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mq93h8
What is the biological reason for grief from loss of a loved one?
What is happening in our brains? It sounds so obvious, but what's doing what, what's making that feeling of overpowering dread?
Biology
explainlikeimfive
{ "a_id": [ "gueitxv" ], "text": [ "It's not the same with everyone. I remember meeting this couple that would celebrate when someone passed away (don't remember their culture). No one cried, it was more of a party." ], "score": [ 3 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mq941p
Why do we get hungry when we still have energy stored in our bodies?
Like fat reserves. I have an amount of fat on my body but why do I still get hungry every day when my body can just use that fat as energy instead? Doesn't the body use that energy anyways when you don't eat?
Biology
explainlikeimfive
{ "a_id": [ "gufazob", "guejcdz" ], "text": [ "Our bodies have a kind of order they like to use energy in. Obviously your body will use the energy in your food before the energy it has stored as fat, but it goes a little deeper than that. Your body likes to keep around a teaspoon of glucose (sugar) in your blood at any time. Too much sugar can cause serious problems, and so can too little, so your body manages the amount of sugar in the bloodstream constantly. So what happens when you eat a meal that has sugar in it? When you eat a meal, your stomach quickly absorbs the sugar. Your body now has more sugar in its blood than it really wants, so it releases a hormone called insulin. Insulin is like a key that opens your cells’ gas tank and lets sugar come in. The problem is that your cells can only take on so much fuel, so all the extra basically gets stored in your fat cells, both to keep you safe and to burn later. So what stops your body from using that fat? Well, as long as you have any extra sugar in your blood stream your body will *always* use that first. It’s like a safety mechanism. Unfortunately, people snack a lot, and when they snack, they will use the sugars in their snacks for fuel instead of stores fat. If you are constantly eating, you will always be using those fuels. Two things to consider: The first is you need to understand that all carbohydrates are essentially sugar. A tablespoon of sugar, starch, and ‘complex’ carbohydrates are all broken down into glucose. Enzymes in your mouth will start to break starches down immediately, and your stomach will quickly break down more complex carbohydrates. You can think of complex carbohydrates as time-release sugar. Fiber slows down the absorption of sugar somewhat. The second is that when you eat a meal with a lot of carbohydrates, a lot of the calories end up in storage unless you burn them pretty quickly. So you may have eaten a 700 calorie meal, but you maybe only got 400 calories worth of energy because you couldn’t process it enough. So that meal should have been enough to keep you going for hours, but since a lot of it got stored, it doesn’t keep you going for as long, and you get hungry sooner than you might like. If you ignore the hunger for a while, you will eventually start burning fat, but most people opt for a snack because being hungry doesn’t feel good. This is why you see people have so much success losing weight with things like intermittent fasting; they give their bodies enough time to actually burn some of the stored fat instead of just eating more food.", "Because fat reserves are made by the body in preparation for times of starvation. Our bodies mire easily process high energy foods into immediate energy, so very sugary foods are what we crave because they provide us with *immediate* energy. Further, fat stores do not provide necessary nutrients, and we crave certain foods that provide those nutrients that cannot be provided by fat reserves alone." ], "score": [ 19, 12 ], "text_urls": [ [], [] ] }
[ "url" ]
[ "url" ]
mq9btf
How did early natural philosophers explain things not "falling off" from spherical Earth?
Natural philosophers in ancient Greece knew that the Earth was roughly spherical, and were even able to calculate its diameter to great accuracy; but how did they reconcile this with how something might exist on the "bottom side" of the Earth without falling off, almost 2000 years before Newton? Did they also think that one could actually go around the Earth, or did they come up with some other explanation, e.g. that the known world was restricted to the "top side" of the Earth, with the "upside-down" part being just sort of a lower surface of a floating rock? Or something else?
Earth Science
explainlikeimfive
{ "a_id": [ "gufcctz", "gufctso" ], "text": [ "In the 4th century BC Aristotle thought that the 4 elements just naturally wanted to come together. 1st century BC they knew density mattered. 11th century they knew it was some acceleration attraction and started making theories similar to potential energy. 17th century they knew the acceleration was constant. Newton came later in the 17th century and put gravity into math, which was then modified by Einstein.", "Newton was not the first to discover gravity, he was just the first known to give it some good numbers, which was probably in part the result of doing this in the modern era and therefore having the work much better preserved - it could be that someone else did the same maths centuries before, and the documents of that were just lost. The vast majority of history has been lost, after all. We've known about gravity for thousands of years, although with different explanations for how it arises. It seems Aristotle thought that \"gravity\" was the tendency of objects to fall towards the centre of the universe, which at the time was thought to be the centre of Earth." ], "score": [ 12, 4 ], "text_urls": [ [], [] ] }
[ "url" ]
[ "url" ]
mq9c4l
what causes someone to sometimes immediately vomit after a shot of alcohol, whereas taking a big gulp of water, soda, etc, rarely has that effect?
Sometimes you take a shot, or even a swig, and immediately know it's coming back up. Why does alcohol sometimes give us that visceral immediate reaction as opposed to other liquids?
Biology
explainlikeimfive
{ "a_id": [ "guek4jg", "gufb5dh" ], "text": [ "Alcohol is a stomach irritant. So, depending on the state of your stomach, your body might have the reflex to reject it.", "We have this instinct where, if we eat something that made us sick before, our bodies will often try to reject or discourage us from eating that thing again. Makes a lot of sense in the wild, where animals aren’t purposely trying to poison themselves. But we humans are funny that way and enjoy a little poison now and then. It’s called the Garcia Effect. If you’ve ever gotten deathly drunk off a particular type of booze (whiskey for example), you’ll notice you have a stronger gag reflex with that particular type of booze." ], "score": [ 14, 7 ], "text_urls": [ [], [] ] }
[ "url" ]
[ "url" ]
mq9gwh
How does the brain tell that an object has gone too far in the mouth and that a person needs to gag? Even when the object isn't touching parts of the mouth.
Biology
explainlikeimfive
{ "a_id": [ "guekzla" ], "text": [ "It's involuntary action. Even though you don't feel it touching, your body does. It's similar to food being in the stomach and u not feeling it but brain knowing about it" ], "score": [ 4 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqa19y
Why is it easier to remember the melody of the song than its lyrics?
Biology
explainlikeimfive
{ "a_id": [ "guepd5g" ], "text": [ "There are less sounds in a melody (as each word is techncially a combination of vowel and consonant sounds.) Also, melodies are predictive and mathematical, based off commonly accepted and trained progressions our ears have heard a million times. Like when you know the note the line in the song is going to end on even if it's the first time you've heard the song." ], "score": [ 7 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqaah7
Can someone explain to me how scammers can use my number to call people multiple times, but I’m completely unaware of it?
Technology
explainlikeimfive
{ "a_id": [ "gueq855", "gues1br" ], "text": [ "It is easy to spoof caller ID. Spammers just rotate through a series of random phone numbers to prevent their calls from being blocked.", "Most people rely on caller id, which is a very different system from what telephone companies use internally to route numbers. For example toll-free 800 numbers can get automatic number identification (ani) which is harder?! Impossible? To spoof. Caller id on the other hand is super simple to spoof, especially of if the caller is using VoIP. It's an audio tone that's sent between the first and second ring. If you're using a very old land line and your quickly pick up the phone, you can hear the caller id signal it's a very brief radio static like sound. The phone company doesn't verify it to be accurate. So you can claim to be whatever number you want. Kind of like you introducing yourself as George Washington, unless someone checks your ID card, they have to believe it as the truth." ], "score": [ 13, 3 ], "text_urls": [ [], [] ] }
[ "url" ]
[ "url" ]
mqb29k
What makes flying a helicopter so hard compared to a plane? Is there a "computer-assisted" mode on modern helicopters that greatly reduces this difficulty?
A few sample questions, any info would be most appreciated: I've heard a bit about needing to constantly calibrate the two rotors (top and tail) to keep the copter from spinning out of control. Any more specific information on these difficulties would be useful -- e.g., what types of changes most frequently occur that lead to instability? Second, given that quadcopter drones exist, it would seem that these dynamic stability issues could be significantly ironed out by a continuous computer-driven calibration. Does that mean that most modern helicopters are now about as "easy" as a plane to fly, or no? Are such "auto-calibrate" features common on newer helicopters? Do pilots like to use them?
Technology
explainlikeimfive
{ "a_id": [ "guevc7w", "guevz6x", "guexeam" ], "text": [ "Edit; Thanks everyone for not attacking this comment for it's simplicity as only the most basic of rototrcraft are operated as simply as this description any longer but understanding these basics will give you a basic understanding of most rotorcraft. It's not just coordinating the tail and the rotors as you describe that's required to control a rotorcraft. It's coordinating the three controls of the rotors, the *RPM's*, the *cyclic* and the *collective* in addition to controlling *Yaw* (flat horizontal rotation} with the pedals by controlling the tail rotor. The *cyclic* tilts the axis of the rotors left, right, forward and back like tilting an umbrella over your head. The *RPM's* keeps the motor in it's most safe and efficient operating speed range, while the *collective* controls the angle of the rotor blades as a group to increase or decrease lift. The tail rotor blows across the back end and by increasing or decreasing the pressure you apply here with your pedals you can counteract the natural tendancy of the helicopter to *Yaw* away in reaction to the torque produced by the main rotor or to control heading or yaw of the aircraft. The cyclic control is in the form af a larger joystick used to aim the lift forward, back, left or right in order to control orientation of the helicopter. If the overall rotor is tilted in One direction the helicopter will move in the direction that the rotor is tilted as long as the collective provides enough lift. The collective is in the form of a lever you pull up on which increases the angle of the blades of the rotor to increase overall lift. Edit; the collective also has a motorcycle grip style throttle incorporated into it that controls the RPMs of the motor independent from the collective control of the angle of the rotors. If you flattened out the rotors with the collective it wouldn't matter how much throttle you apply because the rotors would just be spinning flat and supplying no lift. In order fly you have to increase the RPM's of the rotor and then increase collective to increase the pitch of the rotors and provide lift and then control and direct that lift using the cyclic to tilt the rotors in the direction you want to go while preventing unwanted rotation (Yaw) using the pedals.", "Flying in a straight line like a plane is easy, but that's not what helicopters are good for. Hovering, descending while hovering, and moving from side to side without turning are the three killer apps of helicopter. The only other way to do these operations is with a crane, and flying alongside a plane in a crane is not a thing you can do. It's flying AND doing all these other things that's hard. Computer assisted modes are fine for the easy thing, but the hard things are too hard for computers to do well, that's why you don't even see the US military (with virtually infinite money) building helicopter drones. (OK, the FireScout is a Helicopter, but it's only used from ships so that it can crash into the ocean.)", "The basic problem is the dynamics (the physics that makes the vehicle \"go\"). With proper design choices, it's relatively easy to make an airplane with stable dynamics...it tends to (mostly) stay going in the direction it's pointed unless you do something to change it. As a result, a nicely trimmed airplane just needs slight nudges from time to time and otherwise just keeps flying. Airplanes that are designed to not do this, like high performance fighters, need computer control to remain stable. Helicopters have incredibly messy dynamics. You basically wad up all your normal airplane dynamics equations and thrown them in the trash and start over. Helicopters have a bunch of strange responses (due to basically being giant unstable flying gyroscopes) and you need to learn a whole bunch of muscle memory controls that aren't like anything else to make them do what you want. Unlike airplanes, where you can basically control pitch separately from yaw/roll (and even yaw/roll aren't that strongly coupled), a helicopter is coupled across all three axes. \"Coupled\" means that when you move in one axis, the vehicle responds in at least one other. Every time you change one direction in a helicopter it wants to change direction in two other axes if you don't actively compensate. Just as one example, to go up and down you increase or decrease pitch on the main rotor blades. This increases/decreases torque on the main rotor, which is what the tail rotor is trying to counter. So if you try to go up and don't adjust the tail rotor at the same time, the helicopter will start to spin (yaw). If you try to go down and don't adjust, it will spin the other way. So basically every time you touch the collective (the lever that controls main rotor pitch) you also have to adjust the pedals (which control tail rotor pitch). If you've never touched an airplane but have driven a car, I can stick you in a flight simulator and talk you through taxi/takeoff/flight/(bumpy) landing in about 20 minutes because the motions are intuitive and mostly separate, you just need to get used to how the airplane responds. The control motions for a helicopter aren't like anything else so there's no intuitive baseline to work from. Many modern helicopters have computer augmentation to ease pilot workload, especially in difficult situations like hovering. They are still not as easy to fly as a plane. Quadcopters and the like can't work at all without computer control. Modern human-sized quadcopters (and higher numbers of rotors) are \\*much\\* easier to fly from the human standpoint because they're 100% computer stabilized all the time. The human isn't really flying them, it's telling the computer where they want to go and the computer is figuring out what to do with the rotors. It's essentially full-time autopilot. Very few helicopters are currently built that way because nobody's figured out an efficient quadcopter package using turbine engines and we haven't worked up battery/electric motor technology to compete with turbines on range/endurance/efficiency. It'll get there eventually but high-power multi-rotors are inherently messy because big electric motors are still heavy (although much better), batteries are heavy, generators are heavy, and transmissions are heavy. So you either go with turbine engines are a stupid heavy transmission/shaft system to run the rotors, or go with four+ engines (really expensive), or some kind of turbogenerator with power cables and electric motors (also really heavy)." ], "score": [ 6, 4, 4 ], "text_urls": [ [], [], [] ] }
[ "url" ]
[ "url" ]
mqbdun
why does it burn to put cold hands under hot water?
Biology
explainlikeimfive
{ "a_id": [ "guf0fer" ], "text": [ "We don't feel temperature, we feel the transfer of heat. When the heat is being transferred out of your hands to, say, water, it feels \"cool\". When heat is being transferred out of water into your hands, it feels \"warm\". The bigger the temperature difference between two things is, the faster the heat will transfer, and thus the \"hotter\" or \"colder\" something will feel. & #160; There's an interesting experiment called the \"three bowl experiment\" : Get three bowls. Put ice-water in one bowl, room-temperature water in the second bowl, and fairly hot tapwater in the third bowl. Immerse your left hand in the ice water and your right hand in the hot water for 30 seconds. Then put both hands in the room-temperature water at the same time. The room-temperature water will feel \"warm\" to your left hand and \"cool\" to your right hand." ], "score": [ 9 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqbeht
Can your bladder get used to having more liquid in it so you don’t have to pee as much?
I’ve started drinking a lot more water on a daily basis and it’s causing me to pee like 10 times a day. Will my bladder ever get more accustomed to that much water or will I be peeing this much forever?
Biology
explainlikeimfive
{ "a_id": [ "guey3rz", "guf1b8v" ], "text": [ "Yes you can train your bladder and enhance your bladder control. People who work jobs in nursing and trial law do it all the time. However, it can be unhealthy if you put too much strain on it, and if you try to train your bladder while drinking a large (more than average) amount of water, then you are likely to do just that.", "Your bladder generally starts sending \"Need To Pee\" signals when its about half full. It is possible to get used to that, and to wait a while longer until its almost 100% full. Your bladder won't actually get larger, but most people generally don't bother trying to wait for very long after the first feeling of needing to go, so if they practice they can learn to wait longer between bathroom trips. If anything hurts though, go pee immediately. Pain is never a good sign, you don't want to actually injure yourself." ], "score": [ 15, 9 ], "text_urls": [ [], [] ] }
[ "url" ]
[ "url" ]
mqc2ya
How do we raise and lower our voice?! What is the actual volume handle?
Biology
explainlikeimfive
{ "a_id": [ "guf3fso", "guf4b3l" ], "text": [ "You change the volume of your voice by blowing more or less air past your vocal cords. Kind of like blowing harder in a trumpet creates more sound. The air comes from your lungs offcourse. Edit: The amount of air that is being pushed out of your lungs is controlled by the diaphragm.", "Sound is like waves crashing on the shore of a beach. If the waves are coming in frequently, they're higher pitch. If the waves are well spread out, it sounds lower in pitch. If the waves are too small to knock over a toddler, they're quiet. If the wave are big enough to surf on, they're louder. Our vocal cords vibrate back and forth to produce sound waves. To make our voice quiet, our vocal cords only move back and forth a little. To sound loud, they move further back and further forth to produce sound waves of greater intensity." ], "score": [ 10, 3 ], "text_urls": [ [], [] ] }
[ "url" ]
[ "url" ]
mqch29
Why is it disproportionately men who seem to hate on Greta Thunberg and what is it that makes so many people hate her?
Earth Science
explainlikeimfive
{ "a_id": [ "guf57q4" ], "text": [ "Two words - “toxic masculinity”. They can’t handle the fact that “some teenage girl” is telling them that they shouldn’t drive their big, jacked up, coal rolling diesel trucks. And there’s probably a non-trivial number of bots/post farms that are funded by fossil fuel companies whose sole purpose is to shit on her because she’s fucking up their cash flow." ], "score": [ 7 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqczhi
How is the concept of Eternal Growth plausible? How can that happen without sustainability? If there is always growth, will there always be value?
Economics
explainlikeimfive
{ "a_id": [ "gug36i4" ], "text": [ "In the past, when the economy was primarily measured by harvesting easily-harvestable natural resources and developing wild land, it seemed common sense that eventually that abundance would run out - all the resources harvested, all the land developed. At least a few times per century through the industrial age, there were dire warnings that things would run out and everything would collapse. From [Malthusianism]( URL_4 ) in 1798 to [The Population Bomb]( URL_0 ) and its contemporaries in the late 1960s, to concerns about peak oil in the 1970s. However, all of the predicted doomsdays came and went without much doom. We have about 8 billion people now vs 1 billion in 1800, but the [Green Revolution]( URL_2 ) changed agriculture enough that we have surpluses of food instead of massive global famines. Peak oil will eventually come, but improvements in energy storage, efficiency, renewable energy, and biofuels, are rapidly coming too, so it's not likely to be catastrophic. Basically, whenever we encounter natural limits, we find ways around them or ways to make them irrelevant. Meanwhile, the greater economy itself has drastically changed. In the U.S., ( URL_3 ) all of the agriculture, forestry, fishing, and hunting makes up only 1.4% of the workforce (yet produces abundant surpluses). Industry makes up less than 13% (of which only 0.4% is mining). Services are now predominant, at over 80% and growing. As long as people can do things for each other, the economy could keep growing. Or could it? The population growth rate [began declining in 1968]( URL_1 ) and eventually that could lead to a decline in population, and therefore a decline in both customers and providers of services. Increasing automation could offset that and allow the economy to keep growing, however. Or population could reach an approximate equilibrium state where increased productivity and efficiency still allows for economic growth. When \"what can people think of to create or do for each other?\" is the basis of most of the economy, the imagination becomes the limit." ], "score": [ 4 ], "text_urls": [ [ "https://en.wikipedia.org/wiki/The_Population_Bomb", "https://en.wikipedia.org/wiki/Population_decline", "https://en.wikipedia.org/wiki/Green_Revolution", "https://www.bls.gov/emp/tables/employment-by-major-industry-sector.htm", "https://en.wikipedia.org/wiki/Malthusianism" ] ] }
[ "url" ]
[ "url" ]
mqd1ja
How exactly do certain smells have the ability to trigger old memories?
Biology
explainlikeimfive
{ "a_id": [ "gufc9g0", "gufj5x7", "gug1gjy", "gug7jlh" ], "text": [ "All senses can trigger old memories, but the part of the brain that process smells is closer to the memory-center of the brain than the other senses, so smells trigger the strongest memories", "This happens because the brain tends to store information that co-occurs. Whenever you see a certain object or smell a certain scent, the brain also processes related objects/memories/events that were somehow significantly related", "Don't know, hopefully a neurologist will come along. All I wanted to say is read Perfume by Patrick Suskind. It makes you think and see smells in a different light.", "Not exactly a \"How\", but very basic animals and even some plants communicate by releasing hormones. That ability to sense that information evolved early, long before sight and hearing. So that's a theory why scent is integrated much more deeply in our brains." ], "score": [ 12, 5, 4, 3 ], "text_urls": [ [], [], [], [] ] }
[ "url" ]
[ "url" ]
mqd54q
How does the subconscious works and is it self-aware ?
Like in the title. I know what the subsconscious does but how does it operates ? And is it self-aware like us, our consciousness ?
Biology
explainlikeimfive
{ "a_id": [ "gufaroj", "gufs3ye", "guh3vmd" ], "text": [ "\"the subconscious\" isn't one thing. Rather, it's a colloquial, un-scientific name given to all the processes that happen in the brain that we're not directly aware of and can't directly control. It exists only in contrast to the other colloquial, un-scientific word \"consciousness\", which describes the things we *are* aware of and *can* control. Neither of these terms is a biological term, they're just terms used in psychology to describe phenomena we experience but can't explain. Psychology needs to be able to define these experiences, but it doesn't need to or try to explain them, and neurobiologists are still busy trying to work out how consciousness arises. Personally, I suspect the most likely outcome is that we find out consciousness doesn't exist at all, but is just a weird side-effect.", "Not scientifically confirmed or anything, but I like to reference the [weird side effects]( URL_0 ) of split brain procedures. Interesting \"latent mute second intelligence\" sort of thing arises, with sometimes different preferences and desires.", "Your only conscious self is the one you have in your head right now, reading this. There is no “other” consciousness. Your brain can be colloquially divided into three “parts”: Unconscious Subconscious Conscious Your conscious self is everything you are aware of and everything you do deliberately. Your thinkie-talkie parts. Your unconscious is the part of your brain that runs everything you *never* think of. The bits that keep going even if you were knocked out. The part of your brain that keeps your heart beating, or coordinates your growth from infant to adult. That part. Your *subconscious* can be thought of as the link between the two. This is the part where instinct meets reason, and you get intuition, for example." ], "score": [ 10, 4, 3 ], "text_urls": [ [], [ "https://youtu.be/wfYbgdo8e-8" ], [] ] }
[ "url" ]
[ "url" ]
mqdafa
Why do muscles get tired?
So this may be a dumb question, but I figure as long as we have energy to provide to our muscles, they should keep functioning at normal efficiency. So as long as I keep eating, why can’t I do push-ups all day?
Biology
explainlikeimfive
{ "a_id": [ "gufaaj7" ], "text": [ "Cells store energy, kind of like batteries, and our systems supply them with energy to recharge over time. We don't work like cars, where we can supply more power instantly to a motor, on demand. Instead, it's more like your cell phone, where if you run too much at one time, your battery drains even when it's plugged into a charger. So once your cells get low on juice, that's it - without some exceptional boost (adrenaline for instance) or rapidly consumable energy (carbs - think \"higher voltage\"), the expense of energy is just too much for the supply to keep up with." ], "score": [ 5 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqdput
how does grass(and plants in general) come back year after year after dying? And also, where does grass seed come from?
Earth Science
explainlikeimfive
{ "a_id": [ "gufdw7h", "gufe63r", "gufe3i5", "gufdcmm" ], "text": [ "I live in “the grass seed capitol of the world!” (Oregon) and there are hundreds of thousands of acres devoted to growing grass. It’s harvested for seed and hay. But the grass doesn’t “die” it just goes dormant.", "Grass is a flowering plant. The blades of grass that you see are the leaves of the plant. Most people do not allow their grass to grow tall enough to actually produce flowers. But if you were trying to produce grass seeds, you'd just leave your grass alone, allow it to produce flowers, and then harvest the seeds.", "Y'know wheat? Wheat is just a kind of grass. If we let grass grow instead of constantly cutting it down, it grows fully and makes seeds, just like wheat does. In fact, many of our vital crops are grasses, including rice, barley, rye and bamboo.", "Many grasses and other plants are annual, meaning they live for a year, and each year is a new generation of plant. They have the advantage of not needing to keep a whole plant alive through the winter: they drop seeds in the summer or fall, and those seeds stay that way until spring when they germinate and grow. Grass produces seeds just like any other plant. Perennial plants, which live for more than one year, do a number of things to survive the winter, usually abandoning parts of themselves (like leaves on a tree) and hunkering down conserving as much energy as possible. Kind of like an animal that hibernates" ], "score": [ 29, 20, 17, 3 ], "text_urls": [ [], [], [], [] ] }
[ "url" ]
[ "url" ]
mqf9bn
what is a preferred stock
Economics
explainlikeimfive
{ "a_id": [ "gufnam2", "gufnd2b", "gufp208" ], "text": [ "\"Preferred\" stock is a category of stock that's above \"common\" stock in order of, well, preference. Dividends, as and when paid out, must be paid out to all preferred shareholders before they're paid to common shareholders. They may also have higher dividend yields than common stock, and in the event that a company goes under, preferred shareholders have a claim that common shareholders don't.", "When a company dies, preferred stock gets its money before the common stock. Sometimes there’s no money left for the common stock. Often they have rules that they get dividends before common as well.", "Preferred stock has different \"rules\" than common stock. If a company goes bankrupt and liquidates their assets, there's a particular order that investors are paid out. Preferred stockholders will get paid after bondholders, but before common stockholders. Dividends for preferred stock are sometimes guaranteed. If a company has to suspend dividends because of a lack of profits, they may have to make up any missed dividends to preferred stockholders. Even if it's not guaranteed, any profits are supposed to go to preferred holders before common. The dividend amount is also usually fixed when the stock is issued. Preferred shares are often \"callable\", which means the company can choose to buy them back at a certain price. However, unlike common shares, preferred shares usually have no voting rights for things like the board of directors. Callability plus the consistent dividends mean preferred shares usually have much more stable prices than common stock. For investors, the main advantages over bonds are higher yields and tax advantages in how the dividends are treated (at least in the US). The advantage for companies is that they don't give up any control of the company. And because it doesn't have a fixed date that it matures, it gives the company more flexibility." ], "score": [ 10, 3, 3 ], "text_urls": [ [], [], [] ] }
[ "url" ]
[ "url" ]
mqfuss
Shake, fold, dry... How does it work?
Other
explainlikeimfive
{ "a_id": [ "gufsnn1" ], "text": [ "Two things happening here...one is the shaking. That sheds a lot of water first, so the towel doesn't have to work as hard. Then there's the \"interstitial water\" thing...he means water you trap between the layers of the towel. A towel can trap water two ways..inside the towel itself (between the fibers) or between two layers of towel (between surfaces). By folding the towel you can still absorb all the water you ordinarily would into the fibers, because it's the same volume of towel, PLUS you can trap some more water between the two layers. So one folded towel can hold more water than one unfolded towel. This is basically a fancy way of saying a folded paper towel is thicker than twice the thickness of a single paper tower, because paper towels are bumpy. The space between bumps give you extra places to store water. The combination of shaking to get rid of excess water gets you down to enough water leftover that one towel can't quite hold it in its fibers, but it can hold it if your throw in the \"interstitial\" (between the layers) water." ], "score": [ 9 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqg7pj
How/why does sound travel so far across water?
Physics
explainlikeimfive
{ "a_id": [ "gufuj11", "gufuo8g" ], "text": [ "There's nothing there to absorb the sound on e.g. a lake. It can travel over the water surface without hitting any obstacles. It can bounces off the water surface. It's a light jog for sound.", "The air right above the water is cooler. That makes sound travel slower so it doesn't dissipate into the air as much." ], "score": [ 8, 3 ], "text_urls": [ [], [] ] }
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mqgztr
how birds can glide or fly without getting tired when covering such long distances?
Biology
explainlikeimfive
{ "a_id": [ "gug3jmh", "gufywjo" ], "text": [ "Birds are extremely good at detecting helpful air currents and letting them do the work. They often travel in V shaped formations where they can use the up-current of the bird ahead of them to help them fly. It’s like “drafting” behind a truck, in the same way the truck's movement through the air helps pull a car, larger birds can do the same thing. It can save 40% or more of their effort. (See Joke) Birds are lighter than you’d expect and they have much more efficient breathing. It’s a different breathing cycle than ours. They get a lot more oxygen per breath than we do. Joke: Q: When birds fly, they often fly in a V formation. Sometimes one side of the V is longer than thee other. Do you know why? A: There are more birds on that side.", "Birds have a one way flow of air over their lungs. This allows them to keep lots of oxygen in their blood and fly for long periods of time without rest. They also have hollow bones which are lighter." ], "score": [ 5, 4 ], "text_urls": [ [], [] ] }
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mqig0l
- How does higher horsepower benefit large propeller driven airplanes?
I know that propellers on aircraft start to lose efficiency the closer the blade tip gets to the sound barrier. And I know that blade length, pitch/angle of attack of the blade, and blade velocity all contribute to the thrust that the propeller provides. However, it seems to me that a given blade shape, pitch, and blade length would not have so many variables that horsepower would need to be astronomically high in order to spin the propeller at the optimal velocity. So what am I missing? Why, for example, did the F4U Corsair, benefit from the double wasp, which produces 2800HP? That seems like a much larger amount of power than would be needed to provide optimal rotational velocity at any blade pitch. How does the extra power translate into additional airspeed?
Physics
explainlikeimfive
{ "a_id": [ "gug9w1t" ], "text": [ "There's two things going on. One is that the geometry (prop diameter) pins down your RPM but not your torque. Up to the limits of stalling the propeller blades, if you have more power you can put more pitch on the blades, or add more blades, or put bigger blades, or all three, and generate more thrust from the same diameter propeller. Most high performance propellers are constant-speed, they adjust power by adjusting pitch. The more power available, the more pitch you can put on before RPM starts to drop off, the more thrust you can get, the faster you can go. It's not co-incidence that really high power turboprops either have ludicrously large diameters (Russian Bear bomber), incredibly wide blades (Lockheed P-3), or both (Airbus A400M). The other thing is that piston propeller planes generally have fairly terrible climb characteristics (because climb is a function of engine power and even very large piston engines pale in comparison to the power of gas turbines). More power means better rate of climb at constant speed so, even if the airplane already tapped out on absolute airspeed, having more power can give you better climb rate. In a dogfight, which is all about energy management, a larger engine also allows you to recover energy faster. Edit: typo" ], "score": [ 5 ], "text_urls": [ [] ] }
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mqihv7
What was Japan's endgame in WWII? What was their vision of victory?
Other
explainlikeimfive
{ "a_id": [ "gug95px", "gugcj76", "gugahzb", "gug9ab8", "gugaij9" ], "text": [ "Their original intent was that the US wouldn't enter the war...they thought that, by wiping out Pearl Harbor, the US wouldn't be willing to fight and would abandon the Pacific. Japan would be free to expand the \"Greater East Asia Co-prosperity Sphere\", aka the Japanese empire to encompass China, SE Asia, etc. That proved to be a somewhat strategic miscalculation...when the US entered the war, there was no realistic possibility of Japan capturing the US mainland (Japan didn't have the kind of naval transport or land forces necessary for that while also holding Asia). The objective pivoted to keeping the US from attacking the Japanese home islands, their primary industrial base. If Japan could prevent the US from threatening their military manufacturing, and could get raw materials from the large swaths of Asia that they already controlled, they could achieve a stalemate. The US wouldn't be able to push forward to Japan, the Japanese wouldn't be able to push west to the US. That's part of why they took all the South Pacific islands, those were forward bases to provide defense in depth to Japan and protect their territories in SE Asia. This is why the US put so much effort into fighting tooth-and-nail for nearly uninhabited rocks in the S. Pacific and bolstering their carrier force...once they could directly strike Japan, the stalemate was broken.", "Japan never intended to occupy the US mainland. It probably didn't even want to occupy Hawaii. The idea for winning was called [Kantai Kessen]( URL_0 ) \"Naval Fleet Decisive Battle\". It's helpful to see what happened when it actually sorta worked. Back in 1904, Russia and Japan had a war. In that war, the Japanese basically sank most of the ships the Russians had in the area at the Seige of Port Arthur. The Russians had to send a whole big fleet of ships all the way from Russia. All the while the Russians were getting hurt by their own incompetence. The Japanese fleet fought with it in a big gigantic battle called the Battle of Tsushima and sank most of the Russian ships. The Russians had nothing left to help their ground guys. So they surrendered and let the Japanese have the stuff in the area. Then a couple of decades later the Russian monarchy collapsed (but they didn't care). So seeing that, you can see that Japanese wanted a replay of that. The Japanese wanted to sink most of the ships the Americans had in the area at the Battle of Peal Harbor.(They got a lot, but not enough). The Americans would then have to send a whole big fleet of ships all the way from America. All the while they'd be harassed by the Japanese Navy. Finally the Japanese fleet would fight a big gigantic naval battle where ships like the Yamato would blow up all the American battleships. Then the Americans would have nothing left to help their ground guys. So they would surrender and let the Japanese have the stuff in the area. Then maybe a couple of decades later the American Government would collapse (but they wouldn't care). Longer term though the idea was called \"The Great East-Asia Co-Prosperity Sphere\" Basically, instead of the colonies in South East Asia giving all their stuff to European Powers, the colonies in South East Asia would give their stuff to the Japanese. The rationale being \"it worked for Britain\" In a few decades, Japan would have all the stuff and would be at the level of a big European power.", "Their goal was to take over East Asia/ China and the resource rich areas of south east asia (rich with things like rubber and oil, and of course, people). A Japanese headed sorta pan-asian area. Japan did not believe they could win a long war with the US. Their goal in striking Pearl Harbor was that the US was getting stronger and stronger as time went on, so they would take the opportunity now while the US was weak and do a knockout blow to the pacific fleet, which may give them the edge for a time, hopefully time enough that the US would be unwilling to continue fighting in the pacific against then-superior Japanese navy. Simultaneously, they attacked into SE Asia, hoping to secure valuable resources, which despite getting not much attention, was just as important, if not more than the Pearl Harbor attack in the Japanese plan. They absolutely did not intend to invade the US mainland, nor did they have the capability to do so. Their Army was busy in China and elsewhere in Asia, and that was the priority. Their goal was to put the US in a position that they would look for a peaceful resolution in the pacific, have the US resume trade with them (getting them strategic resources they need), and they could continue their fight in taking East Asia.", "They wanted to conquer Eastern Asia and establish an Empire there. At the time, they were highly dependent on foreign imports so they wanted to control the resource-rich nations around them.", "They wanted to conquer China and southeast Asia, so that resources in those areas could be exploited to support the Japanese economy/state. They kicked the plan off by invading China in 1937. The US was a hindrance to that because they stopped/embargoed their oil exports to Japan, which Japan needed to keep the war going against China. The US was also gearing up for war, against either Germany or Japan (it was no secret at this point that the US and the UK had a close relationship). In their ideal vision, Japan would've crippled the US Navy at Pearl Harbor and seized basically all major Allied ports/cities in southeast Asia in a series of quick campaigns. The Allies would then be hesitant to pursue a war in a completely new front (the Pacific) where they had no forces to speak of (since Japan had destroyed/captured everything). Given the immense local superiority of the Japanese over the Allies, the Allies would then agree to a peace deal that heavily favored Japan; Japan would keep their conquests and have a free hand to conquer China. Was this basically a fantasy? Arguably, yes. The only way it would've worked is if Germany successfully defeats the UK. At that point, the US might not have had the stomach to launch a full-scale, trans-Atlantic invasion of Europe (D-Day, from the UK to France, was already a monumental operation; trying to do that across an ocean instead of a channel would be even more daunting) and may have negotiated a peace deal." ], "score": [ 541, 42, 17, 5, 3 ], "text_urls": [ [], [ "https://en.wikipedia.org/wiki/Kantai_Kessen" ], [], [], [] ] }
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mqip94
Why aren't blimps all that popular anymore?
Other
explainlikeimfive
{ "a_id": [ "gugaadj", "gugfj5o", "gugj2tp", "gugre6l" ], "text": [ "You need a massive massive building to park/service a blimp. They go much much slower than a plane. For all those problems, it still couldn't carry much more than a plane.(especially if you opted for non-flammable helium, rather than flammable hydrogen) Now there are some niche purposes, like the ability to stay in the air for a very long time, but for taking stuff from point a to point b, planes were usually just better.", "One specific problem is that that they can't change their payload much. For example, suppose you built a dirigible to carry 60t. With 60t aboard, it would be nicely balanced. With 65t aboard, it wouldn't go up and with 55t aboard it wouldn't come down. There are ways around it but you can't just load and unload like any other transport. They are also more expensive than land transport, slower than air transport, bulky and vulnerable to weather in several ways.", "Their slight buoyancy means that they don’t need much energy to stay airborne. But. They can’t lift all that much weight, so they don’t have many good use cases. And they are big. Really big. So you need a big hangar on the ground. And they don’t go fast because they have a lot of air resistance. And they are dangerous in high winds/gusts. So even though most of their use cases are similar to helicopters and they’re more efficient, they aren’t used because they’re far less convenient than a helicopter that can land in decently high winds and doesn’t take up a whole hangar when not in use.", "They are simply a relic of the past. Before the Wright Brothers' airplane in 1903, people had actually already flown before in balloons and airships. These \"lighter than air\" craft are simple in construction and principle. Get a gas thats lighter than air, or heat up air, and catch it in a bag with a payload suspended to lift. If you want to lift more and more payload you get more and more gas and eventually you wind up with massive airships like the Zeppelin. People of the age had a vision for these airships as a sort of flying ocean liner that would gracefully float across continents and transport passengers in luxury. This was in the 1920s and early 1930s when commercial airplane airlines were in their infancy so nobody yet knew which would succeed over the other. But by the mid 1930s they had their answer and the future pointed toward airplanes. The very publicized Hindenburg disaster did to the public perception of airships as the Chernobyl disaster did to nuclear power. Meanwhile airplane technology was improving at an incredible pace. The enormous flying boats were making transcontinental travel faster and more economically than airships could have dreamed. And for the passengers it became more about the destination than the journey. Taking days or weeks to travel what airplanes could in a fraction of the time meant that most everyone was choosing the airplanes. So if the airship was now commercially unreasonable and extremely limited in a military capacity, then that was the final nail in the coffin. Since then there have been a handful of attempts at creating more airships but they are either for novelty purposes like the Goodyear blimp or something of a prototype like the Airlander 10. It's really easy to underestimate just how much of an undertaking the giant airships of old were and this excellent video does a better job than I could. URL_0" ], "score": [ 83, 15, 12, 8 ], "text_urls": [ [], [], [], [ "https://youtu.be/ixxXhZVFXxQ" ] ] }
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mqiy1e
How do our sinuses not run out of mucous to produce when they make a lot?
I feel like when I get sick (like right now) I can blow an endless amount of snot. How do sinuses not run out, do we have that much waste stockpiled in us?
Biology
explainlikeimfive
{ "a_id": [ "gugcltd", "guhj2os" ], "text": [ "Since mucous is made from mostly water and protein. The only thing that could make it not be produced as much would be to be dehydrated or hungry for long periods of time", "You don’t stockpile it. You make it fresh everyday. You are basically one long tube. From your mouth down to your anus, you have specialised cells whose only purpose is to belch out mucus 24/7. You also have other, more specialised muck-producing cells that are in special locations for specific purposes - like your stomach-acid-producers, or your skin-oil-secreters. The reason you have the basic mucus-producing model of cell in your top-to-tail tube is to provide a constant source of mucus. This stuff has a bunch of purposes. In your nose, mucus is your very first defence against bacteria, viruses, and random debris you breathe in. Your nose has a huge cavity behind it full of mucus and hairs and bumpy fleshy bits. This area “filters” the air by shaking all those particles into the mucus. This is where your smell receptors are, hidden in that mucus. If you catch any viruses or bacteria in the mucus of your nose or throat, your body will expel them. The mucus lining your nose and throat is constantly being pushed up and out until you swallow it - where everything is destroyed in your stomach. Your nose runs more when you’re sick because this “wash out the bugs” thing goes into hyperdrive. You’re trying to clear the infection by literally washing them out. With mucus." ], "score": [ 5, 5 ], "text_urls": [ [], [] ] }
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mqj17s
Why is it when things have a smooth finish they feel colder to the touch?
Physics
explainlikeimfive
{ "a_id": [ "gugbm8b", "guhad1a" ], "text": [ "A smooth finish traps less air than a corse one and air is a good insulator. This hinder heat transfer from you to the object which makes the corse surface feel less cold than a smooth one.", "You cannot directly feel the temperature of something, you actually feel how much heat moves into your skin or out of it. A smooth surface lets you have more contact for the heat to move out of your body. It feels more cold instead of more warm because unless you live in a desert, 99% of the objects you touch every day have a lower temperature than your body." ], "score": [ 7, 4 ], "text_urls": [ [], [] ] }
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mqj7dz
How does polish work?
Wikipedia says it smooths the microscopic mountains and valleys of a material, but how does a polish do that and does it press the mountain into the valley to create a plateau or does it cut the mountains until everything is in the same "hight" as the previous valleys?
Chemistry
explainlikeimfive
{ "a_id": [ "guge7ek", "gugjeed" ], "text": [ "Most polish is a super-fine abrasive. They create invisibly tiny scratches that “cut the mountains.”", "You're essentially sanding things down. You're grinding down the small lumps on the pain surface. Then you use a wax or filler to fill whatever tiny crevasses you missed." ], "score": [ 7, 3 ], "text_urls": [ [], [] ] }
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mqjkiv
How does swimming help us stay afloat but frantically waving arms in panic cause people to drown?
Biology
explainlikeimfive
{ "a_id": [ "gugf6ik", "gugnz45", "gugfout" ], "text": [ "The laws of physics state that for every action there is an equal an opposite reaction. You use that to push yourself up by pushing down against the water. If you flail your arms you arent putting more force down than up so it doesnt help. Think about the action you use with your hands when you tread water, your hands are more sideways when raising out of the water to cut through it easily and palm down when pushing down to maximize surface area and force", "Drowning tends to be pretty quick and quiet. If someone has energy to panic, they're probably not drowning (yet). Panic has two effects that hasten drowning: First the victim tires quickly from trying to lift their body out of the water. Second, in cold water, it greatly speeds heat transfer by stirring the water in contact with the victim. Most people are approximately neutrally buoyant but their legs are not so if they try to just float, eventually they will end up straight up and down with just the top of their head above the surface and their face under water. Any kind of swimming helps either keep your face out of the water or allows you to lift it long enough to breathe.", "Think of it like a bird on land. A bird moves it wing in a certain way and is able to create lift to rise in the air. Birds can also flaps their wings in a way on the ground without creating lift. Now imagine water as really dense air. When you move your arms and hands in certain ways such as a butterfly stroke. Your hands and arms are pushing against the water much as a birds wing does air. So you're creating a sort of lift. If you sit there and doggy paddle you create lift as well. Just not as efficiently. Now you're panicking and just splash around like a cat in a bathtub. what ever lift your hands and arms create is of little use to create lift." ], "score": [ 9, 7, 7 ], "text_urls": [ [], [], [] ] }
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mqjwbo
What exactly happens to web content outside of the viewport when you scroll? Does the web browser still see it? What parts of the content does the browser ignore?
Technology
explainlikeimfive
{ "a_id": [ "gugjlpz", "gugz2q1" ], "text": [ "Short answer - it depends. But more elaborate is that it depends on how the website was coded itself. By default, browser will load full webpage once you open the URL and that’s what happens in most cases. Some websites though uses approach that would limit this, for example lazy loading - which loads all the content, but images and first loads only the ones in viewport and proceeds load rest afterwards. This will result in webpage appearing to be loading quicker.", "It's still there, stored in your computer's memory until you scroll back to it, otherwise there would be a noticeable delay every time you scrolled up and down a website. There's some cases where a webpage will only load content once you start scrolling, but once it's there, it's pretty much there until you navigate away from that page. The browser (and any plugins or other third party software you allow) can still \"see\" the full content, even if you can't. The browser doesn't ignore any of it, if it's on the page you're trying to view, the browser will try to load it. Pretty much any modern browser contains tools to inspect exactly what is being loaded when and how long it's taking, if you're particularly curious about how any website is loading its content. Edit: \"but once it's there, it's pretty much there until you navigate away from that page\" - realized I probably phrased this wrong. In the same way it's possible for a website to load content at-will, they can also remove content at-will, at which point the browser practically \"forgets\" about it. There's also the case where a website can instead just hide and show certain content, rather than explicitly adding or removing it, in which case the browser always sees it as there, but maybe it's just not visible to you. It ultimately just comes down to how the site is programmed and what (if anything) they're trying to optimize for." ], "score": [ 47, 3 ], "text_urls": [ [], [] ] }
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mqk4xy
How can humans sense each other without ever seeing or hearing them?
Biology
explainlikeimfive
{ "a_id": [ "gugilkh", "gugikse", "guh9e98", "gugoryb", "guh7rxj" ], "text": [ "There's more than just seeing and hearing. There's smell and touch. When someone comes near you they disturb the air around you. That's where smell and touch comes into play. You can feel the air disturbance and smell the slight difference in the air as they approach. It's all very subconscious and instinctual.", "Humans are very social creatures. We are also predator creatures, as well as prey creatures. These three things make it very important to us to know when others are around. Humans lived longer by recognizing when intimate partners, or imminent dangers, are nearby. We are amazing at running, one of our few natural talents, and so we are accustomed to running toward prey and away from predators. If another human is near that isn't familiar, it was advantageous for us to expect to run away or run toward it. The feeling of \"being watched\" saved our skins more often than it hurt us, and so it is now our instinct to assume. Even though our sense of smell isn't that great, it's still really sensitive. Same goes with our sense of touch. Pheromones and being able to sense the air shifts nearby are very important survival traits, despite not smelling as well as a dog or feeling as well as a cats whiskers.", "People can actually sense the change in air pressure from a person being around. You feel them with your ears", "This was actually asked the other day, but I can understand how it was missed. I'll link to my comment from before, but you're probably still hearing them, even if you don't realise it! Or rather, you hear the acoustic shadow where they are. URL_0", "This is going off of general understanding of how intelligence might work. You don't need to do any logical thinking to understand where an object is, it's a \"feeling\" that should be innately available to the brain because there are structures that are meant to support it. The brain also learns to track things that are out of direct sight, the ability is called \"object permanence\". Babies develop it within months and many animals have it too. You can feel the object is there without being able to see it because your brain is activating itself in a similar way to the way it would if you could actually see it. Your conscious brain is preceeded by layers of filtering that decide what's important to pay attention to and what isn't. Filtering helps to discard noise and signals that you just don't need, so you can actively process other things unimpeded. The final layers of filtering are crucial in deciding what you are thinking about right now. Parts of your brain activate in response to your senses without needing to go through all of the filters, by being directly connected. This is why you don't need to actively think in order to recognise an object you see, the image appears to arrive at the same time as you know what it is, along with the feeling that it exists. Your conscious thoughts can attempt to manually override and correct these connections (if the logical conclusion is incorrect) but the feeling happens first. The filters are also responsible for filtering memories and other subconscious processes too but these memories will likely also activate other parts of the brain *before* being filtered so that you can recall related concepts and activate important areas of the brain (especially language and speech centres.) So what probably happens when you just \"know\" or \"feel\" that someone is that either a subconscious learned process is predicting that someone exists nearby based on your current thoughts/memories and you're assigning the object permanence feeling without needing to actively think about it *and/or* you are picking up on subtle signals through your senses that are triggering the same response, but the causing signal is being filtered out because it is otherwise not interesting and only the \"feeling that a person is there\" is noticed. The response may feel consciously strong because social stuff is important, so it might tend to dominate the later filters." ], "score": [ 25, 17, 7, 7, 3 ], "text_urls": [ [], [], [], [ "https://www.reddit.com/r/explainlikeimfive/comments/moasis/eli5_why_are_we_able_to_sense_the_presence_of/gu2ruuc?utm_medium=android_app&utm_source=share&context=3" ], [] ] }
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mqk83o
Night Vision Goggles
Technology
explainlikeimfive
{ "a_id": [ "gugiwxf", "gugisfb", "guhzagi" ], "text": [ "As I recall, they use infrared light and digital imaging. Infrared is just outside of the visible spectrum and thus it doesn't light up the darkness as far as the naked eye is concerned, but it can register on digital cameras and be output by a screen as visible light.", "It just has a camera lense that sees the tiny bit of light, way better than your eye, then a computer that enhances that light by however many light units, then the display presents you with that new enhanced image.", "There’s a few different kinds. “Image intensifier tubes” are the ones we invented back in the 60’s and have a few layers: the first layer gets hit by light, and that later makes some free electrons out the back into a vacuum in the middle of the tube. In that middle section, they apply a voltage and speed up the electrons so that they slam into another layer, one coated with a material that glows brightly when the sped-up electrons hit it. So a little bit of light makes some electrons, which get turned into really fast electrons, which get turned into bright light. Some are just really, really sensitive cameras with a normal LCD display for you to look at. They all tend to utilize infrared light, just out of our visible range but what is actually pretty prevalent in nighttime illumination from stars and the moon. Thermal vision is entirely different. That uses light of a much, much longer wavelength and is based on how warm things are. Both thermal vision and night vision can help you see in the dark, but they give you very different pictures." ], "score": [ 5, 3, 3 ], "text_urls": [ [], [], [] ] }
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mqka62
What happens to wavelengths larger than Earth?
I was wondering if a wavelength the size of the solar system or the universe can exist, and if so, would it propagate forever or "collapse" / be detected somewhere along the wave?
Physics
explainlikeimfive
{ "a_id": [ "gugjnre" ], "text": [ "There are wavelengths larger then the Earth. In fact we are using such waves for communication. They are used by mining companies, submarines and secret military bases. Firstly because they are able to penetrate seawater and rock but also because they are very hard to triangulate. These are both properties which is scaled with wavelengths, hence the large waveletngths. Such waves are also created naturally by for example earthquakes and lightning and also cosmic events such as solar flairs. Waves at these large wavelengths does not behave much differently from those at shorter wavelengths so they will propagate forever. We are able to detect signals from far outside our solar system." ], "score": [ 14 ], "text_urls": [ [] ] }
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mqky32
How are sex hormone levels (Testosterone or Estrogen) maintained in the body? I have heard of something called active level and overall level. What role does that play into this?
Biology
explainlikeimfive
{ "a_id": [ "gugysux" ], "text": [ "The male gonads (testes) and female gonads (ovaries) are embryologically from the same origin, and they are under hormonal control which share similarities. In the testes, Leydig cells produce testosterone. In the ovaries, granulosa cells produce estrogen. Also, fat cells produce estrogen. The testes and ovaries produce these sex hormones under control of luteinizing hormone (LH), which is secreted from the pituitary gland. This hormone, in turn, is controlled by gonadotropin releasing hormone (GnRH) which is secreted from the hypothalamus. In the female, ovarian estrogen production is quite complicated, as you know it happens [cyclically]( URL_0 ) and in phases, in which progesterone also plays a role. Total sex hormone is different from free sex hormone. The free sex hormone, is the fraction of sex hormone that is not bound to sex hormone binding globulin (SHBG), and is therefore biologically active." ], "score": [ 7 ], "text_urls": [ [ "http://www.old-ib.bioninja.com.au/_Media/menstrual-cycle_med.jpeg" ] ] }
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mql6ct
Why are things more prone to breaking when changing temperature?
My personal irl example being a glass smoking pipe. After smoking a bowl in my decently cheap glass pipe, I didn’t wait very long to run it under some water to clean out and dry off in between bowls. I then tapped it a bit against the porcelain sink to try and get some of the remaining residue out (rookie mistake to be sure, but I was high) and the glass just cracked. A whole chunk of the pipe was missing in an instant. It was a very light tap and something I’d done many times before without causing damage, just never right after a drastic temperature change like that. What is the reason for this?
Chemistry
explainlikeimfive
{ "a_id": [ "gugsfbm", "gugsgcz" ], "text": [ "In essence, all materials either expand or contract when they change temperature. Mostly they expand upon heating and contract upon cooling, but there are exceptions to this rule. If a material is rapidly heated or cooled, it will expand or contract rapidly, which reduces their integrity and causes them to break.", "If you heat or cool a brittle material like glass quickly, the outside temperature will change almost right away, while the internal temperature will be pretty close to the original. Glass also shows thermal expansion which means that the glass will also expand and contract at different rates, creating internal stresses which the naked eye can’t see. Because it is a brittle material it has quite naturally some microcracks in it which will make shattering it pretty easy. So when the extra internal stress caused by the heating and cooling is combined with internal stress from production (also caused by this cooling and heating), it will sometimes burst on it’s own, sometimes it still needs a tap. Allowing things you heat and cool a lot to do so more gradually should stop this from happening. There is a way around this, through a process called annealing. This means that the glass is heated to a high temperature below the melting point. It is then kept there for quite a long time, which will make the internal stress from production disappear. It’s a time and energy consuming process, so a product which is decently cheap likely did not go through it." ], "score": [ 6, 4 ], "text_urls": [ [], [] ] }
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mql6ts
How do nuclear reactors work?
Technology
explainlikeimfive
{ "a_id": [ "gugp8gv", "gugofkx" ], "text": [ "Uranium atoms are pretty fat, compared to other atoms. Think of a drop of water on a table. You can keep adding little drops to it, but at some point it gets too big and breaks apart. This is like uranium atoms. We can fire bits of atoms into them, and they burst. The thing is, this bursting produces a lot of energy. It also fires off more bits of atoms, that can hit nearby uranium atoms and make them burst. *These* atoms fire off other bits that break even more apart, and so we get a runaway chain reaction. In nuclear reactors, we use carbon graphite (pencil lead) rods to block some of these bits of atoms. This slows down the chain reaction, and stops it from running away. Meanwhile, we catch the energy that gets released with water. This heats the water up, boiling it, and turning it to steam. The steam goes through vents, which lets it turn turbines, generating electricity. Then, we use big towers to condense the steam back in to water to use again.", "When uranium decays over time it produces heat,heat makes steam,steam makes the turbines spin,turbines produce power due to induction ,the chimneys cool the steam,water comes back cycle repeats." ], "score": [ 6, 3 ], "text_urls": [ [], [] ] }
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mqlolh
- Is it true if someone gets a Spinal Injury they will have an erection? If that is true, why is that?
Post
Biology
explainlikeimfive
{ "a_id": [ "gugs8ob" ], "text": [ "The spine carries and protects your nerves so any damage to it and nerves can either stop working or even send the wrong signals. With the normal flow of nerve signals disrupted the signals can instead be sent back down to the original nerves causes twitching or muscle cramps or priapism (persistent erection). Priapism is usually pretty painful and not connected to sexual arousal and is a very rare complication of spinal cord injury. The common outcomes would be either paralysis or recovery." ], "score": [ 4 ], "text_urls": [ [] ] }
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mqlve9
Why do deer get startled by the smallest noise but when a car is coming they freeze?
Biology
explainlikeimfive
{ "a_id": [ "gugsh1p", "gugrrlr", "guhhhk2" ], "text": [ "Especially when it's dark they get blinded by the cars lights. Then it becomes hard for them to track the lights movement. So they can't see anything but bright blinding light and freeze up because it would also be very dangerous for them to run away blinded because of the uneven ground that cauld easily break their legs if they don't see where to step. If it's just a noise there instinct kicks in and they flee. No instinct reactions evolved for sudden bright light though.", "Because a) they learn eventually that the normal behaviour pattern of cars is to \"pass by really fast, over on that awful hard ground over there\", and b) have noticed that it seems to work pretty well, from a survival-evolution viewpoint to not move any when the car moves past.", "This is how evolution has made them. Cars moving on predetermined paths and *not* wanting to hit them are a very recent thing from the standpoint of biological evolution. The deer are doing the sensible thing - they see a predator approaching fast and freeze to make themselves harder to spot. When the predator (wolf or mountain lion) is really close, they spring and jump across its path to confuse it and make it trip over its legs due to momentum, getting a headstart. Doesn't work with cars at all." ], "score": [ 12, 5, 3 ], "text_urls": [ [], [], [] ] }
[ "url" ]
[ "url" ]
mqlxm1
What is the difference between espresso brewed properly and a whole lot of instant coffee powder with water? Aren't they both essentially concentrated coffee?
Other
explainlikeimfive
{ "a_id": [ "gugwpe9", "gugrpj1", "guhhiro", "guhp4m8", "gugsnoo", "gugse4o" ], "text": [ "So, instant coffee is freeze dried. It is first brewed, either by immersing the beans into water, or by forcing water through them, and then it us freeze dried. This is done by finding the sweet spot of temperature and pressure so the water goes from solid to gas without it boiling off. This process means the coffee is not burnt or scorched from boiling it, and the resulting coffee residue is very porous, so it will dissolve really easily when water is added back. Espresso is made by forcing water through ground coffee beans at high pressure to get the shot of espresso. The difference between these two processes is that there is a lot of things that are done to the instant coffee before it arrives in the store, and a lot of time as well. You can get roasted coffee beans, or even roast them yourself at hime, grind them, and then make yourself an espresso. It will be a lot fresher than the instant coffee, and will likely have more complexity, because it has not been done on an industrial scale. As to what you prefer, that is up to you. I find instant coffee to have an unpleasant gravy-like taste to it, and am willing to spend the extra time to have freshly ground espresso. Others will find instant coffee perfectly palatable, which is perfectly fine, as it is all down to preference.", "this is kinda like asking what's the difference between microwaving a steak and giving it a good cast iron sear the method you use to achieve the end result matters", "FLAVOR. There are many, many flavor components in coffee. The freeze-drying process results in the loss of many of them. That’s why freeze-dried coffee tastes bland or processed compared to a freshly pulled shot of espresso. Incidentally, Starbucks’ freeze-dried coffee ain’t that bad, because in addition to freeze-dried coffee they’ve added some “micro-ground” roasted coffee beans to add (back) extra flavor and body.", "Much like a lot of frozen or dried / canned goods, certain \"[volatile organics]( URL_0 )\" and other flavour-carrying components of the coffee don't survive the process intact, whereas grinding a bean and immediately making a fresh cup of coffee from it gives them no time to escape or oxidise or otherwise break down or get lost. It's a little bit like how fruit & vegetables go mouldy if you leave them, wine goes corked (and turns to vinegar) if air gets in, etc. etc...", "They are not made from the same product. Well they are but with more steps. Espresso is made by basically pushing hot water across ground coffee beans and into your cup. From here you ad milk in different quantities or methods to get the particular coffee you ask for. Concentrated coffee is made initially by pushing hot water across coffee grounds but at an industrial scale. From here it's dehydrated, basically boiling off the water then collecting the residue grinding it up and putting it into jars for distribution. Espresso fresher and less processing steps. Instant coffee much more processing, possibly additives, industrial scale.", "The preparation is the difference. And if you take a cup of coffee and a cup of espresso the espresso has more caffeine. But no one in their right mind is drinking the same amount of coffee as espresso. Their serving sizes are vastly different. 1 shot of espresso has roughly half the caffeine a cup of coffee has. Like someone else said. It’s similar to taking a piece of meat and cooking it properly on the stove/oven/grill/etc vs doing it quickly in the microwave. The time it takes for things to get properly heated/ground for an espresso is substantial compared to what a regular cup of coffee takes." ], "score": [ 192, 22, 7, 7, 3, 3 ], "text_urls": [ [], [], [], [ "https://en.wikipedia.org/wiki/Volatile_organic_compound" ], [], [] ] }
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mqn3nr
Why do some plants have fuzz (on their stems/stalks)?
For example the flower stalk of my sundew, and on the newly sprouted tomato plant. (Not my picture but just to clarify what I mean: [ URL_0 ]( URL_0 ))
Biology
explainlikeimfive
{ "a_id": [ "guh0354", "guhe465" ], "text": [ "The hairs are called trichomes and often serve multiple functions, but the major one is a deterrent to being eaten.", "Tomatoes are actually carnivorous and use those tiny sticky hairs to trap insects. [ URL_0 ]( URL_0 ) Insects that get trapped die and eventually become fertilizer for the next generation of tomato plant." ], "score": [ 7, 5 ], "text_urls": [ [], [ "https://www.telegraph.co.uk/news/earth/wildlife/6727709/Tomatoes-can-eat-insects.html" ] ] }
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[ "url" ]
mqnqww
What are wavelengths and how does it relate to color?
What exactly are wavelengths, and how do colors have wavelengths? What exactly is a color?
Physics
explainlikeimfive
{ "a_id": [ "guh1dvh", "guh16dm", "guh1r5i", "guh1bnz", "guito80" ], "text": [ "> What exactly are wavelength? The distance between two crest of a wave. Imagine an ocean with waves. There are high points and low points. The wave moves forward, but the distance between the high points stays the same. This is the wavelength. > how do colors have wavelength? Color is just light, and light behaves like a wave. Sort of. As light moves through space it has high energy areas and low energy areas which can be measured just like the area of high water and low water with an ocean wave. > What exactly is a color? Color is just how our minds perceive different wavelength of light. The same way our hears perceive the difference between high frequency and low frequency sounds, our eyes perceive the difference large wavelength and low wavelength light. Our brain then interprets that as color.", "Visible light is a spectrum of Electromagnetic waves. Everything from X-Rays to Radio are just electromagnetic waves oscillating at various frequencies, and our eyes are able to detect a certain subset of those frequencies (because all EM Waves move at the same speed there is a direct relation between a waves frequency and it's wavelength). The wavelengths we are able to perceive range from around 380nm to 760nm. Depending on what wavelength the light has we see it as a different colour, for example 400nm would a deep blue, with 700nm being red.", "There is an interesting episode of Radiolab called \"Ripping the Rainbow a New One\" that deep dives how our eyes perceive color. Highly recommend.", "The light is an electromagnetic wave, a special way that an electromagnetic field can spread through space. In some sense it works kinda like a sound wave, but instead of air pressure vibrations you have an electric/magnetic field vibrations. You can measure its wavelength, i.e. distance between the peaks of the same wave. So, the light itself only has a set of wavelengths. But your eyes have three pigments inside, each more sensitive to a certain part of possible wavelengths. The proportion of their reactions to the light is what you perceive as color, for example, if the first one gets a strong response while others hardly see anything, it will be perceived as red. This way, each individual visible wavelength has its own color (if you arrange them side by side you will get a rainbow), but you can also get additional colors by mixing wavelengths together.", "Hi Farid, In physics, light is a type of energy and it is in the form of electromagnetic radiation. The speed of light is approx 186282 miles per second. Electromagnetic radiation is a combination of electric and magnetic. These are classified by wavelength into radio waves, microwaves, and infrared signals. Here wavelength of signal means at what distance the signal shape repeats. When the wavelength is within the visible spectrum, then it is known as visible light. Light is measured in terms of wavelength or frequency. A human eye can respond 380 – 740 nanometers range of wavelength. In terms of frequency, the values will be 430-770 THz. A light can emit at different wavelengths. Here is the visible light spectrum : From 400 to 700 nm approximately The colors of the spectrum of light are violet, indigo, blue, green, yellow, orange and red (VIBGYOR). These are the basic colors and from these colors, by mixing together we can find the other colors which are not in VIBGYOR. So, the colors having mix wavelength values. Each color has its own wavelength. some wavelength values of VIBGYOR colors : Purple : 400-400 Blue : 460-500 Red: 620-720 From the above information, we can say that the wavelength of violet light has the least value and the wavelength of red light in micrometers has a higher value than other color wavelengths." ], "score": [ 38, 5, 3, 3, 3 ], "text_urls": [ [], [], [], [], [] ] }
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mqoh9l
Is there a difference between being thirsty and dehydrated? Like scientifically, biologically - by the time you notice that you are thirsty, are you already dehydrated?
Biology
explainlikeimfive
{ "a_id": [ "guh7viu", "guhl22d", "guhjod7", "guho679", "guhpptl", "guhwo7v", "guhrp7m", "guhx284", "guhvi88", "guhql78", "guj6uqs" ], "text": [ "Yes. Dehydration is a medical condition in which you have less than an adequate amount of water. You can be thirsty without being dehydrated and if you weren't you'd probably become dehydrated because you'd be unlikely to drink unless making a conscious effort to do so at regular intervals. Thirst is just a sensation, like being tired or such. Obviously you'd be likely to be thirsty if dehydrated, but thirst also triggers regularly before dehdration to keep you drinking to *prevent* dehydration. Think of it like this: you want to drive somewhere but you're kind of low on gas. If you can make it there and not have to fill up, you might consider stopping anyways just to top off. This this thirst. If you plan a drive and determain you don't have enough gas to get there,that would be akin to dehydration. Its phydically not enough, vs just maintaining. Either way, you consider stopping for the gas, but if you're low enough, you won't make it. Thats the difference. Edit: thanks for the ~~silver~~ awards! Edit: jeez! This really blew up, i can't believe how many awards it got! Glad I was able to help anyone!", "The 'if you feel thirsty you are already dehydrated' thing is a myth spread by drill sergeants and gym teachers. A number if things can trigger thirst, including but not limited to dehydration. Signs of dehydration are nausea, headaches, dry mouth and throat, reduced blood pressure, dark urine. The tl;dr is you should drink when you are thirsty- not force yourself to drink when you are not. Edit: To clarify, if you have symptoms of dehydration other than thirst you totally should have a glass of water even if you don't want it. Sometimes your body is weird like that.", "The purpose of thirst is to prevent dehydration. Some may claim that it's the first sign of dehydration, but I feel that makes the definition of dehydrated too broad to be useful.", "Medications that cause dry mouth - I take some of these - make people feel very thirsty because the mouth does not have enough saliva. When I have these symptoms I could drink water non-stop and still feel thirsty.", "Aiight so I don't understand something here. If the healthy thing for your body is to drink a lot of water (a gallon a day, which just seems absurd), but folks here are saying \"don't drink water just to drink water, only drink if you are thirsty\", those two things do not seem to work together. I try to drink a lot of water. I can normally get close to drinking 3L of water per day, but often I am just finishing off a liter of water before a meal (to try to avoid overeating). I can say, though, I am definitely not \"thirsty\" every time I drink, and if I only drank while thirsty, there is no way I'd be able to drink a gallon (or not even) a day. So ... what is the proper move? Drink a lot of water each day OR only drink when thirsty?", "I read somewhere recently that while the two are separate, thirst is VERY easy to ignore. Thirst comes first, then dehydration. When you’re busy doing something and don’t want to go grab a glass of water or tell yourself you’ll grab some I’m 10 minutes, you’re essentially training yourself to ignore the “thirst” signal your body is sending. Pretty soon you kind of just ignore the signal until you remember you needed a drink and you end up dehydrated. Similar to how you “forget” to eat or suddenly your not hungry anymore. You learn to ignore the signal for food your body is sending.", "Here’s the thing though. I’ve always thought millions of years of evolution wouldn’t leave me feeling ok and not thirsty if I was dehydrated. But am pretty sure I drink a glass of water a day (at most) and the rest is coffee, tea and Diet Coke. This is hardly the 5 litres a day or whatever stupid amount am supposed to drink...", "Thirst is regulated by two things: the volume of fluid in your body and the balance of salts/electrolytes in that fluid, mostly sodium. You have sensors/receptors in certain areas of your body specifically tuned to each. If the volume receptors sense that you have less fluid in your blood stream, they will release signals to other parts of your body to change how your body balances water and salts so that you retain more water and pee out less. If your sodium level is way out of balance, other signals will try to regulate your salt levels. Since water and salt really like to follow each around, it’s not super clean and regulating water levels oftentimes means some changes to salt levels, with a few exceptions. One of the responses to these signals is behavioral: thirst. You feel the behavioral urge to drink. Side note: there are certain behavioral problems wherein a patient drinks and drinks and drinks if they have access to water, and can do so to the point that they can dangerously drop their salt levels and suffer bad consequences like seizures. The term for that is psychogenic polydipsia. (Poly roughly means many and dispsia roughly refers to drinking). Dehydration refers to having less than the necessary amount of fluid volume in your body. You can be dehydrated with low sodium levels, normal sodium levels, or high sodium levels. Depending on how intact and functional your thirst regulators are, you may or may not feel thirsty, or if you’re unconscious or otherwise altered, you may not be able to drink anything despite your body trying to tell you too. Your body goes through a certain amount of fluid every day just taking care of its basic functions. You get fluid from drinking but also from the foods you eat that have liquid. Healthy people with functioning kidneys should drink when they’re thirsty. If it’s hot outside or you’re doing something active, drink a little bit more. Trust your kidneys. If they’re healthy, they know what to do better than some arbitrary fluid goal. Edited to add: since I didn’t say it outright, to get to the heart of your question. Thirst is a behavioral response/feeling that is most frequently driven by overall fluid balance, but which can also be driven by other factors, like salt balance. Dehydration is a physical state of low body fluid status compared to where it needs to be to support your body’s internal functions.", "I’m pretty sure thirst is just when your mouth and throat feel dry but dehydration is when your body can’t perform normally due to lack of water", "Our \"thirst center\" in our brains doesn't always work properly. There's a lot of hormones that balance your fluid status, and any number of disorders or stresses can throw this off. Elderly people are especially vulnerable to dehydration because their brains don't always tell them they are thirsty, so they don't drink. If your thirst center worked perfectly, all the time, you wouldn't get dehydrated. There's also a difference between dehydration (loss of H2O alone) and hypovolemia (H2O and salt loss).", "If I need water I’m dehydrated. If I need a thot’s clapping cheeks grinded up I’m thirsty" ], "score": [ 6592, 433, 389, 72, 52, 39, 14, 12, 6, 6, 3 ], "text_urls": [ [], [], [], [], [], [], [], [], [], [], [] ] }
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mqoldo
Why do islands tend to have more birds than mammals?
Why do islands rather fewer non bat land mammals? For instance, Hispaniola(Haiti/DR) is known for only two native land mammals but several dozen endemic birds?
Biology
explainlikeimfive
{ "a_id": [ "guh62c2", "guhdy7b", "guhq74j" ], "text": [ "Islands are small and mammals require x amount of landmass and food. Birds are dramatically smaller, they need less space, food and can go not only anywhere on the island to forage/hunt for food, but can fly to other islands for more nourishment. Their size and ability to travel makes them better suited for island life and as a result, they produce more with their higher sustainability.", "It’s a lot easier for birds to fly from island to island — birds often migrate across wide swaths of the globe — than land animals to swim or otherwise island hop.", "Birds have these things called wings that allow them to fly... Now I'm adding a second sentence so that the automatic moderation bot doesn't remove my post for being one sentence long. But seriously, what did you think was the reason?" ], "score": [ 13, 3, 3 ], "text_urls": [ [], [], [] ] }
[ "url" ]
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mqpfds
What makes internet faster or slower?
What makes internet speeds faster or slower? How do companies improve on internet speeds?
Technology
explainlikeimfive
{ "a_id": [ "guhi2cn", "guhapcr", "guhbs6c" ], "text": [ "It’s really just a function of plumbing, though digital. For example, the volume of cold water coming out of your bathroom faucet depends on the size of the spout on that faucet, the pipe from it through the house, the pipe from the house to the street and so on to the source. It also depends in whether or not other faucets in the same house are on, and to a similar extent faucets in other houses in your neighbourhood. If you want more water in the shower, you can buy a bigger faucet, but will require larger pipes through the house to increase the flow. Eventually, larger pipes in the house will exhaust the flow from the street and you will need those upgraded as well which requires the water company to invest. Internet is much the same. Each interface (faucet) has a size and if you increase the size at the edge (your house) eventually you will need upgrades in size all through the connections back to the source(s). Internet providers are constantly adding capacity and chasing slowness that comes from imbalances in edge capacity versus core and changes in usage patterns (popular content sources). Now consider all your neighbours install high volume sprinkler systems and have big pools that need filling in the spring and you get an idea of what IPTV and Netflix/Youtube etc have done to internet providers and how hard (expensive) it has become to ensure things are “flowing”. Just some rambling from your local digital plumber :)", "Infrastructure, mostly. There are different types of cables which can carry data at different rates. Companies improve speeds by upgrading equipment and using more/better cable. What makes internet slow or not work at all is either nearing capacity for equipment (data is moving across cables/equipment as fast as it can and everyone is trying to use it at once) or physical damage issues (someone did some digging and broke a cable). There are lots of other nuances like traffic management and different places things can get bottlenecked but that's the gist of it.", "For the end user, its almost entirely software settings on the ISPs equipment on the street, it sets the maximum bandwidth that the router on the street will let you use. The max bandwidth you can use is limited by the quality of the connection between you and the router on the street but its a pretty short run so a standard coax cable can support really high speeds over that short distance How much total speed that router can hand out to the people on your block depends on its connections back to the main office. If they provide more fiber optic cables or channels on the same fiber then it can send more data between itself and the main office so it has more bandwidth it can offer you. They can increase the channels by upgrading the sending and receiving devices to ones that can pump more data down a single fiber." ], "score": [ 33, 14, 3 ], "text_urls": [ [], [], [] ] }
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mqpntq
How are more than a hundred million transistors Fitted on an area of about a millimetre Square?
Technology
explainlikeimfive
{ "a_id": [ "guhbpeb", "guhdccn", "guhvjts" ], "text": [ "By making them *very* small. The \"Node size\" chip manufacturers talk about is based on a measurement of how 'big' the transistors are (the exact meaning of this measurement varies between manufacturers). Usually this is measured in nanometres, i.e. one billionth of a metre. -\"Hey! That would mean we need one metre to fit one billion\" you might think; but consider they're not on a line, but on an area. EIDT: To add, the manufacturing process involves shining light onto the material, and having the material brake down from the light. This is how you can make billions of nanometre-sized things cost-effectively. It's called \"photolithography\"", "[This is a transistor]( URL_2 ) and the \"schematic\" of a transistor. So what you see is mostly the plastic outer cover and the big metal leads, but the actual \"transistor\" device inside can be extremely small. This is because a transistor is made by taking a wafer of pure silicon, and contaminating areas on it with atoms with extra electrons or fewer electrons (for example aluminium has 3 outer orbital electrons, phosphorus has 5, so they are +/-1 compared to silicon's 4 outer electrons). The process is called [doping]( URL_0 ), and the point is to create adjacent \"zones\" with \"extra electrons\" then \"fewer electrons\" then \"extra electrons\" again; this combination of 3 zones is what a transistor actually is. So because a teaspoon of material generally has [10^20 ]( URL_3 ) atoms in it, and you don't need that many to make a transistor, miniaturization is very much possible, down to a scale where the doped regions are so small that you can cram millions of them on a [wafer of pure silicon]( URL_1 ).", "By carving them with light. You know how a tiny photo negative can be blown up into a giant photo? Well the reverse can be done with a relatively large image of a processor design and then using light and lenses to shrink the image onto a smaller space. If you shine this image onto a light sensitive material you can carve out the paths for transistors, pour the transistor material on top and then more or less sand off the excess. When done the material you want is only left in the areas where the light from your \"negative\" was projected, repeat this process with a different negative for each type of material you need and you can start to build a complex circuit at a very tiny scale. This takes an incredible amount of precision to pull off and due to the size difference in the machines vs what they are producing tiny improvements in the machining can have relatively large improvements in the efficiency of the processors they produce. However now we are making things so small that weird quantum mechanical effects are starting to cause issues so we won't be able to go much smaller without coming up with a whole new material to build processors on." ], "score": [ 27, 9, 5 ], "text_urls": [ [], [ "https://en.wikipedia.org/wiki/Doping_\\(semiconductor\\)", "https://i.ebayimg.com/images/g/W88AAOSwcABeSM7I/s-l300.jpg", "https://cdn.sparkfun.com/assets/learn_tutorials/1/9/3/intro.png", "https://en.wikipedia.org/wiki/Avogadro_constant" ], [] ] }
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mqqu9s
Sperm are often referred to as “swimmers.” What exactly are they swimming through? Are the uterus and Fallopian tubes filled with liquid, or empty?
Biology
explainlikeimfive
{ "a_id": [ "gui8a27", "guhjg58", "guhp7m4", "guiigir", "gui1fvv" ], "text": [ "They are travelling through cervical fluid. When a woman ovulates and is most fertile, her cervical fluid becomes clear and mucous like, perfect for sperm to travel along. The consistancy of cervical fluid changes throughout the month and becomes less easy for said swimmers to travel along when she is not fertile. The cavities do contain these cervical fluids but it's not as much as you think, its just enough to coat the surface of the womb. Aside from this, it is empty.", "Both uterus and Fallopian tubes are filled with liquid. They're even directly connected to the peritoneal cavity, and trust me, you don't want to have any air in there.", "People have already answered, but I wanted to add that the semen don't really do much of their own swimming. The vagina and cervix assist by pushing the sperm toward the fallopian tubes/uterus", "OP please talk to your physician, midwife, or find a reputable gynecological website for answers. The misinformation in this thread is not going to help and facts matter when you’re trying to conceive. Good luck!", "Almost nothing in our bodies is empty. Yes the uterus and fallopian tubes has some fluid in it." ], "score": [ 238, 136, 64, 22, 6 ], "text_urls": [ [], [], [], [], [] ] }
[ "url" ]
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mqr8vb
How do video games determine if a button is held or pressed without there being a noticeable input delay?
So, I've wondered for a long time how video games determine if a button is held or just pressed for 2 different actions in games without any noticeable delay. To me, even very slight delays are extremely obvious so I'm just not sure. Sorry if there is an extremely obvious answer, I've just always kind of wondered.
Technology
explainlikeimfive
{ "a_id": [ "guhm5h1", "guhlrsh", "guhoynp", "guhmp5m" ], "text": [ "From a programming standpoint, you essentially get a button down and button up command. So it's not constantly saying BUTTON PRESS when you hold down a button, the controller knows that the button is in a down state and sends the console/PC that button down command when you first press the button, then when the button is released it sends button up. From there, controllers tend to have input lags in the 3-30ms range, which is well beneath your normal human response time of ~80-100ms.", "When it comes to milliseconds, most people don’t notice. There are people who will complain about any input lag but with modern technology and the speed in which the signals are transmitted to the system, there isn’t much of an issue. From there the system can kick off different threads to handle multiple inputs. If you’d like to see an example of noticeable input lag lookup google stadia.", "Simply put, the computer is WAY faster than you. Let's go back to early days, slow computers, the old Atari, 1 MHz. Pressing a button sent an electronic signal over a wire to a controller chip, which caused a certain value in memory to be set. This happens in microseconds (millionths of a second). Your game is looping, and every several milliseconds (thousands of a second) it looks for joystick input by reading that memory location. This is far faster than you can react, so it seems instant to you. These days there are layers between that. Pressing a button causes a signal to be sent over a wireless connection, where it is is processed by the wireless controller and presented to the operating system, which in turn presents it to the game as an event. The game is then told to react a certain way whenever it receives a button press event. But with our faster computers, this is still much faster than you can react, so it still seems instant to you.", "They sample input very rapidly...in most games this means sampling input every frame. So if you are running 60 FPS, that means sampling input 60 times per second - or every 16.67ms (roughly). That's much more quickly than average human reaction times. As for checking for a press vs a hold, that's going to depend on the specific design choices of a game. If, for example, you have a charged sword attack that you have to hold the button for 1 second to trigger, the game will read input for 60 frames (assuming stable frame rate) and if the button is held the whole time it'll trigger the charged attack. But, how do you keep animation smooth if the same button triggers an instant attack? You simply build your combat system with that in mind. When a user presses a button you *start* counting frames (time, technically) until it's released. If that button is released at any time before 1 second (for the charged attack), you *immediately* trigger the instant attack animation. The thing with button presses causing special actions, is they only cause the action after a certain amount of time. So if the button is released before then the game can immediately ignore the \"hold\" action and trigger the \"press\" action instead." ], "score": [ 19, 3, 3, 3 ], "text_urls": [ [], [], [], [] ] }
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mqrf9e
What is the difference between "high quality" audio files and "low quality"
What is the difference between "high quality" audio files and "low quality" what are you supposed to be hearing in these higher quality tracks that isn't in the lower quality ones? for example i tried this test URL_0 and it might as well have been the same file 3 times. there is no difference between all the files to me.
Technology
explainlikeimfive
{ "a_id": [ "guhotfy", "guhuj9g", "guhmv0z" ], "text": [ "Compression. Mp3 compresses the sound file which is lower quality. If the sound itself has peaks of 100 for example, to truly experience the sound as if you were there, it would need to be saved exactly as it was played. If you record it as an mp3, it will compress it, and those peaks will shrink down, let’s say to 50. So every part of that recording will be compressed down, so that that 100 which is now 50 will sound normal. This sacrifices quality, but it also makes the file size way smaller. But really unless you work professionally in sound and have expensive equipment you’re probably not going to notice much difference", "So from a recording perspective, there's a thing called bit depth and sample rate. These are two of the major factors in determining the quality of an audio file. Bit depth is the number of 'bits', which are binary numbers, you have in order to describe something.. which in this case is the sound file you are recording. You can think of bit depth like the resulting accuracy of the sound wave due to the hardwares efficiency at recording, higher bit depth recording enable there to be less noise due to the availability of what's called a noise floor. Noise floor is what's typically referred to as the self noise from the actual recording equipment, so a higher bit depth enables you to basically push the noise down further to inaudible levels and therefore have a cleaner signal. Sample Rate you can think of as how many samples are being recorded a second in quick succession. You can think of this as how older animation graphics painted each frame and played them in quick succession in order to get a detailed moving animation. The same thing for audio, sample rate is how many cuts of the audio we have In order to give a more details picture of the audio. When playing back recordings we maybe compress higher bit depth and sample rates down to a more manageable/ sizeable format. You can find CD quality or better streaming platforms can output audio at 16bit and 44.1khz (sample rate). This is a typical output format you see in most situations as most playback systems will only output this amount of detail. Mastering engineers will typically master tracks and tailor output formats dependent on the playback systems that the song might be played on.", "What device did you use to listen to them? If you're headphones/speakers aren't good enough, there might not be any difference. It's the same as with screens. 200 fps means nothing, if you're screen is only able to produce 60." ], "score": [ 4, 4, 3 ], "text_urls": [ [], [], [] ] }
[ "url" ]
[ "url" ]
mqrj60
Why do we make fake scenarios in our head and hurt our own feelings ?
Other
explainlikeimfive
{ "a_id": [ "guhnrmx", "guhpxpe", "guhrcmd" ], "text": [ "Validation, self doubt, self reassurance, depression, anxiety, loneliness, or simply no reason", "From an evolutionary perspective it might have been useful to prepare for possible future scenarios, so that we don't have to rely only on the problems (and their solutions) that we've directly encountered, but to be also able to proactively prepare ourselves for other possible situations that have not yet happened. Of course, it's also a big source of distress for us. The positive scenarios we image will leave us dissapointed when they don't come true, while the negative scenarios have us constantly worried. But! Some people (even experts in psychology) say that it's possible to get rid of this problem. If you want to learn more, just search for \"mindfulness\" or \"MBSR\".", "Blame the primal reptile part of our brain. We seek the worst in situations so that we can hope for some sort of resolution before it has happened." ], "score": [ 9, 9, 4 ], "text_urls": [ [], [], [] ] }
[ "url" ]
[ "url" ]
mqrju8
When I'm having a shower, although 95% of the human body is not in contact with any hot water, why does it still feel warm in general, even when it's really cold in the bathroom?
Biology
explainlikeimfive
{ "a_id": [ "guhopzh", "guhwqed" ], "text": [ "The air surrounding where the water is falling is going to be much warmer than the rest of the air in the room, especially with a shower curtain closed - creating a semi-enclosed enviornment. Additionally, you're likely rotating your body a bit - any areas of skin that had direct contact with hot water 10 seconds ago are still going to be warmer than those that never had contact with hot water.", "I think it also has to do with humidity in the air. Regardless of how much water is hitting you physically in a way you can see/feel, the spray is much wider. Like, if you hung a shirt in the shower for a while, while it was on but not under the spray, the shirt would still get damp." ], "score": [ 7, 3 ], "text_urls": [ [], [] ] }
[ "url" ]
[ "url" ]
mqslp8
How are digital photos made?
Specifically in cameras with mirrors (DSLR) a photo transferred to what you suddenly see on screen? And is the technology same for all kinds of photography: phone, different cameras, etc.? Thanks
Technology
explainlikeimfive
{ "a_id": [ "guhv8hr" ], "text": [ "Digital cameras use image sensors to take the picture. These sensors are grids of light sensitive components that generate an electrical signal based on the intensity of the light they receive. The components are sensitive to different colors (similar to the pixel layout on a tv screen). When the camera takes a picture it reads the current \"state\" of each one of those sensors. All digital cameras work on this same basic principle. A DSLR is similar to a SLR in that a mirror redirects the image through the lens up to the view finder. When the camera takes the image it moves the mirror out of the way so the image falls onto the sensor instead. In a film SLR the mirror is moved so that the image falls onto the shutter, which then opens and closes to expose the film." ], "score": [ 3 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqsmj6
What triggers or causes labor? Like how does the fetus decide when it’s time to come out?
Biology
explainlikeimfive
{ "a_id": [ "guhy4tg", "guhxsq5", "guia82b" ], "text": [ "Simply, chemicals. There are a few hypotheses: * Hormones from the mother - oxytocin production increases towards the end of pregnancy and triggers contractions (this is actually what the hospital gives you when they induce labour and want contractions to begin). * A protein produced by the baby's lungs has been postulated to trigger labour when the lungs have sufficiently developed to survive outside. This may make sense as the lungs are near the last organs to develop. * Cortisol production in the baby near the end causes a hormonal imbalance of progesterone and estrogen, which has been hypothesised to induce labour.", "This is one of the great mysteries of biology! We aren’t sure. One theory is that the fetus or the placenta sends a chemical message to start the process, but we don’t really know", "The simple answer is hormones. When someone becomes pregnant, the ovaries initally produce hormones that help the feotus grow, then the babies own placenta will also produce hormones to continue the process and so on.. ... at about 9 months when the baby has reached the right amount of development (this is coded into dna) the feotus itself releases a small amount of specific hormones which then trigger the mother to then release more hormones that trigger her labour." ], "score": [ 18, 14, 6 ], "text_urls": [ [], [], [] ] }
[ "url" ]
[ "url" ]
mqt0f8
why aren't more portable devices waterproof by now? It seemed like the direction things were going a few years ago.
Technology
explainlikeimfive
{ "a_id": [ "guhxgon" ], "text": [ "Extra cost combined with not much need. Its a handy feature to have when you need it, but for the most part people aren't trying to use their devices in the rain/water. Waterproofing all of the seams and openings takes extra time and effort which makes manufacturing more expensive and complicated." ], "score": [ 22 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqtf23
Why does the fbi announce who they're investigating?
It only seems to happen with politicians. They announced they were investigating Hillary in 2017 and recently with Matt Gaetz. Aren't they losing their upper hand by letting people know they're being investigated?
Other
explainlikeimfive
{ "a_id": [ "gui0j5h" ], "text": [ "By the time an investigation is announced it's already been underway for quite some time. The Announcement phase is typically after the court prosecutor has decided there is sufficient evidence that wrongdoing occurred. Past that point Legal Holds are issued to the concerned parties and destroying evidence (like Hillary did) is further considered by the court as part of the case. So you may not get nailed on the original charges but you most certainly will get nailed for tampering with the case." ], "score": [ 6 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqtlcl
How does tight back muscles cause eyestrain?
Biology
explainlikeimfive
{ "a_id": [ "gui5ywc" ], "text": [ "The eyes are formed from the same cells that will develop into the brain. Like the brain, eyes require a lot of blood flow. If your back muscles are tight, it often means you're slouching forward and stretching those back muscles too much. Slouching can disrupt the blood flow to your head and eyes, causing vision issues. If you lie on your back and stare upwards at a phone or tablet, does the fuzziness go away? I would recommend getting a full retinal checkup by an eye doctor just to make sure it's not any other issue." ], "score": [ 4 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqtrah
Physically, what is timbre in music? What does timbre *look* like?
Other
explainlikeimfive
{ "a_id": [ "gui4b92" ], "text": [ "When an instrument strikes a note it doesn't just produce a pure sine wave of that specific frequency and that is that. There will be multiple frequencies playing at once. One of them, the note we wanted to play, is the strongest and loudest. That is the fundamental frequency. The other are much softer and are called overtones. Each instrument (or anything that produces sound) will form different harmonics and overtones to accompany their fundamental frequency. The combined effect of all these different frequencies are what we recognize as the \"sound\" of a guitar or \"sound\" of a piano. that sound that allows us to identify what instrument is being played is the timbre of that instrument. In music you may want more timbre for a deeper more complex sound, or less timbre for a cleaner more mechanical tone." ], "score": [ 5 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqtrb7
How do wasps/bees know what parts of an animal to sting?
Am I just not noticing when they try to sting me through my jeans, or is there a way they can tell what's skin and what's protective layers?
Biology
explainlikeimfive
{ "a_id": [ "gui5hyx", "gui4rmb", "guigq8u" ], "text": [ "I'm speaking from a place of being swarmed an unfortunate number of times, because I come from a long line of less than graceful humans who tend to fumble along and find themselves in predicaments. I've had the misfortune of being stung through denim (AND the panties underneath), bathing suit and socks on different occasions. Sidenote: You have not lived until you've accidentally mowed over a nest of ground wasps and they sting your bare toes in sandals and they swell up like little fingerling potatoes. 0/10, do not recommend. \\*Edited to fix my spelling.", "I think they try to sting any part of you. If the sting goes in, there's a good enough chance you'll feel it. Humans \"evolved\" clothes only a few thousands years ago, I don't think wasps' evolution had the time to catch up with it.", "Well they actually are intelligent enough to know your face from your arm. They may be self aware, as ants already show signs of self awareness. If they are familiar with you and know you pose no threat, they are less likely to sting you. I also have tried this on garden ants in my garden. 3 years later, they completely ignore me. I tried to fight them at first by removing their mounds, but now I have taught them to eat the pests in my garden (by feeding them what I want them to eat), so they forage without issue now." ], "score": [ 12, 6, 3 ], "text_urls": [ [], [], [] ] }
[ "url" ]
[ "url" ]
mqtxq8
what is the difference between lucifer and satan?
Other
explainlikeimfive
{ "a_id": [ "gui4dhq" ], "text": [ "In Christianity, they are just synonyms to refer to the Devil. In Judaism, Satan (*Ha Satan*) is the accuser, an angel under the command of God, to accuse wrongdoings of people. The reason Lucifer has been understood to be a proper name of the Devil has to do with the Latin translation of the Hebrew term Helel. This word was understood, by some, to be a proper name for the king of Babylon. It means \"light bearer,\" or Lucifero in Latin. The Latin title became a popular name for this evil figure. When the King James translators rendered the Hebrew term into English, they kept the popular term \"Lucifer\" for the Devil." ], "score": [ 10 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqudi8
What is a "kernel" in mathematic/statistics, and what's the 'trick' it enables?
I've taken grad math/stats courses and used SVM, but this concept never landed for me
Mathematics
explainlikeimfive
{ "a_id": [ "gui7iu0", "guifmuz" ], "text": [ "This is a tough one... A kernel function is a function that transforms points in a lower-dimensional space into points in a higher-dimensional space. So let's say you have points on a 2-d grid at random places around the point x=0, y=0. By applying a kernel function, you could transform them into points on a 3-dimensional box. For example, the new z axis value could just be distance from x=0, y=0. This is useful when you're using linear methods to try and separate two classes that aren't linearly separable in 2-dimensions. So in the previous example, let's say all your points form up in a 2-d circle shape with x=0, y=0 at the middle and all the points of class 1 are in the middle of the circle and all the points of class 2 are at the outside. You can't separate them linearly because you can't draw a line that nicely separates them into two distinct groups. But you can apply the kernel trick by applying a function that adds a 3rd dimension. A simple one like z = distance from the centre (x=0, y=0) would do it. Now your points are in 3d space. And all the points of class 1 which were in the middle of the circle are lifted up much lower on the z axis than the points of class 2, further away from the centre. These points of different classes are now linearly separable because you can draw a 2d plane between the two classes that neatly separates them into 2 distinct groups.", "A kernel lets you organize a bunch of different stuff in a way that you can then separate out and solve. Basically the “trick” it enables is to let you use linear equations and mathematics to solve non-linear problems. Imagine you have a big tangled yarn ball of chargers and you’re trying to figure out which one is actually your phone charger. The kernel in this situation is the process of untangling all the wires so you can start testing which one actually plugs into your phone." ], "score": [ 13, 3 ], "text_urls": [ [], [] ] }
[ "url" ]
[ "url" ]
mqug48
What causes us to feel tired/sleepy? Like what’s the biological process of feeling sleepy
You know how emotions are basically the result of hormones in the brain. Tiredness/sleepiness isn’t an emotion, but is it the result of hormones too or is it something entirely different?
Biology
explainlikeimfive
{ "a_id": [ "gui767c" ], "text": [ "Melatonin is released in your system when your circadian rhythm tells your body it’s time to sleep. This is the chemical that actually makes you sleepy." ], "score": [ 3 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mquj3n
Why do some phones have 108 megapixel cameras, while others stick to 12?
Is there no set in stone way to imprpve picture quality?
Technology
explainlikeimfive
{ "a_id": [ "guic8bu" ], "text": [ "The pixel count of a camera doesn't directly imply superior image quality. The biggest reason is that if there are more pixels in an imaging sensor, the less light reaches to each individual pixel. Dimmer light means poorer image quality. To compensate dimmer light per each pixel, you either need better (more sensitive) imaging sensor (which is very difficult) or just bigger sensor (which is not quite suitable for compact devices like cell phone). For example, old DSLR's (which have much less pixel count than modern phone cameras) have much much better image quality despite far lesser pixel count because the sensors in them are about 30 times larger. Though imo Samsung Galaxies (108 MP) catch much more detail than Apple iPhones (12 MP). Apple might think that such high detail is not absolutely necessary for the consumers. Instead Apple does a lot software tricks to fake images look better." ], "score": [ 7 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqvi8v
How does making a figure 8 with your phone improves it's sense of direction?
Technology
explainlikeimfive
{ "a_id": [ "guie6l1" ], "text": [ "The compass in your phone responds to the earth's magnetic field, but the compass wants to experience the magnetic field changing around it, so it can know which way is which more effectively." ], "score": [ 5 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqvqxo
Why is a chicken soup a go-to move when getting sick?
Biology
explainlikeimfive
{ "a_id": [ "guifsau" ], "text": [ "1.) easy on the stomach 2.) vegetables help with minerals and vitamins 3.) warm and comforting 4.) tastes good" ], "score": [ 22 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqvtu5
Are animals conscious? If so, how does their consciousness differ from from humans?
Biology
explainlikeimfive
{ "a_id": [ "guig5r6", "guifqm1", "guih8ho" ], "text": [ "We don't know, and have no way to tell. In a similar vein, we have no universal definition of consciousness in the first place, we can't be sure if other people are even conscious themselves, and we have no way of knowing if there is consciousness different to those experienced by humans.", "Yes all animals are conscious and awake however are they self aware is the questions of the ages, I for one belive yes they are", "Cool question! I think in western thought consciousness varies by degree on a spectrum depending on brain size. So yes all animals are conscious to a degree. In eastern thought all physical manifestations are the result of consciousness. This topic is widely debated in science and philosophy so there's no definitive answer. Fun to think about tho!" ], "score": [ 15, 5, 3 ], "text_urls": [ [], [], [] ] }
[ "url" ]
[ "url" ]
mqy4qe
What are those things we see while looking at the sky or focusing on something for too long?
It looks like worms, dots, sparks, whatever, and they are translucent. Are they doing something bad to eyes?
Biology
explainlikeimfive
{ "a_id": [ "guivoak" ], "text": [ "These are called [floaters]( URL_0 ). They're little bits of the \"gel\" inside your eye that has clumped up for whatever reason and floats around. They aren't harmful, but in serious cases there are procedures to deal with them." ], "score": [ 5 ], "text_urls": [ [ "https://en.wikipedia.org/wiki/Floater" ] ] }
[ "url" ]
[ "url" ]
mqy5cl
What is a basic intuition for Gödel's incompleteness theorems?
Mathematics
explainlikeimfive
{ "a_id": [ "guj7gus" ], "text": [ "Take the sentence, \"This sentence is false.\" Is it true? Well, if it is, then it's false, so it's not true. So it must be false. If it's false, then it must be a true sentence (it says so itself!), so it's true. Wait a minute...something weird is happening, and you might intuitively recognize that it's because the sentence is referring to itself, from within itself. Godel basically showed that any set of math principles that's sufficiently complicated to do anything interesting with can create the math equivalent of \"This sentence is false.\" And he did it in a general way that you can apply to \\*any\\* (sufficiently interesting) future set of math principles. So you can always create at least one \"statement\" that is neither true nor false, so any math theory is always going to have \"gaps\"...statements it can make that aren't true or false, they're something undecidable. The theory is incomplete. This was enormously demoralizing to a bunch of mathematicians who'd spent their entire careers trying to define the be-all-and-end-all of mathematics that would describe every single true statement of math that could ever be. Godel didn't just prove, \"You're wrong this time\", he proved, \"You can never be right no matter how hard you try.\"" ], "score": [ 5 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqyb2t
When we begin to mine asteroids for their resources, how will scientists know which ones to mine?
Earth Science
explainlikeimfive
{ "a_id": [ "guixovc" ], "text": [ "You’re looking for metallic asteroids - fragments of long-destroyed proto-planetary cores made almost entirely of metals. They’re the rarest type of asteroid because it takes a very specific series of events to create them. To spot them you have to combine spectral data (their surface has lots of iron and little silicon or carbon) and density measurements. Other asteroids are rock, carbon, and ice and are considerably less dense than a brick of solid metal. A metal-rich asteroid will have unusually high gravity for its size, indicating that it’s extremely dense." ], "score": [ 5 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqyl7u
do anti-inflammatories have a limit on how much inflammation they can reduce?
Say you take some for a bad back. Then you're unlucky and develop a sore knee but your back still hurts. Would the anti-inflammatories get to work on both, or would there only be a finite amount of area that they would work on? Like, if you want your knee fixing then you'd have to up the dose, for example. I can sort of understand the principle with painkillers because their mechanism is different but anti-inflammatories confuse me.
Other
explainlikeimfive
{ "a_id": [ "guizg63" ], "text": [ "While an anti-inflammatory is in your system it affects your entire body. It doesn’t get “used up” by one inflammation. If you take some for your back and 4 hours later you hurt your knee, there’s not much left in your system but it will work on both." ], "score": [ 3 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mqzhh2
why can't we drain some water out of the sea to simultaneously combat rising sea levels and drought?
I feel like the answer to this must be really obvious and I must be really as dumb as a 5 year old. But isn't there a way to purify water and take salt out of it and then repurpose it for the land and drinking water? Obviously it would be best if global warming stopped, but is there a reason that we couldn't do these things? Would it only be a question of expense, or are there some other prohibitive factors?
Earth Science
explainlikeimfive
{ "a_id": [ "guj4i87", "guj3kea", "guj3lg1", "gujr52z", "guj56vv", "guja89e" ], "text": [ "Well, we already do. there is more than 15,000 operational desalinization plants globally. **In California alone there are 11 desalination plants, with 10 more proposed. But there are big downsides to making seawater drinkable.** Globally, more than 300 million people now get their water from desalination plants, according to the International Desalination Association. Desal proponents acknowledge the industry must confront and solve some serious environmental issues if it is to continue to grow. Desalination requires vast amounts of energy, which in some places is currently provided by fossil fuels. Kiparsky warns of a feedback loop where more desal is needed as the planet warms, which leads to more greenhouse gas emissions. In addition, there are serious concerns about the damage to marine life from the plant’s intake systems and extra-salty wastewater. There are two types of desalination—thermal, which heats up water and then captures the condensation, and reverse osmosis, which forces sea water through the pores of a membrane that are many times smaller than the diameter of a human hair. This traps salt molecules, but allows the smaller water molecules to go through. Both require a great deal of energy, and greenhouse gas emissions created by the power needed—especially in the Middle East, where fossil fuels generate electricity—are a significant contributor to global warming. & #x200B; Seems like it would likely be counter productive to the overall effort to stop climate change. Sure, we might keep a few cities out of the ocean but it would likely ramp up run away heating of the planet at a much faster pace. & #x200B; if you would really like to learn more read here - [ URL_0 ]( URL_0 )", "It costs a lot of money and takes a lot of energy to purify seawater in any meaningful capacity, to the point that mostly people just don’t want to take that hit. It’s not something that they’d get their investment back on down the road, it’d be a money pit they’d constantly throw money at and at BEST hope to reach a point of minimal losses.", "From what I understand desalination is very very expensive. But I always wondered the same thing about draining water from the sea and diverting it inland to combat rising levels too. Interested to see answers.", "Just want to point out that, whatever water you take out of the sea eventually gets back into it. So you're not really doing anything to help with rising sea level without dealing with melting ice directly.", "It's not dumb, just naïve. There is A LOT of water in the ocean, for context the ice sheet that covers Antarctica averages a **mile and a half thick,** that's an entire friggen' continent with over a mile of ice. When Antarctica melts it'll raise the average global sea-level a mere 8 feet. So any plan to combat climate change via ocean draining would have to find a way put a couple miles worth of water somewhere safe on a massive, like *continent sized* scale. So there is both a financial and technological barrier there. Desalinization is also a problem because it requires a lot of energy (which causes other climate issues) but also doesn't just turn ocean water into drinking water + blocks of salt. The end product is actually a super, super saline brine, like pickle juice on steroids. Even small scale desalinization projects run into environmental challenges with the brine, a large ocean-draining sized plant would be environmentally impossible with any imaginable technology.", "Others have explained desalinization, so I just wanted to crunch a few numbers to illustrate the massive scale of the problem we're dealing with. The deepest open-pit mine in the world is [Bingham Canyon Mine ]( URL_0 ) near Salt Lake City, Utah. It's over a kilometer deep and four kilometers at its widest, covering an area of 7.7 km^2, and it's taken over a century to dig. If we assume for simplicity's sake that Bingham Canyon Mine is shaped like an inverted cone, then it has a volume of about 3.1 km^3. Meanwhile, the oceans cover two-thirds of our entire planet. They cover an area of 361,900,000 km^2 - 47 million times more area than Bingham Canyon Mine. They're rising at a rate of 3.3 ~~cm~~ **mm** per year, which equates to a volume of ~~1,200~~ **120** km^3 annually. Dividing ~~1,200~~ **120** km^3 by 3.1 km^3 shows that the rising seas could fill up ~~387~~ **39** Bingham Canyon Mines every year. In order to halt sea level rise we'd have to dig at least one new B.C.M. ~~*every single day,*~~ ***every ten days,*** along with building the infrastructure to pump six ~~billion~~ **hundred million** gallons of water per minute (more if you count the water lost to evaporation) from the sea to the mines." ], "score": [ 68, 11, 7, 7, 7, 3 ], "text_urls": [ [ "https://www.wired.com/story/desalination-is-booming-as-cities-run-out-of-water/" ], [], [], [], [], [ "https://en.wikipedia.org/wiki/Bingham_Canyon_Mine" ] ] }
[ "url" ]
[ "url" ]
mqzu0s
If honey doesn't expire, would it be possible for a genetically modified food to be created that harnesses that quality?
Biology
explainlikeimfive
{ "a_id": [ "guj69tw", "guj6ehx" ], "text": [ "You don't need to genetically modify anything. Honey doesn't expire because it has a ton of sugar in it that absorbs all the available water, and microorganisms need water to grow. We already use the same principle in things like jelly or candy - or, more directly, in syrup. (And the same principle of removing water is the root of all dried foods, which are too numerous to list.)", "The main reasons for the longevity of honey are its lack of water content and its acidity. Bacteria that fall into it simply dehydrate and die, or struggle with the acid. It's difficult to make a GMO plant or meat that would have the same quality of lacking water, since water is needed for life up until the harvest/slaughter. But we do apply the same principle, dehydrating to preserve, when we make raisins or jerky." ], "score": [ 11, 6 ], "text_urls": [ [], [] ] }
[ "url" ]
[ "url" ]
mr00iq
if you had an unhealthy high fat diet for decades but started eating properly would the fat that was blocking your arteries eventually reduce?
Biology
explainlikeimfive
{ "a_id": [ "guj9ea8", "gujz35u" ], "text": [ "Potentially. According to Mayo Clinic: > Atherosclerosis is the buildup of fats, cholesterol and other substances in and on your artery walls. This buildup is called plaque. > Lifestyle changes, such as eating a healthy diet and exercising, are the first treatment for atherosclerosis — and may be all that you need to treat your atherosclerosis. But sometimes, medication or surgical procedures may be needed. Eating right and getting more exercise can definitely help. It might not stop the problem entirely, but it will absolutely be the first line of treatment.", "Even with aggressive use of cholesterol lowering drugs plaque **reversal** has been the holy grail. There are a few studies demonstrating use of multiple high potency drugs where plaque reversal can be achieved. Lifestyle changes, in strictly terms of lowering cholesterol, are not nearly as effective and probably do not reverse arteriosclerosis. This is not so much an issue if you don't have heart disease. No stenotic arteries, no problem especially if you're (because of your new, clean lifestyle) are not adding on to the plaques. That said there are a number of benefits beyond arresting arteriosclerosis that are gained from eating well, keeping your weight down, and getting regular physical activity. Certainly to live a long life with less risk of disability, a worthy goal." ], "score": [ 12, 6 ], "text_urls": [ [], [] ] }
[ "url" ]
[ "url" ]
mr03ux
What is the explanation as to why people do thinks that tend to make them upset? For example, I love to golf but every time I go I just end up angry.
Other
explainlikeimfive
{ "a_id": [ "guj7uli" ], "text": [ "Wanting and enjoying are separate mental processes. The most visible example of this is drug addition, where the 'wanting' urge remains very strong even when there's no enjoyment from it (and may even be pain). To a **very** rough first approximation, wanting (in the sense of acting to acquire something) is driven by dopamine, while enjoying (in the sense of feeling good once you have it) is driven by serotonin. This is a gross oversimplification, though: exactly how the motivation-and-reward system in the brain works is an active area of research." ], "score": [ 4 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mr0rzi
why do big animals have slow heartbeats and small animals have fast heartbeats?
Biology
explainlikeimfive
{ "a_id": [ "gujctfr" ], "text": [ "So big animals have big hearts, and small animals small hearts. And so the big animals requires big Volume of blood pumpes out to cells needing fresh blood, thus in large slower pumps. And opposite with small animals, quick pumps with smaller Volume." ], "score": [ 7 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mr1n53
how can other animals instinctively tell they're related but we wouldn't know unless someone told us?
So there's been stories of people that didn't know they had been interacting with long lost siblings or cousins, what ever the case and they didn't know they were related until someone told them. But I've seen puppies separated and then they get reunited and automatically recognize that they're blood and things like that. So why do animals have that 6th since type thing that we seem to lack?
Biology
explainlikeimfive
{ "a_id": [ "guji9nc", "gujleuy" ], "text": [ "Pheromones. Animals produce chemicals called pheromones, which slowly turn to vapours in the air. Other animals that breathe those vapours in will detect them with their pheromone-detecting cells in a way that works basically the same as smell. Animals recognise the unique pheromones of those they're closely related to which subtly influences their behaviour. Humans have pheromones too btw, and it's thought that we also use this same mechanism to avoid wanting to fuck our siblings, and certain kinds of human pheromones can make us perceive people as more attractive.", "So this isn't always true... Some animals it's by smell, but there are tons of animals that fall for mimicry. Sometimes the shape has to be correct, other times they'll take in a robot that looks like it was put together by a five year old. For entertainment: URL_0" ], "score": [ 7, 3 ], "text_urls": [ [], [ "https://www.youtube.com/channel/UCDRZWhedLhwllnac-RBxvyw" ] ] }
[ "url" ]
[ "url" ]
mr1yzi
Why does water get bubbly if you let it sit for a while?
Chemistry
explainlikeimfive
{ "a_id": [ "gujme1o", "gujk6xl", "gujjvws" ], "text": [ "Gas (air in this case) can dissolve into liquids while the liquid is under pressure (as in the pressure in the water lines). It stays dissolved in the liquid, until the pressure is reduced/removed. Temperature also plays a part, albeit a lesser one than pressure. 5 is too young for middle school, but this explains it fairly simply: URL_0 Edit:. Also, that's how beverages are carbonated. The gas dissolves into the liquid under pressure. It stays dissolved until the pressure is released.", "I assume you're talking about when it comes out if a sink faucet. To save water, most faucets have a aerating nozzles. So it creates the appearance of more volume of water by either using a venturi nozzle or a fine screen mesh to mix air into the stream. Some fancy sinks have a pot filler faucet which doesn't have it so it fills up a pot faster. And many municipal water systems add chlorine gas, or ozone gas as part of the water purification process. And finally cold water can hold more dissolved gases than warm water, so it might be that as it sits it warms up from ground temperature to air temperature and releases some of the dissolved gases.", "You might have to describe this a bit more. Is this a glass of cold water left on the table for example?" ], "score": [ 12, 6, 3 ], "text_urls": [ [ "https://www.middleschoolchemistry.com/lessonplans/chapter5/lesson8" ], [], [] ] }
[ "url" ]
[ "url" ]
mr2b90
()Let’s say medicine advances to the point we can extend the lifespan of an ocptopus, will that make it possible for the octopus to continue evolving and learning more like we do with age?
Biology
explainlikeimfive
{ "a_id": [ "gujo2ac" ], "text": [ "Not necessarily. The science is still young, but evolution is not generally thought to be effected by the experience of the parents except for that the parents produce offspring. Given that longer living octopi would probably reproduce more then they'd just create more long lived octopi. What are the benefits of longer life? Well, they might get bigger and able to survive longer. But they might get slower and become easier prey. They might over populate and create a food shortage which may actually kill off the long lived." ], "score": [ 3 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mr334z
How does Sjogren's (an autoimmune disease) cause damage?
Sjogren's is an autoimmune disease. The body attacks the saliva and tear glands, resulting in reduced secretions. How does the damage happen?
Biology
explainlikeimfive
{ "a_id": [ "gujvqup" ], "text": [ "The immune system is really very violent. All it is capable of doing is killing things, and it won't hesitate to kill other cells of the body if doing so will fight a perceived threat. In fact, its basic response to viral infections is just to kill every host cell that's been infected, which is the body's equivalent of treating a plague by nuking the city its in. The immune system causes damage to the body when it finds something that it incorrectly identifies as being hostile. Unfortunately, it's not currently known exactly what causes the immune cells to do that in Sjogren's disease. It seems to be thought so far that it happens when something about the glands prompts an inflammation response it shouldn't normally have, so a mutated protein somewhere in that extremely complicated chain of activity that breaks the message in some way, recruiting immune cells to the glands when they're not necessary or keeping them around long after an infection is over." ], "score": [ 18 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
mr35lv
– What is happening when my eye seemingly "burps"?
Sometimes when I yawn or when I blink harder to refresh my eyes while doing computer work, one of the lenses of my glasses will fog up for about a second before clearing once again, leaving me wondering if my eye "burped." I googled and found stuff about painful pressure buildup following eye surgery, but as far as I know, my eyes are healthy and pain-free (if not just fatigued from computer work), and I've never had eye surgery. Is this just another way that the body gets rid of gas/air? Where does that gas/air originate?
Biology
explainlikeimfive
{ "a_id": [ "gujwgpl", "gujworm" ], "text": [ "Could be the hole in the eye that connects to your nasal passage. Tears going down this hole when you cry is what causes your nose to run when you are crying, and if you plug your nose (or have allergies) and try to blow out of your nose with your mouth shut you can have air go from your nasal passageway up and out of the hole. It sounds like you have a pocket of air where your sinuses are and when you yawn or blink hard you must release the air up and out of the hole in your eye. Kind of like cracking your knuckles but the air has somewhere to escape. I could be wrong but there should be no other hole around your eye for air to be released from", "Your eyes do exchange air with the atmosphere. Unlike most of your body, your eyes get their oxygen directly from the atmosphere, not red blood cells. I don't know exactly what could be causing this fog, though. Just anecdotal advice: eyes can seem totally fine when in fact there is something wrong with your retina/cornea/etc that has not made itself apparent yet. Or, the change has been so slow and subtle over such a long period of time that you don't realize there has been a change, like sometimes people don't realize their vision is going until they say someone says \"no that's totally visible to me\" or \"what do you mean you can't tell that's blue?\". I would call your eye doctor and explain what's going on. Maybe there's a totally normal reason but I would at least touch base with a medical professional." ], "score": [ 4, 3 ], "text_urls": [ [], [] ] }
[ "url" ]
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mr3v77
How does lighting know where to strike?
We all know that lightning will often strike metal or something tall, but why exactly is this? It seems logical that it would just strike randomly. How exactly does it "know" where something metal or tall is?
Physics
explainlikeimfive
{ "a_id": [ "gujxmiy", "gujww1l" ], "text": [ "Electric charge spreads out in all directions. The easier it is to move in one direction, the more charge moves that way. This is the \"path of least resistance\". The process is pretty random, some places the air is a little moister than others. However, when this random spread of charge reaches a low resistance ground, like a tall metal lightning rod, it can flow much more quickly than through the air because metal has much less resistance. This \"solves\" the path of least resistance to the ground problem, and as the electric charge flows it warms the air. Then it ionizes the air, greatly reducing the resistance. Huge amounts of current can flow through the ionized air, after the path has been solved. This huge current flow through ionized air is called lightning. When you see it there is a often a random jaggedness to it, because of the randomness of the path finding process. Of course, the huge current superheats the air, causing the sound of thunder.", "when clouds rub against each other, they create a bunch of electrons. electrons hate each other deeply, and push each other, trying to get from place where they are in abundance to a place where they aren't any. but they can't normally travel through the air, it stops them when their force of pushing isn't enough to go through. but electrons move easily through metals (and even trees are better than just the air), so when the resistance happens to be lower then their hateful forces, they rush there just like a water rushes through the hole when you pull the plug. the light comes from them rubbing against the air, releasing some energy" ], "score": [ 7, 5 ], "text_urls": [ [], [] ] }
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mr4b3b
When the body goes into ketosis, it burns fat for energy instead of sugar. So if an individual has extra stored fat, and they are in ketosis, why do they still need to eat (assuming supplements are used for nutritional needs)? Can’t they just use the extra fat for fuel?
Biology
explainlikeimfive
{ "a_id": [ "guk2bwh", "guk045a" ], "text": [ "Angus Barbieri lived on coffee, tea and vitamins for over a year (1965-66) in an effort to lose weight. He lost 276 pounds. He was supervised by doctors throughout the process. So what you're asking about is possible, but the real crux of what I think you're trying to get at is this: Hunger is much more complicated than your body telling your brain \"we need to refuel\".", "Well if someone who wasn't in keto just stopped eating and only started taking supplements for nutritional needs, what would happen? Because fasting for 12+ hours gets you in keto so..." ], "score": [ 29, 3 ], "text_urls": [ [], [] ] }
[ "url" ]
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mr4kin
Why does a car engine make the vroom noise, what is actually happening inside to make that happen?
Technology
explainlikeimfive
{ "a_id": [ "guk19ml", "guk1aqg", "guk1vsf" ], "text": [ "Car engines contain cylinders, cylinders use explosions to bounce up and down, turning things which then eventually turn the wheels. The vroom vroom noise is the sound of the explosions and resulting movement in the engine.", "Little tiny explosions. An engine works by taking in gasoline (or other fuels), mixing it with enough air to burn, compressing the mixture, then igniting it. The explosion pushes the piston down which in turn spins the crankshaft. The spent fuel then leaves the engine through the exhaust, along with the sound.", "For your usual gasoline engine, there are a bunch of explosions every second, all timed one after another so that it gives a mostly uniform power to the car’s drivetrain. The sound is the combination of the explosion inside the engine and the exhaust gasses from those explosions rushing through and out of the exhaust pipes." ], "score": [ 10, 7, 3 ], "text_urls": [ [], [], [] ] }
[ "url" ]
[ "url" ]
mr4wxr
What's the difference between voluntary manslaughter and murder?
Other
explainlikeimfive
{ "a_id": [ "guk3vxp" ], "text": [ "It depends on local statutes actually and can differ from place to place. Usually though manslaughter is considered accidental, it is you killed someone without malice or forethought, so not planned. While murder is done with definite intent. The line between them can blur though from place to place." ], "score": [ 3 ], "text_urls": [ [] ] }
[ "url" ]
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mr5qom
How does a smartwatch get heart rate using "green light" underneath the watch.
Is it also accurate? How does result compare to an actual blood pressure machine?
Technology
explainlikeimfive
{ "a_id": [ "guka3k0", "gukbyv0" ], "text": [ "That green light illuminates the skin, measuring changes in blood volume in the capillary vessels. They don’t really measure blood pressure, they measure pulse, and some level of VO2 (volume of oxygen moved through your system when exercising). The pulse I’ve always found to be accurate, and the VO2 max is also relatively close. Other metrics I’m not sure on yet. But the green light isn’t much different than the finger clip pulse-ox light that is routinely used in medical care", "Your blood absorbs the green light, so it monitors how much light reflects back and can detect each pulse of blood as dips in the amount of green light reflecting back." ], "score": [ 17, 10 ], "text_urls": [ [], [] ] }
[ "url" ]
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mr5s62
What is the endgame for the rocket boosters that can land again on Earth?
I’ve seen the videos and it’s Absolutely incredible. Where does this tech take us, what is the endgame, and what kind of advancements can be made to it to progress?
Technology
explainlikeimfive
{ "a_id": [ "guk9tcc", "guk9y8i", "guk9tpk", "gukfkm8" ], "text": [ "It makes space launches less expensive, which in the long run makes space more accessible and enables other activities because the economic barrier to reach space is reduced.", "The endgame for reusable boosters is speed and cost. If you reuse a booster, you don't have to: * spend time crafting a new one, or * spend money crafting a new one. That's basically it. It means you can fly missions more rapidly, and use materials on other things.", "Reusable rocket boosters can reduce the cost of launching payloads into space pretty drastically, since the boosters aren't exactly cheap to product. The challenge has been recovering them in good enough condition to reuse, which SpaceX seems pretty confident after working on it for a while ([and quite a few failures]( URL_0 )) One benefit of less expensive launches has already started deployments: low orbit satellite internet (Starlink)", "Let's say you run an airline. One airplane costs $200 million, and carries 200 passengers. If you ditch the airplane in the ocean and build a new one at the end of each flight, you have to charge a ticket price of $1 million per passenger to pay to replace the airplane. Of course that's a terribly inefficient, downright silly way to run an airline, and no real airline actually does this. Instead, you build your airplane so that it can be re-used; it might make 10,000 flights over multiple decades. You still have to charge $1 million per seat over the lifetime of the plane, but that $1 million can be divided among the 10,000 different passengers who sit in that seat on each of the plane's 10,000 flights. This means you only have to add $100 to the price of each ticket to be on schedule to save up enough money to replace the plane at the end of its life. Making space rockets re-usable will eventually reduce the cost of getting to space by *a lot*, since you can spread out the cost of the vehicle over many trips." ], "score": [ 12, 9, 3, 3 ], "text_urls": [ [], [], [ "https://youtu.be/bvim4rsNHkQ" ], [] ] }
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mr64nw
How do betting sites manage to control all the different live bets?
How do they keep control of all the ever changing live bets of all sports?
Other
explainlikeimfive
{ "a_id": [ "gukldel" ], "text": [ "They don't control the bets (mostly), they control the odds. They don't \\*have\\* to take a bet, they can cut it off anytime they want, but that's rare. They're constantly monitoring how much money is being bet on each side of a particular outcome and adjusting the odds so that they (on average) come out ahead. That's why the odds constantly change up until the betting cutoff." ], "score": [ 4 ], "text_urls": [ [] ] }
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mr6btl
If I'm driving at 60MPH and a car coming from the opposite direction at 60MPH and I get into a head on collision, Is that equivalent to me running into a wall at 120MPH?
Physics
explainlikeimfive
{ "a_id": [ "gukdlr5", "gukh03p" ], "text": [ "No. If both cars and their carried weight is equal, both cars will experience a change from 60mph to 0mph, which is the equivalent of running into a wall that changes your speed from 60mph to 0mph (assuming an infinitely strong wall that doesn't yield to your car).", "Mythbusters actually tested this, comparing the impact of a car going 60 hitting a wall, and two identical cars going 60 hitting head-on. The g-forces involved were the same in both cases. So, assuming equal mass and construction, it's like hitting a wall at 60mph." ], "score": [ 17, 7 ], "text_urls": [ [], [] ] }
[ "url" ]
[ "url" ]
mr6wsh
Why does a crystal radios radios antenna have to be so much longer than a normal radio
Technology
explainlikeimfive
{ "a_id": [ "gukhvyc" ], "text": [ "The antenna acts as the power source of the radio and needs to be long to harvest as much energy as possible from the very low energy radio wave. Powered radios simply amplify this weak radio wave." ], "score": [ 5 ], "text_urls": [ [] ] }
[ "url" ]
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mr706p
How does our body "sense" when we are near our destination when not paying attention to surroundings? (ex. Consistantly waking up when the bus is close to school.)
Biology
explainlikeimfive
{ "a_id": [ "guki4xl", "gukxe5h", "gukvxe6", "gukv1nu", "gul2cj7", "gukx3li", "gukyqko", "gukxmnb" ], "text": [ "The human body is exceptional at keeping time, even if the human mind struggles with it sometimes. ~~25~~ [24-ish]( URL_0 ) hours is about the internal clock's interval, and especially if fed a pattern, can adjust. This is accomplished with a mixture of brain waves and hormones. I began waking up an hour early every day for a project. After the first day of the surprise alarm, I began waking up consistently 15 minutes prior to the alarm once I'd gained familiarity with the new project and was actively thinking on it. Halfway through, once the routine was normalized and the remainder was all planned out and known, the novelty wore off. With less excitement, I began sleeping in until the alarm went off, and the usual dread of waking returned.", "Your subconscious gets programmed over time to process stimuli that you might not even be consciously aware of - there might be a particularly sharp turn, or the road surface changes very slightly but the tires make a slight different noise on the road, or the pattern of the light between the buildings shifts or there's a landmark like a water tower and your brain starts counting the minutes down from that water tower. Your brain is very good at pattern recognition and being able to recognize something even with minimal sensory input.", "In the case of a school bus, you might be getting cues from the people on the bus. Things like the sound of people reaching for their bags and changes in the level of concentration etc as you approach school might subconsciously send a message to your brain that you're close to arriving. This won't be so effective on a normal bus because everyone has their own different destination so the cues are spread out over every bus stop, and far fewer people are getting off on each one.", "For movement, there are also the Place cells and the Grid cells in your brain - helping you keep track, spacially, of your movement.", "Alternative answer here. You don’t. This is something called confirmation bias. You only pay attention to info that confirms your bias. You probably wake up before you get there plenty of times, you just don’t pay attention to them. Then you wake up when your nearly there and think “wow what a coincidence”. It’s the same as that old “when you think about someone and they suddenly call you”. How many times do you think about someone and they don’t call you?", "As some others have noted, your body relies quite heavily on routines. So if your bus ride is typically X length of time, your body will be used to waking up after a certain time/pattern. But when it comes to sleep, I'm not an expert, but it seems the brain is still quite active and somewhat responsive and if you hear people shuffling or other buses or people discussing arriving, that could also be processed while sleeping.", "When I sit down, I'm fine. If it's in a movie theater, still fine. If it gets dark when I'm anywhere, I'm fine. But when it gets dark in a movie theater, I have to go to the toilet with an urgency. Bodies are weird yo.", "Your uncounsious brain still operates when you are asleep, in case you go somewhere on a regular basis it is easier for your brain to wake you up at the right time!" ], "score": [ 1163, 121, 37, 27, 23, 18, 7, 4 ], "text_urls": [ [ "https://www.reddit.com/r/askscience/comments/2l8g5k/why_are_our_circadian_rhythms_longer_than_24_hours/" ], [], [], [], [], [], [], [] ] }
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mr72uy
Why do people iodize salt?
Was in a cafe today and saw this salt canister that said iodised salt. Why do they do that to the salt? What does it add?
Biology
explainlikeimfive
{ "a_id": [ "gukipsv", "gukiutv", "gukjmvz", "gukiq4s", "gukilcs", "gukswgr", "guks9gk" ], "text": [ "Iodine, in tiny amounts is necessary for the human body. It was found in the early 20th century that people were not getting enough in our diets. Salt is an easy delivery mechanism because it doesn't spoil and generally speaking it's a predictable delivery method for the amount necessary.", "It’s fortifying. Fortifying foods is when it’s hard to get it in our every day meals so we add it in. Iodine is one of those we don’t normally get so they add a super small amount into salt.", "To prevent a medical disorders involving your thyroid. People that eat a lot of shellfish get plenty of iodine in their diets so rarely develop issues such as goiters, iodine from other sources is much lower in concentration or completely non-existent so it is hard for people who do not or who cannot eat shellfish to get enough to stay healthy. As such one method of insuring that the population gets enough iodine is to fortify something virtually everyone will consume with it. And thus salt is commonly fortified with it.", "They add iodine to the salt. Your thyroid uses iodine to create hormones that regulate your healthy function. Iodine deficiency can lead to a number of problems including goiters.", "People need iodine to live healthy. Some places don't have enough iodine in the soil for the people there to not get sick. Government added iodine to salt because everyone eats salt. Iodine is tasteless, so it doesn't change anything about the salt. Today its likely less necessary than it was in the past.", "In Europe, starting in the 1950s, iodine was added to mined salt (as opposed to salt from saltwater which already contains it in sufficient quantity). Not only for health reasons but, for fear of nuclear conflict during the cold war, to saturate the thyroid gland with iodine-127, a non radioactive isotope of iodine. Nuclear fallout can cause the accumulation of iodine-131 (which is radioactive, hence is mutagenic/carcinogenic) in the thyroid, unless said gland is already saturated with another isotope. Iodine is the largest and heaviest of all elements present in the human body.", "People used to get diseases from lack of iodine if they didn't eat shellfish, the best dietary source; this problem was particularly visible in poor inland populations. The solution was to fortify a common food with a small amount of iodine. In the US it's salt; in other countries it's bread or milk. Almost all salt sold in the US is iodized, with the exception of fancy upscale salt (sea salt, pink salt, etc.) and Kosher salt (coarse salt that is produced for the purpose of drawing blood out of meat, though it has many more uses in cooking.)" ], "score": [ 61, 23, 22, 11, 8, 6, 4 ], "text_urls": [ [], [], [], [], [], [], [] ] }
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mr8468
It's common knowledge not to remove an object that's impaling you without a doctor around. So how do doctor's do it "safely?"
Other
explainlikeimfive
{ "a_id": [ "gukp6w6", "gukp9dr", "gukpjc0", "gukpb9c" ], "text": [ "With an operating room full of equipment to stop the bleeding as soon as they pull out the object. Things like clamps, sutures, and medicine.", "Typically a doctor has the tools to seal the wound up, stem the bleeding. The reason you don't do it yourself is you might bleed out and be too weak to see someone to help you. If a doctor is there, they'll know what you need if it is that bad.", "Dr.’s (should) know what type of/ the severity of the wound so they would also know how to safely remove it without causing more damage. A lot of people who remove the object end up hurting themselves further as they take it out. Once the object is out, they’re also immediately ready to treat it with clean tools/ supplies, whereas it’s unlikely that wherever your got hurt has the necessary supplies. If you take the object out and are unprepared to treat it, then you’re just more likely to bleed out.", "By stabilizing the impaled object and being able to control the bleeding internally. After that, they can safely remove the object during surgery." ], "score": [ 18, 10, 4, 3 ], "text_urls": [ [], [], [], [] ] }
[ "url" ]
[ "url" ]
mr86xe
What are the health differences between an elevated heart rate from exercise, or from stress/fear?
Biology
explainlikeimfive
{ "a_id": [ "gum25j4", "gul1v1x" ], "text": [ "elevated HR is not the only thing caused by stress/fear. * stress hormones can damage the lining of your arteries * stress can cause fatty acids and glucose beeing dumped in the bloodstream, causing deposits that decrease blood flow. **Long term stress is the real killer.** Your sunday morning run only lasts a hour and your body will recover from it and even grow stronger. Your stressfull job can last for years and your body doesnt get the time to recover from it.", "Heart rate is controlled by a variety of factors, including temperature, exercise, stress etc. When in exercise, the heart pumps blood to deliver oxygen, improving your cardiovascular system. After your stop your exercise, your heart rate slows. When in stress, a few different things happen. First off, the elevated heart rate stays for longer. Secondly, the body is flooded with \"stress hormones\", such as cortisol. These along with heart rate, also increases your blood pressure. So your heart has to pump faster with more pressure, for longer-term. This is bad for the heart/blood vessels in the long term, leading to heart attacks, haemorrhage, stroke etc." ], "score": [ 8, 3 ], "text_urls": [ [], [] ] }
[ "url" ]
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mr8agw
Are photons emitted from a source at infinite angles?
As I understand it, a photon is a massless particle constantly emitted in a linear direction, from any light source. When considering that the light source hits all objects, potentially billions of LY away, does this mean photons are emitted at infinite angles?
Physics
explainlikeimfive
{ "a_id": [ "gukrjus" ], "text": [ "Kinda...photons are somewhat particle like but also somewhat wavelike so they have some spatial extent. They're not a point, they have \"area\" in the sense you're talking about. But if you go far enough away then the photon flux (photons per area) will drop away to below 1 and then the light is so dim that you're only getting sporadic photons, not a continuous stream. On average, they're emitted at infinite angles but any particular photon does have a direction." ], "score": [ 5 ], "text_urls": [ [] ] }
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mr8c1l
When you close one eye, you see a blank image where that eye should be able to see. However, if you lose an eye, does your brain completely ignore that eye, or can you still see a blank image?
Biology
explainlikeimfive
{ "a_id": [ "guky1rx", "guku3pr", "gul90n6" ], "text": [ "when you cover one eye your brain almost instantly adjusts to that so you don't see a dark shade covering half your visual field, instead you just lose your depth perception and half your normal field of view. I don't see why losing the eye would be much different, except that given more time your brain would adjust better and things would probably look \"normal\" again instead of that weird feeling you have covering one eye where it feels like you're only seeing from one side.", "I think it would be a blank image because in both casas you stop getting info from the nerve Connection the Eye to the brain", "Not sure but I think you’re still seeing your eyelid in the case of closing your eye, like how the sun can still be uncomfortable while sunbathing. Whereas if the receptors arent there you really aren’t receiving any stimuli at all. I’ll have to ask my aunt next time I see her" ], "score": [ 8, 5, 3 ], "text_urls": [ [], [], [] ] }
[ "url" ]
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mr8ejb
Is sound volume not absolute or why is it so hard to make music/videos on one standard volume level?
Physics
explainlikeimfive
{ "a_id": [ "gukr16c" ], "text": [ "Yes sound can be measured in decibels and production companies know what they're doing. Over time, producers of various media realized that if they increase the gain on their media, that the audience will be more aware of it. It sacrifices audio quality for marketing. Check out: The Loudness War: URL_0 URL_1" ], "score": [ 4 ], "text_urls": [ [ "https://www.youtube.com/watch?v=3Gmex_4hreQ", "https://en.wikipedia.org/wiki/Loudness_war" ] ] }
[ "url" ]
[ "url" ]
mr8fkr
Why do video game developers choose to only release games only on some consoles/PC but not others? How much more work does it take to program a game to operate on a different console, say Switch vs Playstation for example?
Technology
explainlikeimfive
{ "a_id": [ "gukrchh", "gukqyx9", "gukus4i", "gukuycy", "gukr8bh" ], "text": [ "It takes a lot of work. Consoles tend to have less power than PCs and each of the major consoles uses a different operating system. PC and Xbox share a lot of internal code, but PCs have thousands of combinations of parts, compared to the consoles all using the same processors. For a small studio this is a lot of work. In general game companies have two options: make a game run okay on all platforms or really well on one. I’m a PC gamer, but I’m shocked at how well God of War and Horizon Zero Dawn run on the PS4. Knowing exactly what hardware your game will run on is a major help to optimization. And also, game companies sometime sign contractors to only release on a single console. Sony may pay a company a million to not sell their game on the Xbox. Or in the case of Bethesda: Microsoft owns them, so they’ll be making almost exclusively PC and Xbox games from now on. There you go, it takes a lot of people and time to make a good cross platform game, and there’s a lot of money involved in keeping games from getting ported.", "developing for consoles have a lot of limitations, require you pay licensing fees, console manufacturers require that they to verify your updates before you can push them out (thats why you cant mod skyrim and stuff like on pc), you have to worry about supporting different control schemes, you need separate servers for consoles and pc unless your game works well in crossplay, you will have more bugs come up when you support more systems, it's sometimes easier to integrate with something like the steam API rather than integrating separately with each platform, you need to hire experts for the different consoles you support, and there's probably a whole host of other reasons people will bring up", "A good comparison is trying to take a European Car and importing it to the U.S. I mean, cars are cars, right? Shouldn't be too hard. However, while European Cars and American cars are basically the same technology... There are a bazillion American rules and regulations that don't match European rules and regulations. There are obvious things like which side the driver sits on. There are less obvious things like bumper heights or fuel standards. Then there are really dumb things like European Cars having wider license plates than American license plates and thus the screw holes are in the wrong place. Each of these differences requires attention from the car importer and it takes a lot of time and money. Porting a game from one platform to another is similar to importing a foreign car. It seems easy since all game consoles basically run on the same basic technology nowadays, but it's the small things that take a lot of time to get just right.", "it's not just that - different platforms have different costs involved, and different expectations. some smaller companies can't justify the cost to get it certified for consoles, so they just don't bother.", "Different hardware, different APIs, often different capabilities--you can produce a game that has much better effects on a PS5 than you can a Switch because it's simply a far more powerful machine; the Switch sacrifices capability for portability. If you were to just do a straight port of a Switch game to the PS5 with no upgrades then PS5 owners would consider it to be rather shabby looking. So, in the most extreme examples you could be talking essentially rewriting the game from scratch, including all the visual assets--your only advantage is that you already know how the game is supposed to work, and you'd probably be able to re-use the audio assets because those capabilities don't change much between systems." ], "score": [ 30, 9, 7, 3, 3 ], "text_urls": [ [], [], [], [], [] ] }
[ "url" ]
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mr95ng
Why do some statistics count numbers in the millions “in thousands?”
Mathematics
explainlikeimfive
{ "a_id": [ "gukxmmw" ], "text": [ "I'm assuming you're actually talking about visualizations of data, like graphs. If one of the dimensions of your dataset is just a collection of very large numbers (e.g. all the population counts of South American countries) it's easier to just add a footnote \"*thousands\" so you don't have to write out all digits in the visualization." ], "score": [ 3 ], "text_urls": [ [] ] }
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mr97og
Why is it so uncomfortable to hear people making mistakes with sentence structure or grammar in a language that you are fluent in, sometimes to the point where you cannot concentrate on the content? What happens in the brain to make it so distressing?
Biology
explainlikeimfive
{ "a_id": [ "gukyclv", "gukykbu" ], "text": [ "Your brain doesn't just listen to the things that are being said - it also tries to predict the future. So it tries to guess what the next word will be or how the whole sentence will end. If it's constantly wrong though it's thinking more about why it's wrong and why the anticipated word didn't come and then it's trying to do two things at once: Listening and ordering the words into a structure that makes sense to your brain.", "A huge part of any language is pattern recognition. When you are truly fluent in a language, and especially if it's your native language, your brain knows how sentences are supposed to be formed. So, unconsciously, your brain is predicting what the next person is going to say, or is at least what they could say. Then, when what is said doesn't line up with that unconscious prediction, it causes a cognitive dissonance that can be very uncomfortable. It's like learning a song, and then hearing a sour note in the melody when someone else plays it, or hearing a crunch as you eat pudding. Your brain is very good at recognizing when a pattern has been broken somehow." ], "score": [ 8, 6 ], "text_urls": [ [], [] ] }
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mr9coz
what is the difference between electric and electronic?
Technology
explainlikeimfive
{ "a_id": [ "gukwkwr", "gukx4fq", "gukwuyw", "gukx1pt" ], "text": [ "electronic is when you transmit digital information/signals electric is when you use electricity to power your device.", "To be a little more specific, electronics implies the device uses transistors, which are components that allow for things like logic circuits and amplification.", "Simplistically: Electric is usually the term used for something mechanical driven by electricity, like a washing machine, while electronic is used for things that use electricity as power source to do calculations of some sort, like a computer. Instead of driving a motor, the electricity (in tiny amounts) is used to turn \"switches\" on and off in processors etc. In a washing machine, the program cycles are electronic, while the engine is electric (electro engine).", "Electronic generally implies that there is some kind of integrated circuit/microprocessor logic in the device which plays an important part in its functioning, whereas “electric” (as opposed to electronic) devices use primarily “simple” components like motors, heating elements, lights, and non-semiconductor based circuitry. But there is definitely a lot of fuzzy overlap with these terms." ], "score": [ 17, 6, 5, 3 ], "text_urls": [ [], [], [], [] ] }
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mr9otp
So what would happen if a hospital got hit by a power outage?
Technology
explainlikeimfive
{ "a_id": [ "gukxys1", "guky0l0", "gul47za" ], "text": [ "Hospitals generally always have backup generators that kick in immediately in the event of an outage, as long as they have fuel for them, power outages are not an issue.", "Hospitals are built with a backup system in place, to protect in case of a power outage. This is usually a generator that will kick in to protect the patients as necessary, until power can be restored.", "Depends on the location but in Australia typically they have UPS (uninterrupted power supply) battery backup for the main computers, surgical lighting, 30% of the hospital lighting and comms systems. The computer systems are designed for 15-30mins backup and the lighting is 90mins. This system provides power the instant mains power is lost untill the generator is up and running. The hospital will typically have a diesel generator with diesel storage for 24hrs at full capacity. The systems that have generator backup will vary depending on the hospital but typically it's any system that is critical for patient safety such as the medical gases, isolation rooms, life support etc. The generator is required to start within 5mins - newer systems can usually ramp up in 30secs. A 'disaster' hospital, designed to be able to withstand a natural disaster, will have full backup of the hospital with duty/standby (2N) redundancy on the generators." ], "score": [ 12, 6, 3 ], "text_urls": [ [], [], [] ] }
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mr9skf
What makes the storage of data so costly?
Both analog and cloud thoughts are welcome ~ all thoughts really (that aren't humanely offensive) ! Music producer. Constantly re/de-connecting external HDD's for the sake of 'online files' in one project. Is there also a proportion between data-size and what vessel encompasses that storage?
Technology
explainlikeimfive
{ "a_id": [ "gukzdkb", "gukzix2" ], "text": [ "First I'd like to say that storage of data in the cloud is dirt cheap, so I don't really understand the motivation of your question. A rule of thumb is $0.02 per month per GB. How is that expensive? Now for the cost drivers: * Availability: If you want a guarantee that your data will always be available to you, the provider has to duplicate it, so that if anything bad happens to the \"original\" storage they can point you to the \"copy\" instead; Similarily backup & recovery also require additional copies to be kept all the time, so for every GB of data you actually have to pay for several more GB as well * Security: If you want your data to be safe from theft and manipulation, the provider has to employ security measures, like different types of encryption, an elaborate idendity and access management, network separation etc.; this is not specifically for your data, but you will have to pay for a share of it * Processing: The actual expensive part of cloud hosting is not data storage, but data processing. So the more you work with that stored data, the more expensive it gets. Copy stuff? Expensive. Encrypt/decrypt stuff? Expensive. Upload new data? Expensive. Browse your files? Expensive. * Hardware and basic operations: Your data resides on some kind of hardware, even in the huge cloud datacenters of Amazon, Microsoft, IBM, or Google. That hardware costs money, both in original purchase and in upkeep, as in replacing faulty disks, providing it with electricity, cooling it, monitoring its health, occasionally scanning for viruses etc. * Profit: The hosters want to make money of the services they are offering to you, so most likely you not only pay the storage, but also quite a few \"useful services\" around it. This is like when you buy a washing machine, they also offer you a warranty extension, water softener, sock sacks, special detergents etc.", "storage of digital data has become cheaper basically by the day over the past few decades and honestly is far from costly right now, at least if you're not talking \"longterm-storage\" aka 50+ years storage, that requires a bit more thought and relies on systems that arent directly related to the consumer products. I have no idea, what you mean by \"constantly re-connecting external HDDs for the sake of online files\", normally you should just connect it once and then it stays connected. you could also consider getting a NAS if you want to access that data from more than one computer (which I am interpreting is what you mean by 'online files') wenn you're talking about analog data then obviously there's a connection between data-size and the required size of the vessel, like your room needs to have a certain size to fit a specific number of books or vinyls into it. for digital storage, well there are limits to the storage capacity of modern hard drives, but since those hard drives are basically all the same size with varying amount of storage space (from basically nothing up to 10 or so TB per disk) and the fact that you can often compress digital data (zip files, for example) I'd say there's no direct connection there." ], "score": [ 9, 3 ], "text_urls": [ [], [] ] }
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mr9u0o
What is Ambra1 and how can we produce more of it? (There is new research which helps understand tumour growth)
I've just read an article which states that "Ambra1 regulates the abundance of D-type cyclins by mediating their degradation". It also says that "AMBRA1 helps to maintain genomic integrity during DNA replication, which counteracts developmental abnormalities and tumour growth." Here is the [link]( URL_0 ) to the source. Can someone please explain what Ambra 1 is and how we can make sure that our body produces enough Ambra1?
Biology
explainlikeimfive
{ "a_id": [ "gul0omp" ], "text": [ "Your cells have a \"cycle\", where the cell grows, replicates its DNA, and divides. The cycle needs to be tightly controlled, as if the cell keeps dividing in a random fashion it leads to cancer. Ambra1 is a protein that the cell uses to prevent this, and control the cell cycle. As for producing more of it, that's something you probably shouldn't do. Ambra1 acts to prevent cancer, yes, but it acts via controlling your cell cycle (it controls a class of proteins called cyclins, which you can think of as the pedals that control the cycle). It prevents them from being overactive and producing stress in the cell. Having more Ambra1 than needed would probably mean your cells cycle more slowly, meaning you wouldn't be able to heal and grow as needed. This is bad. Very bad. The body is a giant balancing act, and having too much of anything is not a good thing. EDIT: OP, I'm not sure what level of technical background you have, so I kept it as simple as I could. I can provide a slightly more detailed answer if you wish." ], "score": [ 3 ], "text_urls": [ [] ] }
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