So atmospheric CO2 levels just reached 410 ppm, first time in 3 million years it's been that high. What happened 3 million years ago? |
- So atmospheric CO2 levels just reached 410 ppm, first time in 3 million years it's been that high. What happened 3 million years ago?
- Why can't I use lenses to make something hotter than the source itself?
- If E=mc^2, my total energy is constant as my mass is constant. If I gain potential energy because I went up an elevator, my energy level changes but my mass is constant. What gives?
- Why do muscle cramps hurt?
- I fill the bottom of a bottle cap with my blood and let it dry overnight. Then I put the dried disc in a cup of water. the color leaves the disc and seeps into the water. I'm left with a translucent, slimy material. What is it?
- Why does water tend to follow the path of a nearby object instead of going straight down?
- What happens with degenerate wave functions in an atom?
- My textbook says "a complete explanation of why entropy increases with increasing molar mass is beyond the scope of this book." Could someone explain to me why?
- How do electrons "jump" to different energy levels without existing in-between the levels?
- Why do the noble gasses have such a small gap between their melting and boiling points compared to other elements?
- Why did scientists in the '60's think that Mars was covered in vegetation?
- How deep are the atmospheres of the Jovian planets?
- [Medical] How do they treat patients that are infectious enough to be dangerous?
- The Fukang meteorite is estimated to be 4.5 billion years old, how is it that people manage to estimate its age?
- If you had a large spherical radioactive sample, how much radiation would reach the surface?
- How is it that the concept of an Electromagnetic Field avoids the problems caused by the concept of a "Luminiferous aether" with regards to relativity?
- A year has Pi*10^7 seconds, where is the connection?
- What makes mercury and gallium liquids at room temperature when elements around them on the periodic table are solids?
- How do bots bypass captcha?
- Science or scam? "13 year old builds FREE energy device for under $15!"
- When we substract two natural numbers we get integers, when we divide two integers we get rationals, when we take roots of a positive rational we get reals, of a negative one we get complex. What is the next step?
- Will internal combustion engines ever reach a point where they emit zero carbon dioxide?
- Why the information paradox defies unitarity?
- By treating genetically transferrable conditions, are physicians effectively allowing the passing-on of them, and possibly even lowering life expectancy long-term?
| Posted: 24 Apr 2017 06:35 AM PDT what happened 3 million years ago to cause CO2 levels to be higher than they are today? https://www.scientificamerican.com/article/we-just-breached-the-410-ppm-threshold-for-co2/ [link] [comments]  |
| Why can't I use lenses to make something hotter than the source itself? Posted: 25 Apr 2017 04:33 AM PDT I was reading What If? from xkcd when I stumbled on this. It says it is impossible to burn something using moonlight because the source (Moon) is not hot enough to start a fire. Why? [link] [comments]  |
| Posted: 25 Apr 2017 06:29 AM PDT It seems like there's a discrepancy. Does E=mc2 not represent your total energy? [link] [comments]  |
| Posted: 24 Apr 2017 02:04 PM PDT I understand that muscle cramps are involuntary contractions of the muscle, but when our muscles contract voluntarily, it doesn't hurt. What about an involuntary contraction causes pain? [link] [comments]  |
| Posted: 24 Apr 2017 05:23 PM PDT |
| Why does water tend to follow the path of a nearby object instead of going straight down? Posted: 24 Apr 2017 07:41 PM PDT For example, when pouring water from a mostly-full glass, it will cause the water to follow the side of the glass instead of fall perfectly down. Also, a sink will do the same to your arm, or finger. [link] [comments]  |
| What happens with degenerate wave functions in an atom? Posted: 25 Apr 2017 07:36 AM PDT If a linear combination of some wave function that satisfies the Schrodinger equation for a given situation (for example, the electron in a hydrogen atom) also solves it, then there are multiple wavefunctions to describe one state. What happens to the electron with regards to this? What wavefunction does it assume? Does it matter? Thanks! [link] [comments]  |
| Posted: 24 Apr 2017 11:40 PM PDT I'm learning general chemistry and currently on entropy. I thought a simple way of explaining it would be because atoms with higher molar mass have more subatomic particles within them which leads to more possible microstates. Instead my textbook says "the energy states associated with the motion of heavy atoms are more closely spaced than thsoe of lighter atoms. The more closely spaced energy states allow for greater dispersal of energy at a given temperature and therefore greater entropy." I do not completely understand what they mean by that explanation. What is the full reasoning behind why my textbook implies that it is much more complicated? [link] [comments]  |
| How do electrons "jump" to different energy levels without existing in-between the levels? Posted: 24 Apr 2017 06:58 PM PDT |
| Posted: 24 Apr 2017 07:06 PM PDT |
| Why did scientists in the '60's think that Mars was covered in vegetation? Posted: 24 Apr 2017 10:53 AM PDT Text from an article in Science Digest in 1963
And then later in the article:
Full article here: http://imgur.com/a/Td5fK What changed in our knowledge of Mars over the years that these scientists were wrong about? [link] [comments]  |
| How deep are the atmospheres of the Jovian planets? Posted: 24 Apr 2017 02:01 PM PDT In gas giants, how deep do their atmospheres go? I understand that Jupiter will likely have a different atmospheric depth than say Uranus, so maybe it would be easier to express the values as a percentage of the radius of the planet. Additionally, what (if anything) would we find at their cores? [link] [comments]  |
| [Medical] How do they treat patients that are infectious enough to be dangerous? Posted: 24 Apr 2017 01:47 PM PDT Someone posted a while ago about seeing a biohazard room at a hospital where there were no visitors allowed and the doctors had to wear scrubs. It got me thinking- if a patient was sufficiently contagious, how would the doctors deal with it? How would they clean the room afterwards? If the patient died, what would they do with the presumably still dangerous corpse? [link] [comments]  |
| Posted: 25 Apr 2017 03:07 AM PDT I just wonder how it's even possible to date something to be that old, and based on what evidence would someone give it that estimate? EDIT: Added link [link] [comments]  |
| If you had a large spherical radioactive sample, how much radiation would reach the surface? Posted: 24 Apr 2017 02:28 PM PDT Suppose you have a spherical sample with total activity of A0 decays/second, and an "activity-density" of A0/(4/3piR3). Further assume the direction of the radiation is uniformly distributed. Each photon released has a probability of e-x*u of reaching the surface due to Beer's law, where x is the distance the photon travels through the sphere. Since the sphere will absorb a significant portion of the radiation, the radiation emitted out of the sphere should be a lot less than the activity of the sample would suggest. Is there any analytical way of determining this, or must it be done numerically? [link] [comments]  |
| Posted: 24 Apr 2017 09:44 AM PDT When people talk about a "field that permeates all of space" I picture something either like a 3 dimensional grid, or like a liquid that fills up the universe. However, it seems that something like that would create a universal frame of reference with regards to the propagation of light, which the theory of relativity states does not exist. What's a better way to conceptualize a field to avoid this problem? (I apologize if this question makes no sense, I don't really understand this stuff at all) [link] [comments]  |
| A year has Pi*10^7 seconds, where is the connection? Posted: 25 Apr 2017 01:03 AM PDT My mind got blown by this fact today .. but I can't see the connection between a year (orbit around the sun) and the number Pi*107. Can you help me? :) [link] [comments]  |
| Posted: 24 Apr 2017 11:03 AM PDT |
| Posted: 24 Apr 2017 06:07 PM PDT |
| Science or scam? "13 year old builds FREE energy device for under $15!" Posted: 25 Apr 2017 05:46 AM PDT If you google "13 year old free energy", you'll get about a bunch of news outlets reporting on this kid. Immediately red flags went up. We all know energy has to come from somewhere. There was a user a while ago that debunks this kind of thing. If anyone knows who they are and can tag them, that would be super. The news video claims " imagine this scaled up 20x." Currently, the kid is powering some LEDs with his device. If this is legit, I doubt it's going to scale appreciably. So, who wants to help figure this thing out? YouTube Link to video in question. [link] [comments]  |
| Posted: 24 Apr 2017 11:32 PM PDT |
| Will internal combustion engines ever reach a point where they emit zero carbon dioxide? Posted: 24 Apr 2017 10:12 PM PDT Will internal combustion engines ever reach a point where they emit zero carbon dioxide? Is this even achievable? I say 'near' because the mining and refining of oil and gas isn't carbon neutral and probably won't ever be. Although I am aware of projects like the Shell Quest Carbon Capture project, that are aiming to sequester carbon in the earth rather than the atmosphere, I am still doubtful of ever achieving this. As a huge supporter of renewable energy and the growth in that field, I'm trying not to suffer from my own confirmation bias online and in the media... it's beginning to look like we are reaching a turning point for this technology that could be great for this planet. BUT..My gut feeling tells me that the most profitable companies in the world are oil and gas related, and will do anything to maintain the status quo. On top of that the U.S and the world in general is heavily invested in O&G, and has built infrastructure to transport it everywhere - that and the recent technological innovations in extraction have the potential to create an environment where Oil stays cheap. If it's cheap, it will prolong the adoption of greener energy. Anyways - this question has been on my mind for a few months now and I'm wondering if this is even possible. Will we ever have ICE's that are carbon neutral? Not sure what flair I should use, should his be under chemistry? Thanks!! [link] [comments]  |
| Why the information paradox defies unitarity? Posted: 24 Apr 2017 02:43 PM PDT I am trying to understand the information paradox. Consider a wave function of two entangled particles, and one of them falls into a blackhole and reaches the singularity, since nothing is well defined there at that point the wave function looses information without having been collapsed, so far so good in term of understanding. This implies that unitarity is not conserved, and this is the part that I don't understand. Unitarity is the principle that the integral of the magnitude of the wave function in all space must be equal to one, and from that it follows that any operator times it's complex conjugate must be the Identity matrix, and I understand that (I can prove it), but I don't understand how nor why falling into the black whole and loosing information violates unitarity. Why can't there be a "black hole operator" which is unitary and that represents the changes made to the wave function?. If Unitarity is not preserved then, is it by being bigger or smaller than 1?, if it is smaller, does this mean that there is a chance of nothing happening?, if it is bigger, does that mean that something will definitely happen?, I can't really get my head around probabilities greater than 1. Thanks a lot [link] [comments]  |
| Posted: 24 Apr 2017 09:08 AM PDT If so, why is life expectancy still on the rise? What are the ethical arguments for/against this? (i.e. survival of the fittest) [link] [comments]  |
| You are subscribed to email updates from AskScience: Got Questions? Get Answers.. To stop receiving these emails, you may unsubscribe now. | Email delivery powered by Google |
| Google Inc., 1600 Amphitheatre Parkway, Mountain View, CA 94043, United States | |
