| Since light stops penetrating water at 1000 meters deep and the deepest freshwater lake is 1642 meters deep(both according to Google), is there an equivalent to deep sea creatures for freshwater? Posted: 23 Jan 2018 06:54 AM PST |
| What makes activities such as reading and crossword puzzles effective at helping cognitive function, but not "brain game" apps and their exercises? Posted: 23 Jan 2018 05:02 PM PST I am reading about Lumosity and their settlement for making false claims about their product and am curious what the difference is between their "games", that seem to require focus and cognitive function, and other activities such as sudoku and reading, which we know can help prevent cognitive issues. submitted by /u/Riff_28 [link] [comments] |
| Ask Anything Wednesday - Biology, Chemistry, Neuroscience, Medicine, Psychology Posted: 24 Jan 2018 07:07 AM PST Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Biology, Chemistry, Neuroscience, Medicine, Psychology Do you have a question within these topics you weren't sure was worth submitting? Is something a bit too speculative for a typical /r/AskScience post? No question is too big or small for AAW. In this thread you can ask any science-related question! Things like: "What would happen if...", "How will the future...", "If all the rules for 'X' were different...", "Why does my...". Asking Questions: Please post your question as a top-level response to this, and our team of panellists will be here to answer and discuss your questions. The other topic areas will appear in future Ask Anything Wednesdays, so if you have other questions not covered by this weeks theme please either hold on to it until those topics come around, or go and post over in our sister subreddit /r/AskScienceDiscussion , where every day is Ask Anything Wednesday! Off-theme questions in this post will be removed to try and keep the thread a manageable size for both our readers and panellists. Answering Questions: Please only answer a posted question if you are an expert in the field. The full guidelines for posting responses in AskScience can be found here. In short, this is a moderated subreddit, and responses which do not meet our quality guidelines will be removed. Remember, peer reviewed sources are always appreciated, and anecdotes are absolutely not appropriate. In general if your answer begins with 'I think', or 'I've heard', then it's not suitable for /r/AskScience. If you would like to become a member of the AskScience panel, please refer to the information provided here. Past AskAnythingWednesday posts can be found here. Ask away! submitted by /u/AutoModerator [link] [comments] |
| How do microSD cards work? Posted: 23 Jan 2018 08:24 PM PST SD cards already seemed pretty insane to me, cause you are fitting 512 gb of data on a drive the size of your thumb. But seeing that there is now a microSD card that can fit 512 gb of information on a card the size of your fingernail, that has to beg the question, how do microSD cards work, and how the hell can it fit half the size of my hard drive in a space almost 10 times smaller? submitted by /u/ezjie [link] [comments] |
| How does a Launch Loop work exactly? What in it is sending objects into orbit? Posted: 24 Jan 2018 05:39 AM PST |
| Why are our brains so high up in our bodies? Posted: 23 Jan 2018 08:09 AM PST Since blood is heavily influenced by gravity, and the brain requires a lot of oxygen to function properly, why do we have our brains in the highest part of our body, as it takes a lot of energy for great amounts of blood to be pumped all the way up there? submitted by /u/GCallen [link] [comments] |
| If you blow too hard on a recorder, it plays completely the wrong note. Why? The same holes are open as when you blow correctly. What's going wrong? Posted: 23 Jan 2018 07:34 PM PST |
| [Orbital Mechanics] What does burning radial out/in do? Posted: 24 Jan 2018 07:22 AM PST Hi all, I've begun playing around with Kerbal Space Program and there are some things that are unclear to me when it comes to orbital mechanics. In orbital mechanics, speed and altitude are linked: a satellite or a ship orbits a body at a given altitude and a given speed (at least that's what I understand). If I increase the speed (by burning prograde) I will increase my altitude and vice versa. I also understand that if I burn normal (or antinormal) I increase (decrease) the angle of my orbit: this seems easy to understand when summing speed vectors. What I don't get is burning radial out / in. Suppose I'm orbiting the body at 2000m/s @ 100km. If I burn radial out (away from the body), I will increase my altitude (because I'm providing thrust in that direction). Then if I stop burning, let's say I'm now at 110km altitude, what happens? Well I'm at 110km altitude for which the orbital speed is supposed to be 2100m/s (for instance, haven't made the calculations), but I'm still going 2000m/s because I haven't accelerated in the direction I'm orbiting. So the ship / satellite should begin to lose altitude to get back to 100km, right? Or am I missing something? Another question that is related: how is it even possible to do orbital rendez-vous? I mean if I'm trying to rendez-vous with a satellite orbiting the body at a certain speed (and thus altitude). If I come from "under", meaning if I have a lower altitude, then I have a higher speed. So I'm "gaining" on it. Suppose I time my prograde burn so that I rise to the target altitude (and speed) but I'm a few kilometers ahead of the target. Then I'm toasted right? Because if I'm a few kilometers ahead of the satellite and try to slow down a bit by burning retrograde so that it can catch up on me, then I'm also lowering my orbit. I get that we have computer models that make very powerful computations, but when we are talking about docking a ship to the ISS, I suppose the computer models cannot compute a single burn that will place the ship at exactly the correct position and speed, at mm/s and mm accuracy. So there has to be adjustment burns, even minor ones. But since altitude and speeds are always linked, how does one position exactly at the correct speed and altitude? Sorry if this is obvious, but something's not ticking with me on this one :/ Thanks in advance :) submitted by /u/nschoe [link] [comments] |
| Why do our eyes tear up when we’re choking? Posted: 23 Jan 2018 08:31 AM PST I had the fun experience of choking on a small piece of cereal this morning and I noticed my eyes automatically got watery when I started choking. What do tears have to do with breathing? submitted by /u/lovethecrazies [link] [comments] |
| Why do LHC's two pipes placed horizontally to the ground ? Posted: 24 Jan 2018 06:13 AM PST I had recently the opportunity to ask questions about the LHC to experts, and few questions pops up only after the meeting. One of the question is the following : there is two parallel pipes, crossing only at particular places (where collision detectors are, obviously). According to drawings and explanations i found, these two pipes are arranged so they are side by side (they have the same altitude). This seems odd to me because (1) this makes the outer pipe longer than the inner pipe, since they both follow the same line and (2) needs more complex arrangement of the magnets that curves the particles trajectory. This probably have a consequence on computations and engineering implementation. On the other hand, making them stacked up would not change anything about how the LHC works, but would counteract the one-is-longer-than-the-other effects. So, what didn't i understood ? submitted by /u/elucator [link] [comments] |
| How do electrons distribute themselves in a cross section of a wire, when they move through it? Posted: 24 Jan 2018 06:10 AM PST In addition, would it be possible to measure differences in electron density (or probabilities of electron distribution) through a cross section of a wire with sufficiently sensitive equipment? submitted by /u/mechdoc [link] [comments] |
| How much do we expect noise to drop in major cities with the rise of electric vehicles? Posted: 23 Jan 2018 04:53 PM PST Starting to see more electric vehicles on the road and some point they will replace current conventional vehicles which are rather loud. Will there be a drastic drop in noise or will it remain around the same? submitted by /u/contracthitman [link] [comments] |
| Do parasitic worms, such as nematodes, have immune systems? Posted: 23 Jan 2018 08:36 PM PST I was shown a video of Eosinophils attacking a nematode, clustering around it and entering the worm. Here is the video in question:https://www.youtube.com/watch?v=fw_I21RnBWg It made me wonder, do internal parasites have their own immune systems that do battle with ours? For example, would the same thing be happening to the Eosinophils when they enter the worms, being swarmed and attacked by the worms own immune system? submitted by /u/KameraadLenin [link] [comments] |
| How do tsunamis work and, more specifically, why wasn’t there a large tsunami after the earthquake off the Alaskan coast? Posted: 23 Jan 2018 04:08 PM PST |
| How do we fall asleep? Posted: 23 Jan 2018 02:32 PM PST Not why we fall asleep. I believe nobody knows the answer to that anyways? Most of the time we don't remember falling asleep. I ask because from time to time including last night I remain conscious while it happens and before I drift off I can choose to stay awake or not while my body is about to shutdown. It's weird when I think about it, but what exactly is going on? submitted by /u/real_shadowave [link] [comments] |
| Photons a massless particle with momentum? Posted: 23 Jan 2018 10:52 PM PST In not a physicist but it seems that to have momentum you would need mass. Anyone mind explaining this? submitted by /u/nessiehunt [link] [comments] |
| Why are milliampere hours commonly used instead of watt hours to measure battery capacity? Posted: 23 Jan 2018 08:01 AM PST When you're looking at the capacity of batteries, it generally gives you the capacity in mAh. I don't understand why though because without knowing the voltage, knowing the mAh tells you nothing about the batteries actual capacity. Wouldn't it make more sense to use watt hours instead of milliamperes when talking about batteries? That way you wouldn't need to then find the voltage and do the math to actually know the capacity. Is there some benefit to using mah that I'm not seeing? Also side question, why do companies always use milliampere hours instead of just amp hours. Wouldn't it just be easier to say for instance this phone has a 2.7 Ah, or this battery bank has a capacity of 30Ah rather than saying 2700mAh of 30000mAh? It seems like a horrible misuse of the metric system. I'd be like me saying I'm 1800 millimeters tall. Sure it's technically accurate, but it feels needlessly complicated. Edit: Fixed typo submitted by /u/RichHomieJake [link] [comments] |
| Black holes can expel jets of charged matter at relativistic speeds; do these jets provide thrust to the black hole? Posted: 23 Jan 2018 08:42 PM PST These 'astrophysical jets' are understood to be ionized matter. Should the incredibly powerful expulsion of this matter (thrown across thousands of parsecs at speeds up to .80c) not propel the expelling body in the opposite direction? Could not the supermassive black hole at the center of every galaxy be accelerating along the axis of the jet and dragging the galaxy with it? Are the galaxies all receding from us not due to expansion of space but because each galaxy has its own thrust? submitted by /u/Avalanche2500 [link] [comments] |
| What exactly does 100% Humidity mean? Posted: 23 Jan 2018 01:15 PM PST One of my old science teachers told me that 100% humidity means it is raining. I don't really understand, because a light drizzle will certainly be less humid than a heavy downpour. Was he wrong? Or does the humidity scale just stop at the point that rainfall occurs? submitted by /u/RebelEmpoleon [link] [comments] |
| Why isn't smoke hot? Posted: 23 Jan 2018 01:02 PM PST |
| Why will two balls shot into Newtons cradle release two other balls? (with energy and momentum conservation alone there are more options) Posted: 23 Jan 2018 02:09 PM PST If you shoot two balls into Newtons Cradle another two balls will be released at the other end. If none of the balls touch I understand this outcome. I noticed that if you glue the first two balls together you will have a different outcome: https://imgur.com/TqBuTXk But if the two balls touch, and are not glued, you would also expect a different outcome (harder for me to calculate). If you shoot one ball in and all the other balls touch you would also expect a complicated outcome (all the balls moving after collision (probably)). However this is not what you find experimentally... Can someone explain why Newtons cradle always acts like none of the balls touch. TO THE MODS: I know that previous posts about Newtons cradle have appeared on ask science, but they newer really approach the real question. The closest I got was this post: https://www.reddit.com/r/askscience/comments/7g5p31/what_determines_the_number_of_balls_being_knocked/ and especially this site: https://physics.stackexchange.com/questions/262998/experimental-data-for-asymmetric-newton-cradle However if you try to read it you will find that they use the "successive impact model". However the use of this model is what I am questioning (you would not expect this model to apply to a newtons cradle where the balls touch). No good answer exist on /r/asksience. submitted by /u/Luage [link] [comments] |
