What happens when you sleep that makes you feel rested upon waking up? |
- What happens when you sleep that makes you feel rested upon waking up?
- How does a rocket propel in space?
- Does anti-matter have to react /annihilate with its exact counterpart? Like anti-hydrogen with hydrogen, not anti-hydrogen with helium, for example.
- [Physics] Do stars have a North pole and South pole like Earth?
- Can you help me understand diffusion?
- What exactly is The Drude Model for calculating metallic permittivities, and what exactly is metallic permittivities?
- How was speed of light measured accurately in the olden days when technology was archaic?
- How does the treasury department determine appropriate debt maturity distributions?
- Are laser microphones limited in frequency? Or could you use a maser or RF to achieve the same result?
- How does a nuclear bomb work? How is the explosion controlled and keep from splitting every single atom in the universe if it’s just a chain reaction of atoms splitting ?
- Why is it that portable chargers above a certain mAh cannot be brought on the plane?
- How are modern scales able to measure our body fat % when we just stand on them?
- If two fermions with the same spin can't occupy the same position, how 'close' can they be?
- Have there been any studies on the relationship between gender birth order and romance/sexuality later in life?
- How do 95% confidence intervals work in nutritional studies?
- Are laser weapons simply beyond our grasp for the time being or impossible/impractical compared to 'conventional' weapons?
- Why do they collect blood from mice’s orbital sinuses?
- Why does the Atlantic seem to have so few islands?
- Why is the Moon always in the night sky? Shouldn't it be on the "day" side of the Earth at some point every month?
| What happens when you sleep that makes you feel rested upon waking up? Posted: 18 Jul 2018 08:00 PM PDT |
| How does a rocket propel in space? Posted: 19 Jul 2018 12:53 AM PDT How does a rocket propel in space? I know that today they use ion thrusters or they shoot fuel out the back to accelerate in space but I don't get how that's possible. From what I understand, space tries to "suck" everything from the spacecraft so if that space craft ejects fuel, wouldn't the fuel be "sucked" from every direction once it exits the tail, therefore not providing an efficient thrust? The videos that explain this show that the fuel travels In a straight line directly opposite from the direction the spacecraft is going. [link] [comments]  |
| Posted: 19 Jul 2018 04:56 AM PDT I'm conscious making, containing and mixing this stuff is darn complicated but theoretically, would anti-hydrogen 'annihilate' with other nuclei? [link] [comments]  |
| [Physics] Do stars have a North pole and South pole like Earth? Posted: 19 Jul 2018 06:00 AM PDT |
| Can you help me understand diffusion? Posted: 19 Jul 2018 03:51 AM PDT imagine a closed system of indistinguishable, physically, chemically, characteristically identical atoms. imagine you could magically label them such that their characteristics wouldn't change, they would still be identical, but the labels could distinguish them. - if you took the right half of the system and labeled those atoms "A" and the left half "B," would they diffuse such that they were equally mixed? if so, if you then took half of the equally diffuse mixture and labeled them "C" and the opposite half "D," would C's and D's diffuse as well? if so, would they diffuse without interrupting the equilibrium of A and B? would there be equilibrium with respect to A, B, C, and D as well as AC, AD, BC, and BD? if so, and you did it again with half "E" and half "F," would equilibrium be reached with respect to all possible label combinations? - - I've heard it explained that diffusion is a statistical phenomenon rather than a physical one, that things in an area of high concentration have a higher probability to leave than they do to enter, since there are more things that can leave than there are that can enter. is it this simple? is there a better explanation? for some reason it hasn't ever clicked in my head. [link] [comments]  |
| Posted: 19 Jul 2018 04:39 AM PDT I know this isn't a well formulated question, but I'm taking a relatively deep plunge into physics for a job (plasmonics), and it'd be really helpful. What exactly does this Drude Model do, and what can it be used to find about a specific metal? I'm assuming this metallic permittivity has something to do with the plasmon frequency of the metal (to my understanding, that's the frequency of an electromagnetic field that will excite the free electrons in the metal the most). [link] [comments]  |
| How was speed of light measured accurately in the olden days when technology was archaic? Posted: 18 Jul 2018 07:26 PM PDT Especially that light can supposedly travel the earth 7 times in one second or something ridiculous like that. [link] [comments]  |
| How does the treasury department determine appropriate debt maturity distributions? Posted: 18 Jul 2018 07:02 PM PDT With a lot of investors concerned with the possible inversion of the yield curve, I was curious about how likely/possible it is for the Treasury Department to shift their auction amounts to higher duration notes/bonds and away from shorter bills/notes to steepen the yield curve.
I've found that average length has been increasing for a few years, and the Office of Debt Management has a plan for future debt schedules (page 27/29), but a lot of their explanations for their maturity schedule centers around vague terms like "Maintaining Liquidity".
So, basically, what are the general factors that the treasury department considers when they create they determine maturity schedules and do they factor in monetary policy/federal reserve actions?
Thanks [link] [comments]  |
| Posted: 19 Jul 2018 02:10 AM PDT |
| Posted: 18 Jul 2018 06:27 PM PDT |
| Why is it that portable chargers above a certain mAh cannot be brought on the plane? Posted: 18 Jul 2018 07:16 PM PDT I was on a plane lately and they took away my 50000 mAh power bank :( [link] [comments]  |
| How are modern scales able to measure our body fat % when we just stand on them? Posted: 19 Jul 2018 12:12 AM PDT |
| If two fermions with the same spin can't occupy the same position, how 'close' can they be? Posted: 18 Jul 2018 06:00 PM PDT I'm almost certain I'm not grasping even the basics here, but does 'position' in this sense mean the same spot in space, or space-time? Or is this some other meaning of position that isn't quite like the colloquial use? [link] [comments]  |
| Posted: 18 Jul 2018 05:34 PM PDT My wife is the youngest of 4 and the only girl. We now have a daughter and a son, the daughter is 4 years old than the son. She was noticing how different things seem to be for our son than when she was young. There's a stronger baseline of girl toys and shows, and more of a general understanding of women's needs than she ever experienced. We know in general homosexuality is a mix of genetic and environmental factors, and were curious if growing up with an older sister raises those odds (we don't care personally, we're just curious scientifically). We're also curious if marriage/divorce rates differ as we're aware our son is more comfortable with girls than other boys his age, which we think is because he lives with an older one. So, we're just curious if there's any work that has been done on correlations amongst these things. Thanks in advance. [link] [comments]  |
| How do 95% confidence intervals work in nutritional studies? Posted: 18 Jul 2018 05:26 PM PDT This study looked at protein requirements for female cyclists: https://www.ncbi.nlm.nih.gov/pubmed/24476478 The mean protein requirement was 1.6g/kg, but one woman required 2.8g/kg to reach nitrogen balance, a huge disparity. The authors reported that the upper end of the 95% confidence limit was 2.2g/kg, and suggested it as a guideline. So in this case, are they saying that 95% of all women studied had their protein requirements met by 2.2 g/kg, and that the woman requiring 2.8 g/kg was an outlier in the highest 5%? [link] [comments]  |
| Posted: 18 Jul 2018 11:48 PM PDT Say I want to make a laser cannon to blow up tanks, is the technology to do so cheaply and effectively compared to a rocket launcher simply not there yet or at least theoretically possible or is it impossible to do so practically? I read this forum post that seems to make it sound like lasers are really impractical in terms of energy efficency and certain materials like metal are apparently not good receptors of light energy. So are lasers just a thing that science fiction jumped the gun on or is there a future yet that might hold blasters? [link] [comments]  |
| Why do they collect blood from mice’s orbital sinuses? Posted: 18 Jul 2018 12:30 PM PDT (Tagged as bio because I'm not sure what else.) So I'm volunteering at a lab this summer as part of a student training program. It's been super cool, but there's one thing I cannot get out of my head: why do they take blood from the eyes of the mice? I was watching them take blood samples today, and not going to lie, it's kind of... icky. Not going-to-pass-out-right-here-in-the-lab icky, but ickier than anticipated. What they were doing was anesthetizing the mice, then jamming a teeny capillary tube right near their eyeballs and drawing blood with it. (Most of my fellow volunteers were not fans of this.) It would bleed afterwards, usually just a drop, but one or two mice bled quite a bit onto the table. The mice would wake up a few minutes later and go about their day, in no apparent discomfort, but it got me wondering. Why exactly do they use this method of collecting blood? (As far as I know, the study they're doing isn't specific to the eyes.) The procedure itself is fast, but it requires individually anesthetizing every mouse, which slows things down a lot. The mice seem fine afterwards (as far as I can tell; I'm not a professional but they act exactly the same as they did before), but would they also have been fine with some other method? Is there something about mice in particular that makes this spot a really good spot for collecting blood? I've tried Googling it, but most of the results are just instructions on how to do it and not why they're doing it (that or animal welfare/ethics groups, which have plenty of legitimate concerns, but that's not really what I was looking for.) [link] [comments]  |
| Why does the Atlantic seem to have so few islands? Posted: 18 Jul 2018 08:09 AM PDT |
| Posted: 18 Jul 2018 08:04 PM PDT Anecdotally, it seems that the Moon always occupies a spot on the night sky regardless of where you are on Earth. Even during a new moon, the Moon still occupies a spot in the sky despite being invisible. I know the Moon's orbital plane isn't perfectly perpendicular to the Earth's axis of rotation but shouldn't there still be a good chunk of the month where the Moon is on the "day" side of the celestial sphere and thus completely gone from the night sky? [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, 1600 Amphitheatre Parkway, Mountain View, CA 94043, United States | |
