically relying on neutrinos not interacting much to give us a tiny early warning of where to look for a supernova before any light from that supernova has even reached us"
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mb3yq3 | why are black holes so important to physics? | Physics | explainlikeimfive | {
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"First and foremost is up until quite recently black holes were a theoretical possibility based on the current model of relativity. That is, this model said, mathematically, objects such as black holes could exist under certain situations. But it took quite a while before they were indirectly observed and only very recently before they were directly observed. This is quite the boon in terms of support for relativity. Second while their existence boosts relativity, they also pose quite the challenge. Black holes, being quite small, require the use of the other main pillar of modern Physics: Quantum Mechanics. The problem is, quantum mechanics and relativity don't play well with each other and break down when you try to use them both at the same time. This means our understanding of black holes is incomplete, and we need a new theory that can handle this situation. The other scenario that behaves similarly are the conditions of the Early Universe. Solve black holes and you solve the Big Bang.",
"Two groups of scientist wrote most of physics. One was looking at really big things like stars. One was looking at really small things like quarks. Thing is, if you plugged in the numbers for big things into the small thing equations, or the numbers for small things into the big things equations. It doesn't make any sense. A black hole, is a big thing like a star, squeezed into something smaller than a quark. Plug in its number into either set of equation and you get nonsense answers and not even the same nonsense answer. Scientists have been trying to figure out a set of equations that make sense regardless of what numbers you plug in. One way to check if its working is to plug the numbers for a black hole in and see if it makes sense. Then we need to check if black holes actually do that stuff to see if it's real or just some random math.",
"I wouldn't say they're important so much as they're interesting. We have evidence that they exist. Our model of how the physical world works says they should exist. But at the same time they *shouldn't* exist. Matter falling to the center of the black hole *should* speed up at or almost the speed of light, while other rules of physics say that nothing with mass can travel at the speed of light. Information (as in being able to determine particles previous location and momentum by using the laws of physics to infer where they where previously) should always be preserved, but a black hole seems to destroy it. There is much speculation about how to account for the above discrepancies, but since black holes are so hard to study, they're only speculation. Solving them would give us a more accurate model for how reality works, so of course there's a lot of interest in doing so."
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mb5517 | Do electrons keep moving, or does the energy eventually stop? | Physics | explainlikeimfive | {
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"Electrons can change how much energy they have, but they don't do it through friction, they do it by emitting, or absorbing, a photon. Or by interacting with another charged particle. You're used to seeing things slowing down and stopping because of the bigness scale you exist at - two things made out of LOTS of atoms, rubbing up against each other, have way more ways to take a little of that motion energy and turn it into heat than they do of just bouncing like rubber balls off each other, so if they're not being pushed by outside forces, you eventually end up with them stopped relative to each other, plus some heat. But way down at the electron or atomic scale, there AREN'T carpets and rough walls and grass and dogs and vats of custard, etc. - there's just other particles, and the bosons that carry the forces between the particles. And for a particle, like an electron, to lose (or gain) energy, it has to interact with something else, which then gets (or loses) JUST as much energy. And which might sit there vibrating, which we waaaay up here in Bigland would see as \"it got a little hotter\" - but the energy didn't 'drain away', because it can't. Mass-energy is conserved, you always end up with as much as you started with. --Dave, so SOMETHING will keep moving, if not necessarily the electron you started with",
"The law of conservation of energy states that total energy of a closed system will remain constant. As such, the energy will always remain so long as there are no avenues for the energy to escape. As for movement, the best answer seems to be, it depends. The article on this page will expand on that bit: URL_0"
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mb5yu9 | The effects of isolation for years at a time does to the human mind and body | Other | explainlikeimfive | {
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"Human contact is most crucial during childhood. Children who are raised in complete isolation (such as in extreme cases of abuse) tend to be stunted mentally and physically, and may never learn to talk. Reading stories about instances of feral children can give you lots of examples of this. People who were raised among others but choose to isolate themselves in adulthood seem to fare significantly better, though even then it seems to lead to poor mental health. People in the least populated states in the U.S. have higher rates of depression and suicide. People that make a deliberate choice to live completely alone in the wilderness sometimes find happiness and peace doing so, but it may negatively impact their social skills in the long run, and they may come across as odd or inappropriate. It takes enormous mental fortitude to keep yourself mentally and physically fit when you have no one around to talk to or assist you in any way, but some people manage it. Adults who are isolated against their will can suffer psychotic breaks, with their brains providing hallucinations to fill the hole where socialization should be. Social skills degrade the longer the person is isolated. Many people stop taking care of themselves from hopelessness and lose mobility and strength, and their immune systems are vulnerable to disease. Some general physical effects could be weight loss due to discouragement, hunched posture, trouble speaking, and neglecting personal hygiene."
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mb5zxv | How ants communicate | Biology | explainlikeimfive | {
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"Ant's communicate by \"smells\". They lay down, spray, or emit chemicals. When an ant encounters these chemicals it starts acting differently. For example, if an ant finds food, it'll start laying down a \"food this way!\" chemical trail and head back. Ants will follow the trail and if they get food, they'll lay more of the \"food this way!\" chemical. So even more ants follow, until it runs out of food and the ants stop laying trails. Or if an ant gets attacked it might spray a \"DANGER!\" chemical around, and ants that smell it will start gearing up for a fight or to run away. Other's might emit an \"I am a nest builder\" or \" I am a food finder\" signal. An ant might realize \"haven't smelled a food finder in a while, I think I'll become a food finder\". So it goes find food and starts emitting a food finder smell. This results in very complicated behaviors from very simple rules. Computer guys love this sort of things. They've simulated it on computers to solve non-ant stuff."
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mb63d3 | How alcohol does damage to the unborn baby. | I know that when a mother drinks during pregnancy, the alcohol eventually reaches the baby at some point, causing damage to the unborn child. However, I don't get the details on exactly what happens when alcohol reaches the baby. So I just want someone to please explain this to me. | Biology | explainlikeimfive | {
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"The specific mechanism isn't known. However, they have found that the normal placental barrier that keeps the mother and baby's circulatory systems separate doesn't do anything to stop alcohol or its byproducts in the body from entering the baby. Additionally, the baby is incapable of processing the alcohol into less dangerous materials like adults can. So any alcohol that gets into the baby will persist there and poison the baby until the mother's liver can process the alcohol out. As the baby is still developing, the damage from this can be both severe and permanent. URL_0",
"The easiest way to compare this is to think about the size of an adult liver compared to the unborn childs. The liver will process the alcohol from the blood stream eventually. An adult can die from alcohol poisoning but their tolerance for blood alcohol level is higher than that of a child. Imagine a developing fetus getting blood alcohol poisoning before the liver is even developed."
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mb666w | why is joystick drifting a bigger problem for PS5/Switch controllers when compared to previous console generation controllers? | Like many of you, I have original/OEM controllers from console generations past that still work just fine (ignore N64 for now). So what gives, why now? What has changed with current console generation controller sticks that causes them to drift when we still have Wii/Gamecube/PS3/XB360 controllers that have no problem at all? ELI5 please! | Technology | explainlikeimfive | {
"a_id": [
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"I saw a teardown video of the ps5 remote and it turns out the plastic they use to house the joystick is cheap plastic that wears down easily. So they are made to break for us to go buy new ones. I think it was iFixit I saw it on."
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mb718e | How was the first ever cell formed on Earth? | I have a pretty good understanding of how all life on Earth arose from unicellular organisms in the ocean, but what I cannot wrap my head around is how the first cell came to exist from no life. Secondary sub-question: If it happened once before, does that mean it can happen again on Earth? | Biology | explainlikeimfive | {
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"The short answer is we don't know, but it's being actively researched. Self replicating RNA likely developed spontaneously when the conditions were right. Similarly that block of RNA could have obtained a shell of material which resulted in the first cell. It's likely this happened many times in this era but 'errors' in the RNA wouldn't have allowed most these cells to replicate, or caused problems resulting in them dying almost instantly. Basically Nature tried over and over and over again until it got a cell that worked. DNA testing seems to show every complex living cellular organism on Earth is descended from that first cell. But just as easily we could have 2 different first cells resulting in different roots of the tree of life. Maybe several others existed and only ours won the race to survive. We don't know. How Viruses fit into this is a completely different subject. They may be completely unrelated to us, a stepping stone, or a bi-product. We're not sure.",
"Yeah that question was what motivated me to get a biology degree and I still can't easily answer it. Essentially, all life is is a set of self-replicating molecules. Modern cells group these molecules together as cooperative colonies of molecules that all work towards the common goal of self-replication by delegating tasks, but they're still at core just self-replicating molecules that have evolved some really, really complicated mechanisms to increase their rate of successful replication. Self-replication isn't a particularly difficult thing for an organic molecule to do. Self-replicating organic molecules can arise spontaneously, and it's thought that the first of these were self-replicating RNA molecules (which to this day form the backbone of all biology). RNA is pretty special in that it can both self-replicate *and* interact with other molecules. The ribosome - the bit of a cell that translates messenger RNA into proteins - is made up of RNA itself. Meanwhile, the whole \"cell\" thing isn't too tricky either. Cell membranes are built up of molecules called phospholipids. These spontaneously rearrange themselves to form the cell membrane structure when exposed to water in a very similar way to how bubbles work, only here the shell of the bubble is fat, not soapy water, and the contents are water, not air. The bit that's really whacky about the emergence of life is how self-replicating RNA evolves to produce the complicated, indirect self-replicating DNA system. DNA can't replicate without the help of proteins, which means DNA must have evolved after ribosomes and after proteins. The earliest life must have had ribosomes capable of creating proteins from an RNA template and RNA capable of storing the information the ribosome reads, and the evolution of that interaction is truly baffling. Once you get that going it's relatively smooth sailing from there, though - randomly mutate a protein that can unzip doubled-up RNA strands (which is almost the same as DNA), randomly mutate that to build and unzip DNA instead, and you've got a DNA system good to go. Life could theoretically emerge again on earth. There could even be life at the very bottom of the ocean around undiscovered geothermal vents, or in similarly isolated locations, that has actually sprung up from a completely different evolutionary lineage. However, this seems to be extraordinarily unlikely based on the evidence available (eg the fact we've never discovered it) and if it was true we wouldn't necessarily have any way of knowing about it."
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mb778p | How does cruise control in a car work? | Technology | explainlikeimfive | {
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"There's a speed sensor on the axle. It measures your ground speed. It sends a signal to a vacuum actuated link to increase or decrease throttle input so that the speed matches your setting. It basically just pushes or releases the throttle. That's the old way. A lot of cars have adaptive cruise control now that use radar ranging to determine distance between cars and adjust for that as well. Some will also pre-load the brakes and give you a warning to start braking in the case that traffic stops quickly. Those use an electric throttle position motor instead of vacuum. It's surprisingly simple. It's been a long time since I've installed a cruise control so I don't know how many use electric instead of vacuum. Regardless, the principle is the same. Sensor on an axle, match the speed by change in the signal."
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mb79tv | how does being hypnotized work? And how is it effective for some smokers in order to quit but not others? | Back in high school I saw an amazing magician act that made the most egotistical person in our class do things that she wouldn’t dare do in public and I was sold. She is also a terrible actress so I’m so sold 😭 | Other | explainlikeimfive | {
"a_id": [
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"Pulling everything I know into something that logically makes sense: Your mind is a filing cabinet. When you thing, you're actively adding and removing files from the filing cabinet. Hyptoism work by distracting your conscious mind. While your conscious mind is distracted, the filing cabinet is free for things to be added and removed. As such, the hypnotist jumps in and adds suggestions that builds bridges in the filing cabinet that makes sense. When the hypnotist breaks the trance, the bridges set up remain. As for why it doesn't work for everyone, some people really like focusing on their own filing cabinet and aren't able to be as easily distracted to the point where their entire focus is on the hypnotist."
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mbb9f1 | Why do nuts and seeds taste significantly better after roasting them? | Chemistry | explainlikeimfive | {
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"text": [
"Because you end up roasting out some of the water and caramelizing the naturally occurring sugars, giving a deeper, sweeter flavor. Roasted nuts weight less than their unroasted counterparts due to the water loss, and therefore the fat content by weight increases, which helps amplify the flavor as well. If your roasted nuts taste burnt and are only salvageable by salt, you're doing it wrong. 🤦♂️"
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mbbq77 | What exactly is free Gibbs energy? | Chemistry | explainlikeimfive | {
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"text": [
"Okay lets take a look at thermal energy. Everything contains thermal energy according to Temperature times Mass times Specific Heat Capacity (material property). So E=c*T*m That means the oceans at roughly 280 Kelvin and an insane mass contain a lot of energy. But we can't use it, because of thermodynamics. To make thermal energy usefull we need to move it from a warmer to a colder area, wich allows us to extract a fraction of that moving energy. (Because thermal energy always wants to spread evenly, wich is basically what entropy means) What we need is an entropy sink, that our ocean water with a given higher entropy wants to equalize with. Take a pot of boiling water. It also contains energy, a lot less though at 373 Kelvin times maybe 1kg. Still this pot contains more usefull energy because you can easily find colder water and let the hot water do work (for example by evaporating and escaping through a turbine). So your pot has a Gibbs energy while the ocean doesn't. Both of this has to be seen in relation to the enviroment though. Teleporting our ocean to a colder planet would suddenly make it very usefull, it's just that we have not big source of even colder water available here. So the Gibbs energy is the total energy of a system, minus the part that you can't use because of entropy."
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mbcekd | After tendonesis surgery, how does your body continue to move correctly if the tendon isn’t attached in the same place anymore? | How does your arm still lift the same way? Shouldn’t this mess with muscle memory or the signals your brain sends on how to move your arm? | Biology | explainlikeimfive | {
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"Individual muscle movements are pretty simple. You can pretty much only contract and relax them, and since the biceps muscle’s only job is to pull the lower arm in a particular direction, so long as you keep it in the same plane as before, it doesn’t matter too much where the tendon is attached because it’ll still pull the lower arm. Now, does this cause some issues with throwing off some finer movements and misjudging how much force you’re using to do something? It’s certainly possible. But the brain can adjust to that sort of thing pretty quickly"
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mbco0v | how can a taser have high voltage but low amps | it's something you hear a lot that the amps kill you but I don't get how that works bcs ive always learned that your voltage is amps times resistance | Technology | explainlikeimfive | {
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"Taser has very high output resistance = > high voltage only if there is no load. That means that it can't really keep the voltage high, because once you connect something to the output of the taser (like your body) the voltage and therefore current drops. It's like having a motor that spins very fast, but once you try to stop it with your hand it stops easily. Spinning = voltage, torque = current, friction of your hand = resistance.",
"Think of Amps and Volts like a flow of water. Volts are the speed at which the water flows and amps is the amount of water flowing. Dumping a bucket on your head would be high amperage low voltage. This would be like a high cranking 12v car battery. Lots of juice but won’t kill you. Think of a taser like a pressure washer. High intensity, but less flow of water. What’ll kill you is a fire hose, lots of water at lots of speed!",
"That is the case, yes, but there's also the issue of how much power you have in storage. Amps x time = battery capacity (based on how long the battery can run (when providing x amps) before its drained) Tasers use a fancy kind of battery called a capacitor that can discharge itself really really fast without damaging itself. This capacitor is slowly charged by a \"normal\" battery, but rapidly drained when you pull the trigger. So what happens is that yes, there's super high voltage, and during that moment of super high voltage there's also a lot of amps, but that only lasts for a short moment before the capacitor is drained, and the current stops. That short electrocution is enough to stun, but not enough to kill. If you could hook it to to a strong enough power supply (and with strong enough cables that wouldn't overheat and melt) then it would kill you after a few moments.",
"The whole amps kill is itself kind of bullshit. Let's imagine electricity as water. Current is flow and voltage is pressure. A bucket of water just sitting around is low pressure low current. Would be pretty hard to kill you unless you just stick your face in it. A waterjet cutter is high pressure low flow. The water coming out is at extremely high pressure but there isn't a lot of flow. That can absolutely kill you if you just waterjet a hole into your chest. Now imagine a swiftly flowing river, high flow low pressure. That can also kill you. So back to the electrical domain, current is basically how fast the electrons are flowing and voltage is how hard you're pushing those electrons. So the taser is kind of like the waterjet, it's a ton of pressure but the total amount of water you get hit with isn't a lot, not enough to fuck you up too bad.",
"The voltage and current are limited by the resistance of the medium. E.g if you shorted the prongs on a stungun with copper wire, it'd run many more Amps (and therefore Volts) than if you used it on a person. Frankly, I wouldn't trust manufacturer's numbers when it comes to stunguns. [Electroboom did a piece on this on his youtube channel.]( URL_0 )",
"I think of it as \"draw\". How much \"draw\" is going through you. You are quite resistant. 240v on a 50 amp breaker can kill you if you're wet and earthed across your heart. Not likely, but possible. 120v on a 20 amp can also kill you but you'd need a good draw across your heart. A taser is surface. It's pain. It will lock you up for a sec, but it doesn't cross your heart so it won't hurt you. A 120,000v coil won't kill you, but it hurts like the dickens. 150 amps from a welder through your whole body tends to run across the outside so it doesn't hit your heart. Grab both leads with hands dipped in salt water should be good enough to stop your heart if your heart is no good. If your heart is fine, you'll be fine. We all earth-out here and there. Not fun, but no big deal. It's all in the resistance. Step up to 480v@250 amps. Now you have trouble. If you earth out at 240, you'll trip the breaker. You won't trip 480. My best earth was at 240v. Sitting on concrete, soaked in sweat, earthed out to my ass. No burns but it hurt like hell. My dad earthed out to the ground lead once at 240v@140 amp right through his arm to his ass. Didn't pass his heart so he was OK but it locked him up pretty good until I killed the welder. He had forgotten that the whole combine was earthed."
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mbcyke | How come deep water is always cold when actual closer to the center of earth’s hot core? | Earth Science | explainlikeimfive | {
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"the earths core is about 6300 KILOMETERS away from us on the surface. some really deep water is at best 10 kilometers from the surface. it is still 6290 or so km away from the center of the planet. the surface gets heated by the sun, the water deep down however doesnt get much sunlight (as its absorbed by the water in the upper layers)",
"The densest that water gets is at about 4°C. So if water cools at night or by evaporation, it sinks down to the deeps. Although there can be small amounts of geothermal heating if water is far enough down, water warmed that way will be less dense than the colder water so that will rise up to near the surface. So deep water is always going to be close to 4°C. Ignoring other effects like currents, salt concentrations, etc.",
"The sun has a chance to warm the water at the surface. While most of the water in the ocean is very far away from the core so it has very little effect on the water temperature."
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mbd1r4 | What is the carbonation in carbonated water? | I assume there's some sort of chemical thing going on which makes the bubbles remain there, as opposed to when I blow bubbles through a straw in a glass of water. And when carbonated water goes flat, it still has that "flavor" even without the bubbles. Extra credit if you'd care to explain how "naturally" carbonated water like Perrier fits in there. | Chemistry | explainlikeimfive | {
"a_id": [
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"text": [
"Carbon dioxide naturally dissolves in water; under pressure you can dissolve an awful lot of carbon dioxide, but when you release the pressure some of the carbon dioxide will quickly come out of the water."
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12
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mbdj3v | How does adding club soda to batter make fried foods crispier? | What’s the science behind it? | Chemistry | explainlikeimfive | {
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],
"text": [
"Club Soda adds one main thing to the batter, and that is carbonation. Carbonation is basically just loads of small gas bubbles, so adding that to a batter adds all these small bubbles to the batter. When you go to fry the batter, the batter cooks around these bubbles creating small pockets of air. So instead of getting just one solid layer of batter, you have all these tiny air pockets that create more texture when you bite into it."
],
"score": [
12
],
"text_urls": [
[]
]
} | [
"url"
]
| [
"url"
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|
mbdnqz | What does it mean to re-master audio? | Today I was listening to some Beatles songs on spotify and noticed that the titles said < song name > 2009 remastered. I can't hear any noticeable difference between the remastered and original recordings, as opposed to remastered video where I can usually see better quality in the remastered version. So what is the process of remastering audio and how does it affect the recording? | Technology | explainlikeimfive | {
"a_id": [
"grxbfio"
],
"text": [
"As a general rule, a song goes through three stages - recording, mixing and mastering. - Recording is when they lay down the actual music and vocals. Back in the day, this was all done to tape, but not most of it is digital - Mixing is when they take those recordings, select the 'best' parts and mix them together into the final song. They use a suite of tools to adjust the individual recorded tracks (EQ to adjust tone, limiters to control volume, reverb to add presence, etc.) and put it together into one finished item - Mastering is when all of the tracks for an album are adjusted to create a singular 'feel' for the album. Typically one engineer will make _small_ adjustments to each of the songs so they feel similar and have a flow. This is probably the most nebulous step and the term that is most often misapplied. So when you remaster a song, you either: - Go back to the original recordings and remix using modern tools, or - Go back to the original mix and make small adjustments using modern tools. Either way, the underlying recordings are usually not touched."
],
"score": [
9
],
"text_urls": [
[]
]
} | [
"url"
]
| [
"url"
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|
mbeuhy | How do doctors sometimes diagnose an illness without any tests despite several diseases having similar symptoms? | Biology | explainlikeimfive | {
"a_id": [
"grxelc4",
"grxmgak"
],
"text": [
"Occam's Razor tends to get used a lot. If you come in with chills, fever, cough, and body aches in the wintertime, it's probably the flu. They won't assume that it's meningitis, unless during your talk with him you indicate behaviour or risks of getting meningitis. But if you come in with the same symptoms outside of flu season, they might look harder into meningitis being the case, because the flu would be unusual.",
"Besides using the \"simplest explanation is usually right\", it comes down to experience and/or skill and the particulars of the disease or illness. Some doctors have more experience and have seen more patients with particular issues, so they recognize it. Some doctors are just better at diagnosing. They remember their training better or they are better and connecting the dots of how an illness presents. Sometimes the illness or disease has distinct symptoms that don't overlap with other diseases or illnesses. They may still use tests to confirm depending on the seriousness of the issue."
],
"score": [
18,
4
],
"text_urls": [
[],
[]
]
} | [
"url"
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| [
"url"
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|
|
mbfest | How is it physically possible to push when you have an epidural | I understand how an epidural works. I understand how pushing works. But I can't wrap my brain around the concept that even though you're numb and paralyzed from the anesthetic, you're supposed to be able to push a baby out. Don't you use all your abdominal muscles? How can you use them if you can't feel them? I tried searching but couldn't really find anything on this specifically. | Biology | explainlikeimfive | {
"a_id": [
"grxhwor",
"grxi2z4"
],
"text": [
"Wife just had an epidural 2 weeks ago to birth our child. She wasn't paralyzed, it just numbs the pain nerves. Basically feels like pressure and you use the same feeling of pooping to push baby out.",
"your body knows how to use your muscles even if you can’t feel them. there’s no paralysis. and your muscles don’t just stop working when they’re numb. an example of this would be when someone gets their mouth numbed at the dentist. just because it’s numb and you can’t feel it doesn’t mean you can’t use your facial muscles to talk, drink, or smile."
],
"score": [
6,
6
],
"text_urls": [
[],
[]
]
} | [
"url"
]
| [
"url"
]
|
mbfydq | How are scam phone calls still a thing? | Technology | explainlikeimfive | {
"a_id": [
"grxkn0m",
"grxpmyn",
"grxs57v",
"grxl0jp",
"gry8jb9",
"gry5lme"
],
"text": [
"Enough people fall for such scams that it's profitable enough in some countries to have people running such scam calls.",
"I don't even answer my phone unless I recognise the number. If it's important, they'll leave a message. I've gone by this habit for over a decade now. It's surreal when you think about it. I sometimes see a special government advertised number to text scam messages to, but it never seems to make a difference. Some apps help, like Truecaller, etc.",
"Phone companies could easily filter out most spam/robo calls. They just choose not to. They believe the “No Call List”, which a person has to add their number to every single year to stay on and which is blatantly ignored by many through various means, is sufficient and are satisfied that it shifts all responsibility to the telemarketers, not them. The worst part is, now these phone companies are offering basic scam/robocall protection, at an extra price. So basically they want us to pay them for a service they should really be doing already. All for the sake of profit right?",
"These calls would be vastly reduced if the telecoms were not allowed to sell blocks of domestic phone numbers to offshore accounts. Pure greed.",
"The FCC has not functioned as a regulator or applied any significant oversight to telecoms companies as a matter of course for quite some time now. It reached patently absurd levels in the last Presidential administration, however (I know, I know - I'm shocked, too). The FCC administrator for the last 4 years, Ajit Pai, was a former Verizon corporate attorney, and he (even much more so than previous FCC admins, who were all considered to be more or less politely corrupt) went so far as to claim that it's inappropriate for the FCC to regulate telecoms companies. (Among many other things...I mean, [judge the guy for yourself]( URL_0 ).) This is basically akin to the director of the FAA saying it's inappropriate for them to regulate airlines. More or less a total dereliction of duty, because regulations cost telecoms companies money. I wish I were exaggerating. Fortunately the new Acting Chair of the FCC (who's been a commissioner for some time) has actually started to do something about this, just within the past few months. Last week (March 17, 2021) the FCC levied [the largest fine in the commission's history]( URL_1 ) against a robocaller, to the tune of $225 million. This is the sort of action that may actually move the needle, as it is the first time in a long time that these scammers are actually getting punished. I really don't want to make this political, but in this case it's very, very, VERY obvious: if you don't want these robocall scams to bother you, **stop electing Republicans**. It really is a straight line from there to here.",
"ELI5 answer: by making tens of thousands of calls, they can get a few victims to send them a huge amount of money which makes the entire operation profitable. [Mark Rober]( URL_0 ) made a recent video about scammers where he tracked some down and explains how the scamming system works as well. Probably heard of him, but you should definitely check him out if not. His videos are crazy and genuinely trying to teach you something The scammers basically have headquartes where they can send out thousands of scam calls every day. With the amount of calls they do, they get 1-3 people to fall for their scheme. By getting even just one person to send idk 20000$, they make a huge profit from just doing calls. To add to that, the main victims of scams are elderly people who dont know better. Most of the victims Mark Rober helped out with were old gullible women. One even recently widowed and taken full advantage off because of her husband’s passing. I live in the EU and got maybe 2 unknown calls in my entire life (turning 19 soon). Since my phone just showed “unknown number” I didnt even bother taking their call."
],
"score": [
26,
25,
21,
20,
6,
4
],
"text_urls": [
[],
[],
[],
[],
[
"https://www.youtube.com/watch?v=W2b3vuBhLWo",
"https://www.fcc.gov/document/fcc-issues-robocall-cease-and-desist-letters-six-voice-providers"
],
[
"https://youtu.be/VrKW58MS12g"
]
]
} | [
"url"
]
| [
"url"
]
|
|
mbgn8m | When light enters glass it refracts and it's speed drops from ~300,000km/s to ~200,000km/s, when it leaves the glass it goes back to ~300,000km/s immediately! Where does the re-acceleration force/energy come from? | Physics | explainlikeimfive | {
"a_id": [
"grxpkzq"
],
"text": [
"The frequency is changing. When the light slows down, the frequency increases (shorter wavelength) and the energy of a photon is proportional to frequency. Keep in mind that photons don't have mass so they don't carry kinetic energy they way we'd normally calculate it, but they do have momentum and mass-energy. If you crank through the mass-energy equivalence you should get out that the total energy involved hasn't changed."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
]
| [
"url"
]
|
|
mbgv4t | How is the body heated exactly? | So I understand the human body has mechanics to keep heat in (close pores ect.) or release heat (sweat ect.) to maintain a body temp. However, how does the body generate said heat in the first place, and why do you get hotter when you workout/exercise? Because if there was no generating of heat, you would just lose it all regardless of your body trying to keep it in. Am I being stupid or it it like the friction of the blood in you veins? Idk | Biology | explainlikeimfive | {
"a_id": [
"grxqnrr",
"grxrp8k"
],
"text": [
"When your cells process glucose into energy (simplified), they generate some heat as well. Multiply that by how many times it happens in each cell and then by how many cells are in your body to get an idea of how you produce heat. When you're exercising, your cells are going into overdrive, so they're making much more heat than normal.",
"Think of a combustion engine. Tiny little explosions when you mix the fuel with oxygen, the explosion moves the piston, and off you go. The body also has fuel called glucose. Your body uses the oxygen you breathe to mix with the glucose and Bang! you get heat. But instead of making a piston move, you make a molecule called ATP which is used in most functions of the body."
],
"score": [
7,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
]
| [
"url"
]
|
mbhnog | Why do we commonly eat lamb over mutton but not veal over beef? | Other | explainlikeimfive | {
"a_id": [
"grxxaql"
],
"text": [
"Mutton is generally considered to be pretty low quality hence why lamb is preferred over it. Where beef is far more sustainable from grown cattle and of perfectly fine quality. So harvesting young cattle to obtain an edible product isn't necessary"
],
"score": [
4
],
"text_urls": [
[]
]
} | [
"url"
]
| [
"url"
]
|
|
mbhpqa | What part of the brain tells you which side of your body to lay on while you’re sleeping/trying to sleep | Sometimes when I’m laying in bed trying to fall asleep I’ll just have this gut feeling, like if I lay on my left side right now I’m gonna pass out. It’s different, sometimes it’s my back, or right side, or stomach etc. what part of the brain does this and why? | Biology | explainlikeimfive | {
"a_id": [
"gs07rkx"
],
"text": [
"I don’t see any answers under this so my (kind of) educated guess is you’ve just conditioned yourself though coincidence! You fell asleep on one side of your body a few too many times and now you’ve been subconsciously convinced it’s the key to a good nights sleep!"
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
]
| [
"url"
]
|
mbi3g6 | How does immune system distinguish between "good" bacteria and "bad" bacteria in the gut? | Biology | explainlikeimfive | {
"a_id": [
"grxywx8"
],
"text": [
"It doesn't. Inside of the gut is basically outside of your body so there's little immune defense (generally just IgA antibodies). The main mechanism good bacteria have is that they don't hurt our guts, don't produce toxins, they don't destroy the tissue. Intact tissue means no inflammation, which is the main trigger for immune reaction. But if these good bacteria somehow overgrow, or they happen to enter the tissue (trauma, or necrotic bacteria cause it) they become bad for the blood/organs. This is what we call opportunistic bacteria."
],
"score": [
9
],
"text_urls": [
[]
]
} | [
"url"
]
| [
"url"
]
|
|
mbild5 | Why isn’t friction affected by surface area? | Physics | explainlikeimfive | {
"a_id": [
"gry21nh"
],
"text": [
"Because surface area doesn't chance the amount of mass/force exerted on the surface. The same force exerted over a larger area means less force per unit area, but more area. So the \"friction\" generated in each unit area is less, but the total friction over the entire contact surface is the same. The surface area of contact is important for other considerations, such as material integrity. If your brakes were focused to a single point instead of an entire pad/drum, they would pierce through the surface rather than grip it."
],
"score": [
15
],
"text_urls": [
[]
]
} | [
"url"
]
| [
"url"
]
|
|
mbirur | If your skin sheds itself over time, how do freckles keep appearing? | Biology | explainlikeimfive | {
"a_id": [
"gry2p39"
],
"text": [
"Cells in the body replicate based on a certain set of instructions that they are given from the DNA that resides within them. Freckles are a cluster of pigmented cells. This means that as those cells replicate, they still contain the instructions for pigmentation. On the flip side, my freckles went away by my mid teens."
],
"score": [
12
],
"text_urls": [
[]
]
} | [
"url"
]
| [
"url"
]
|
|
mbjgum | What happens if I try to recharge non-rechargable AAA Batteries? | Chemistry | explainlikeimfive | {
"a_id": [
"gry763x",
"gryoyhs",
"grz6gxv"
],
"text": [
"When you try to pump electricity into a non-rechargeable battery it will heat up. Eventually it might get so hot that it will explode. Not recommended.",
"Batteries work with a chemical reaction. With rechargeable this reaction is reversible by pushing energy in the other way. With non rechargeable, for simplifications sake, is not reversible. Pumping energy the wrong way will just heat it up and destroy it.",
"You can actually recharge a regular Alkaline (non-rechargeable) battery, but it comes with its own set of problems which render it commercially unmarketable. For one, they don't have nearly as many recharge cycles as the 'rechargeable' ones, and they can fail in an explosive way. Also, their capacity reduces significantly with each recharge as gas escapes from the battery cell."
],
"score": [
11,
3,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
]
| [
"url"
]
|
|
mbk01e | Why are there no B batteries? | Other | explainlikeimfive | {
"a_id": [
"gryae3k"
],
"text": [
"There are B batteries. They're rare, but they exist: URL_0"
],
"score": [
4
],
"text_urls": [
[
"https://en.wikipedia.org/wiki/List_of_battery_sizes#Cylindrical_batteries"
]
]
} | [
"url"
]
| [
"url"
]
|
|
mbksem | When is pasta considered a pasta salad? Could one then consider all pasta a salad? | Other | explainlikeimfive | {
"a_id": [
"gryfh6u",
"gryi9rl"
],
"text": [
"Pasta salad is typically made with spiral pasta, uncooked vegetables, a salad dressing of sorts, and is served cold. Notice how the uncooked vegetables, salad dressing, and cold serving are also traits found in just about every other type of salad.",
"This debate is the first conversation I had with my wife 10 years ago. We decided pasta salad requires the intention to make a salad, and it has to be cold. Just letting pasta with sauce cool down doesn't count."
],
"score": [
7,
5
],
"text_urls": [
[],
[]
]
} | [
"url"
]
| [
"url"
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|
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