title list | over_18 list | post_content stringlengths 0 9.37k ⌀ | C1 list | C2 list | C3 list |
|---|---|---|---|---|---|
[
"If time slows down proportionally, the closer to the speed of light you travel, does that mean that time has no existence to a light wave in a perfect vacuum?"
] | [
false
] | I've been getting WAAAAAAY into the cool parts of science lately. Rewatched every through the wormhole episode, currently halfway through "Physics of the Impossible" by Michio Kaku, watched tons of episodes of Nova, and one question I haven't seen answered(yet), is whether time exists at all for a light wave travelling... | [
"Do you understand mathematical limits?",
"If you take the function, then yes the limit approaches \"zero\" or \"no time\".",
", nothing moving at c can have a valid reference frame, because the equations are undefined at c.",
"So the answer is \"light waves in a vacuum cannot have a reference frame\", and al... | [
"I can't answer your question, but I feel that you're missing a bit of interesting information: The faster an object moves, the more space in front of and to the back of the object seems shortened. E.g. when you fly from Earth to Andromeda fast enough that it only takes a second, which is universe-technically possi... | [
"A light wave doesn't experience time. Interestingly it doesn't experience distance either - the point and time of emission is the same as the point and time of a photons absorption from the photons perspective I think.",
"The limit you've taken is correct, but there is no such thing as a \"photon's perspective\"... |
[
"Does modern medicine actually make the human species less fit by allowing traits that would normally die out to be passed on?"
] | [
false
] | null | [
"Fitness is the ability to survive and reproduce. Modern medicine contributes to the fitness of those with access to it.",
"Does modern medicine actually make the human species less fit by allowing traits that would normally die out to be passed on?",
"What do you mean by normally?"
] | [
"Just a few things to thinks about:",
"The majority of people alive today do not have access to quality medicine, and most don't even have access to basic needs like clean water, food and shelter. So for them even what we might consider basic things can kill - like malnutrition.",
"Selection can only really act... | [
"I believe a good example of a normal trait that would normally be harmful would be lactose intolerance. The inability to get sufficient calcium when young leads to all sorts of medical concern later in life, most of which would reduce your fitness and would make you a poorer choice for a mate."
] |
[
"Why won't honey freeze solid?"
] | [
false
] | null | [
"Honey contains too much dissolved solid, sugar, to freeze. There is only 18% water in honey, which is too low to freeze. At extreme temperatures, honey's viscosity will become extremely thick and sluggish until it reaches a point of glass transition and becomes a non crystalline amorohous solid. It won't be frozen... | [
"It does, just at a lower temperatures than you'll find in most home freezers. ",
"https://www.youtube.com/watch?v=BybpWzed600",
"The very high fraction of sugars acts as antifreeze. The technical term is \"freezing point depression.\" It freezes at around -50 deg C.",
"The sugars also prevent ice crystals f... | [
"Is it possible to add something to it to make it freeze, such as a little water?"
] |
[
"Is it possible to have \"neutron chemistry\", as in the classic book Dragon's Egg?"
] | [
false
] | null | [
"Chemistry is based largely on the attraction between protons and electrons, which determine interactions between different atoms. It is the ambivalence, in part, of proton-electron attraction and proton-proton/electron-electron repulsion that is at the source of many of the complex chemical interactions which I wo... | [
"I don't believe so; smaller clusters of neutrons are not stable. It's only the massive gravitational field of a neutron star that holds it all together. ",
"We do know that ordinary chemistry-as-we-know-it is ",
"very different",
" in the huge magnetic fields that you can have near neutron stars though."
] | [
"In the book, it's made clear that the neutron compounds are only stable in the gravitational field of the neutron star."
] |
[
"What is the purpose of wired-glass windows for doors to patient's rooms in hospitals?"
] | [
false
] | null | [
"I believe it is to keep people from easily breaking through the glass. It is a double pane with metal in-between which makes it tough to simply shatter unlock the door. I've seen them in schools as well."
] | [
"Psychiatric patients often enter the hospital as medical patients. Sometimes medical patients become aggressive. Making glass more difficult to shatter/break is a protective measure for patients/staff/visitors."
] | [
"Wire glass prevents the glass plane from completely coming apart therefore minimizing the exchange of gases through the broken pane during a fire and preventing a shattered spread of glass hitting people.",
"What is the purpose of wired-glass windows for doors to patient's rooms in hospitals?",
"Preventing the... |
[
"When a child has one tall parent and one smaller parent, the child's height does not necessarily lie in between the two. How do the parents' genes affect this trait or any trait in particular that shows similarity to this trend?"
] | [
false
] | null | [
"Every gene is inherited in the simple mendelian probabilistic way you probably learned about in high school where you get a copy from mom and a copy from dad (with a few exceptions but theyre not relevant here). ",
"However, height is what’s called a quantitative trait. Rather than height being controlled by a s... | [
"We don’t really understand the genetics of height. It seems that about 80% of what decides your height is genetics and the other 20% is environmental factors such as nutrition.",
"The problem with understanding things such as height on the genetic level is that it is so complicated. Many people when they learn g... | [
"Even eye color is multi-site, which is why our class was taught attached or unattached earlobes, hitch-hiker's thumb, and male pattern baldness."
] |
[
"Is the uncertainity principle constrained by the speed of light?"
] | [
false
] | If the momentum of a particle can be determined only on probabilistic grounds, is there a chance that its momentum will cause it to exceed the speed of light upon movement? Or would the particle's wave-like nature dominate in this situation and somehow the particle ends up not vilolating the laws of nature? (Just like ... | [
"You're probably defining momentum wrong. momentum, p=(1-(v/c)",
" )",
" mv . You're probably used to seeing p=mv which is just the low velocity limit. You can see as v->c. p->infinity."
] | [
"No, it's not possible that a particle could \"cheat\" its way past the speed of light.",
"Let's set aside momentum and position — both continuous operators — in favor of something simpler: spin. There are three spin operators, one for each orthogonal spatial axis you might care to define. These three operators d... | [
"This may be silliness, but I'm just trying to understand it properly. I've never understood why this doesn't work concerning the uncertianty principle, maybe you can enlighten me... ",
"Ok, so let's say you set up some kind of lattice of detectors such that you can say with certainty where a particle is NOT (i... |
[
"Could you \"cancel\" out a sound wave in a similar fashion radio wave interference is caused, making it inauble relative to position with an \"opposite sound\"?"
] | [
false
] | Worded slightly different: Can you have two out of phase sound waves projected at a person from different locations to create interference to where the person would hear no noise at all? EDIT: Oops, I meant "inaudible" in the title. | [
"Of course!",
" This is how noise-cancelling headphones work."
] | [
"Yes you can. Its used in noise cancelling headphones as someone has already mentioned and its also used on some planes to reduce the noise of the aircraft jet for the passengers. Interestingly, although it is possible to make it almost completely silent for a passenger on board, humans freak out if they cannot hea... | [
"Yes, within limits. If you don't calculate the \"anti sound\" properly, you will increase the sound. Active noise cancelling headphones work by having a microphone close to your ear, amplifying the sound and inverting it before sending it to your ears. Doing it from across a room is very difficult. The process is ... |
[
"Is sound, bound by gravity? Is screaming upwards any different than sceaming downwards, speed or volume-wise?"
] | [
false
] | null | [
"Everyone is thinking air density and air pressure, which is wrong. The speed of sound in air is mostly based on the air temperature, and to some extent humidity.",
"To put it simply, hot air is already moving faster, so it bumps into each other faster. Cold air is the opposite. So the speed of sound is faster... | [
"There is a recent observation that ",
"sound waves carry small gravitational mass",
". A theoretical derivation can be found ",
"here",
", which shows that even in Newtonian limit, the mass is non-zero. This is pretty weird though, and I have no idea what the implication is."
] | [
"I'm still having trouble understanding why gravity wouldn't have a direct effect on how sound waves propagate. It seems like if gravity is pulling on the molecules of whatever the sound is moving through, then the wave should propagate differently depending on whether it's moving towards, away from, or perpendicul... |
[
"Why does skin bubble up with liquid after a bad burn or injury?"
] | [
false
] | How is the liquid produced? What is it and what is its purpose? | [
"Its basically interstitial fluid. After injury, the cells break down adding their intracellular fluid to this interstitial fluid part. Plus the body reponds by vasodilation which means more blood goes to that part. This blood plasma then extravasates to extracellular regions due to chemical signals and osmosis. Re... | [
"My biologist friend told me not burst blisters because they contained 'magic healing white blood cells'."
] | [
"You don't want to burst blisters because skin (epidermis) acts as a natural barrier to the environment and when your blisters pop it exposes your dermis and allows for infections, delayed wound healing, and scarring. This isn't so consequential with blisters < 2cm but with bullae or ",
"blisters > 2cm",
" it ... |
[
"How can anything ever reach any event horizon ?"
] | [
false
] | So as far as I understand, the clock of a particle that approaches the event horizon, will run ever-slower compared to an external viewer, eventually stopping at the horizon itself (only stopping for the external viewer of course, the particle itself does not feel time slowing). So, since black holes do NOT have an inf... | [
"According to an external observer, yes, that's completely correct. According to the poor bloke falling into the black hole, there's nothing special about the event horizon, just a continuation of the same old impending sense of utter doom."
] | [
"And if he turns around to observe the universe, would he see it proceed at what seems like a superfast rate?"
] | [
"Actually, There was a theoretical paper done suggesting that nothing ever does cross the event horizon; and this is a possible solution to one of the problems of black Holes and entropy. If I wasn't on my phone instead of a more reasonable computer, I'd see if I could find it. Hopefully this will jog someones me... |
[
"Bluetooth power: Is more power consumed from the phone's battery when volume is adjusted?"
] | [
false
] | null | [
"Hi CoolMarch1 thank you for submitting to ",
"/r/Askscience",
".",
" Please add flair to your post. ",
"Your post will be removed permanently if flair is not added within one hour. You can flair this post by replying to this message with your flair choice. It must be an exact match to one of the foll... | [
"Computing"
] | [
"Computing"
] |
[
"How am I able to collect so much lint from my dryer without my clothes visibly losing fabric?"
] | [
false
] | null | [
"Have you weighed how much lint you are collecting? I would assume the fraction of weight lost is quite small. How many times you can tumble dry your clothes before they are worn out? "
] | [
"Think of it like cotton candy. One of those big cotton candies you get at the fair are equivalent to something like 1 packet of sugar, and the rest is just air."
] | [
"You wont see it between individual washes but if you look at it after many washes you might be able to see the difference. "
] |
[
"Is the Euler Identity at all a consequence of the way complex numbers are represented?"
] | [
false
] | I have actually had a class in college in complex analysis and know at least that complex numbers are shown on the complex plane. I think that the geometrical interpretation of operations upon complex numbers comes from this. So what I mean is, if it is possible to "think" about complex numbers in some way that does no... | [
"In a sense, the Euler identity is true because we decided a long time ago that it should be true, but we had some very good reasons to do so. There are at least a couple explanations for why the Euler identity \"is true\" (i.e., why we chose to define complex exponentiation in this way), that make the advantages o... | [
"It doesn't have anything to do with the representation of complex numbers. Notice that I didn't refer to the complex plane anywhere in there, or make any sort of geometric argument.",
"I want to stress that there is a very deep connection between this operation and exponentiation. There was a choice made to iden... | [
"A common representation of complex numbers is ",
"2x2 matrixes in a special basis",
"."
] |
[
"Is there a study showing a causal link between tooth brushing frequency and oral health?"
] | [
false
] | Every dentist out there tells us how important it is to brush our teeth twice a day, floss every day, and so on to maintain our oral health. Yet a cursory look through the scientific literature doesn't reveal a single study demonstrating a causal link (or even a correlation) between tooth brushing frequency and oral he... | [
"Do you have sources for these statements? I'd love to see the underlying science."
] | [
"Do you have sources for these statements? I'd love to see the underlying science."
] | [
"The following one shows that as toothbrushing increases, general oral health decreases:",
"The relationship of frequency of toothbrushing, oral hygiene, gingival health, and caries-experience in school children - James Berenie 1973",
"http://www.ncbi.nlm.nih.gov/pubmed/4146723",
"Oral health and oral motor f... |
[
"How does anti-venom counteract a poisonous snake bite?"
] | [
false
] | null | [
"Why are horses, sheep, or goats able to create antibodies for venom while people aren't? Or are we able to, but a snake bite typically delivers enough venom that it overwhelms the immune system?",
"Human antibodies are more expensive to harvest for anti-venom because it requires injecting a human with venom."
] | [
"You are absolutely correct. A person would certainly mount an anti-horse IgG response if injected with horse antibodies. It is possible to treat a person with antibodies derived from another species, but the person would eventually mount a neutralizing response against the foreign antibodies, and they would no l... | [
"Venom is injected into an animal. The animal creates antibodies to fight the venom. The antibodies are harvested and bottled into antivenom."
] |
[
"What exactly are pheromones? Can we actually \"smell\" them?"
] | [
false
] | In tandem to the question: is there a scientific formula for what makes someone attractive and does a more attractive person have stronger pheromones that make them more appealing to the opposite sex? Just thought of this - Is there really a "Sex Panther"-type cologne out there that harnesses pheromones and literally m... | [
"There's not a lot of great evidence supporting the existence of human pheromones. It looks like we have some similar homologous but vestigial structures, but I don't think any solid studies have demonstrated that pheromones actually do anything in humans.",
"In rodents and various other mammals, the nasal cavi... | [
"Pheromones are chemicals secreted by the human body that are used to signal a response in other humans (and possibly some animals). They can be meant to signal any range of emotions from attraction to fear. ",
"As for \"smelling\" them - well, we do intake pheromones through out noses, but they are not detected ... | [
"I had read somewhere that human pheromones were inert, and such structures were vestigial at this point. Is this correct?"
] |
[
"Does quantum randomness mean determinism isn't true?"
] | [
false
] | So I've heard that, at the subatomic scale there is true randomness, things happen that have no cause. What I dont understand is how this translates to big things? Does that mean determinism isn't true? | [
"If such a test was indeed performed, yea, it would imply that determinism wasn't true.",
"This isn't correct. Only local hidden variable theories are disproved by the Bell inequalities; global hidden variable theories which may or may not retain full determinism (such as ",
"de Broglie-Bohm theory",
", whic... | [
"Whether randomness exists or not hasn't been confirmed yet, a conclusive, loophole free Bell test is yet to be performed. If such a test was indeed performed, yea, it would imply that determinism wasn't true.",
"'things happen that have no cause' is rather strong. All it implies is that the outcomes of certain o... | [
"So I've heard that, at the subatomic scale there is true randomness, things happen that have no cause.",
"We don't know that for certain. We only know that we cannot predict many of those things that happen, and can only constrain them using probabilities.",
"The question of whether nature has a truly random ... |
[
"Do photons have a gravitational field?"
] | [
false
] | Since photons have energy, and energy is related to mass via E=mc do photons have a gravitational field? | [
"Rather than thinking about mass, the better way to think about it is that photons have momentum/energy, and momentum/energy is a source of gravity in full relativity. So the answer is yes. In fact, radiation was the dominant source of gravity (in terms of effects on the universe's expansion) in the early universe.... | [
"they should in principle have one, we just don't know how to do the calculation to figure out what it is. But not because it has mass, it doesn't, but because it has momentum, and momentum creates curvature fields too."
] | [
"What about this?"
] |
[
"Shisha vs. Cigarettes and the nicotine"
] | [
false
] | Hi, this question has been on my mind for quite some time. The nicotine levels in Shisha is much higher than that of a cigarette. I know shisha CAN be addictive, but it seems like the addiction rate is much lower than cigarettes. Is there something else added in the cigarette that makes it more addictive and not just t... | [
"No firm conclusions can be drawn from what you describe. There are far too many variables surrounding addiction; brain biochemistry, genetics, psychology (arguably = brain biochemistry), smoke constituents, the quality/purity of the tobacco burnt, the conditions of combustion, etc. etc. ",
"The only thing that I... | [
"Forgive my ignorance, but is there anyway to smoke Shisha without some sort of device (traditionally a Hookah)? I have always heard about the debate between whether cigarettes or Hookah was worse for you but it usually focused around the difference in mechanics (or lack there of), not the difference in the tobacc... | [
"This has been posted multiple times, but I'll post it again anyway:",
"One of the key things about addiction is that a small reward that's repeated constantly is more addictive than a big reward that's done rarely. This is why cigarettes are at least as addictive as heroin, even though the immediate reward of a ... |
[
"Why does sunburn itch? And why do some people tan, while others burn/peel?"
] | [
false
] | [deleted] | [
"First, the current idea of why we tan: UV radiation/light allows us to get bioactive vitamin D (3) from the sunlight; but having lots of melanin spread out in your skin will lower your VitD3 production. ( I assume you know about the 'creation' of white people) But in contrast to this, UV destroys folic acid, and h... | [
"Thanks for the answer!",
"Following your first point, is it more difficult for those with darker complexions to get their dosage of VitD from the sun?"
] | [
"It is my understanding that it would, but you should double check"
] |
[
"Can water exist in a liquid state at below freezing temperatures?"
] | [
false
] | I was thinking, and this question randomly came to mind. To my understanding, Water expands when frozen. So, my question is, if you placed liquid water in an unbreakable container (or extreme pressure), would it be possible to keep water liquid below 0 degrees, since it wouldn't have the room needed to turn into solid?... | [
"Yes, although it's a bit more accurate to say that water can exist as a liquid at a temperature below its freezing point ",
" since the melting/freezing point itself is a function of the pressure. Water is one of the few substances that has the property that its freezing point can actually drop as you increase t... | [
"Additionally, ice crystals require a nucleation site to form on. In perfect distilled water in a perfectly clean container, water will remain in liquid form despite being below 0°C",
"You'll see videos of this phenomenon happening by searching superfreeze water or something along those lines."
] | [
"It's called \"supercooled water\", and is the physics behind freezing rain."
] |
[
"Is there an analytical way to solve hard single variable equations?"
] | [
false
] | for example: x = (sinx)(tanx) I know you can find a good approximate solution for large x, but is there any analytical way to find all solutions or do you need to solve it numerically? | [
"As far as I know the equation is transcendental and has no closed form solution in terms of elementary functions. Some special cases you can find roots for equations like this, but this doesn't seem like one. You can show solutions exist with calculus, and approximate them with Newton-Ralphson iteration."
] | [
"OK, but it's easy to extend ",
"/u/expandamatic",
"'s question into something that isn't obviously \"No\", like \"Can you always prove that you've found all possible numerical solutions to a transcendental equation if a finite number of solutions exist [and prove that an infinite number or zero solutions exist... | [
"You can prove that sin(x) has infinitely many roots though. Usually you're going to want check for changes in slope and concavity, and for a general function that's going to be really hard since you'll be looking at roots of the first and second derivative which isn't usually going to be much nicer to do."
] |
[
"How intensely do fish feel/sense/remember pain? Worms? (Basically, should I feel bad about fishing)"
] | [
false
] | I am going on vacation to a lake in the Pocono Mountains on Saturday, and I was wondering, should I feel bad about going fishing with a worm as bait? The worm isn't a big problem for me, as I remember the thread with the lizard and lighter mentioned that only vertebrates have complex nerve endings (or something like th... | [
"There's a fairly decent overview of the research here: ",
"Can fish suffer?: perspectives on sentience, pain, fear and stress",
"This review of the anatomy, physiology and behaviour of fish suggests that they are\nmore likely to be sentient than not. Therefore, in any fish farming enterprise, the welfare of\nthe ... | [
"\"Fish have recently been shown to have sensory neurons that are sensitive to damaging stimuli and are physiologically identical to human nociceptors. [...] In light of recent research, some countries, like Germany, have banned specific types of fishing, and the British RSPCA now formally prosecutes individuals wh... | [
"I guess what it also comes down to is the number of nerve endings (nociceptors, if I'm right?) in the fish's lip that determines just how much pain they feel, correct? Do we know just how much pain they feel from that zone, it being (from my experience) less muscular and more bony?"
] |
[
"Do men carry specific genes for female traits, such as breast size? Do women carry specific genes for male traits, such as penis size?"
] | [
false
] | It's my understanding that a person's genes are half from the mother and half from the father. But what about opposite gender-specific attributes, do we all carry those too? If I had a daughter, would I have any influence on her attributes, or would it only be mother -> daughter? Also, I was specifically wondering if t... | [
"A father has just as much effect on his daughter's female attributes as her mother. The genetic material passed down from mother to daughter is chromosomes 1-22 plus an X chromosome. The genetic material passed down by the father is again chromosomes 1-22 plus an X chromosome, thus for every chromosome given by th... | [
"There is one case that I know of: epigenetic imprinting. DNA in our cells is laced with hundreds of types of proteins that work together to express only the right genes at the right times. All cells have most of their DNA shut off (a liver cell will never have eye-related genes turned on, but the DNA for those gen... | [
"To add.",
"In the female case, the only argument that can be made for either parent having more input (apart from mitochondrial DNA) is that females tend to have a mosaic expression of their X chromosome. This means that in one cell only the mothers chromosome will be expressed, whereas in another cell only the ... |
[
"Why do salmon and eels need to migrate up rivers to reproduce? Why can't they spawn where they live?"
] | [
false
] | null | [
"This framing is actually a little bit backwards: in general, these species aren't migrating long distances to reproduce, they are migrating long distances to live at adults. What I mean is that you have a kind of fish that live in a certain habitat and spawn in that habitat, but then sometimes members of that gro... | [
"Salmon eggs and newly-hatched fry are physiologically unable to survive in saltwater. They undergo a process called ",
"Smoltification",
" when they leave their hatching pool/lake/etc and head towards estuaries, whereby their bodies begin to adapt to living in saltwater prior to reaching the ocean.",
"When s... | [
"The reason they travel back upstream to inland fresh water is because the salmon that didn't do that, did not survive!",
"Easier to find food but harder to find a mate and successfully reproduce in the ocean.",
"Natural selection for the win."
] |
[
"What determines how long immunity would last?"
] | [
false
] | Why does immunity against some viruses last for life and some just a few years (and needs a boost in case of vaccination)? What makes the difference? | [
"Immunity is when our bodies have the ability to respond quickly to a foreign agent because it has been “trained” by prior exposure (whether that’s naturally or artificially). This immunity is basically made possible by the existence of immune cells like memory B and memory T cells. These cells have receptors on th... | [
"You should probably distinguish between long-term memory B-cells hidden deep into the lymphoid tissues, they can be reactivated in a few days and protect from a severe disease, and the blood circulating B-cells and soluble antibodies, protecting from the infection itself. Also not only the amount of antibodies mat... | [
"Antibody cocktails can lead to cross reactivity with unintended targets and subsequent toxicity in many cases. That’s why the “mono”clonal antibodies are of special interest. If we can identify 1 epitope (target) for an antibody and design and antibody that can bind it with high affinity, you’ll be able to minimiz... |
[
"Why are solar panels flat and not concave?"
] | [
false
] | Wouldn't using concave mirrors to gather light and produce a single focal point produce much more power, heat, and energy from the sun than the flat panels? | [
"I think you are confusing ",
"solar panels",
" with ",
"solar furnaces",
".",
"A solar furnace typically ",
" have parabolic mirrors like you described which reflect sunlight to some concentrated point with the hopes of using the heat energy (by say, boiling water) to generate energy.",
"Solar panels... | [
"This is correct. To add to this, there are specific types of PV cells that require lenses to concentrate the light onto a small PV chip to obtain high efficiencies. Some actually use the excess heat to obtain ",
" energy. Basically a combination of solar furnaces and solar panels."
] | [
"REDACTED"
] |
[
"Why does the length of twilight differ according to latitude?"
] | [
false
] | I have observed how day changes to night much more quickly at the equator than at home around 50°N. Do the seasons also change twilight's length here? | [
"Nearer the equator the sun sets/rises closer to perpendicular to the horizon, so twilight is quicker due to more of a straight shot. At higher elevations the sun sets/rises at an angle to the horizon, so twilight lasts longer. ",
"Think of a right triangle, near the equator the sun travels more along the height ... | [
"So twilight is when the sun is near or just below the horizon. The length of this period has to do with what direction the sun is moving across the sky. There are two directions we use in solar tracking: up-down (solar altitude/zenith angle) and sideways or “around” (azimuth). So if you think of twilight being som... | [
"There is a band of roughly constant width of \"twilight\" around the Earth, just behind the terminator (the place where direct sunlight ceases to fall onto the surface). At the equator, the surface of the Earth is spinning the quickest, so something on the surface there traverses this twilight region the quickest ... |
[
"Does electricity need a high voltage or a high current to continue through a gap in a wire?"
] | [
false
] | Say with a 0.5 mm gap would it be possible for me to get electricity consistently jumping across without dealing with a deadly current? | [
"You need high voltage. Air is a very poor conductor, but by providing the electrons with a high voltage, they have sufficient energy to ionize the air between the two ends of the wire and create a conductive channel.",
"At standard temperature and pressure, you'd need 3 kV per mm of distance, so in your case, yo... | [
"As a wonderful example - lightning. Bridges a huge gap from cloud to ground with millions of volts but not always fatal. "
] | [
"When you're TIG welding, you have to \"strike\" the arc initially, either by touching the workpiece or by using a high frequency start. Once the electricity is flowing, it ionizes the air between the tungsten and the workpiece, which greatly reduces the resistance of the air so the arc can be maintained."
] |
[
"Why can't we have directional, projected magnetic forces ?"
] | [
false
] | [deleted] | [
"The ((cͻ)) shape of magnetic fields is a basic property determined by Gauss' law. This law also rules out the existence of magnetic monopoles, so magnetic fields will always form closed loops.",
"I am not sure what exactly you mean by your first question... Electromagnetic radiation, like a laser beam, is both e... | [
"1) Because the strength of a field has a set dependence on the distance from the di-/multi-pole (with some anisotropic dependence, since multipoles aren't point sources). We can't change that without changing the fundamental laws of nature.",
"2) EM radiation propogates. It moves over time. Static fields do n... | [
"1) Because the strength of a field has a set dependence on the distance from the di-/multi-pole (with some anisotropic dependence, since multipoles aren't point sources). We can't change that without changing the fundamental laws of nature.",
"2) EM radiation propogates. It moves over time. Static fields do n... |
[
"Is the type of pheromone that bees/wasps use to mark a threat universal?"
] | [
false
] | If a hive marks a target to be attacked, does another hive recognize the signal and joins the attack? Also, how do ants react? | [
"I remember a note in an O chem lab that stated banana oil, isoamyl acetate, is used by honey bees as the pheromone bees use to signal other bees to sting. I wouldn't know about wasps "
] | [
"This is true when a bee stings, the barbed stinger will exit the bee's body and emit a pheromone that says there is an intruder here."
] | [
"In most cases, each species of bee/wasp will use a different alarm pheromone. This will work between hives but not between species. For example, honeybee alarm pheromone has been identified as isopentyl (2-methylbutyl) acetate. This is found in bananas (as the previous commenter mentioned) but not in high enough c... |
[
"How did astronomers think the sun worked before the discovery of nuclear fusion?"
] | [
false
] | null | [
"There were a few competing ideas but here is a summary of the ones I know of:",
"- The sun was very hot due to some past event and was gradually cooling down i.e. it didn't have an internal energy source.",
"- It was a material gradually collapsing under its own gravity. This gradual crushing was leading to he... | [
"By the 1900s-1910s atoms were suspected but decay or collapse as opposed to fusion or fission. Mme. Curie had already discovered Radium so it seemed a possibility."
] | [
"Oh you'll love this. My friends have a very old farm house that was part of their family for hundreds of years. This is a Google lens transcription from a very old science book (BOUVIER'S FAMILIAR ASTRONOMY - 1856) that I took a picture of the contents one day. You can buy a digital copy on Amazon, but this was a ... |
[
"Why is it difficult to stop peeing once you start"
] | [
false
] | It is somewhat uncomfortable to hold urinating for a length of time. But holding it is much easier than starting to pee, then trying to stop mid-urination. Does anyone know what physiological difference there is between holding off on the commencement of urination and the cessation of urination? Why would the former... | [
"The neural control of micturition",
" is a pretty good review, and is free on PubMed Central. I'd suggest reading it if you're interested in the topic, and figure 5 is relevant to your question.",
"There are two main muscle groups relevant: those that contract the bladder and those that close off the urethra. ... | [
"Fascinating, thanks!"
] | [
"We have 2 different nervous systems in our body… the autonomic nervous system is not something we can consciously control. Smooth muscle contraction/ relaxation is controlled by the autonomic nervous system, and skeletal muscle (what most people consider normal muscle) we do have conscious control over.",
"The m... |
[
"How or why does cancer \"spread?\""
] | [
false
] | null | [
"The cells rapidly reproduce, and those reproduce, and those reproduce. \nI think you see where I'm going with this. "
] | [
"Not necessarily. ",
"http://www.youtube.com/v/rrMq8uA_6iA&rel=0&hl=en_US&feature=player_embedded&version=3"
] | [
"Mikeypedia."
] |
[
"Considering water can carry electrical current, could we use water supply systems as data lines for internet?"
] | [
false
] | i only ask because it seems our fastest data lines are made of glass (fiber), and our aqueducts are pressurized already, so it would be lossless. any thoughts? it could give high speed internet to the planet with little cost. | [
"It actually is possible to make (bad) data lines out of water. However, the fact that (impure) water can conduct electricity is somewhat irrelevant in this context. For rapid data transmission you want to operate at high frequencies, which will permit a large bandwidth (or maximum rate of data-propagation), which ... | [
"In addition to ",
"/u/crnaruka",
"'s good response, the capacity to carry electrical current is not required for data transmission, the optical fibers you mention are a great example.",
"and our aqueducts are pressurized already, so it would be lossless",
"This is an incorrect assumption."
] | [
"Just like to point out that GHz electromagnetic waves are nowhere near infrared but on the long side of microwave. Transmission using RF is somewhat different than transmission using fiber optics. ",
"Water pipes might even make very passable waveguides for the low GHz range of it wasn't for the pesky fact that ... |
[
"How does an mRNA vaccine \"bypass\" self-vs-nonself identification in the immune system?"
] | [
false
] | My (limited) understanding is that normal, healthy cells pickup the mRNA and process it through the normal protein synthesis pathway, just as though the mRNA had been transcribed from DNA. It is then presented on the surface (?) of this normal, healthy cell. I don't understand where in the process it then realizes th... | [
"T cells, one of the body’s various immune system cells, are “educated” in the thymus on what is self vs. non-self. This happens by the body’s proteins being presented to the adolescent T cells, and if they react strongly to our self antigens, they are removed from the process and destroyed so they don’t cause auto... | [
"Your T cells are reactive to a specific antigen. You have tons of different T cell clones that are each reactive to a separate antigen through different T cell receptors and can only be activated by that antigen. So T cells aren’t telling whether any given antigen is self or non self, but are simply detecting whet... | [
"While the comments about negative selection of T-cells by other commenters is accurate, this doesn't answer the question.",
"**** Does the hijacked cell suffer damage that triggers the immune response?)*",
"****)*",
"",
"The mRNA vaccines have a lipid \"nano\" coating that protects the mRNA from exposure ... |
[
"Are Mosquito Effected by Drug Content in Blood?"
] | [
false
] | If someone takes medication like Aderall, and then a mosquito sucks their blood, does the drug (amphetamines in this case) have any effect on the mosquito sucking it? Would a mosquito become drunk from drinking blood with a high alcohol content? | [
"It's more accurate to say we have receptors that THC happens to react with.",
"The Google link is not sarcastic, I just don't know enough to answer your question about the receptors, and Google has plenty about it.",
"https://www.google.com/search?q=thc+receptors&oq=thc+receptors&aqs=chrome..69i57.3681j0j7&cli... | [
"If the question is does the mosquito have some potential interaction with these drugs. Yes. It's actually been shown that the blood of people on the anti-parasitic drug Ivermectin is toxic to mosquitoes even. They do digest the blood in some sense and so yes things dispersed within it can effect them. ",
"I... | [
"No, female mosquitoes have to supplement their diet with blood to provide the necessary protein for egg development. It is only the female mosquitoes that bite though."
] |
[
"Is there a finite amount of energy in the Universe?"
] | [
false
] | I know that mass is related to energy through e=mc but is there a finite amount of energy/mass in the universe? | [
"Depends - if the Universe is infinite, then quite possibly. If the Universe is finite, then almost certainly not.",
"The thing is, the Universe as a whole isn't something we can study - there's only a finite bit, the ",
", from which light has had time to reach us. Everything outside that hasn't had time to co... | [
"Wouldn't it be the opposite? I'd think in an infinite universe the amount of mass-energy has to be similarly infinite or the Copernican principle wouldn't hold. "
] | [
"There's absolutely no basis for extrapolating the Copernican principle to an infinite Universe. It holds very well for the observable Universe, but there's no reason - except perhaps some very vague and poorly motivated aesthetic reasons - to suspect that at some absurdly large distance away, say thousands or mill... |
[
"Will a non ferrous metal passing perpendicularly though an electric field feel any kind of resistance (magnetic maybe)?"
] | [
false
] | null | [
"Not 100% sure without reading some of my old textbooks but I would say yes slightly depending on the mass and velocity of the bullet and the current of the electric field.",
"I would advice to look into Maxwell’s stuff (the guy who united the two field into electromagnetism) and also look at the dynamo rule that... | [
"If the object (metal, non-metal, ferrous or non-ferrous) has an electric charge, then the electric field would exert a force on the object. If the object has no net charge then it shouldn’t experience any external forces due to the electric field.",
"I think you might actually be thinking about metallic objects... | [
"What about the induced charge? Would an electric field cause charge separation if the object is conductive? And would that charge separation lead to a net electric force in the field?"
] |
[
"Would a low-pressure, high volume, lightweight chamber have a buoyant force in air?"
] | [
false
] | Buoyant force increases with decreases in weight and increases in volume, so if you could create a large impermeable constant volume chamber with a vacuum inside, would it have a buoyant force in air? | [
"Helium and air have densities of around 0.18kg/m",
" and 1.28kg/m",
" respectively at STP. This means that each cubic metre of helium can support almost 1.1kg (1.275-0.179kg) under these conditions. A high vacuum, on the other hand, has a density of 0kg/m",
" meaning it can support around 1.3kg per cubic met... | [
"Everything has a buoyant force in air proportional to the volume of the object.",
"So all you need is for the weight of the object to be less than the buoyant force, but in practice this is extremely difficult to do with a vacuum chamber, due to the structural rigidity necessary to maintain a vacuum. This is wh... | [
"It certainly would have a buoyant force, however the weight of the shell would negate any of that and you'd be left with a chamber sitting on the ground.",
"There's a thorough discussion on this topic here: ",
"http://www.reddit.com/r/askscience/comments/g72pq/a_helium_balloon_floats_because_it_has_a_lower/"
] |
[
"Why didn't the H1N1 Pandemic affect the world as much as COVID-19 did and still is affecting it massively?"
] | [
false
] | null | [
"It was just luck in 2009. H1N1pdm09 has a lower R0 than SARS-CoV-2 and a lower morbidity/mortality rate, but that’s just the way it turned out. It was nothing people did. ",
"Both viruses spread widely within regional human populations before being detected (pdm09 probably took longer to be identified). Both pro... | [
"One important detail: a sizable chunk of the population over the age of 60 had some level of preexisting immunity thanks to a earlier pandemic. Which meant the most vulnerable population was protected which kept the IFR down."
] | [
"There are several reasons, but the biggest was that it wasn't nearly as deadly or debilitating of a virus.",
"Source: ",
"https://www.cdc.gov/flu/pandemic-resources/2009-h1n1-pandemic.html",
"The 2009 H1N1 infected ~60 million Americans, but only resulted in ~275,000 hospitalizations and ~12,000 deaths. This... |
[
"Does the wave function collapse if a robot observes it?"
] | [
false
] | null | [
"Thank you for your submission! Unfortunately, your submission has been removed for the following reason(s):",
"/r/AskScience",
"To check for previous similar posts, please use the subreddit search on the right, or Google site:reddit.com",
"/r/askscience",
" ",
"Also consider looking at ",
"our FAQ",
... | [
"https://www.reddit.com/r/askscience/comments/6gf44k/physicists_say_to_laymen_observing_a_quantum/dipv8pl/",
"https://www.reddit.com/r/askscience/comments/vrav2/in_quantum_mechanics_the_position_distribution/c576aj9/",
"All the previous answers I searched are kind of vague or maybe I didn't understand them. The... | [
"Those are better questions than the consciousness one (consciousness doesn't have anything to do with quantum mechanics). You should submit a new post along those lines."
] |
[
"How does the body “kill” COVID-19 if the person is asymptomatic and there are no medical interventions?"
] | [
false
] | I was taught that symptoms of disease (i.e. the seasonal flu) were your body’s attempt to kill the disease. How do diseases “die off” in your body if there are no symptoms or medical interventions? | [
"Your immune system is in all honesty quite powerful. It is also what causes the most damage if it overreacts. Having no symptoms does NOT mean that your body is not fighting the disease.",
"Think about what symptoms are. Cough is defined as the expelling of air from the lungs. This is done to clear them, prevent... | [
"The symptoms of the this disease ARE merely the result, loosely put, of your body fighting the COVID-19 virus. However not all fights are equal, and asymptomatic people have largely been successful in fighting the disease before it gets to the obvious 'illness' stage.",
"Your immune system is fighting things all... | [
"The symptoms that a person feels with they are sick are due to cytokines (i.e. TNFA, Interferon) that are released as alarm signals (often from dying or infected cells). They are less so a direct attempt by the body to kill the disease.",
"The main response to an infection is by innate and adaptive immune cells.... |
[
"Why is this Benzene resonance not possible?"
] | [
false
] | I was reading an example in my book that asked if the loss of the chlorine leaving group would be stabilized by resonance and couldn't understand why this resonance is not possible. | [
"The resonance structure you drew on the far right of your diagram would be extremely high-energy and thus very unlikely to be a contributor to the overall structure. It involves a tremendous amount of torsional and ring strain. You can try building a molecular model to prove this to yourself."
] | [
"The double bounds are no longer delocalized. One of the carbons has 2 double bonds with its 2 adjacent carbons. You have to have all carbons to have only one double bond and next to carbons containing double bounds. The cation is stabilized by this structure and you can predict reactions based on the movement of t... | [
"There are 2 major intermediates that will resonate between 3 cations. this makes it more stable than your more \"normal\" carbocation. Its not particularly related to your question. "
] |
[
"What caused this island vortex in Lake of the Woods?"
] | [
false
] | Found this while perusing google maps. If I were to hazard a guess, I'd say some sort of rotating glacier. Are there other examples or is this the only one? | [
"It's actually structure in the bedrock of the lake. The rocks in this area are extremely old and have been folded by tectonic action. This particular area has either been folded into a dome or a basin, exposing different layers of bedrock. Glacial activity has more or less planed the area flat, and differential er... | [
"Spot on. It's also a great opportunity to bring in the word ",
"peneplain",
". Most flat plains have a bottom covered in sediment formed by whatever it was the cut the plain in the first place. Peneplains are erosive features that expose much older bedrock. The actual structure getting eroded is almost certai... | [
"No, this one isn't an impact crater. You're right, this is just simple folding in extremely ancient terrain. I'm not really sure of the source of the folding, but it long predates any recent glacial activity. It may be related to the ",
"Mid-Continent Rift",
" or tectonic activity even before that. It's so far... |
[
"Bizarre cloud pattern I saw 2 days ago; any idea what might cause this? [photo]"
] | [
false
] | I was in Scottsdale, AZ, a couple days ago and noticed the clouds had a very distinct break between overcast and clear blue along a continuous straight line across the sky from horizon to horizon. Image: The left photo is facing roughly NE and the right photo is SW at about 3 PM. I've never seen clouds like this before... | [
"Fronts are a near-surface phenomenon, while these ",
"cirrostratus clouds",
" which occur above 18,000 feet (5500 m), so it is not related to a front. Really, it's ",
"not all that uncommon",
", although the fact that these are high-altitude clouds (where there tends to be less turbulent motion) probably m... | [
"I have see fronts cause a very distinct line between very cloudy and clear sky. Perhaps you were looking up when a particularly straight front passed overhead?"
] | [
"I think this is correct. I've seen similar clouds before and I believe it is because there is a precise line in the sky where the temperature and moisture level is different. More than likely caused by a weather front approaching."
] |
[
"What happens in your stomach when you get a stich while running?"
] | [
false
] | null | [
"Thank you for your submission! Unfortunately, your submission has been removed for the following reason(s):",
"You can find the basic answer with a google / wiki search. Please start there and come back with a more specific question.",
"If you disagree with this decision, please send a ",
"message to the mod... | [
"Thank you for your submission! Unfortunately, your submission has been removed for the following reason(s):",
"You can find the basic answer with a google / wiki search. Please start there and come back with a more specific question.",
"If you disagree with this decision, please send a ",
"message to the mod... | [
"Thank you for your submission! Unfortunately, your submission has been removed for the following reason(s):",
"You can find the basic answer with a google / wiki search. Please start there and come back with a more specific question.",
"If you disagree with this decision, please send a ",
"message to the mod... |
[
"How does alcohol test strips work? In particular the ones that test breast milk for alcohol so that the mother can make sure her milk is alcohol free before nursing? Would test strips that need saliva or urine will be able to work with milk?"
] | [
false
] | null | [
"It appears that different brands use different mechanisms but they are all fairly similar. Make a free radical from the alcohol that then interacts with a dye molecule (modifying the aromaticity), and then you can compare the colored strip to their standards printed on the bottle. One brand uses alcohol oxidase t... | [
"Wow, thanks! So if I read it correctly, the ones that test with saliva or urine can be used for milk? Because I am going to try them out. ",
"Now if they do not work, where do I go about finding a company / mfg in the USA that can make strips that react to alcohol in milk? "
] | [
"Obviously with something as sensitive as the chance of a newborn ingesting alcohol I would have to say only use strips designed for the exact purpose--your child's safety and long-term health and development is not an area in which it would be wise to try to save some money. And I believe that you can find the mil... |
[
"How does the composition of the atmosphere vary with altitude, if at all? [Earth Science]"
] | [
false
] | null | [
"Not counting clouds (i.e. water vapour), it is a pretty constant composition of Nitrogen, Oxygen, Carbon Dioxide (and some others) up to around 100km up. Thereafter, the density begins to drop at a much faster rate. This happens within the thermosphere and becomes more noticeable at the the exosphere boundary (abo... | [
"I don't think this is quite right. Above 100km or so the recombination rate is less than the ionisation rate, so you have decreasing amounts of H2, He, or O2, and growing amounts of H",
" He",
" and O",
" See the figure at the bottom of ",
"this",
" page. From this it's also clear that the density does n... | [
"Yes. True. I was referring to ratios, not overall abundance, but maybe the wording was a bit unclear. I also left out elemental Hydrogen, Oxygen, and Helium, so thanks.",
"And what I’m trying to say with reference to density is that it decreases with height quite steadily after a certain altitude, specifically w... |
[
"Is it possible to break the sound of roaring wind into its constituent frequencies?"
] | [
false
] | null | [
"Yes, it's easy to record the ",
"waveform",
" of wind, i.e. the amplitude as a function of the time, and then to take its ",
"Fourier transform",
" to get the spectrum. The spectrum then shows exactly what you are looking for, the distribution of frequencies in the original sound. What is more interesting ... | [
"It is possible (rather trivially, actually) to break ",
" sound into its constituent frequencies. Record the signal, pass it through a Fast Fourier Transform, and voila. The ability to break down a sound into a sum of harmonic frequencies is a fundamental part of digital signal processing for audio application... | [
"I have a question about that spectrogram you linked. What is on the x axis and why are there vertical gaps in the speech pattern?"
] |
[
"How is a speaker able to vibrate simultaneously at a multitude of frequencies, especially those that are disharmonious? Why doesn't it turn into a muddy noise?"
] | [
false
] | null | [
"The only important quantity is the sum of the individual sinusoidal waves at each frequency. As long as the speaker follows this overall shape, no information is lost.",
"For more information, search the archives for your question, it is asked frequently."
] | [
"Sounds can be combined additively. This is the ",
"superposition principle",
" for sound waves. To create a sound with multiple frequencies, you can simply sum a series of sine waves with those frequencies."
] | [
"Disharmonious is a psychological phenomenon (with some support in spectral space), but generally you can add waves together to form superwaves and then extract the components later with relative ease.",
"For instance, consider a pond where two stones have been dropped some distance from each other. Each stone pr... |
[
"Can/has the intermediate disturbance hypothesis theory been applied to humans, specifically economics?"
] | [
false
] | [deleted] | [
"Sorry for the crap title, I was trying to submit this between powerpoint slides in a biology lecture. ",
"This slide",
" is the foundation of my question. ",
"Also, not sure how to categorize this...econ or bio, since it's kind of in both?"
] | [
"Try googling Evolutionary Game Theory. It's an applied version of economics into the field of evolutionary biology. "
] | [
"It's a crazy cool field. If anything strikes your fancy let me know. I'll do my best to explain it but it's not something I'm particularly good at."
] |
[
"List of best documentaries for each stage of evolution from abiogenisis through to human evolution."
] | [
false
] | Hi Reddit, I am looking to compose a list of recent & recommended documentaries that deal with a specific stage of evolution and beyond. Explain the Big Bang Theory, how sun's & planets are made etc.? Explain Abiogenisis and how single cell organisms formed? Explain the transition to multi-cell organisms? Other stuff?... | [
"First Life with David Attenborough is absolutely top-notch, I cannot recommend it highly enough. It's not terribly comprehensive, but it makes plausible the progression from just-after-abiogenesis to modern animals, aided by some really mind-blowing examples."
] | [
"Interesting concept. I just got done watching The Cell Pt. 3, which covered abiogenesis to an extent, but wasn't really comprehensive. ",
"I'm not sure there even ",
" documentaries over each step, though. Books? Sure. Films? I'd be surprised. "
] | [
"THANKS! I cannot wait to watch this and I'm sure it will be included in the \"final list\"."
] |
[
"What causes the cyclical temperature variation over the holocene?"
] | [
false
] | In temperature reconstructions from ice cores, you get something a bit like . CO2 goes from about 200 to about 280, which is about 0.48 doublings. If the ECS is about 3°C per doubling, then due to the change in CO2, we should be seeing about 1.5°C of temperature increase. What is causing the 9°C of warming? | [
"I'd like to add to ",
"/u/zorbaxdcat",
"'s post. Firstly, you're looking at the Pleistocene not the Holocene! The Holocene is only the past ~11,700 years, since the end of the last glaciation.",
"Generally for the past ~800,000 years, it has been orbital eccentricity that has dominated the climate signal. Th... | [
"If you look up glacial and interglacial periods you will see that the interglacials correspond to the sharp spikes in temperature. On these timescales variations in solar insolation are important. For the melting of glacial ice, increases in summer insolation in the northern hemisphere are important. If you find a... | [
"Thanks for your response silver snake.",
"Does this mean that because of changes to continental ice sheets, that on a time scale of millennia, the climate sensitivity to changes in radiative forcing is actually much higher than the value reported from models and observations over periods under investigation with... |
[
"How does a \"loop sensor\" in a street work?"
] | [
false
] | In particular, if my car was parked over one when powered down, and then it's turned on, would it sense me? Or does it only detect "flux", meaning a -moving- vehicle passing over it? | [
"The inductive loop is a big, low power electromagnet, with no core (or with an \"air core\" if you like). It operates as an inductor coil normally and an electrical signal with a certain carefully selected frequency is circulated through it. When a conductor is placed within the electromagnetic field of the loop t... | [
"No, the loops themselves are not magnets; they're inductive coils. I used the refrigerator magnet analogy to demonstrate how one can feel a change in magnetic potential without movement. "
] | [
"changing magnetic field",
"But, if \"change\" doesn't require motion, what kind of a change does it sense?"
] |
[
"Can humans transmit hormones through skin contact?"
] | [
false
] | From what I understand, cell membranes are very permeable to hormones. Is it possible for one person to transmit a hormone like testosterone, epinephrine, or cortisol via skin contact? If so, would this amount be significant enough to cause slight physiological effects or possibly alter the mood of someone else? | [
"Hormones are internal organic molecules that influence cellular and metabolic activity - i.e., testosterone is responsible for how your body builds, retains, and maintains muscle mass and density; insulin regulates the uptake of glucose for cell work.",
"Pheromones, on the other hand, are external - as in they a... | [
"Endocrinologist here. This is a great question that hasn't been studied well enough and I've been wondering about it for some time. Contrary to some other comments, virtually all steroid hormones do indeed \"leak\" out of the body constantly, though at low levels. Specifically: there are measurable steroid hormone... | [
"Thank you. This is exactly what I was looking for. ",
"Its really incredible how much we don't know and how many seemingly obvious experiments have yet to be preformed, recorded, published, and verified. "
] |
[
"Can energy be divided infinitely?"
] | [
false
] | I understand that energy is quantized in the form of photons, but not all energy is photons. I wonder, is energy infinitely divisible? I have googled it, but to no cited avail. | [
"I wonder, is energy infinitely divisible?",
"According to current physics, Yes. If there was a smallest unit of energy, there would also be a smallest unit of mass (mass-energy equivalence). There would also have to be a smallest unit of velocity change/acceleration for a particle, corresponding to that particul... | [
"I wonder, is energy infinitely divisible?",
"Not according to current physics, no.",
"Did you mean yes? Because the rest of that paragraph you're explaining how we don't have a smallest quantity of energy, which is what we will expect if energy ",
" infinitely divisible."
] | [
"Whoops, yes, that'd be a mistake. Fixed"
] |
[
"Are hybrid cars actually worse for the environment?"
] | [
false
] | I've heard a lot of different things about hybrid cars and their batteries actually causing a larger environmental impact than conventional cars. Is there any evidence suggesting this is true? | [
"Ugh, that CNW study. It was severely criticized when it came out. For example:",
"Among its most flawed assumption: the average H1 Hummer is assumed to last 35 years, and travel 379,000 miles, while the average Prius is assumed to last only 109,000 miles over 12 years.",
"There were lots of accusations of a pr... | [
"This question gets asked a lot so I'm now starting a megapost I can just copy/paste into each new thread. Feel free to ask any questions and I'll address them here. ",
"Here is an article estimating the life cycle GHG emissions of PHEVs with lithium-ion batteries",
". They estimate, given the current very GHG... | [
"That CNW outfit hardly looks like a reputable research organization. ",
"Also they assume that a prius is only driven ~100,000 miles, while every hummer is driven more than 300,000 miles. Hardly a fair comparision."
] |
[
"if you're travelling at lightspeed, will it take 500 years to travel 500 lightyears ?"
] | [
false
] | null | [
"Speed of Light (in MPH) \n670,616,629 ",
"Speed of Voyager (first vehicle to leave solar system: \n38,610 ",
"At that speed, it would take about 17,400 years to go 1 light year. ",
"17,400 (years for 1 light year) x 500 (years) = 8.7 million years.",
"nvm"
] | [
"thats for the voyager though, if we could travel at lightspeed how long would it take ?"
] | [
"Hi postwank thank you for submitting to ",
"/r/Askscience",
".",
" Please add flair to your post. ",
"Your post will be removed permanently if flair is not added within one hour. You can flair this post by replying to this message with your flair choice. It must be an exact match to one of the follow... |
[
"sound from a continuous pressure"
] | [
false
] | Today I was whistling and was struck by the realization that when I whistle I continuously expel air from my body, which should result in a steady pressure difference. However, sound is an oscillation in pressure. This may hold for wind as well, as wind I believe is a flow resulting from a pressure difference. However,... | [
"Steady pressure creates what is called a DC (direct current) offset; simplified it means that you are shifting the baselines pressure. But when you whistle or blow any steady (DC) pressure over an opening, the size of the opening, the volume/length of the enclosed region under it, etc (like the shape of your mout... | [
"but this offset, or linear component, as well as the shape are time-invariant. So, though the introduction of the frequency domain in the discussion has given me some perspective, it is still not clear to me where the oscillations develop as this linear component as well as the surrounding areas are constant. "
] | [
"A continuous flow of air through a small hole (as in whistling) or across the mouth of a chamber (as when wind blows past your ear) can produce resonant waves, which are what you're hearing."
] |
[
"Why does air get trapped in the middle of ice?"
] | [
false
] | How does air become trapped in the middle of ice, surely there is no air pockets in the liquid so where does it come from? | [
"Air can dissolve in water to some extent, and when the water freezes, the air comes out of solution and forms bubbles.",
"See this research article for a more in-depth explanation: ",
"http://iopscience.iop.org/article/10.1088/0370-1328/77/3/327/meta"
] | [
"And water generally freezes from the top and edges/outside, so the air can't escape."
] | [
"As the water temperature goes down the solubility of air ",
" not decreases. ",
"https://www.chem.fsu.edu/chemlab/chm1046course/solubility.html"
] |
[
"Can I get adequate vitamin d from the sun through a typical house window in the winter months? Since all windows are not the same is there an easy way to tell how much UVB my windows let through and how long I'd need to match the recommended dose of 15min of direct sunlight?"
] | [
false
] | null | [
"No, glass will block the necessary UVB rays. ",
"http://nutrition.about.com/od/askyournutritionist/f/sunlight.htm",
"\"The amount of exposure also depends on the time of the year. In the northern hemisphere, the UVB rays are more intense during the summer months and less intense during the winter months. In fa... | [
"Still my favorite study on UVB exposure and Vitamin D levels: ",
"http://jcem.endojournals.org/content/92/6/2130.long",
"Researchers took a bunch of surfers from Hawaii with ",
" levels of sun exposure and demonstrated that vitamin D levels were variable enough that some of them would be considered deficient... | [
"Exposure calculator"
] |
[
"Does our ability to learn and retain information really worsen with age, and if yes, why is that?"
] | [
false
] | I just went back to school after dropping out five years ago. Being 21 now, the thought that it'd be harder to cram education into my noggin is quite disheartening. I tried to find numbers on this after hearing about the deterioration of your learning capabilities as you grow older over and over again, but my Google-fu... | [
"21? Sorry to be the one to tell you this, but you might as well pack it in at this point. You can probably still do simple crossword puzzles and play some bingo on Fridays, but you're not going to be able to handle much else with a brain that old.",
"I know you came here for science, rather than advice (or sar... | [
"Neuroscientist here, my lab does a bit with aging but it's not really my area so I'll give this a go. You have several typse of intelligences and memory systems. One such system is your fluid intelligence, this represents your ability to rapidly switch topics, hold many objects in your head, and do mental calculat... | [
":)",
"I realize that 21 isn't old, my question was if there's a gradual deterioration. As in, at age 8 you soak up a lot, less at 10, 12, 14, etc.",
"Since the difference from 16 to 21 is almost a quarter of my life, if the decrease would be proportional to age, it'd surely be significant, if not as severe as ... |
[
"Do we have any idea where the Big Bang actually occurred? Which direction should we look from here to see that point?"
] | [
false
] | I expect I'll get something like, "it occurred everywhere," but I hope that is not the answer. It seems to me that if an outside observer zoomed out far enough, he could observe the Big Bang, see the universe expand, and eventually, see the earth at one point, and see where the Big Bang occurred as another point. If so... | [
"If the big bang was an event that occurred at a point, then the universe wouldn't be homogeneous and isotropic. But it is. Thus we can conclude that the notion that the big bang occurred at a point is false. It's as simple as that."
] | [
"there are no observable locations \"outside\" of the universe. It's just not a meaningful place to refer to.",
"to be a little more clear: imagine a sheet of grid paper. Except instead of the grid representing 1 cm, the lines represent some length that's a function of time. In general, that length grows over tim... | [
"Yes, it's a not-perfect analogy, but keep in mind that there is no point ",
" where it started. Once you accept that, then you need to go only so far as to drop the third dimension from the balloon, because it's not necessary for this analogy.",
"Honestly, you'd need to learn a little bit about mathematical ob... |
[
"How/Why do all planets in our solar-system revolve around the sun in the same direction?"
] | [
false
] | null | [
"Most planets in a solar System are formed from one dust cloud which only spun in one direction. Then the planets agglomerated, and kept their momentum, so their orbits go in the direction the original dust cloud was spinning in. That is also the reason why most planets are in the same plane around the sun. Pluto i... | [
"There is an example of a moon with a retrograde orbit, ",
"Triton",
". Because of this Triton is thought to be a captured Kuiper belt object."
] | [
"If the object enters the planets gravitational pull with the right direction and velocity, it could get caught in orbit. Similarly to the way our spacecrafts slingshot around planets to using their gravitational pull to get an additional boost. Enter slightly too fast and and they slingshot out, too slow and the... |
[
"Why does glass (an amorphous solid) have such different characteristics than crystalline solids?"
] | [
false
] | Im currently reading a paper about how tardigrades use Intrinsically Disordered Proteins to survive desiccation. They argue it’s due to the vitrification of the IDPs. So I’ve been trying to look up and learn about why this is possible and found that glassy states aren’t an “official” phase, have changes in several prop... | [
"So, the main differences between an amorphous solid and crystalline is long range vs. short range order. This is basically saying that the crystal has a \"perfect\" structure that continues \"forever\" while the glass does not. That perfect structure has more distinct modes that can do things like absorb or transm... | [
"Amorphous solids can be thought of like 'frozen' liquids: the atoms want to line up in an ordered crystal to maximize their interaction energy, but need to rearrange themselves from the disordered liquid state. If you cool them down too quickly, though, the atoms don't have time to do this, and get stuck where t... | [
"A glass is like if you took a liquid at the molecule level and stopped time with little to no respect for the orientation of the molecules.",
"A crystal forms with a specific order, all things are oriented in the same direction (roughly, simplistically). "
] |
[
"What happens to the stored fat soluble vitamins (A-D-E-K) if you lose fat?"
] | [
false
] | If it gets used by the body in full, I'd like to ask a follow up: As far as I know Vitamin A is the one where the point of "too much" is reached soonest. Now if you have had a Vitamin A rich diet before the weight loss, would that reduce your personal RDA for that time? | [
"I can answer for Vitamin A. It's mostly stored as retinyl esters in the liver and therefore shouldn't change. The RDA is the same, regardless of weight AFAIK. ",
"I'll let someone else answer for the rest."
] | [
"The significance of the vitamins being \"fat soluble\" is more important for absorption. That is, one can be deficient in vitamin A, for example, by not eating enough food containing vitamin A (",
" deficiency). Primary deficiency only occurs with starvation. That said, it is common (1/3 of kids worldwide) but t... | [
"I didn't think that the property \"fat soluble\" of vitamins is more important for absorption. Except the vitamin A, that is stored in the liver, where are the others stored? I assumed it would be in between the fat."
] |
[
"Can there be a silent bomb?"
] | [
false
] | null | [
"Bombs work by transmitting mechanical stress through solids or the atmosphere. Pressure waves in the air is how we sense sound, so any kind of detonation with the potential to cause destruction in this way will produce sound. ",
"Edit: if you're talking about a broad definition of 'bomb', a device that releases ... | [
"Most nuclear weapons produce a flash of light and infrared light that can be dangerous or deadly and of course is produced at the speed of light. In the gap of a few seconds between the light wave and sound wave hitting someone it would appear silent."
] | [
"Yes. In space."
] |
[
"Biology - Evolution: Something my Girlfriend Doesn't Quite Agree With. Any help explaining?"
] | [
false
] | [deleted] | [
"Oh boy, that's a doozy. I refer people to the website ",
"Talk Origins",
" that goes into pretty good detail about the discussion over Creation Science and Evolution. That should be a good place to start."
] | [
"Well in the case of the Viceroy, the monarch butterfly's wing pattern isn't very unusual. If you look at ",
"close relatives",
" of the Viceroy you'll notice a similar cell arrangement.",
"From there, a chance passing similarity to the Monarch is enough to apply evolutionary pressure to look more like it. ... | [
"The way that I would explain it is this:",
"Life that seems to mimic other life is simply reaping the benefits of the trait displayed by the other form (convergent evolution). ",
"One thing that ",
" to be explained is that the evolution of life is ",
". If one thinks that life comes about by, lets say, a ... |
[
"Could a 9.0+ earthquake from the Cascadia Subduction Zone trigger an eruption of Mt. Rainier?"
] | [
false
] | I have read that CSZ has the potential to generate a megathrust earthquake (>9.0). Rainier is an active volcano fairly close to this spot. I imagine if both these events occurred simultaneously it would cause some serious havoc. | [
"No and no. No magma, not soft like buildings. ",
"More like a mile high landslide"
] | [
"The primary danger with Mount Rainier isn't an eruption, but rather that the mountain isn't \"solid.\" The mountain's interior is a soft clay which has been formed by the active hydrothermal system underneath and freezing/thawing expansion/contraction of it's 25 glaciers on top. Thus, the major threat is from the ... | [
"In general, triggering of volcanic eruptions by large earthquakes falls into the category of \"possible, but extremely unlikely\". As this page from the ",
"USGS",
" nice outlines, the times this has been demonstrated with some rigor it appears that movement on a fault directly beneath the magma chamber may ha... |
[
"Why do liquids \"hang on\" to an object when they pour out? (When pouring milk into a glass and it drips down the side of the carton, for example)"
] | [
false
] | null | [
"All fluids have cohesive and adhesive properties. Cohesive properties determine the strength of the tendency of the fluid to stick to itself and adhesive properties determine the tendency to stick to other matter. That is why glue is called adhesive. \nMilk has a weaker cohesive property and stronger adhesive pr... | [
"All fluids have cohesive and adhesive properties. ",
"Just a clarification: you mean all liquids. Gases are fluids, but gases don't exhibit the positive surface energy that implies cohesion."
] | [
"At a molecular level the liquids can form things like hydrogen bonds or other strong intermolecular interactions with the surface. If this is favorable you get that sticking. For instance glass typically has OH groups on the surface which water can bond to. If you were to use a surface that whose interaction w... |
[
"Is Serum Sickness an allergic reaction or something different?"
] | [
false
] | null | [
"Kinda. There are 4 types of immune hypersensitivity, allergy being type I. Allergic reaction is caused by inappropriately large reaction to certain antigens present in pollen, bee venom etc. Immunoglobulins E bind to these antigens and in turn activate basophils and mast cells which promote the allergic reaction."... | [
"Im not an expert, but I think its permanent. As soon as your body starts to develop antibodies, memory B cells are formed which are responsible for long lasting immunity. Once you develop hypersensitivity towards specific serum, you need to use either different serum or immunosupressive drugs."
] | [
"Is this type of hypersensitivity permanent or can the body become less sensitive over time or through exposure?"
] |
[
"What is Earth's energy capacity?"
] | [
false
] | All energy turns to heat in the end, and if we take solar energy coming to earth and turn that to electricity, the outcome won't add any more heat to Earth that what would have come anyway. But result is not the same if we use nuclear energy, fossile fuels or solar energy from outer space, because that will add heat to... | [
"There is no such thing as a limit, but unless you start adding energy on the order of petawatts (10",
" watt) the effect would be negligible. ",
"Currently the total yearly human energy consumption is around 150 Terawatthour, which converts to 17 terawatt. For comparison, the effect of Solar variation in the 1... | [
"A rough calculation we could use is the maximum total available solar radiation available to earth. Using the solar constant of 1.366 kWh per m",
" we can calculate that the maximum available energy to earth is the cross section area of earth and its atmosphere perpendicular to the sun multiplied by the solar co... | [
"Too much for what? For the planet to boil away? At a very simple, high level, the planet's temperature is that where incoming energy equals the amount of heat released into space. ",
"Assuming average surface temperature is 273 Kelvin and all energy out into the planet goes to the surface, you'd need to increase... |
[
"Can you identify this?"
] | [
false
] | null | [
"Hi ExoSkiller thank you for submitting to ",
"/r/Askscience",
".",
" Please add flair to your post. ",
"Your post will be removed permanently if flair is not added within one hour. You can flair this post by replying to this message with your flair choice. It must be an exact match to one of the foll... | [
"Human Body"
] | [
"Human Body"
] |
[
"Why don't all of Jupiter's gasses mix so that the planet becomes a uniform color?"
] | [
false
] | null | [
"Guy in the field here.",
"Convection is only rarely spotted in specific plumes - for the most part, the temperature gradient in Jupiter's weather layer is not steep enough to maintain convection. ",
"There is, however, what seems to be large-scale upwards vertical motion in the white \"zones\", and large-scale... | [
"Somebody in the field might have more recent information, but my understanding is that what causes the atmospheric bands on Jupiter is not fully understood. While the stripes have been attributed to ",
"convection",
", with the dark and light stripes corresponding to rising and falling gases (hotter gases ris... | [
"That happened within a couple of years.",
"Considering that stripe is several times larger than the earth, and the speed at which the change happened, the weather down there must be unimaginably violent."
] |
[
"Can we send a \"rover\" kind of thing to Jupiter to float around suspended by a balloon, taking pictures and samples?"
] | [
false
] | It's a gas-giant, right? Can some balloon float around in some layer there and just take pictures and samples? Seems like it would even use less energy than the ground-based Mars machines. | [
"Pressure is only a small part of the problem on Venus and easily engineered around, the high temperature is the big challenge. The Russian probes only had 2 hours of refrigeration capacity before overheating, they were not crushed.",
"For some perspective Venus atmospheric pressure is 90 atm while the pressure i... | [
"The Galileo Probe did something like this, but it parachuted down to see the different layers. Jupiter is huge so floating around any considerable distance would take a long time. The data returned for the cost would make it a hard sell as a budget item, so many other more interesting things to visit."
] | [
"The later Venera probes weren't crushed; their insides melted. The probe casings should still be standing on Venus today (",
"here's",
" a neat visualization of what Venera 14 should look like now).",
"I don't see how pressure would be a problem for a Jovian balloon. Shouldn't it naturally gain altitude due ... |
[
"Why is my salt leaving my salt shaker?"
] | [
false
] | The salt is slowly climbing up the wall of the shaker and out the lid. What chemical process is causing this to happen? | [
"Well what might be happening is a series of dissolution and depositions. The humidity dissolves a tiny bit on the side, salt disolved, then the water evaporates leaving it a bit higher up. Rinse repeat."
] | [
"Another comment explained it pretty well, the salt gets dissolved in moisture and recrystallised elsewhere.",
"But if you want to stop that happening you can put some form of dessicant like sillica, or more innocuous rice grains that can't fit through the hole in the salt shaker. These will adsorb moisture, or y... | [
"Very cool. Thanks!"
] |
[
"How do you cool something with lasers?"
] | [
false
] | I was reading the following article on Wired: ...when I came across this sentence: At first, the ions will vibrate in an excited state, but diode lasers like those found in DVD players will be used to gradually scatter away their extra kinetic energy. According to the group’s calculations, the ion ring should settle in... | [
"The most popular form of laser cooling is ",
"Doppler cooling",
". Doppler cooling works on the principle that electrons have discreet energy states, thus the laser cooling has to be tuned for the exact system you want to cool. Here is how it works.",
"Imagine you have a nice, cold system. The electrons shou... | [
"\"....electrons have discreet energy states....\" ",
"ARRRGH! Electrons are a bit circumspect, sure. But their energy states are ",
". ",
"Very nice explanation otherwise, though. "
] | [
"Well they ",
" don't like letting you know where they are exactly..."
] |
[
"How do the joints of a hummingbird deal with all the wear?"
] | [
false
] | [deleted] | [
"Actually a hummingbird has a completely different joint structure than other birds. Most birds have a joint that bends and folds allowing them to move their wings up and down. they have a ball socket joint like we have in our shoulders and hips allowing them to move in a much smoother motion. Also on top of that f... | [
"AFAIK: a healthy human shoulder does not wear down under normal conditions. You have to have an underlying problem for the shoulder to start breaking down. ",
"Joints need a little (",
") stress and motion to recover and stay healthy."
] | [
"Cartilage doesn't \"wear\" per se. In normal use, the collagen matrix is replenished by healthy chondrocytes. Arthritis is caused by inflammation within the joint that causes chondrocytes to either die or undergo transdifferentiation, resulting in degredation of the collagen matrix and eventually degredation of th... |
[
"Why can't I have plastic bottles at places that smelt Aluminum?"
] | [
false
] | I'm told it can cause an explosion, but I'm curious as to the mechanism? How dangerous is it to have Aluminum cans and reclosable soda bottles near an aluminum plant, and why? | [
"if the rule is for inside the facility it can be incase you drop it into a vat of\nmolten metal. The water bottle will melt and expose all the water which will immediately vaporize and all that steam will cause an explosion of molten metal. Similar to how water in hot oil can cause it to pop and burn you - and tha... | [
"Former aluminium smelter employee. This is standard on all aluminium smelters. Glass bottles, cans, Tina cans, anything made of metal or glass that can store water are banned site wide. Not. Misunderstanding like someone wrote below. If they get into a reduction cell accidently you are probably looking at 100M... | [
"I have no evidence to support this thought, but it would seem to me that aluminum foundries don't want non-aluminum containers because they want to promote the use of aluminum by their employees.",
"That sounds like tinfoil hat thinking. Could I perhaps interest you in a superior aluminum foil hat?"
] |
[
"Similarities between the 2nd Law of Thermodynamics and the Principle of Least Action?"
] | [
false
] | In my Thermodynamics and Statistical Mechanics class today, the professor was talking about how the 2nd Law is one of the only ones which isn't really derived, and is simply based on observation rather than logical necessity, and it got me thinking. From what I know, the 2nd law is basically a statement about the direc... | [
"Wellll, I think you're inferring more similarity than is really there.",
"The classic example of entropy in action — which I know you've heard; this is for the audience — is of a box full of coins. There are three possible states for the box to be in, right? All coins heads-side-up, all coins tails-side-up, and ... | [
"Sure there is, but remember action is a scalar; it has units of energy-time. For any possible trajectory between two points in space (or more properly, events in spacetime) we can integrate the Lagrange density d⁴",
" and get a scalar value. So the phase space for action is over trajectories, and it's just one-d... | [
"I'd definitely say that entropy always increasing ",
" derived mathematically and based on logical necessity. I wrote ",
"this earlier",
" describing (qualitatively) what goes into the argument for entropy. I'm not a great expert on thermodynamics, so I'll leave the state-variable/phase-space/action argument... |
[
"[Astronomy] Do the planets actually all orbit the sun on one plane? *more detailed*"
] | [
false
] | In most models of our solar system, the planets all orbit on the same plane. To me, this seems wrong because the sun is a sphere. In my mind, I see the planets orbiting the sun like electrons orbiting an atom. Am I wrong? Are the models we are taught in school just simplified so that we can conceptualize the solar syst... | [
"They orbit in ",
" the same plane. Each planet has an ",
"orbital inclination",
" relative to the Earth's orbital plane. The highest is Mercury's at 7°. If Pluto were still a planet, it would be the highest at 17°."
] | [
"The planets do orbit the sun in one plane. The sun is a sphere (actually an oblate spheroid, but pretty close to a sphere) because it's own gravity pulls it into that shape. As the universe was forming, though, there was a protoplanetary disk around the sun, which maintained that shape due to its angular momentum.... | [
"A less geocentric reference is the Solar System's ",
"invariable plane",
". The total angular momentum of the solar system is perpendicular to this plane by definition. Unlike the ecliptic plane, this one is not going to change if Earth is perturbed gravitationally by the other planets (unless there is an extr... |
[
"If one parent had a gamete that was missing a chromosome (turners syndrome) and the other parent had a gamete with an extra chromosome (down's syndrome), would they be able to form a normal healthy baby?"
] | [
false
] | [deleted] | [
"No, because each condition affects different chromosomes, responsible for different information. Down's syndrome occurs when you have 3 chromosomes in the 21st set, where as turners syndrome is a malfunction of the X chromosome in the 23rd set.",
"Sources:",
"http://www.ds-health.com/trisomy.htm",
"http://w... | [
"First, human chromosomes vary greatly in size, and are numbered according to approximate size, with chromosome 1 being about the largest. The X chromosome is also one of the largest. \nSecond, because humans are normally diploid, the cell expects there to be a double dose of each gene in the genome. When one chrom... | [
"Most of the time they are non-viable. Miscarriages are pretty common (up to 30% of fertilized eggs), often due to this. "
] |
[
"How i can calculate the height at sea level if I only have presure or temperature?"
] | [
false
] | How i can calculate the height at sea level if I only have presure or temperature?... how i can calculate these empirically? | [
"In the real world, this is complex. Low in the atmosphere and making a bunch of assumptions, the pressure is determined by p=ρgh where ρ is the density of the atmosphere (~1.225kg/m",
" ), g is the gravitational acceleration (9.81m/s",
" ) and h is the thickness of the atmosphere above you in meters.",
"Befo... | [
"R is a constant and all the others are variables in your scenario which makes it difficult...there is a barometric equation but it's not any less complex, because it's based off the gas law as are a lot of other stuff. Ph=Pe",
" Ph= pressure at height. P= pressure at sea level, e is a constant, m is the mass of ... | [
"Pressure is pretty easy, at 1atm you are at sea level. Anything less and you are above, anything more and you are below sea level. The exact empirical formula eludes me right now but I'm sure Google can find that for you. You should also note that the coefficient of height to pressure changes significantly if you'... |
[
"How come men go bald over time, and women don't? Also, why don't they lose their eyebrows and eyelashes?"
] | [
false
] | null | [
"Women can, but i think you are talking about androgenic alopecia (yes, look what the name means!).",
"Its caused by Dihydrotestosterone (DHT) because in some people (its genetics again - latest i heard was a gene called SOX21, look it up), hair follicles are sensitive to this hormone, and shrink in response.",
... | [
"I get it! I actually get it! Thank you. "
] | [
"Just off the top of my head, women have fewer androgen receptors in their scalp (DHT, an androgen, is responsible for male balding), and they have less androgen hormones in general, and they have more estrogen, which has a somewhat opposite effect on hair follicles as DHT does. Thus, women tend to bald less severe... |
[
"What factors cause/increase the chance of rain?"
] | [
false
] | I am a student studying software and im playing around with a simple machine learning library. I want to create a small program that can predict if it is raining or not by looking at a list of numerical attributes that may suggest rainfall. Im dont have much knowledge of meteorology, what atmospherical attributes am i ... | [
"Sure, there's a bunch of factors which produce rain: I'll start with three.",
"Humidity / dewpoint. Air itself can hold a certain amount of air. You can inject more and more water into air and it'll absorb it. However, once you reach 100% saturation, then it'll precipitate out, in the form of liquid water — rain... | [
"I recently read that mushroom spoors are sufficiently dense over a forest to increase the rainfall by being available for the rain drops to form around. So you will need to factor in mushroom spooring season in your equation."
] | [
"Barometric pressure is a good place to start. People have been using barometers to predict weather for a long time.",
"Professional meteorological modeling is quite a complex task, taking into account things like sea surface temperatures and pressures in defined regions of ocean. For example Australia's weather ... |
[
"What are some really basic things about the human body than science cannot yet adequately explain?"
] | [
false
] | null | [
"Consciousness isn't exactly basic but it is one of the things science can't (maybe yet) explain. Currently a hotly debated subject within Philosophy of Mind, some camps argue for the mind being non-physical (David Chalmers) but most are trying to find a theory reconcilable with a naturalist view."
] | [
"The internet is definitely physical. It's just abstract. It runs on wires, elections, magnetic data, silicon transistors, etc. "
] | [
"What is memory?",
"We had the notion of genes decades if not centuries before the discovery of DNA, then we found out that DNA is where genes lie... although it is a bit more complex than this since with 20000 genes we make 1 million proteins.",
"Where are the insticts located? Why dogs make a circle before si... |
[
"What would happen if everyone in the world were to jump at the same time?"
] | [
false
] | [deleted] | [
"Jack shit."
] | [
"Newton's third law: the momentum of pushing off the earth would equal that released back into the earth upon landing (minus a very small amount in the form of air resistance and sound). So any gains from the landing would be canceled out by losses in the pushing off.",
"Furthermore, humans are very, very, very s... | [
"The zeroth order approximation is nothing: assume everyone's evenly distributed around the world and jumps perfectly straight of the ground. The first order approximation is a very brief extremely extremely tiny change in momentum that will be equally canceled out by people landing back on its surface (this approx... |
[
"When you run and get a stitch, what is it and why is it so painful?"
] | [
false
] | null | [
"The phenomenon is called exercise-related transient abdominal pain (ETAP). Despite being a common experience, to my knowledge, the underlying cause is unknown.",
"For review: ",
"https://link.springer.com/article/10.1007/s40279-014-0245-z"
] | [
"I do not know why. But for me a sure fire way to avoid them is not to eat for at least 3-4 hours beforehand. When I run in the morning, 10+ hours since last meal, I never get the stitches. When in the afternoon when eating within the window, I managed to get some. And it wasn't anything heavy, just few hundred gra... | [
"I would guess that it comes from issues transporting glucose to your muscles properly. When you eat, you liver does a huge job at converting it to glycogen, which can sit in the body as backup fuel. Your muscles contain some glycogen, which is broken down into glucose when you begin to exercise while more is sent ... |
[
"Why did my lemon juice ice cubes spark in the microwave?"
] | [
false
] | When our lemon tree yields more lemons than we can handle, we sometimes freeze straight lemon juice in ice cube trays. Tonight my wife tried to melt pure lemon juice ice cubes in a bowl in the microwave, and kept getting sparks (even though there was no metal in the microwave). The microwave isn't failing; there were n... | [
"Microwaves can’t heat up solid‐phase water (i.e. ice) as effectively as liquid water because microwaves do not resonate with ice the same way they do with liquid water.",
"This is why there are special defrost cycles on many microwave ovens. Otherwise, as soon as a pocket of ice melts, it is heated more effectiv... | [
"Could this be related to ",
"grape-ogenic plasma",
"?"
] | [
"If you take a grape and slice it almost all the way through so it is sitting open in two-halves with a slight piece of skin joining it at the bottom then throw it in the microwave, you will see sparks arc between the two halves. This may be related.",
"[",
"ref",
"]"
] |
[
"Just watched the Sixty Symbols video on LHC and that it has discovered one particle; Is there any major physics theories that it has categorically disproved?"
] | [
false
] | null | [
"\"categorically disproved\" is not a term used in physics",
"Instead, they say stuff like .. within the range of energies studied, we have seen no statistically significant evidence",
"Many theories have failed the test, but the most significant one is Supersymmetry, a theory that predicts that all known parti... | [
"I can add to this. Loop diagrams allow the probing of much higher energies virtually. So while you may not be directly observing super partners the loops with these super partners will effect the calculations and measurements of various decays. So you look at the reactions and calculate with and without these loop... | [
"As someone who used to work in HEP-ex on SUSY/new physics stuff, I would add my skepticism of those (not saying ",
"/u/MpVpRb",
" is one of them) who claim that a more powerful accelerator would do us any good. This is obviously anecdotal, but after the initial results from Run II came out, a lot of the younge... |
[
"When photons hit our eyes, do we see them as waves or particles?"
] | [
false
] | [deleted] | [
"I'm under the impression that light exists in a superposition state as both a wave and a particle, but then collapses into one or the other when observed.",
"Wave-particle duality is an attempt to assign what seem like \"natural\" mutually exclusive classifications to a system we cannot intuitively understand. L... | [
"light exists in a superposition state as both a wave and a particle",
"This is your main misconception. Like ",
"/u/I_Cant_Logoff",
" says, the quantum-mechanical object is described by a wavefunction that can be ascribed both wave-like and particle-like properties. This holds for any wavefunction and has no... | [
"which removes the individuality of the photon: it must now be viewed as part of a multi-body quantum system",
"Is that a good metaphor for any quantum collapse? \"removing the individuality\" and \"becoming part of a multi-body system\"."
] |
[
"If you roll a die twice under the exact same circumstances, and I mean every possible thing is the same, would it produce the same result?"
] | [
false
] | I had always thought that yes, it would because if everything is the same then it couldn't possibly produce a different result. However someone said that this was untrue due to quantum mechanics, Being unsure of what exactly those are or how they affect things I wasn't sure. | [
"This would indeed be untrue for simple quantum systems, the same initial system can indeed yield different outcomes. But dice and coins are incredibly complex quantum systems which have the funny behavior of behaving classically. A physical coin should, given the same initial conditions, ",
" land the same way e... | [
"That's why the non flipper calls it ",
" it's been flipped and before it lands. The flipper can try for heads or tails, but it won't help him unless he has some idea what the non flipper is going to call."
] | [
"Persi himself took it one step further and trained himself how to always flip the same result by ",
"."
] |
[
"Why do we take oral antibiotics for localized infections?"
] | [
false
] | Considering how important the microbiome all over our bodies is, why is the go to treatment for any infection oral antibiotics that hit the entire body, rather than something, say, injected directly into the site of the infection for a cyst or something? I know topical antibiotics exist, but don't work for anything too... | [
"There are some antibiotics (some penicillins and cephalosporins) which are administered intramuscularly, however they are administered for specific (non-wound) indications. From a pharmacological standpoint, PO dosing offers the benefits of being less painful and enable the patient to receive treatment without nee... | [
"Welcome. As regards the spectrum of activity, while there are broad spectrum agents, they are mostly given IV. Even the narrower spectrum agents, such as first and second generation cephalosporins are active against multiple genera because they target shared bacterial metabolic/reproductive pathways. Drugs which a... | [
"So if they were to deliver one or a series of antibiotic shots right into a wound it would still hit the gut anyway? If that's the case I guess it makes sense to just do oral therapy. Do antibiotic ointments have completely different modes of action to avoid this? Or can even the creams hit gut bacteria?",
"Than... |
[
"How does it look like for a twin who watches his other twin go in twin paradox?"
] | [
false
] | null | [
"Check out the Wikipedia article:",
"http://en.wikipedia.org/wiki/Twin_paradox#What_it_looks_like:_the_relativistic_Doppler_shift"
] | [
"Thank you, but I feel like it wasn't the right answer I was looking for...\nI know the traveler would seem to be red shifted away, but-\nHow in general, simply would it look like for a twin on Earth watching his other twin traveling for a few years? ",
"If he would looked like he went and came back in a second ... | [
"Did you read the section? The discussion is more than just redshift. It takes into account both transit time and time dilation to give the apparent image one would receive.",
"Edit: Rereading your post I'd suggest you read the entire article, as it's likely you have some misunderstanding about the twin paradox t... |
[
"Do humans and viruses form symbiotic relationships?"
] | [
false
] | Clearly humans and bacteria have quite a symbiosis. Is this also the case for viruses? Do other animals rely on viruses to carry out any of their physiological processes? | [
"There aren't any known life forms that rely on viruses for vital physiological processes. ",
"However, we humans, in our continued effort to bend nature to our will, have started the process of learning to use viruses for gene therapy to repair or replace dysfunctional genes in order to treat and/or cure geneti... | [
"There is ",
"growing evidence",
" that many of the genetic regulatory elements in our genome are actually relict viruses. However, since these are no longer replicating viruses, I'm not sure if this can be defined as symbiosis."
] | [
"Actually, only the shittiest viruses do this. The most effective viruses leave every cell in thier host perfectly healthy, enabling that host to infect as many new individuals as it contacts as possible. Many viruses have evolved mechanisms that allow them to gently bud off from the host cell, leaving it alive. ... |
[
"What causes Gravity? The Higgs Boson or the Graviton?"
] | [
false
] | I'm not sure which is correct anymore. The Higgs Boson is said to cause gravity by interacting with fundamental parts of matter in certain ways. This interaction gives matter their "mass". On the other hand, I've also been under the impression that the Graviton is the guage boson for all matter-- this would imply that ... | [
"The Higgs boson does not cause gravity, nor is it responsible for mass.",
"The Higgs boson is an artifact of the Higgs field. One of the other artifacts of the Higgs field is that there is a non-zero Higgs field throughout space, and ",
" (not the Higgs boson) is what's responsible for the mass of such things... | [
"GR only explains gravity classically; it does not explain how to treat gravity quantum mechanically."
] | [
"This is explained within general relativity."
] |
[
"If one's eyes were removed from their socket what's the 'Plan A' scenario for giving him back vision?"
] | [
false
] | After watching Event Horizon, it's got me wondering. What would the visual cortex perceive if my eyes exploded from pressure in space? What would be the last thing I'd see? Would the pressure immediately pop them? Would I have to shut my eyes to keep them in? o.O? Would there be a gradual warping of vision, until every... | [
"What would be the last thing I'd see?",
"Similar as if you start pushing on your eyes. Lots of random stars/streaks and then blackness.",
"Would the pressure immediately pop them?",
"Nope. The eyes have a membrane which can hold tension. They would dry out and you would pass out due to lack of oxygen to y... | [
"After your eyes popped you would be fucked. If there was damage to the retina due to drying you might be able to have a transplant.",
"http://www.ted.com/talks/sheila_nirenberg_a_prosthetic_eye_to_treat_blindness.html"
] | [
"To add to this, while it currently is not feasible as a full scale technology, implants directly into the eyeball or alternately into the occipital lobe have shown amazing results. ",
"There are a myriad of issues still needing to be solved but this research is promising to say the least.",
"http://www.youtube... |
[
"Why do we feel like eating certain foods at times over others?"
] | [
false
] | For instance, sometimes people may want something crunchy, or get even more specific by naming exactly what they feel like eating. Does it depend on the climate? If so, what changes occur in our bodies to tell our brain that we crave a certain kind of food? | [
"there was an experiment done many many years ago where they basically let a large group of babies choose which food to eat whenever they wanted and however much they wanted. apparently they kept themselves healthy and ate a balanced diet. I'll try to find it"
] | [
"Someone who knows what they are talking about can back me up on this one. I saw a video that said your body and brain together knows what nutrition you are running low on and will pick an item that has the nutrition that you need. This is why some foods will \"sound good\" at certain times. I'm sure there are many... | [
"This is not true at all. See my comment ",
"here",
"."
] |
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