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Why do elements decay with half-life and not with constant rate? | Building upon u/crossedstaves great explanation. Another way to think about it is this thought experiment: You have 1,000 people in a room, each with a dice. Every second they roll. They are eliminated when they roll a 6. Now. How long will it take to elements the first person? How long will it take till everyone is go... |
What is a Deja Vu? | Something you already know what is.. you already asked this question before, no? I remember. But, if you don't, Deja Vu describes the fascinating and strange experience where you feel that something is very familiar, but you also know that this feeling of familiarity should not be as strong as it is. For example, you m... |
Spicy food doesn't trigger the taste senses in our tongues but the nerves that detect pain. So, why do we like the pain that spicy food creates? | Why don't you like it? Evolution. Your body thinks the plant is posion and telling you to avoid it. That might not be entirely accurate, but plants will take advantage of it. The plant, evolution wise, is trying it's best to be poisonous, just like nutmeg, cinimon, basil, and all the other spices. And they're failing d... |
How does the expansion of the universe work? And how is it possible that more and more of the universe is becoming unobservable? | It doesn't expand into anything because there's nothing to expand into. The universe is everything, it just happens to be getting bigger. When the universe was younger it expanded so fast that light from some parts hasn't had time to reach us. Due to distance and ongoing expansion, light from some parts of the universe... |
How do we know so much about planets that are light-years away? | We don't really know much about them. If we can detect how much they are pulling their parent star around, we can estimate their mass; we can estimate the mass of the star, which together with the time an orbit takes, can determine how far from the star the planet orbits. If the planet passes between us and the star, w... |
Why do we sing in the shower ? | I would say that it's for two reasons. First of all, showers are basically boring routines and there's not much to do in there. . Singing is an easy way to occupy your mind beyond the mundane. Second, as others have said, an enclosed space provides some high quality acoustics. |
Why do we feel relief when we "crack" our knuckles/joints? | I'll give this a brief go. It isn't officially known what it is for definite which makes the cracking noise but it seems to be widely accepted that the cracking is the formation of a bubble between the bone joints as oppose to common thought being that a bubble is popped. As for feeling good it could be due to this bub... |
how does a fan cool down the air in a room | simple answer: it doesn't. that's your bodies reaction to the same thing as wind. if it's hot enough, it will feel like warm air is blowing on you. however if you have a ceilling fan on the winter setting, it pushes air upward and outward. this mixes the air in the room as heat rises. so the less than one degree differ... |
What is the difference between a religion and a cult? | Every religion starts as a cult. It doesn't have the social support of a large community of believers, so the remaining non-believers don't really have incentive to treat them favorably or better than mild neglect. When they convert enough believers, they become a like-minded force in the community enough to affect the... |
Difference between a 'disease', 'disorder', and 'syndrome' | I've learned it more as a conversation about illness vs disease. An illness, like a cold, has clear symptoms. The goal is to treat the symptoms to get rid of them. You are looking to take away symptoms. Same goes for depressions. Treat the symptoms so they go away. Disorders, like personality disorders, require adding ... |
What is "mental exhaustion"? | i think it's mostly the stress; in the unlikely event i go through a productive day at work with minimal stress , i find i'm still energized when i get home. It's really when i'm not taking good care of myself in the ways listed above that i feel drained. and stressed. |
Why do you get a runny nose when it's cold? | You don't. Your lungs are a very warm and moist environment. Air leaving your lungs is likewise warm and moist. When it hits cold air, the moisture condensates and ends up dripping out of your nose. Incidentally, this is why it's important to stay hydrated even in the winter. |
Why is fast food considered unhealthy? | Restaurant food tends to more unhealthy that what we would make it home. A lot more butter, oil, or grease is used in restaurants that we wouldn't use at home. There tend to be a lot of empty carbs as well - fried, bread, rolls. The portion sizes are larger than needed - it is very easy to inhale 3/4 of your daily calo... |
Why do you need an "escape velocity" to leave earth's gravity? Since gravity is a force, shouldn't it be countered by an "escape force" and not velocity? | sure, you need an escape force over a distance . so now it's escape force over distance, which is energy. Kinetic energy, to be exact. Which is directly related to velocity. Now, since objects can have different mass, you can say it takes xxkJ*kg, or more simply a velocity. |
if gravity is gets weaker the further away you are from a large mass, why can't rockets leave the earth by just flying at a low constant speed? | Escape velocity is the speed at which you can escape *without* any additional force. Your idea requires that you keep firing your engine . Real spacecraft also tend to want to enter orbit. Orbit doesn't have anything to do with escape velocity, because you don't escape. To you enter orbit, you need to be going very, ve... |
Why do we need to cook our meat before we eat it but wild animals are fine eating it raw? | We can eat raw meat just like animals. They're eating fresh kills, and we can do the same. It's the bacteria on decomposing meat that we would have a problem with. Cooking can also alter protein structures which help us get more calories out of our food, on top of killing bacteria . |
Theoretically why can't objects go faster than the speed of light? | F = ma doesn't work for a relativistic rocket. If the ship moves forever with constant proper acceleration , its acceleration relative to a stationary observer will asymptotically approach zero, and its speed will asymptotically approach c. It will never reach nor exceed c. |
Does the expansion of the universe mean there is a limited distance you could travel from Earth and still return? | Yes there is a maximum distance you can travel and still return because at one point you'd be far enough that the space between you and Earth would be expanding faster than the speed of light. |
Why do we feel centripetal acceleration when we're say, making a turn in a car, but don't feel any centripetal acceleration from the revolution of the Earth around the sun? | We do get some centripetal acceleration from the Earth's rotation but because it is constant, very small, and in the exact opposite direction to gravity we don't notice it. Because of centripetal acceleration you would weigh roughly 0.3 to 0.5% more standing at one of the poles than at the equator, where the Earth's ro... |
What happens to all the Helium we create as a byproduct if we start nuclear fusion on a very large scale? | We can store it if we want, but if you're worried about there being too much of it, don't. Helium is actually too light to stay in our atmosphere. It will move to the top of our atmosphere and escape into space.Helium which is released will float to the top of our atmosphere and be blown away by the solar wind. Natural... |
Why do we have fingernails/toenails? why not just have skin? | Our distant ancesters had claws. As we evolved and didn't have a need for claws anymore, they flattened and became nails instead. |
Why do we use binary number system in computers? | Because it's easy to set up a logic gate using transistors If we do. Binary at the physical level comes down to charges. All we have to do then is check if there is any charge and we have successfully translated from digital binary to physical change. By using binary transistors can be made much simpler and much smalle... |
Why are most Western Languages written using a common alphabet but more Eastern/African alphabets written using different sets of symbols? | Western languages typically use versions of Roman Alphabet because of the massive reach of the Roman Empire at a critical point in the development of western civilization when scholars throughout Europe had more time to do scholarly stuff . Latin was sort of the lingua franca back then. It had a strong foothold by the ... |
How can we see the Moon at night when it's between Earth and the Sun? | We can't. When they're exactly in line we call it an solar eclipse. If they are only roughly in line, it's simply daytime.It is not between the Earth and the sun. It is only between the Earth and the sun during an eclipse. There will be a total eclipse next summer over a small part of the US. There is only one line bet... |
How can the universe be both "infinite" and "expanding"? | I run a motel with an infinite number of rooms, numbered 1, 2, 3, etc. It's beach season, so all of my rooms are full, but i find out there's a convention of mathematicians coming to town this weekend, and an infinite number of mathematicians will need rooms. All my rooms are full, but i really want that sweet conferen... |
How do know how to pronounce writings on the ancient clay tablets like kushim tablet? | Plus it's a lot of hoping to be right. Olde English doesn't sound like you think it does because the accent you are hearing it in on stage and even in your head is wrong. It is easier to read and translate but speaking ..much harder |
Why haven't we gone to the moon since 1972? | What for? The moon doesn't hold any valuable mineral or fuel, colonizing would have no economic or scientific benefit, and getting men there is expensive. The only use we'd have for a moon base is off-planet launches , but that would require first a reason for frequent space launches beyond sending a satellite into Ear... |
Why does garbage always smell the same? | I had a very short career working with garbage collection but my experience is that cans have individual smells, but after putting a few of them into the truck you end up with the generic odor that we can't get enough of.Bacteria is what causes the smell is why. Garbage is like a food buffet for many bacteria. Just lik... |
Why do "bad" smells smell bad, and "good" smells smell good? | Some smells are universally hated because they are evolutionarily disfavored. The smell of poop or decaying bodies can indicate disease or bad things so our ancestors evolved an aversion to it. Other things are acquired tastes/smells, which depend heavily on how you're raised. If you smell a durian fruit without being ... |
What exactly is anti matter? | Antimatter is more of a physics concept than chemistry. It's also not just opposite charge - the particles also have opposite lepton numbers and baryon numbers. These numbers are a bit more abstract, but they're always conserved. A baryon has a baryon number of 1. A lepton has a lepton number of 1. So an antiproton has... |
Why some people are more accident prone than others | intelligence and reflexes. People lacking reflexes can't act fast enough to act safely. People lacking the needed level of intelligence can't see the pattern of events leading to injury, damage or death. |
How does gravity from the Sun, effect us here on earth, if there is nothing between the earth and the sun? | The ''net'' actually exist and it's spacetime. Here a nice video that actually help visualise gravity. The blue sheet in the video is spacetime. _URL_0_", 'Spacetime is a "thing" that is the medium that holds all "stuff". Gravity is the observed effect of stuff with Mass bending spacetime. Just because there is no "stu... |
Why does space in our universe only have 3 dimensions? | What you're asking is why spacetime has the signature that it does and unfortunately that's an unanswered problem in physics! These no reason that it couldn't be 4-1 or 3-2, it just happens to be 3-1 in our universe. |
What would happen to the kinetic energy if an mass of antimatter was shot into an equal mass of matter. | Let's take a simple example and assume that a particle collides with its equivalent anti-particle. For example, a positron collides with an electron. Energy and momentum must be preserved in the collision. If the two particles collided very slowly, so that kinetic energy and momentum were negligible, the result would b... |
What is dust and how does it get everywhere? | Dust is any finely grained substance, including pollen, pollution, sand, dirt, and more. Indoor household dust is made up primarily of shed skin cells from the humans who live there, and any animals kept as well. Dust gets everywhere because as it's very fine, it's light enough to be picked up by any breeze, even just ... |
What's the difference between dark matter and antimatter? | Antimatter is stuff. Antimatter clumps can bump into other antimatter clumps. It has friction. You can see it. It interacts in common-sense ways. Antimatter and normal matter annihilate when they come into contact with each other, but otherwise they're just two sides to the same coin, and can be described in almost exa... |
Why does string theory require that there be 10 dimensions? | This won't be a satisfying answer, but you're asking a question that doesn't lend itself to satisfying answers. String theory requires 10 dimensions because the theory is simpler with 10 than it is with 4. And for the record, not all string theories require 10 dimensions. Basically any theory from 10-26 dimensions can ... |
Why is it that hangovers get worse the older we get? | Because you can't afford to stay in bed for 12hrs+ afterwards due to work, kids or other mandatory activities. |
why the moon doesn't rotate around an axis perpendicular to the earth | The moon does spin. The moon's axis is roughly parallel to Earth's axis just as Earth's axis is roughly parallel to the Sun's axis. The moon rotates at just the right speed that the same part of the moon is always facing Earth. |
Why does Pi have infinite digits? | There is nothing special about irrational numbers like Pi. Indeed, whenever we come across some constant that we can define mathematically, chances are it is irrational. As well as Pi, there is the 'growth constant' e, Fibbonachi's 'Golden Ratio' phi, and the square roots of 2, 3, 5, and pretty much any non-square numb... |
if incest is so bad because of recessive genes, how come mentally challenged, (for instance downs) couples are allowed to breed? | Down syndrome is a really rare occurrence ever if two people with Down syndrome had a child it's extremely likely the child will have no problems.In general, everyone is "allowed" to breed. You won't be arrested for incestuous sex . It's just extremely socially taboo. |
Why haven't the large space rocks in the Asteroid Belt and Kuiper belt coalesced to form large planets due to their gravity? | The Asteroid belt cannot combine due to Jupiter. Jupiter's gravity tears apart anything that gets too big. The Kuiper belt is too spaced out. But it does have a number of dwarf planets like Pluto. |
Why are the 7 continents when Europe and Asia are basically the same land mass? | What we define as a continent and not a continent is really convoluted. If you have time, I'd take a look at [this video.] |
why do hangovers get worse through the day? | Your body needs to replenish essential stuff like electrolytes, fluids, and phospholipids. If you don't acquiesce, your body will strongly disagree, and for much longer. |
Why did Europeans developed themselves in a much stronger way than for instance Native Americans who remained at a relatively small level of development when Europeans found them? | Native north Americans staid in the stone age, for a few reasons. However the one most people don't realize is the main factor is animal domestication. North and South America have two animals that can be domesticated. Llama in the south and reindeer in the north. Both animals tame very quickly and domesticate easily. ... |
Why does room temperature not feel very cold to our bodies? | Air is pretty bad at taking heat away from you. It's a similar reason to why water feels colder than air even if they are at the same temperature. Water is great at sucking in a large amount of heat. |
The difference between morals and ethics. | Ethics are those actions that are moral or immoral as defined by society. Morals are those actions considered good or bad that are imposed by either the 'self', or by something considered a higher power . They're frequently but not always the same. For example, an adult brother and sister having 100% safe, 100% consens... |
When an ice cube melts in a glass of water, the water level stays the same. Therefore my question is how come water levels are rising because of the ice caps melting ? | The ice cap is not floating. Their weight bears on continental land masses, so the analogy doesn't apply. As they melt, the sea level will rise accordingly. Furthermore, the melt water is fresh, while the sea is salt - roughly a 2.5% difference in density, so the overall salinity of the seawater will be reduced, slight... |
Why is it colder at higher altitudes even though hot air rises? | Let's say you have two containers that are sealed. One has twice as many atoms or molecules in it than the other. Both containers are the exact same size. The more molecules or atoms you have the more hot they will be. There will be more random collisions between particles. The closer you are to the surface of the eart... |
What is the difference between serotonin and dopamine? | Some good answers here. Something that's being overlooked are the other neurotransmitters in the families. Serotonin is made into normelatonin, which is made into melatonin. Insufficient serotonin can be linked to poor sleep, as it leads to insufficient melotonin. Dopamine is made into norephinephrine , which, in turn,... |
What is the benefit to a company to enact a policy that prohibits promotion of employees from within? | It would be a good way to prevent the [Peter principle] from coming in to effect, I think. I expect it could also prevent a cascade of promotions to hire a new employee to fill a position rather then have to promote a guy to replace the guy that was promoted. And I suppose that getting someone new from outside the comp... |
What would happen if we detonated an atomic bomb in the eye of a hurricane? | It wouldn't make things better; you would just end up with a hurricane full of radioactive dust and debris. There are two things to understand here. First, hurricanes are friggin' huge. Way bigger than nukes. The biggest nuclear bomb ever actually exploded was about 50 megatons, or 2 x 10^16 joules. The energy a hurric... |
When planets are visible from earth, why do they appear as stars to us on the surface of earth? | The term you're talking about is angular diameter. You can see the disc of the moon, because it's a combination of two things: close enough and large enough. If the moon were much farther away, it would appear as a dot. Of course planets we can see with the naked eye, are much larger than the moon. However they are so ... |
How can we talk about the universe being flat? Is it not expanding in all directions? | Take a piece of paper and draw a line between 3 points so you have a triangle. If you measure the angles inside this and sum them up you get 180 degrees. Now grab a globe of the world or any other sphere. Start from one of the poles, draw a line to the equator, now carry that line along the equator for a quarter of the... |
Do prime numbers exist in different base number systems, like binary, hexadecimal, or base 60 that the mesopotamians used? And, are they useful for anything? | Prime numbers are the same no matter what counting system you use. There aren't any numbers that are prime in base 10 that aren't prime in binary or hexadecimal or vice-versa. Probably the most immediate economic use for prime numbers is in encryption, where products of very large prime numbers are used because it is v... |
How do sanctions against a country work? | The most common form is a bunch of countries banding together and agreeing not to do business with another country. That doesn't mean just not buying from them, but also not selling to them. Very few countries now are self-sufficient, so a country might end up with a surplus of something they manufacture but don't real... |
The 11th Amendment to the US Constitution | Remember to cite Reddit when you turn in this homework. This is the text: > The Judicial power of the United States shall not be construed to extend to any suit in law or equity, commenced or prosecuted against one of the United States by Citizens of another State, or by Citizens or Subjects of any Foreign State. It ef... |
What happens in our body the moment we fall asleep? Also why dont we ever remember falling asleep? | You can train yourself to remember when you fall asleep. I remember some of the time. I just start thinking about things and forgetting where I am. It's weird. And hard to explain. |
Why is the moon so much closer near the horizon than at its apex? | It's not. It only [looks larger], in fact if we measure it it's actually 1.5% smaller. There's no definite explanation yet, either it's due to apparent distance or relative size |
If two humans have perfectly identical DNA, just how similar would they be, think, and behave? | Identical twins have identical DNA. There's difference in the expression of DNA, but the base pairs are the same. Some DNA is influenced by environmental factors in how it expresses itself. It's why identical twins have different fingerprints. |
How and why does gravity effect time | You need to know that time is a part of space-time. Space and time are inseparable. Like gravity compress space it compress time. Imagine, you want to go from A to B in a space time non affected by gravity. It's separated by 10 meters and you need 1min to travel the 10 meters. Now imagine you need also to go from A to ... |
why don't we use a slingshot, like an aircraft carriers, to launch rockets and shuttles to space. Wouldn't that reduce the onboard fuel needs? | A slingshot to get objects both through the atmosphere and anywhere approaching orbital speeds would necessarily subject the vehicle and any occupying people/probes/things to tremendous acceleration. It'd be like trying to cross the street by having a friend hit you with a car to save on walking. You'd need a way to sp... |
Why can't we just like take a giant telescope and look at the planets that NASA discovered? Similar to how our Satellites can zoom in on earth. | Satellites take pictures of things from about 100 miles away. A planet that's 40 light years away is 235,100,000,000,000 miles away. So, you'd need a camera that is about one trillion times more powerful than what's on a satellite. |
If calories are the measure of how much energy there is in food - how can things be 0 calorie? | Yes, you'd starve. 0-calorie food is made of stuff you can't digest. Since you can't digest it, it comes out in basically the same form it came in, which often causes intestinal difficulties. Due to some wiggle room in labeling laws, you can have up to 5 calories/serving and still label food as 0-calorie.Yes. It has ze... |
why does the existence of wormholes automatically make time travel possible? | It's a hypothetical technique: 1. Using time dilation , make the far end of the wormhole move through time more slowly than the near end. So for example the near end reaches the year 2200 but the far end is still back at the year 2198.2. Jump in the near end and pop out the far end. Now you're at a place that's back in... |
How can photons actually be massless? | A photon has energy and momentum, but exactly zero mass. There is no fundamental rule which requires particles to have mass; some do and some don't. The photon doesn't. |
Why are protons attracted to each other in a nucleus if they are positively charged? | Sure, the protons hate being this close. But the electromagnetic force isn't the only force acting on these particles. The Strong nuclear force wants to hold these nuclei together and on the very short ranges within an atomic nucleus it is stronger than the electromagnetic force. This is also why nuclei need a balance ... |
If hot air rises and cold air sinks, why is it colder at the tops of mountains? | Low pressure from high altitude = colder air. PV=nRT. Inverse relationship between P and T. This has more of an effect than 'hot air rises', since any warm air that makes it to the mountaintop is quickly cooled down |
Why does a planet that is very close to its star (or a moon to its planet) often becomes tidally locked ? | > The only way I could make sense of it is if one side of the planet/moon had more mass than the other, This actually really close. Consider the earth and the moon. One side of the moon doesn't have significantly more mass, but it is a closer to the Earth, so it feels the gravity more strongly. This deforms the moon in... |
What would happen if a nuclear device was detonated in outer space? How far would the blast travel? | This has actually been done before.it was called the Starfish Prime experiment done in the 1960's", 'Blast is a compression wave. There are no blast waves in space, as there is no medium to compress. The debris would go a long way, with no air resistance. The super-bright flash would also travel great distances.When I ... |
If galaxies are moving away from us faster than the speed of light, how can we ever get to them? | We can't. Any object distant enough that the intervening space between us and it is expanding faster than light can cross said space, is effectively removed from our observable universe. Barring some method of traveling faster than light, it will become forever inaccessible to us. |
How do we know the light shift from other galaxies is due to expansion and not something like light losing energy as it travels over large distances and through material? | If light was slowing down as it moved through space the red shift would be greater the farther away the galaxy was. So any 2 galaxies the same distance from our galaxy would have the same red shift. I don't know if this has been verified but that would be a way to check. |
Why fusion reactions stops when final product is Iron ? | _URL_0_ In short fusing elements releases energy until they get up to iron and afterwards it starts consuming energy on the aggregate. This basically means that stars cannot be fueled by iron fusion, so unless the star goes supernova and basically explodes heavier elements aren't made. |
How do you play Dungeons and Dragons | It's not that complicated and you can even play digitally. Check out _URL_0_. Everything is done by rolling dice and cooperative story telling between the players, and the game/dungeon master. The basic rules are available for download, and they describe more than enough to get started. |
What IS Autism?? | Now there's a tough one. There are a few problems here: 1) There is no such thing as 'autism'. What we refer to as autism is actually a long list of different disorders, all with their own symptoms. 2) Even within that list, one specific disorder has a wide spread of severity, ranging from Rain Man-like behavior to bar... |
Reptiles are air breathing animals. However, when they're in an egg, they have no source of air like mammals do in the womb. How do they survive without air while developing? | The egg shells are porous, which allows oxygen to diffuse into the shell and carbon dioxide to diffuse out of shell. This is also why when you use farm fresh eggs, you need to wash them with **warm** water, so the contents of the egg don't contract and 'pull' bacteria into the egg via the pores in the shell. |
If the air scatters all the colours away so we can only see the blue light, why doesnt looking through *more* air at sunset look more blue? | So what you are referring to is Rayleigh Scattering. Basically it accounts for the way specific wavelengths get reflected in the atmosphere so we can see them. Longer wavelengths do not get reflected as frequently as your shorter wavelengths . However the sun does not produce much violet light, so we see more blue colo... |
Why is water wet? | Well, for starters, there are two kinds of intermolecular forces at play here: Adhesive force and cohesive force. Adhesive force is the one between two molecules of the different kind and cohesive force is the one between two molecules of the same kind. In the case of water, the adhesive force overpowers the cohesive f... |
The difference between bees, hornets, wasps, and yellow jackets. | hornets and yellow jackets are different types of wasps. Most wasps are predators and eat other insects, although many wasps will eat sugar in the fall months before they die. Female wasps can sting repeatedly without dying because their stingers are not barbed. Wasp sting venom is alkaline, so it can be neutralized wi... |
Why did the Nazi's use a swastika for their flag? | The Swastika is based on the Nordic 'solar cross,' which is two 'sun' runes crossed over each other. Hitler was a nut for that sort of mystic symbolism, and the original Teutons were thought to be from parts of Scandinavia.The Nazis wanted to return Germany to a pre-Christian/pagan Aryan race ideal, so they chose a sym... |
Sleep studies. How do they work? | You have to fall asleep on your own. You go in at early evening, they spend about an hour attaching electrodes to your head and body. These all feed back to a control room where they monitor you the whole time. You usually only need a good two hours of sleep. Then they remove all the electrodes and send you home. Your ... |
Why do we twitch in our sleep? | Are you talking about a [hypnic jerk] ? No one really knows why it happens, but it's pretty common. Some of the theories involve some sort of misfiring as the muscles are supposed to wind down for the night , an evolutionary tic, a weird transition into deeper sleep stages, and perhaps something related to sleep spindl... |
Why does hot water out of the tap look cloudy. | All water has some level of junk in it. Small amounts of dirt and sediment and other minerals. Over time that stuff builds up on the walls of the pipes in your house. Hot water actually starts to dissolve some of that junk from the walls of pipes and that's what you see in the water. Cold water isn't anywhere near as g... |
How does fusion produce more energy than fission? | In a nuclear reactor, you take big, heavy atoms and split them apart. This releases a relatively lot of energy — about 200 MeV. You don't have to know what an MeV it , but just keep the relative unit in mind. In nuclear fusion, you are taking two light atoms and smashing them together into one. This creates a sort of u... |
Why do we fidget? | Numerous research display that fidgeting virtually has some blessings. However what compels humans to twitch and tap, seemingly without control over their motion, in situations when they're known as directly to be nevertheless? Turns out, there is at the least one biological rationalization. The identical mind regions ... |
Conservation of mass, food to energy and nuclear fission | Sugar is C*_6_*H*_12_*O*_6_*, but to form it you need not only those atoms but also *energy to power the reaction*, which gets locked up in the sugar molecule as binding energy. Our digestive & respiratory systems break such food molecules apart into smaller, simpler molecules with less binding energy and use the diffe... |
why is the speed of light the universal speed limit, and not just the fastest thing we've been able to observe? | It is confirmed by everything we've ever observed. We've tested and proven it countless times, and the math makes it pretty clear that nothing can go faster. However, that just means that everything we know now confirms it. Like with all things, its entirely possible that there is something we do not know that could ch... |
Why does a certain species of any animal all look identical, but any specific race of humans have enough differences to create diversity | A great Dane and a teacup poodle look pretty different to me, but they're both the same species.This is due to something called [speciation], when evolution creates a new and distinct species. This is generally determined when an animal of the new species cannot mate with an animal of the species they evolved from.In t... |
How did we establish the universal rule of 'righty tighty lefty loosey'? | It's not completely universal that threads are right handed. There are particular reasons why some are made left handed. Just a couple of examples:- Bicycle pedals are attached to the crank with one of each so that they don't come undone with the pedalling action which turns one pedal clockwise and the other anticlockw... |
Antibiotic-resistant viruses and bacteria supposedly might harm the human race, but why can't we just develop stronger antibiotics/treatment? | 1) There isn't a lot of money to be made in a drug that someone takes for two weeks. There is a much greater incentive to develop drugs that are used in disease state management rather than short duration cures. 2) We haven't found a viable new target for antibiotic therapy in quite some time. Antimicrobials kill livin... |
What's the difference between AWD and 4WD? | There are technical differences between the 2, but the core is this. AWD is intended for use 100% of the time. Most AWD vehicles do not include the ability to turn it on or off. 4wd vehicles are normally RWD unless 4WD is engaged. It is not considered a good idea to engage 4wd on dry pavement or at normal driving speed... |
If you already have a cold, are you immune from catching another one on top of it? | Yes. But it's not as likely because typically you'd have caught the predominant strain in your region, which means you can't re-catch it. |
When something surpasses the speed of sound why does it create a sonic boom, and would it be possible for an object to avoid creating a sonic boom? | The sonic boom is an intense compression wave, caused when the wake from the rear of the plane reinforces the wake from the nose of the plane. It's the same thing as the crack of a rifle bullet going past your head at over the speed of sound. To avoid making a boom, you;d need to not make a wake, or to spoil the wake. ... |
Why does the the human mind ignore the second “the”? | You're brain operates by following patterns. When you're reading a word, your brain looks at the letters all at once, not sequentially, so it can identify the word very easily even if certain letters are switched. It works the same way for sentences. Your brain takes the entire sentence and analyzes as much as possible... |
Why is it that low-frequency radiation like Wi-Fi, and high-frequency radiation like X-Rays, can both pass through walls, but medium-frequency (visible light) is blocked? | Could you clarify that simple statement about the rock vs bullet thing, it's kinda confusing. I think I know what you mean, but it kinda sounds like you might mean it has something to do with the properties of a rock, not it's velocity. |
Why is it that so many people in the southern United States are so patriotic and all about America when the south wanted to secede from the union? | Well, the people today who are so patriotic *may* have grandparents' grandparents' grandparents who wanted to secede . Do you know what your grandparents' grandparents' grandparents stood for? And do you still care about it? |
why do we get hiccups and how do they work??? | We can get them when we suddenly breathe at a time that interrupts our natural breathing rhythm and the muscle of our diaphragm contracts unevenly. The muscle that pulls our lungs down to fill them can then spasm, tightening quickly, forcing us to inhale sharply, causing the classic *hiccup* sound as air rushes past ou... |
Why do moons orbit around planets instead of the sun? | Firstly, what we define as a moon is an object that orbits a planet. There are a few moons in the Solar System that are larger than dwarf planets. Secondly, the strength of a gravitational pull weakens exponentially with distance. The Earth's gravity is much stronger than the Sun's while close to the Earth . If the Moo... |
Why does looking at the sun or other bright light make one, or assist one with sneezing | Only I would actually have my dream of having a mutant ability come true only to turn out to that it's the ability to sneeze when I see light. |
Theoretically, why can't countries shut off their power grids in case of an impending nuclear strike to avoid them getting fried by the EMP? | To protect against an EMP, you would need to completely shield all of your sensitive electronics from electromagnetic radiation. Simply turning off the grid doesn't do this. Even unplugging everything wouldn't keep them from getting fried if they were close enough to the blast. |
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