title list | over_18 list | post_content stringlengths 0 9.37k ⌀ | C1 list | C2 list | C3 list |
|---|---|---|---|---|---|
[
"How do you calculate the velocity of an electron relative to the nucleus?"
] | [
false
] | null | [
"It depends on how you define its velocity. Classical mechanics doesn't work for atoms, you need quantum mechanics. You can define a velocity operator in terms of the momentum operator:",
" = ",
"/m.",
"We're interested in energy eigenstates of an atom, which are not eigenstates of this operator. So electrons... | [
"Also the physical reason for the value of <v> to be zero is simply because the electron is just as likely to be moving towards the nucleus as away from it."
] | [
"Or, an alternative way to look at it is that <v> is the velocity of the centre of mass of the electron distribution. For a stationary bound state, this centre of mass must be centred on the atom, so <v> relative to the atom must be 0. Of course there can be non-stationary excitations in which the centre of mass os... |
[
"Do radio waves have a practical lower limit on their frequencies?"
] | [
false
] | To the best of my knowledge, radio waves have the longest wavelength and lowest frequency of any classification on the electromagnetic spectrum. Is there a reason we do not broadcast at incredibly low frequencies? A quick search claimed that longwave radio doesn't go much lower than about 150 kHz. Is there a reason we ... | [
"Ultra and extremely low frequency radio waves have been used to communicate with submarines, and through the ground. Very large antennas are required to trasmit at such low frequencies, and the bandwidth is very limited. "
] | [
"Just to expand a little on ",
"ELF",
", the lower limit of that band is 3 Hz and anything lower seems to be considered noise rather than a usable radio signal. ",
"Also, to put things in a little perspective, the ",
"submarine communications system",
" mentioned before operated at 76 or 82 Hz, transmitt... | [
"you want your antenna to be at least quarter of the wavelength of the signal. you can do the math to determine the wavelength of any frequency wave because they are inversely proportional by the speed of light. for example the lowest frequency am stations are about 500 khz. c / 500khz = 600 m. 1/4 of that is 150 m... |
[
"There's a topic on AskReddit posted by someone with a blood type that can't be identified. What causes this to happen?"
] | [
false
] | [deleted] | [
"ABO are the major groups, but there are also subtypes such as A1, A1B, A2, A2B, etc. They differ due to the number of antigen sites expressed. ",
"This can confound a typical blood test by producing a mixed-field pattern of small agglutinates."
] | [
"Homeopathy. It's all based on a book by one naturopathic doctor."
] | [
"yeah figured, their website is pretty convincing though, its blue and white and everything which is pretty medical."
] |
[
"Do different muscle groups have to compete for recovery?"
] | [
false
] | I've read that you can only gain about 2 pounds of muscle a month, so my question is how does the body know where to distribute this gain? Does it compensate for the muscle groups worked more frequently/intensely? What if someone were to only train one muscle group? Would you still be able to reach the 2 pounds of musc... | [
"Short answer: no, they don't compete. More intensely worked muscle grows faster than less-intensely worked muscle.",
"Long answer:",
"The myofibrillar proteins that give muscles their strength are synthesized inside the muscle cells themselves. And muscle cells are notoriously slow to synthesize proteins, comp... | [
"It actually differs for different people, and seems to have a genetic basis. Some people's muscles respond much more aggressively to exercise than others...where one person gains 1 pound of muscle a month with regular workouts, good diet and rest, another person doing the exact same workout might gain 2 or even 2.... | [
"That's very interesting and informative, thank you for your answer. If I'm understanding correctly, most of the muscle repair and growth is done within 24-48 hours. But since the overall cellular growth is so infinitesimal, it would take months of actively training the entire body to produce significant muscular g... |
[
"What are MicroRNA Biomarkers?"
] | [
false
] | According to the about the Colorado movie theater shooting, the gunman was once a PhD student in neuroscience. In the 10:46am update, integ3r writers the gunman was scheduled to give a presentation on "MicroRNA Biomarkers." What are they? How do they fit into the study of neuroscience in general? Is there any controver... | [
"First let's talk about microRNAs (miRNAs). These are short sequences of RNA (about 1-5% the size of a normal RNA sequence) coded by our genomes that are generally responsible for regulating the amount of a certain protein that gets made at the level of RNA. In other words, miRNAs prevent their RNA targets from bei... | [
"I'm sure there are many applications. Alzheimer's disease biomarkers seems most likely, but really I wouldn't be surprised by any application. miRNA research is becoming very widespread."
] | [
"XIllusions did a great job explaining miRNAs, but I just want to clarify, before the newsmedia turn it into a meme, that \"miRNA biomarkers\" isn't really jargon that I recognize - it just means biomarkers (something you can measure to diagnose/prognose a disease) that happen to involve miRNAs. There are lots of m... |
[
"Science, I wanted to know what the damage and effect on human life would be if the same solar storm that hit in 1859 were to hit today."
] | [
false
] | I'm wanting to find out what would happen if the so-called "Perfect Solar Storm of 1859" hit today, would all electronics and technology in-whole basically burn-out sending us into the dark ages? What would happen with our technology? Is earth prepared for such a hit again? The year of 2012 is supposed to be a year of ... | [
"There was a lesser, but still significant, geomagnetic storm in 1989: ",
"http://en.wikipedia.org/wiki/March_1989_geomagnetic_storm",
"In terms of wiping out all electronics, it would take a far, far larger storm than the one in 1859 to short literally ",
" with a circuit in it. Your watch would probably sti... | [
"The US still manufactures large power transformers, for instance ",
"Waukesha Electric Systems",
" does. I used to work there testing their large power transformers. Every single one of these transformers were sold with surge arresters to help protect against scenarios like the one stated above. "
] | [
"A full evaluation of this event has been done. See: ",
"http://www.nap.edu/catalog.php?record_id=12507",
". You can download the book for free in PDF form. It's titled \"Severe Space Weather Events\", and was the result of a workshop in 2008.",
"Also see: ",
"http://science.nasa.gov/science-news/science-at... |
[
"Can hydrogen cations be used to power electronics similarly to electrons?"
] | [
false
] | In the way we jump electrons through wire, could we somehow do the same with protons as a means of power? | [
"While what mirozi says is completely correct, we cannot move protons through metals, I'm going to entertain the idea that we could make any hypothetical electronics (not constrained by wires made of metal). ",
"If we could create tubes with a magnetic field small enough to fit inside our electronics (or shall we... | [
"Electrical current is a flow of charge, not electrons. You could in principle transfer electrical power by firing a beam of protons through a vacuum. There's just no practical reason to do so."
] | [
"Ofcourse not. ",
"Electrons are moving through the wire, because they are electrons, not because they have small charge. And they are moving because it's property of metal, there is cloud of easy to move electrons. ",
"Second thing - proton is huge in comparison with electron. "
] |
[
"Why is it when I close one eye, the vision in my open one appears to have \"Warm\" colors, and the other appears to have \"Cool\" colors?"
] | [
false
] | For example, when I close my left eye, everything I see through my right eye has an orange-tint to it, seeming like all the colors I see are "warm". However, when I look through my left eye with my right eye closed, there is a blue-tint to all the colors I see, making them appear "cool". Is this so all the colors I see... | [
"My photography expertise is usable here! ",
"So see this. When you close an eyelid, the sunlight is filtering trough a blood lined flap of skin. This makes the \"warm\"(sub 4300kelvin\" light look even warmer. ",
"See, our eyes adjust the \"white balance\" of our surroundings. That's why when you walk into a r... | [
"It is actually a chemical change that occurs in the cone cells of the retina. The cells adjust to the amount of light by activating or deactivating certain photochemical pathways. When you go from bright light to dark, your iris adjusts in seconds to let in more light, but the chemical change in your retina takes ... | [
"Sometimes your eyes have different ratios of the color sensing cone cells. There are even people called unilateral dichromats who are colorblind in one eye but see normally in the other (not to say that is what you seem to be describing)."
] |
[
"What happens if you ingest cancer cells from food?"
] | [
false
] | Can a person digest cancer cells? Does that cancer affect them? If there's no affect in animal meat ingestion, what about in cannibalistic scenario? | [
"Aside from being melted by stomach acid, there is generally enough genetic difference between two people for another person's cells to be targeted and destroyed by the immune system. Unlike when your own cells go rogue and become cancerous. It's the same reason why people's immune systems can reject transplanted o... | [
"Can cancer be transmitted through virus? ",
"Usually some cancers are caused by a virus but not transmitted by them. The virus only contains DNA or RNA that encodes the virus itself and not DNA from the host cell."
] | [
"The virus only contains the instructions for the virus itself to replicate, but it can be a trigger for the host cell to mutate into cancer? Is this correct?"
] |
[
"If the stars in the sky suddenly appeared exactly where they are actually located today (instead of appearing as they do now, where they were when light left them), which constellations would change the most? What other interesting changes would we see?"
] | [
false
] | null | [
"There's a star in our galaxy (precisely in the Orion constellation) called ",
"Betelgeuse",
".",
"Why is Betelgeuse interesting? It's a red giant. A red giant about to go supernova. \nOr rather, a red giant that ",
" on the verge to go supernova. ",
"So were we to have a snapshot of how Betelgeuse looks ... | [
"Then that's a very sad set of circumstances, but still very exciting academically. ",
"I mean, it's not like we could do anything about it. We couldn't save black rhinoceros, and they were in our back yard. ",
"But! Betelgeuse going supernova would be really exciting! We'd learn so much from having the ability... | [
"I love to tell people about betelgeuse, so they'll look up at the sky hopeful, then disappointed every night. (Although, when it goes, we'll see it during the day!) "
] |
[
"How does Saturn's moon Titan have oil? Was there life?"
] | [
false
] | So they discovered oil on Titan. My question is how was the oil formed there? On earth it was formed because of plant and animal matter decaying? What process is at work for Titan? | [
"Titan has hydrocarbons which are found in petroleum but they have a different origin in that they are abiogenesis - that is created without life. Instead Titan formed with a large complement of methane which us sensitive to UV light from the Sun. Over millions of years, methane molecules have one or more hydrogen ... | [
"No, organic in this context is \"",
"organic compound",
"\". It means it has carbon in it."
] | [
"No, organic in this context is \"",
"organic compound",
"\". It means it has carbon in it."
] |
[
"What's the clearest distinction you can give of a psychopath vs a sociopath?"
] | [
false
] | null | [
"This is a question of usage rather than one of fact, and not one with a really solid answer. The ICD-10 and DSM-V, the two main sources of definitions for medical/psychiatric billing, don't draw a distinction. Both refer instead to \"antisocial personality disorder.\" ",
"Looking elsewhere, one source uses socio... | [
"What I arrived at myself was also fairly inconclusive. What I found repeatedly though was - Psychopaths generally more: Violent, Charming, Aware, Organized, Biological condition, No moral compass. Sociopath: Delusional, Impulsive, Environmental condition, Damaged moral compass. ",
"I also noted the psychosis and... | [
"The DSM specifically states that the diagnosis of ",
" replaces what was referred to as psychopathy or sociopathy at different points in time.",
"The research literature still discusses psychopathic traits, but there is no diagnosis that will result in someone being labelled a psychopath or sociopath. But, for... |
[
"Pond algae has taken over and I need some serious help!"
] | [
false
] | null | [
"I dont know if this is the type of algae that you have in your pond...but these resources might help.",
"Harmful Algal Bloom Response Strategy for Recreational Waters"
] | [
"http://imgur.com/a/Bgark",
"Here is a link to some pictures. I'm kinda new here so sorry if this isn't the correct way to post."
] | [
"I dont know anything about algae, and try ",
"/r/askreddit",
". It is the more appropriate place for questions like this. "
] |
[
"If someone did manage to build Jurassic Park, would the dinosaurs be almost immediately killed by bacteria or viruses that had tens of millions of years of evolutionary advantage on them?"
] | [
false
] | I know that recent discoveries on the short halflife of DNA put raptors chasing Jeff Goldblum beyond our reach for other reasons, but would this do it too? Could dinosaur immune systems fight off modern pathogens? | [
"Yes! Thanks for humouring me :p (fairly new to Reddit, not sure what the protocol is for digressing hugely in a thread, if someone tells me I'll follow it).",
"Hokay so, Influenza is a virus. This means it is a small capsule filled with a very small amount of RNA. RNA is basically the blueprint used to create pr... | [
"Yes! Thanks for humouring me :p (fairly new to Reddit, not sure what the protocol is for digressing hugely in a thread, if someone tells me I'll follow it).",
"Hokay so, Influenza is a virus. This means it is a small capsule filled with a very small amount of RNA. RNA is basically the blueprint used to create pr... | [
"I would suspect that they would be fine. Evolution is not normally a case of continually getting better but of adapting to the current environment. The current pathogens are adjusted to attack organisms alive at the moment. I would imagine the immune systems and general physiology of dinosaurs would be sufficientl... |
[
"Is skipping more efficient than running or walking?"
] | [
false
] | What is the most efficient way for the human body to transport itself without using any artificial enhancements? | [
"It appears that skipping is more energetically expensive, at least according to this paper ",
"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1689187/pdf/9699315.pdf"
] | [
"check out figure two in that paper - the work is higher, but the \"apparent efficiency\" is actually about the same as walking! that's because there's actually some elastic recovery (see energy recover, 5th graph). walking is still better -- but not by as much as we would expect :)"
] | [
"Running and skipping are less efficient than walking because the added acceleration necessary to get both feet off the ground does not help in getting from point A to point B. In a sufficiently low friction environment, sliding becomes preferable to walking for the same reason (don't want to lift legs unnecessaril... |
[
"Does the pupil shape of specific animals (goats; rectangular, cats; oval) affect the way they create an image in their mind?"
] | [
false
] | null | [
"We know it affects the way they perceive the world (vertical pupils are better at pinpointing one target, horizontal ones give a wider field of view), but it's kind of hard to see whether the animals' subjective experience is affected. After all, we can hardly ask them to describe the way they perceive the world."... | [
"Because of the amount of interpretation the brain has to do to parse the signals from the optic nerve into a coherent image, most of what we can do in that regard is limited to identifying the strengths/limitations of that particular animal's vision, as opposed to being able to generate a concrete image of what th... | [
"What if we make a camera with an aperture in those shapes, and we analyze the images they make? Wouldnt it be representative of how they see? "
] |
[
"How do you explain evolutionary theory, especially transitional fossils and organ development, to an ardent science denier and creationist?"
] | [
false
] | null | [
"You should be able to copy and paste, but you can't just transfer."
] | [
"Such open-ended questions are better suited for our new-ish sister sub ",
"/r/asksciencediscussion",
". Please consider reposting there instead."
] | [
"Do I have to rewrite it, or is there an easy way to transfer it?"
] |
[
"How are babies born with heroin (or any drug) addiction medically treated? And what are their symptoms that lead to the diagnosis?"
] | [
false
] | null | [
"This is called Neonatal Abstinence Syndrome. Generally, treatment is based on the drug in question and the severity of symptoms. In most cases the child is simply calmed and allowed to run through the withdrawal period, while supervised medically. For more potent drugs such as heroin and similar, dosage of methado... | [
"Actually, where I live long term hospitalization is not a thing. Babies are sent home on methadone or naloxone weans, with home health monitoring. By the way, there has been a 400% increase in these situations in my area in the past 3 years. :("
] | [
"Why give naloxone would that be the opposite idea as a taper or 'wean'?"
] |
[
"How does moisture affect the molecular structure of plastics like Nylon and PET specifically?"
] | [
false
] | I own a 3D printer, and have to keep my filament dry in order to print objects more successfully. "Wet" filament (filament that has absorbed a lot of moisture) tends to be more brittle in my experience, and dry filament seems to have more flexibility. I looked into why this was the case, and could only find answers aki... | [
"I don't think water reacts with PET or Nylon, so there's no \"molecular\" changes in the structure",
"Nylon and PETG do absorb water and water droplets/vapor is getting trapped in the polimer's structures. Your analogy with steel and carbon is quite accurate.",
"When you print with damp plastic at high temtera... | [
"Carbon in steel is also in a non-reacted state AFAIK. So it's trapped in the crystal structure and modifies it's properties, so the analogy is very correct. With the execption that carbon does not explode when heated and water in PET or Nylon does :-)"
] | [
"I appreciate your response! :)",
"It's good to know I was somewhere in the ballpark. I was sparked to ask the question by the fact that I was becoming able to tell if a roll was wet by bending the filament and seeing how brittle it was. If it was brittle, it was likely wet. That property reminded me of the relat... |
[
"Is there an upper limit for capsaicin “activation”?"
] | [
false
] | As my understanding goes, capsaicin activates the heat receptors in your mouth. Is there an upper limit of capsaicin concentration where all the receptors in your mouth are activated and no more capsaicin will produce any discernible difference in heat perception? (Tagged “Human Body”? Maybe?) | [
"the answer is yes; the why is quite amazing. so your neurons communicate with neurotransmitters, of which there are two kinds. ",
"there are ‘small molecule’ neurotransmitters like serotonin, dopamine, adrenaline, etc all of which are readily produced by enzymes in the cell and they are in abundance. ",
"the... | [
"How short is that short-term tolerance?\nIs the SP also involved in long-term developed tolerance?"
] | [
"Capsaicin indeed hits terminal threshold of the receptors and temporarily disables them.\nConsuming capsaicin regularly makes the receptors to adjust sensitivity and raise the terminal threshold.",
"Thats why chili eaters tend to increase dosage. \nHighest \"trained\" eaters can consume concentrations comparable... |
[
"When you gain a lot of weight do your nerves and veins grow to accommodate the expanded surface area of your body?"
] | [
false
] | When you lose weight do your nerves and veins shrink? Also, do thinner people have more skin sensitivity due to nerve endings being more concentrated in a smaller surface area? | [
"Pretty much \"no\" with regards to nerves. Let me try to explain - and by all means I encourage people to chime in if they can expand on this, I'm drawing on old knowledge here!",
"Your spinal cord branches out from your spine through the left and right gaps between your individual vertebrae. These are called ne... | [
"Cardiomegaly from obesity leads to enormous thin walled floppy hearts. Changes in athletes appear more like meaningful thickening of the heart walls with slightly increased size. Source: I recover hearts from dead people. ",
"Link to athletic heart information",
" versus ",
"obese heart",
". Probably bette... | [
"Cardiomegaly from obesity leads to enormous thin walled floppy hearts. Changes in athletes appear more like meaningful thickening of the heart walls with slightly increased size. Source: I recover hearts from dead people. ",
"Link to athletic heart information",
" versus ",
"obese heart",
". Probably bette... |
[
"Why is the sun yellow?"
] | [
false
] | I read earlier today that it emits light in the yellow, blue and, green wave length spectrum but the blue and green get absorbed by the atmosphere. If this is true wouldn't the sun look different in outer space? | [
"Just to add to that, here's a ",
"photo"
] | [
"Just to add to that, here's a ",
"photo"
] | [
"The sun only peaks in the yellow-green if:",
"If you look at actual data, sunlight ",
"peaks in the blue/violet",
".",
"Also, if you plot irradiance versus ",
", sunlight actually peaks in the infrared. ",
"Which peak is physically meaningful? Neither one. The peak of a broad spectrum does not mean muc... |
[
"Why is the single-strand nanopore DNA sequencing method so error prone?"
] | [
false
] | I just read that a relatively new method of DNA sequencing - passing single strands of DNA through a nanopore, without requiring Polymerase Chain Reaction (PCR) amplification - can do very long DNA reads, but also that it is very error prone compared to traditional methods. I also read that this method preserves epigen... | [
"The error rate comes from interpreting the signal which is measured and is not a feature of the length of the DNA. In pretty much all sequencing technologies the sequencing machine outputs a position or time dependent measurement. You need to interpret these measurements to work out which base is at which position... | [
"Pretty much.",
"Multiple reads are used for redundancy and base calling software can be quite sophisticated for data correction "
] | [
"I'm by no means an expert here but my understanding is that there isn't much point in making the chemistry or molecular process more accurate.",
"These nano scale processes are noisy, that's just a fact of working with such tiny systems that are beholden to all kinds of quantum scale and thermodynamic effects . ... |
[
"Heat Transfer"
] | [
false
] | I work in a refrigerated warehouse and have noticed that different materials do not all feel the same temperature. For example touching a steel pole feels incredibly colder then a cardboard box. So my question is could there be something you hold that is incredibly hot or cold that wouldn't damage your hand. | [
"It has to do with the rate that materials transfer heat.",
"This video explains it very well: ",
"http://www.youtube.com/watch?v=vqDbMEdLiCs",
"Let's look at the metal and cardboard example. They are both sitting in the same room, which is at a constant temperature, right? Therefore, they have to be the sa... | [
"What you are feeling is the change in temperature of your skin as heat moves from your warm hand into the cold object. Some objects conduct that heat out of your skin faster than others, so your skin temperature drops rapidly and your nerves go, 'Oh, that's cold!' Other objects don't conduct heat well, so even tho... | [
"What damages your hand is not the heat transfer, it's the rate of heat transfer. If your hand can dissipate heat at around the same rate as heat is transferred to it, it wouldn't damage you. "
] |
[
"How an Aerospike engine really works ?"
] | [
false
] | Hi all, I’m interested in all things rocket, and I found the Aerospike engine very interesting (and super cool looking) However, I can’t understand what makes it work correctly compared to a normal bell engine : -The bell shape is here to redirect the flow (that have a random distribution) so that its coming out on the... | [
"I don’t understand, why, in that case, the thrust isn’t expending on the side like a normal random flow firing in all direction ? the exhaust pressure is still much higher than air….. one side of the exhaust is on the spike make a “half” bell, right, the other, exposed to air, should just go in all directions, lik... | [
"So, would a theoretical single stage to orbit vehicle with Aerospikes still need a bell style engine in vacuum? Or does those wedge shaped multi Aerospikes I see animations of help with that? Also if the virtual bell expands in low pressure air reduces chamber pressure, does the Aerospike lose efficiency?"
] | [
"Chamber pressure refers to pressure in the combustion chamber, not in the bell, so that remains constant. ",
"Aerospikes do not lose much efficiency while the pressure drops, unlike bell engines designed to work at high pressures specifically, and that's actually the whole point of aerospikes. In fact, bell engi... |
[
"Is there a theoretical limit to the size of natural gemstones?"
] | [
false
] | The largest precious gemstones are pretty big but you could still hold them in your hands. There seem to be some very large rough jades around and absolutely massive quartz crystal formations. Could gemstones the size of cars and larger exist in the earth somewhere? | [
"In theory there's not a limit. Crystals form by adding unit cells to a crystal lattice- as long as the conditions are right you can keep adding more and more unit cells to whatever size you'd want. At some point you would run into problems with other material properties- like you could grow a crystal so large that... | [
"Crystals can grow for as long as they have the ingredients to do so (the right elements) and the appropriate conditions (the necessary pressure and temperature). It seems that at some point, the size of a crystal will be limited by the fact that part(s) of it will enter regions of the Earth where the pressure-temp... | [
"The pressure in the center of the gem would exceed the boiling point and become molten. ",
"Pressure does not create heat and actually has the opposite effect you’re thinking of here for phase changes. Increased pressures ",
" the melting point of a solid, all other things being equal. For example, the Earth’s... |
[
"What is the difference between the local and global speed of light?"
] | [
false
] | As explained you'll always measure the same value for locally, but globally it might be lower because of gravitational fields. What I'm wondering is at what distance do you consider something to be global rather than local? That might be a plain misunderstanding from my part, so alternatively, is it more correct that t... | [
"First you need to know how we define and measure relative velocity of two objects in pre-relativity physics. Our reference frame is fixed and there are two objects, each traveling on some path through space. The tangent vector to each path is the velocity of the respective object. The difference in the two velocit... | [
"That is absolutely 100% true. In relativity papers, you will often see things like \"locally Minkowskian\" or \"locally flat\" referring to just this fact."
] | [
"Is it then correct to say that GR is equivalent to SR over small enough patches of spacetime? By \"small enough\" I mean the case where the \"spacetime volume\" (not sure of the technical term for this) of the patch tends to 0."
] |
[
"When I take a multivitamin and my urine is bright yellow for the next few hours, have I derived any benefit?"
] | [
false
] | From some research, I believe the bright yellow color is from B6. So I suppose this question could be broken down into several subquestions: have I derived any benefit from the B6; are there other less obvious vitamins that are being excreted in my urine and I am deriving benefit from those; would it be just as useful... | [
"Vitamin supplementation for someone without vitamin deficiency likely won't provide you with much benefit beyond placebo effect. Our bodies will simply excrete excess vitamins. If you are ingesting so much B6 that you're seeing it in your urine, that just means your body is overloaded with B6 and is getting rid of... | [
"As a side note you can ingest large amount of water-soluble vitamines (B and C to generalize) because you can pee them out easily. Vitamins A, D, E, K are fat-soluble and can accumulate when taken in large and excessive amount leading to toxicities as seen in the link 1 of dorsalispedis' comment."
] | [
"Yes, thanks for this, I forgot to mention fat vs. water-soluble."
] |
[
"Where is the \"equal but opposite\" force where gravity is concerned?"
] | [
false
] | [deleted] | [
"Newton's Third Law implies that every object that is pulled towards another object, in return also pulls that other object towards itself. Similarly, anything that pushes against an object also has the object push back with equal force.",
"Now with gravity, the Earth pulls us towards it. But in return, each of u... | [
"I'd like to point out how minuscule that acceleration truly is. If you start 50 meters above Earth, and fall to it, the Earth is going to move up to meet you by less than the length of a quark."
] | [
"The force of gravity is a ",
" attraction between objects and the strength of that force is G",
"m2/r",
" where G is the universal gravitation constant (it tells us how strong gravity is in general), m1 and m2 are the masses of the two objects, and r is the distance between the centers of mass of each object... |
[
"[Physics] Smaller than Planck Length and Radiation?"
] | [
false
] | Is it possible to put enough energy into a particle so that it radiates radiation with a wavelength smaller than the Planck length? I've been taught that there is nothing "shorter" than the Planck length but also that there is no limit on the amount of energy a particle can have and that energy is proportional to a sho... | [
"Where were you taught there is nothing shorter than the Planck length?",
"Anyway, any given electromagnetic wave can have a wavelength shorter than the Planck length in the right reference frame. Something moving very very close to the speed of light relative to the emitting source could see that.",
"However, ... | [
"It is the Doppler effect."
] | [
"I've been taught that there is nothing \"shorter\" than the Planck length",
"FYI, this is not (necessarily) correct, and according to currently-accepted theories there is no reason to believe that things shorter than the Planck length cannot exist.",
"The Planck length may be the shortest possible ",
" lengt... |
[
"Why do plants provide us with such essential nutrients to live and be healthy? What's in it for them?"
] | [
false
] | [deleted] | [
"Profound question. They do need our carbon dioxide, but then we need their oxygen so respiration is a wash. We originate from the same ancestral prokaryote so maybe both animals and plants have the same basic nutrient needs - we just gave up the ridged cell wall of plants for mobility but lost the ability to manu... | [
"What on Earth does that have to do with what I just posted?"
] | [
"Let's put it another way. Lions can eat humans as meat. What do humans get out of that?",
"Nothing, just like the plants. It's just that sometimes, something that is beneficial for them is also beneficial for us. For example, they can grow fruits to attract insects to carry their seeds around. We, as clever litt... |
[
"Could gravity be the opposite force from what it is known to be today? Planets and stars are known to pull, but is it possible that they just pushing away the one from another?"
] | [
false
] | null | [
"'Physics'"
] | [
"'Physics'"
] | [
"Thank you for your submission! Unfortunately, your submission has been removed for the following reason(s):",
"/r/AskScience",
"For more information regarding this and similar issues, please see our ",
"guidelines",
"If you disagree with this decision, please send a ",
"message to the moderators."
] |
[
"How can different packets of information be sent through wires when all that goes through them is current?"
] | [
false
] | null | [
"Similarly, ask yourself how words and sentences can be sent through air when all that goes through it is vibration."
] | [
"Changes in voltage and current over time can be used to transmit information. \"Packets\" of information are interpretations of those changes using some agreed-upon encoding. Think of it like super advanced morse code where each sent \"character\" represent a sequence of bits. The presence or lack of a current ... | [
"To illucidate on what others have said, ",
"here is a picture of the sort of voltage waveforms that could appear on a wire",
" (The picture is from a measurement equipment manufacturer's website). Clearly the top and bottom signal could contain different information. There's a lot more to it than that, but tha... |
[
"If we send a submersible probe to Europa, how will it communicate with us?"
] | [
false
] | What kind of problem does the 10km+ thick ice sheet pose in sending information back to earth? What are some of the possible solutions to this problem? | [
"Ice behaves somewhat transparent, depending the frequency used. ",
"They use this to map underneath ice sheets.",
" - although the signal gets attenuated a lot so you have to do a lot of signal processing. ",
"But.. if our knowledge of Europa turns out to be true, that its a solid core with ocean covered wit... | [
"It would take years to design the probe and it would take years to get there, too. Melting through the ice is probably among the shorter things in the overall project.",
"What if the spot we land at just happens to be 50km thick with ice.",
"That's why you explore the potential landing site before.",
"We hav... | [
"Jupiter has an incredibly strong magnetosphere that traps highly energetic charged particles from solar winds. Similar to the Earth's Van Allen belts, the charged particles accumulate in belts of radiation around Jupiter, only thousands of times more energetic."
] |
[
"Does Bell's inequality only apply to entangled particles? Could radioactive decay still have hidden variables? (More in comments)"
] | [
false
] | [deleted] | [
"Bell's theorem shows that in general, a local hidden variables theory can't explain the correlations within quantum mechanics. As you have pointed out, the demonstration used within the proof is to consider a maximally-entangled pair of particles.",
"In principle, each nucleus in the universe could have a hidden... | [
"I tried to answer your question when you first wrote it, but had trouble because I'm not sure what you want. Are you wanting to say that quantum theory is not a hidden variables theory in some cases, but then magically becomes one in others? ",
"The point of Bell's theorem is that we can invalidate local hidden ... | [
"I tried to answer your question when you first wrote it, but had trouble because I'm not sure what you want. Are you wanting to say that quantum theory is not a hidden variables theory in some cases, but then magically becomes one in others? ",
"The point of Bell's theorem is that we can invalidate local hidden ... |
[
"What affects whether rain comes down hard or soft?"
] | [
false
] | null | [
"The atmosphere everywhere (even outside the cloud) contains lots and lots and lots of water. And under a stable combination of temperature, pressure, and humidity, all that moisture is perfectly happy to exist in a completely gaseous state. But as differing air masses start to collide, the local atmospheric condit... | [
"Interesting, thanks!"
] | [
"That wasn't a very good answer.",
"You can get rain just fine without \"clashing air masses.\" Violent supercells can form in the warm sector of extratropical cyclones when conditions are right, far away from \"clashing air masses.\" And winds are caused by the pressure gradient force, not temperature differen... |
[
"It's possible to explain the gravitational force with geometry, as the curvature of spacetime. Is it possible to explain other forces (like electromagnetic force) with geometry too?"
] | [
false
] | null | [
"Yes. The mathematical framework is gauge theory. In particular, the fundamental forces of the standard model are a specific type of gauge theories called Yang-Mills theories.",
"Roughly, the wavefunctions of particles \"charged\" under the interaction are thought of as taking values in a thing called a bundle, w... | [
"the geometric picture is more general than the field picture because the field picture completely misses global/nonperturbative/topological phenomena such as instantons or topological defects (monopoles, cosmic strings etc.).",
"It was proven that this kind of stuff has very important physical consequences, whic... | [
"and which model is the correct? does using either have advantages/disadvantages?"
] |
[
"As the moon was a lot closer to the Earth in prehistoric times, do we know how much more of an impact it had on the tides, if any?"
] | [
false
] | null | [
"The Moon has been around for longer than life on Earth. Its distance to Earth is ",
" increasing, but a million years is nothing here. Tides a million years were the same as today, neglecting local topography changes. Even if you go back tens of millions of years the distance to the Moon wasn't that different. T... | [
"To add to this, as ",
"/u/mfb-",
" mentioned there are a lot of influences on tidal range and teasing this out in the past is challenging. If we go back far enough in the geologic record though, we can use ",
"rhythmites",
" to constrain some aspects of the Earth-Moon system that were different. Specifical... | [
"I believe what you want to answer the followup questions is the source material for the review. ",
"Williams 2000",
" and in particular table 1."
] |
[
"What methods are there for solving the quantum many-body problem?"
] | [
false
] | null | [
"Ab initio methods, effective field theories, lattice field theories, mean field/Hartree-Fock, configuration interaction/shell model, cluster expansion, density functional theory, phenomenology, etc."
] | [
"Well the question is very broad, and there are many approaches to solving quantum many-body systems. These are all specialized techniques that people use to do so. "
] | [
"Ab initio methods",
"Generic term for any method starting from some low-level \"first\" principle rather than some high-level effective model. E.g. in solid state physics, a density functional theory is usually considered \"ab-initio\", whereas a tight-binding model is not.",
"effective field theories",
"The... |
[
"how does fat and protein digestion works? difference between lean and fatty protein and the effect on digestion time?"
] | [
false
] | Hello altogether, unfortunately I have many different questions about all things fat and protein digestion, specifically regarding animal products with different fat content. I want to understand the science and the chemistry behind the whole topic and also educate myself even further because it seems like I know nothi... | [
"GI physiologist here: absorption of food stuffs depends entirely on chemical composition of the food. The food must move from the lumen of the gi tract across the walls of the cells lining the the\nsmall intestine and thence into the bloodstream. The cell walls are composed of lipid (fat), thus only fats can cr... | [
"That was a very thorough and easily understood explanation. One might even call it... digestible.",
"What about other other foodstuffs? Like carbohydrates, vitamins, and minerals. I've heard some called \"water soluble\" or \"fat soluble\", does that affect absorption time?"
] | [
"Your body is extremely efficient at digestion of animal protein regardless of the fat content. Why do you ask exactly?",
"Regardless I highly recommend Lyle McDonald.",
"Start here"
] |
[
"Why will there be a shortage of Helium?"
] | [
false
] | I've read some articles talking about how the world uses up more Helium each year, and how hard it is to recycle, but I can't quite grasp (and it's never explained in any of these articles) how we're actually losing it. The way I understand it, Helium is an inert noble gas, and as such isn't used up in chemical reactio... | [
"Because Helium is the second lightest element, behind Hydrogen, it is lighter than air. We lose Helium by it escaping the atmosphere. Helium is generated through the radioactive decaying of minerals such as, uranium, thorium and monazite along with a few others that I know of.",
"Sources: ",
"http://en.wikipe... | [
"Would we get an abundance of helium in the future if we manage to get nuclear fusion power plants working effectively? Fusing hydrogen produces helium, am i right?"
] | [
"So my hypothesis is true? And just about how much per time unit is lost due to this?"
] |
[
"What is this black magic? Is there any secret connection between sqrt2 and pi or is this just a weird coincidence?"
] | [
false
] | null | [
"cos(pi/4) = sin(pi/4) = sqrt(2)/2",
"-cos(3pi/4) = sin(3pi/4) = sqrt(2)/2",
"cos(7pi/4) = -sin(7pi/4) = sqrt(2)/2"
] | [
"Do you know what sine and cosine represent, in regards to circles and triangles?"
] | [
"If you have a right triangle, with an angle t (in radians), then sin(t) is the length of the side opposite the angle divided by the length of the hypotenuse. At pi/4, you get a right triangle with equal length sides, and the Pythagorean Theorem says that if these sides have length 1, then the hypotenuse has length... |
[
"What happens when you sprinkle solid table salt on solid ice, assuming both objects and the surrounding air are -1C and 1atm?"
] | [
false
] | I am asking about what would happen in this hypothetical arrangement but I am also curious about why salt is used in making ice cream and melting road ice. It doesn't seem like there would be enough chemical interaction between 2 solids for melting points to change. | [
"You're right - there isn't enough chemical interaction between the two solids. However, the temperature of the solid ice (-1C in your hypothetical arrangement) is representative of the average thermal energy per particle, so there are a small number of the molecules that have a higher than average thermal energy a... | [
"I assume you mean decrease the melting point rather than increase."
] | [
"I assume you mean decrease the melting point rather than increase."
] |
[
"Why won't you feel the G-force of a forward-moving vehicle, even when going a possible 600 mph in planes? (reposted)"
] | [
false
] | [deleted] | [
"A vehicle moving at a constant speed parallel to the surface of the Earth (such as a passenger aircraft) exerts no g-force. You will only experience that force in a vehicle that is accelerating or decelerating.",
"The same is true in a car. When you accelerate from a stop sign, you feel a g-force pushing you b... | [
"The owner of the company I work for is also a champion drag racer. I had the opportunity to chat with him a couple months ago, and asked how many Gs his car generates. His answer was between five and six.",
"Granted, this is a car that drives 400 meters in ~3 seconds, but still..."
] | [
"The force you feel during acceleration is because of the differences in momentum. Your body is at rest and wants to stay there. The car you are in is accelerating forward. The seat pushes against your back. When you are up to cruising speed, the car stops accelerating, and your momentum is equal, so you don't ... |
[
"Why is it that when you film opposing mirrors' reflection of each other, it sort if looks like light decays with each reflection? Picture inside."
] | [
false
] | Why does "the bottom of the well" look dark as if the depth creates a shadow? What's going on here? | [
"Because mirrors are not perfectly reflective. Each time light is reflected from a mirror, some percent of the light is absorbed by the mirror. For a typical household mirror, roughly 10% of the light is lost per reflection, so by the time you get \"5 levels deep\" of reflection, the light has reflected 10 times, a... | [
"I think you got the maths wrong there. 0.9",
" = 0.35 , which is closer to a third."
] | [
"Also this is the reason that the color slowly becomes more green over time. The mirror backing is silver which starts reflecting much better around blue wavelengths and increasing to near 100% at green wavelengths (500 nm roughly) so that the higher frequency terms drop out. You can use this reflection method to... |
[
"Does antimatter produce \"anti-fields\"?"
] | [
false
] | A positron presumably has a "positive" field around it, like a + ion, but what about, for example, magnetism? Would a magnet made out of anti-Fe affect a coil made out of "normal" iron in the same way? What about gravity? Do anti-particles fly away from each other? And nuclear forces? There are more examples, so feel f... | [
"Most assume that the laws all behave the same for antimatter. It makes the most sense. The biggest difference between a proton and a positron even though one is ordinary matter and the other antimatter is their mass to charge ratio, but otherwise they behave similar. However, there are two caveats: CP violation, a... | [
"Matter and anti-matter behave exactly the same under three of the four known fundamental forces, gravity, electromagnetism and strong force. They behave slightly different under weak interactions. All the phenomenon you have talked about are either electromagnetic or gravitational in nature so there is no differen... | [
"Your mental picture is actually a bit backwards.",
"First, what is a field? A field is anything which is defined over all of spacetime. There's the electric field, which you obviously know very well. But there's also something called the ",
" which despite the similarity in names is entirely different. The ",
... |
[
"How do planets orbit Binary Star systems? Is it possible for the planet to enter a a stable orbit in a 'Goldilock zone?'"
] | [
false
] | null | [
"Is there a specific distance from a binary star pair where it makes more sense to treat it as a single additive gravity well? ",
"Sounds like a distance that should be named after some dude who came up with the formula about which I am curious as to its existence. If you know what I mean. "
] | [
"Is there a specific distance from a binary star pair where it makes more sense to treat it as a single additive gravity well? ",
"Sounds like a distance that should be named after some dude who came up with the formula about which I am curious as to its existence. If you know what I mean. "
] | [
"There are a variety of orbital architectures that would allow a planet to stably orbit a binary star system, but perhaps the simplest configuration would be a close binary system with a planet in a more distant orbit. In fact, ",
"the planet Kepler-16 b",
" is a roughly Saturn-mass planet orbiting two very clo... |
[
"Why is stable nuclear fusion hard to achieve?"
] | [
false
] | What is stopping us from finishing the technology? | [
"While fusing light elements together yields a positive amount of energy, the circumstances for such a process to take place are very hard to achieve. You can't simply throw some hydrogen or other light elements together and let it run as the probabilities of fusion occurring under normal conditions are astronomica... | [
"I like that you mentioned ITER. I really wish more people knew about this and get as excited as I am. This machine is going to do a lot for pushing humanity towards sustainable fusion.",
"Check out their website, it has awesome 3d models of the tokamak reactor.",
"https://www.iter.org"
] | [
"Thank you for the answer. This is great. It will be interesting to see if the one in France works out. "
] |
[
"What determines which toxins are filtered by the kidneys and which by the liver?"
] | [
false
] | Also, I've read that some chemicals are filtered by both but in different percentages. It seems kind of arbitrary. | [
"The liver and kidney have two different functions when it comes to dealing with toxins. At the kidneys, toxins are excreted. Plasma is filtered through the ",
"glomerulus",
" into the nephron, which filters out cells and large proteins. Although lipid-soluble toxins might be able to slip through the nephron wa... | [
"While this is all basically true, there are a number of waste products excreted in bile"
] | [
"the only way a water-soluble toxin is getting through is with a transporter.",
"Wouldn't these make their way into our bloodstream much sooner than when they reach the kidney?",
"Also, this got me think, if I drink a glass of water now, how long before those water molecules reach the kidney? And what path do t... |
[
"According to the law of conservation of energy, \"...energy can be neither created nor destroyed...\" as a result of this, in almost every reaction there is a certain amount of energy 'lost' as heat. My question is what happens to that heat energy?"
] | [
false
] | Coldness is just a lack of heat energy right? So if energy can't be destroyed, why hasn't the universe heated up to an unlivable point due to all the extra heat being generated? and by extension, what actually happens when heat "dissipates"? | [
"Heat that is \"lost\" or \"dissipated\" is simply dispersed in the environment. So when the brakes of your car cool down, air around them warms up. This air is mixed with air from the environment to the point where the increase in temperature is no longer measurable."
] | [
"Now I get what you meant. Infrared emitted by the Earth into space carries away heat, and this way the Earth cools down.",
"Same goes for the Sun, stars, etc, they emit electromagnetic radiation (infrared, visible light, UV...) and this carries away their heat. This energy is not \"destroyed\" in the sense that ... | [
"Imagine the energy distribution of all the universe. This energy distribution is not uniform throughout the universe. There is more energy concentrated in some places, like at center of galaxies, and less energy concentrated in other places, like between galaxies.",
"Basically, when the energy is 'lost' in heat,... |
[
"What is the optimal design to maximize the height that a self propelled 'buoyancy rocket' reaches after exiting the water? as well as optimal starting parameters (depth, volume of projectile)"
] | [
false
] | [deleted] | [
"The main thing slowing your beach ball down is drag from the water. Make your toy more streamlined and it would move much faster towards the surface. "
] | [
"You want to maximise the volume (to increase buoyancy), minimise the mass (to reduce weight), and minimise the cross-section of the object (to reduce drag).",
"The buoyancy force is the volume of your object multiplied by the density of water (rho=1kg/m",
" and by g=9.8 m/s/s (F=rho g V) - this nicely gives th... | [
"but one would assume there would be less drag on the tennis ball, but it does not reach 'escape velocity' while the beachball will pop out of the water some height, so there must be a function of volume"
] |
[
"Is it possible for a standing urinal to erode from people unrinating on it constantly similar to landscape changes due to weather? If so, how long would it take before a hole was formed through the urinal?"
] | [
false
] | I've wondered with millions of people possibly urinating all the time especially in high traffic areas (e.g. restaurants, airports etc..) would the urinal be urinated in enough to the point where the urinal would no longer serve to be useful and if so how long would that take? | [
"Fired ceramic is extremely durable; we're talking thousands of years...thus we find pot sherds in the archaeological record that are broken, yet not terribly worn or eroded in other ways. ",
"Ceramic, especially when glazed, is also significantly acid-resistant. ",
"So basically, it would have to be peed on pr... | [
"Check this similar question out"
] | [
"Geologist here, this process would be akin to the chemical weathering of rock and over 10",
" to 10",
" years. There would be a very gradual dissolution of the ceramic (aluminum oxide) rather than a physical erosion of the toilet. Aluminum oxides are very stable chemically but over time even they will dissolve... |
[
"Since IMAX cameras use film, how is CGI implemented into the movie?"
] | [
false
] | I'm not sure if this counts as a science question, and I couldn't find any other place to ask this. I'm using a throwaway just in case. | [
"Slightly besides the point, but not all IMAX cameras use film. There have been digital IMAX cameras for about 5 years, and newer digital IMAX cameras can shoot in 4k resolution. ",
"As for how digital effects are added to analog film - the film is scanned, frame by frame, into the digital domain. Once in the ... | [
"No I meant how do they digitize the footage if it is on film. I was under the impression that scanners could not scan such a high resolution but I guess they can. Of course it's added in post, but the other guy cleared it up by saying they were scanned, which makes sense I just didn't know how awesome their scanne... | [
"You seem to be under the impression that a cinema has separate projectors for the movie and for the CGI, this is not the case.",
"Normally CGI effects are added to film in the post production phase of the movie, after the physical shot has been taken. The script may call for \"Panning shot with giant robot\" so ... |
[
"Can we estimate what the CMB's frequency/wavelength/energy was when it was first emitted?"
] | [
false
] | We know that the hot, early universe emitted the CMB and it has been redshifted since then into the microwave range. Given what we know about the expansion of the universe and its history, could we estimate the frequency/wavelength/energy of CMB when they were emitted in the hot, early universe? | [
"Actually, this is pretty easy! Interestingly, along with several other predictions of Big Bang cosmology, the temperature of the CMB when it was emitted is very insensitive to details of the model.",
"When the universe was very hot, the universe was essentially composed of a dense plasma of free protons, electro... | [
"Mean free path was around 7000ly for photons afaik.",
"If it was millions, it would mean the vast majority of photons never hit the dense plasma, as this time period lasted less than a million years."
] | [
"While your argument makes sense to me, I did a quick google search (I'm too lazy to work it out) yielded ",
"this",
" which calculated the mfp near recombination to be 2.5 Mpc which is about 8 million ly, which is consistent with what I remembered from college.",
"So now I'm not sure."
] |
[
"How can electric devices and other sources of rather large voltages be lethal in water if the flow of electricity follows the path of least resistance?"
] | [
false
] | [deleted] | [
"Your guess is absolutely correct. If the phase (live) and neutral wires of your standard AC plug are in water, and you turn on power, very little current would flow through the majority of the bath. The current density between the two wires would be high, and you would not want to be there. But elsewhere in the wa... | [
"I also think it’s worth specifically pointing out that “current follows the path of least resistance” is misleading, because it doesn’t exclusively travel down the path with least resistance. Instead, it’s distributed proportionally to the amount of resistance in each path. So even if your body is a high-resistanc... | [
"This is especially true of downed high voltage wires on the ground. This causes a current gradient in the ground around the wire point of contact. While most of the current is flowing down into the ground, there is substantial current flow laterally from the point of contact. So if you stand with your feet spaced ... |
[
"What would happen to copper wire used as a equipment grounding conductor in the event of a lightning strike?"
] | [
false
] | In the 2014 National Electric Code, photovoltaic systems are required to have a supplemental ground linking the PV array to a grounding rod. We use bare 6 awg to be code compliant. What would happen to that wire with all the power from a lightning strike? If it matters, the system is already grounded with 10/8 awg stra... | [
"A lightning strike is in the range of 50C to 350C of electric charge transfer. An example of a very fast 50C charge transfer would be a 1.6MJ cap bank discharging through a 32mOhm impedance. An example current would be 1MA sourced from 32kV across a 1.6mF cap bank, which would dump most of its energy in about 50us... | [
"The arc will try to take the lowest inductance shape possible, so it will try to straighten out any bends and open any loops.",
"Ha! Never thought of that before. Groovy."
] | [
"ya oops, shoulda been highest instead of lowest. Higher inductance for a given energy would be lower current, which is higher entropy."
] |
[
"Why does rubbing or scratching an area after a workout cause it to itch?"
] | [
false
] | Whenever I get done working out, I'll sometimes rub my fingers through my hair or scratch an area on my body, and then it begins to itch uncontrollably - almost to the point of pain. Why does this happen? | [
"Not an expert, but:",
"Histamine is a vasodilator, and is often ",
"elevated when you exercise",
". Histamine is also released by the C-type fibers which signal ",
"itching",
". Basically, the exercise is raising the histamine levels in your blood to near the \"itch threshold\", and you scratching the ... | [
"The itchy feeling following a long run could be caused by the surface nerves being close to their thresholds from constant signals from the airflow. Add to that the increased histamine levels thepotoo mentioned, more specifically, increased histamine levels close to the surface of the skin because of capillary dil... | [
"The only time anything turns red and itches is in my ankles. I've sprained my right one twice and my left one once and it only happens during really long runs so I'm not too bothered by it."
] |
[
"Why do our bodies seemingly waste water through urination when water is essential for life? Is there not a better way to excrete urea than wasting something crucial to our survival?"
] | [
false
] | null | [
"Yes, water is essential for life and yes, too much water can kill you. ",
"That being said, the kidneys are incredibly efficient at saving water and they respond to several feedback systems in your body to help regulate this. ",
"Nitrogenous waste can be excreted as urea or uric acid. Urea is water soluble whi... | [
"There are several urea excretion \"schemes\" found in nature and they are largely related to the climate an organism lives in or it's lifecycle.",
"Retrieving/re-cycling water at your kidneys costs energy. It's only worth expending that energy if it costs a lot of energy to find and consume drinking water. So so... | [
"I can help. Your body only has about 5L of blood. Saying the kidneys filters about 180L a day is still correct. Your kidneys filters your entire supply of blood multiple times per day to insure that any toxins are filtered and excreted from our body."
] |
[
"Why are tardigrade so resilient and how CAN they be killed?"
] | [
false
] | null | [
"A tardigrade resilience mostly comes from its desiccated state. That is, when it is dehydrated and in \"hibernation\" so to speak.",
"When they are hydrated, they are prone to death by any form that regular lifeforms can experience. They arent immortal."
] | [
"Tardigrades are severely overhyped. The claims made about them are a lot like claiming that oak trees can survive temperatures near absolute zero, immersion in boiling water and exposure to space because you can do those things to acorns and have them germinate afterwards."
] | [
"Oh cool I didn’t know that! \nHaving no knowledge about what made them hard to kill I just assumed that they were always like that "
] |
[
"Are flat things actually flat?"
] | [
false
] | null | [
"Hi Snazzymf 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... | [
"I only have access to mobile, so I really have no clue how to add a flair."
] | [
"read the autogenerated comment in this post"
] |
[
"Why does light change its speed AND direction when passing from one medium to the other?"
] | [
false
] | [deleted] | [
"Here is a good analogy for why it happens",
" ",
"An interesting way understanding it is through Fermat's principle. You don't need to know anything about the wave/particle nature of light. You simply assume that the correct path for a ray of light to get from point A to point B is the one that minimizes its t... | [
"An analogy I was taught: imagine two wheels connected by an axle rolling along. If it rolls from tile (low friction) to carpet (high friction) at an angle, then the wheel that contacts first will slow down first - and the other wheel will swing until it contacts the carpet. This swinging motion causes the entire a... | [
"Read QED by Richard Feynman. That little book cleared a lot of fog in my head about light and its properties. I don't have a background in any of the hard sciences whatsoever, but was able to understand most of it without much trouble. Very well explained indeed."
] |
[
"How dangerous is it took look at the Sun [Details inside]"
] | [
false
] | [deleted] | [
"I dont have any numbers or papers to back this up, just wikipedia, but I want to post anyways just to be sure that this is said at least one.",
"She could can and will eventually do severe damage to hers eyes up to the point of blindness. She should not do this, period. ",
"http://en.wikipedia.org/wiki/Sungazi... | [
"Absolutely agreed, I can't believe that anyone would actually do that intentionally. You only get one pair of eyes."
] | [
"Makes me think how amazing it is that 7 billion of us walk around so non-chalantly when there is this great big blazing thing in the sky 8 hours a day that if we look at it for more than a few seconds we will go blind!",
"Something ought to be done to protect us from this evil menace!"
] |
[
"How come sea creatures are resistant to decompression sickness, but humans are so sensitive to it?"
] | [
false
] | null | [
"They’re resistant because they’ve evolved to survive in that environment. Air breathing marine mammals naturally slow their heart rate and collapse their lungs to try and minimize nitrogen levels in their blood. The physiology of marine mammals under varying levels of water pressure is very hard to study, but ther... | [
"If you're talking about the \"bends,\" humans breathe compressed air from tanks when they are deep underwater. Breathing compressed air and then surfacing too quickly can cause that air to decompress and create gas bubbles in our blood. This is the bends.",
"Marine mammals have a number of mechanisms to prevent ... | [
"Fish do have major problems with decompression because of gases in their swim bladders. If U bring up a fish like a grouper too fast you will from the depths over 100' or so U need to vent them or use a device that holds them and that U drop to 50' or so to release them (better method). "
] |
[
"How do elements (that are not amino acids) get organised in the body? Eg Fe in hemoglobin, Ca in tooth enamel."
] | [
false
] | I understand how proteins are formed by protein synthesis. But (from my clearly flawed understanding) should just be chains of amino acids. How do Fe ions get into hemoglobin? How exactly does Calcium get into our teeth? How are these elements transported and deposited? How is this process organised? | [
"I have no knowledge of how teeth is mineralized so I'll let the relevant experts explain that part.",
"Iron is stored in cells in ",
"ferritin",
" and in blood in ",
"transferrin",
".",
"Heme",
" is the part in hemoglobin that contains the iron, but it's actually not made of amino acids. It is a ",
... | [
"You are exactly right, it doesn't always work perfectly. Here's an example:\n",
"Transition metals modulate DNA-protein interactions of SP1 zinc finger domains with its cognate target site.",
"The metal free apoprotein of recombinant human transcription factor SP1 was used in metal reconstitution experiments t... | [
"It's pretty clear that there are a number of ways which inorganic ions are dealt with in biological systems, a number of which have been discussed by the other commenters. I would also point out that there is evidence for metal chaperones inside the cell given the ",
"case of copper",
" as well. "
] |
[
"100 low-power appliances into single plug socket?"
] | [
false
] | A picture was recently posted with a dodgy 10-plug setup, but apparently it was safe because the items were only low-power devices such as phone chargers etc. Is it possible to buy ten 10-way plug sockets, and plug in 100 low-power appliances without danger of overload? In theory, if they're only around 10 watt each, i... | [
"The typical \"circuit\" in a house in the USA is rated for about 15 or 20 Amperes (sometimes only 5 or 10 A). One circuit can feed one outlet, or multiple outlets (including light fixtures). If you have 100 devices that each draw 0.15 A (150 mA) or less, then, it is possible that one outlet can safely feed all of ... | [
"note this is 15 or 20 amps at about 110v what you need to know is the wattage. of the device which is W=VI and your total available wattage on the circuit in this case 1650 or 2200. also note this is not precise home electricity has power highs and lows that 110v will vary a bit. Also that power rating on your dev... | [
"This should not be an issue so long as the upstream \"trunk\" power bar is rated to handle the whole load (9 A or so at 1 kW)."
] |
[
"Are end-stage Alzheimer's patients still conscious?"
] | [
false
] | null | [
"this is largely a philosophical question. AD can get to the point (before it outright kills you) where you are unconscious, but there is also the time before then where the patient is not exactly asleep but certainly not there completely either. is that what you call consciousness? what do you base it on? mini men... | [
"Yes. Alzheimer's effects areas like memory, language, thought (executive functions), behavior, personality and mood, and determining relation to other objects (sitting in a chair). The most noticeable changes over time will likely be personality/mood, memory, and behavior. Some changes in behavior (irritable, lyin... | [
"Most of what you are describing is not advanced Alzheimer's."
] |
[
"How can the melting point of chocolate be determined by its crystal structure?"
] | [
false
] | I've been learning to temper chocolate recently. The basic idea of chocolate tempering is that cocoa butter can form any one of six different crystal forms, four of which have undesirable properties. The way you go about making sure you have the right kind of crystals is by melting your chocolate completely, then cooli... | [
"Crystal structures all have an inherent stability, the more stable the higher temperature (more energy) is required to break down the structure. ",
"So in this case the form IV crystals are both less stable and undesirable and your method allows you to raise the temperature of chocolate (so no crystals exists) a... | [
"The naive view that a melting point is a property of elements acts perfectly when looking at elements and simple molecules. However, when you have a massive organic compound like cocoa butter this simplification doesn't work. ",
"The reason why not is that there are two main contributors to stability, entropy ... | [
"My naive understanding was that a substance's melting point was a property of the elements it contained, but in this case the exact same substance can have six different melting points.",
"Melting point is the point where the thermal energy of the material begins to break the lattice bonds that hold the solid to... |
[
"Could someone explain coding regions and regulatory regions in genes and how mutations in each region affects the organism."
] | [
false
] | Hopefully someone will be nice enough to help me out. I'm in a zoology class and this information is extremely important but I never learned it and have trouble finding information on it. None of my classmates can seem to explain it well. So what are the coding regions and regulatory regions in genes? I know it has som... | [
"The most important thing to remember about genes, is that they only represent a potential for protein formation and potentially metabolic activity. The presence of the gene alone does not indicate how much, if any of the gene product will be synthesized, how quickly it will be synthesized, etc. ",
"There are a... | [
"Intro to molecular genetics: ",
"http://freevideolectures.com/Course/2305/Introductory-Biology/13",
"Gene regulation specifically: ",
"http://freevideolectures.com/Course/2305/Introductory-Biology/13"
] | [
"A gene is part of your DNA that codes for a protein. A signal at the beginning of a gene says \"start here\", and then every three nucleotides (building blocks of DNA) code for one amino acid (building block of protein). The coding region is the part that becomes protein after translation by ribosomes.",
"The ... |
[
"Dark Matter"
] | [
false
] | What is it? What evidence do we have for its existence? I know that I could just as easily open up the Wiki article, but I was hoping for a more "layman's terms" approach. Anyone know anything about this off the top of their head? | [
"Dark matter is the matter which makes up most of the matter in the universe. It is dark in the sense that its mass to light ratio is very large. The current best candidate for what dark matter is, is ",
"weakly interacting massive particles",
"... essentially heavy particles that can exist in extensions to the... | [
"The rotation of our galaxy is prime evidence for Dark Matter. We are in a spiral galaxy and if visible matter was the only gravitational input to the system, then the center would spin faster then the distant tendrils. Kind of like a small boat in a whirlpool, the closer to the center you are, the faster your angu... | [
"Dark energy is just the opposite of Gravity. As the distance between objects (galaxies) increases, the force accelerates them apart (with increasing force). In 2003 NASA scientist did a study called WMAP which measured the total amount of energy of the Universe and the speed of other galaxies. If Total Energy (TE)... |
[
"Do planets of larger stars scale proportionately?"
] | [
false
] | Obviously there will be variation, but are the planets of larger stars super massive? Like there are stars that are mind bogglingly huge when compared to the size of the sun, so do they have super massive planets that are proportionate to the Earth to sun or Juptier to sun even? | [
"We do not know yet. Planets around massive stars are very hard to detect as they are: very bright (so transit is hard) and very massive (so radial velocity is hard). A few planets have been discovered around massive stars but our statistics of them are not sufficient to be able to say much other than \"massive sta... | [
"There are definitely planets much larger than Jupiter orbiting stars much smaller than our sun. I’m not sure if we have enough data to say for sure if there’s a direct correlation between star and planet size. I think it would make sense if it was the other way around, where larger stars only have small planets, s... | [
"Based on our admittedly quite limited data of exoplanets, there does seem to be a trend for more massive stars to more often host giant planets. But:",
"1, More massive does not always mean larger. Most stars go through a dramatic expansion in the “red giant” phase near the end of their lives, so an old, low-mas... |
[
"Energy required to get into space vs energy requires to lift off a plant and travel around the world."
] | [
false
] | Myself and a friend where have a argument on which would require more energy/fuel consumption, a spacecraft lifting off and breaking the atmosphere and reaching space, vs a airplane(say one of similar size) to lift off and travel around the world(in mostly ideal conditions). | [
"Getting to space requires more energy.",
"The Space Shuttle requires ",
"835,958 gallons of fuel",
" and we have not even accounted for the solid rocket boosters. The Space Shuttle (orbiter) weighs in around ",
"171,000 pounds",
".",
"A 747-400 (empty) is about ",
"400,000 pounds",
". The 747-400... | [
"Well, a Boeing 777 can hold 48,000 gallons and uses a 6 gallons per mile, so ignoring takeoffs and landings that's 24,000 miles * 6 gpm = 144000 gallons.",
"The space shuttle used 146,000 gal oxygen + 395,000 gal hydrogen plus the solid boosters. So definitely more.",
"Most if not all conventional launch vehic... | [
"There aren't any human piloted planes that can circumnavigate the globe on a single tank of gas. To find the range of a plane you have to integrate over the weight of the plane since its efficiency changes as it burns off gas, so I'm not sure how much sense it makes to extrapolate distances and fuel by simply mult... |
[
"How does chlorine gas kill you?"
] | [
false
] | null | [
"Chlorine gas will react with the water in the mucous/linings of your lungs and form hydrochloric acid. This will destroy your lung's ability to take in oxygen and will be very painful. Enough gas and you will die from lack of oxygen."
] | [
"Chlorine produces hydrochloric acid on contact with water as per the following equation:",
"2Cl2 + 2H2O -> 4HCl + O2",
"Thus, it creates hydrochloric acid on any exposed water on your body, especially in your lungs. Since it also reacts with the water in your eyes, it was used as a chemical weapon in the First... | [
"Chlorine is a reactive chemical, quite like oxygen actually (actually not as bad as oxygen), but our bodies are designed to deal with oxygen so we don't get poisoned by it. What chlorine does is it corrodes moist surfaces (like the inside of your lungs) by getting into the water and forming acids. If your lungs ar... |
[
"Is it possible for a person to get moldy?"
] | [
false
] | Do humans have a natural biotic defense against mold, or is it something else entirely? | [
"A guy I knew had a liver transplant and he took drugs to suppress his immune system. He had to go to hospital from time to time to be treated for fungal infections.",
"My nephew was in hospital for many months with fungal meningitis. He had fungus growing in his brain."
] | [
"Interesting question. Fungi are eukaryotes like us, so it's a challenge for our immune system to mount a defense that doesn't affect our own cells as much as the fungus - especially since the few pathogenic fungi out there are complex enough to have mechanisms for 'cloaking' their own antigens so our immune system... | [
"In nature, bacteria and fungi are often in competition for food, and they are also direct threats to each other. Therefore they have developed strong defenses against each other (penicillin is a fungus-based antibiotic, after all.)",
"In humans (and all other animals presumably), this is has evolved into more of... |
[
"Why are galaxy arms stable?"
] | [
false
] | I know that galaxy arms are essentially density waves with stars moving in and out of the wave as they orbit around the galaxy centre. This part makes sense to me. The arms are brighter than the areas between them, and arms being brighter means that there are more stars and is therefore more dense. However, I don't und... | [
"That's actually a really insightful demonstration of how that particular analogy is only ok at describing the real picture! Here's a better (and hopefully still comprehensible) description of what's going on:",
"Ignore the galaxy for now, just picture a blob of gas floating in space. If it's all by itself, the... | [
"As far as I understand, the modern theory tells us that the movement of stars in galactic arms does not define the \"shape\" we see.\nAn arm is a density wave indeed, but it really consists of (invisible to us) gas and dust clouds. This density spike at the front of an arm creates lots of stars - big stars, hot st... | [
"Isn't it because orbits are not circular, but, instead elliptical? As a result, when stars reach \"Apogee\" (most distant point from center on their elliptical orbit) they are going their slowest and when they reach \"Perigee\" (most close point on orbit) they are going their fastest. Also, orbits \"precess\" aro... |
[
"how does the magnetic strip on train tickets work?"
] | [
false
] | I'm a dunce, so the dunce version of the answer is appreciated! | [
"They are essentially like a strip of audio casette - a strip of material with embedded iron particles, which is magentised in such a way that information is ",
"encoded onto it",
".",
"A train ticket will encode information like the station the ticket was purchased in, the date and time of purchase, train op... | [
"It is basically just a strip of ",
"magnetic tape",
" glued to the ticket. The principle of operation is the same as for audio cassette tapes if you're old enough to remember those. There's a good explanation ",
"here",
"."
] | [
"The magnetic strip is like audiotape....it is a thin coating of particles that can be magnetized. When written, a series of magnetic stripes is created that are perpendicular to the length of the stripe. Some of these stripes are oriented with North on top and South on the bottom, the others are the opposite way a... |
[
"What is the optimal angle to launch a projectile to achieve maximum distance?"
] | [
false
] | If I had a gun, and wanted to send the bullet as far as possible. What angle would I raise the gun to? 30°? 45°? Etc. | [
"Big naval guns also take into account air pressure, humidity, and the rotation of the earth. In WWII these calculations were done by, calculators, people working deep in the ship on complex mechanical devices that would work various, small, parts of the problem to come up with the final solution. Of course the obj... | [
"Big naval guns also take into account air pressure, humidity, and the rotation of the earth. In WWII these calculations were done by, calculators, people working deep in the ship on complex mechanical devices that would work various, small, parts of the problem to come up with the final solution. Of course the obj... | [
"ohh finally I get to contribute something meaningful to askscience",
"see ",
"here",
" for a video on these ",
" analog computers. I study computer science myself, and this blew my mind.",
"There is a full article on these absurdly interesting devices ",
"here",
", find more videos on page 2."
] |
[
"How do experts come to know that the recent British strain of COVID-19 is ~ 70% more transmissible?"
] | [
false
] | Is it because the virus needs less of its particles to infect? Is it longer lasting in the air? What exactly makes it more transmissible and does that change the currently accepted measures (masks or distancing making less of a difference for example)? Thanks! | [
"Firstly, it is ",
"no longer believed to be 70%",
". ",
"That figure was based on ",
", which provided values with large confidence intervals. The more information we get, we can reduce those confidence intervals. The values are now around 30-56%"
] | [
"There's several mutations in the spike protein, some in the receptor binding domain, the business end of the Spike that docks with the ACE2 receptor and hacks into cells.",
"Of these, N501Y seems to be the mutation that's most important, makes the Spike stick more strongly to ACE2. Interestingly, they modified a... | [
"Thank you, interesting read. So assuming it's around 50%, how do researchers explain this in simple terms? I still don't quite understand what makes it more transmissible than the other strains that remained more or less unremarkable to the public"
] |
[
"Why is the needle put in the upper arm or the buttocks for common injections, but near the inside of the elbow for drawing blood or doing IVs?"
] | [
false
] | Had some blood tests done a few days after getting some booster shots (I got myself vaccinated even though I hate needles :D) and had this thought about the position of the needle. Does it have to do with the location of particular major veins? Whether the needle needs to find a blood vessel? Blood pressure? Upstream/d... | [
"The top of the arm and buttocks are for intramuscular injections. That is to say the serum goes into the muscle fibre. This causes the serum to be gradually released I to the bloodstream and doesn't require accuracy to find a blood vessel.",
"In the arm the needle will go into the vein directly and the serum is ... | [
"The injections on the upper arm or butt are intramuscular, not intravenous. When collecting blood, they obviously need intravenous, and your veins are easy to see and get to in the inner elbow.",
"Why some intramuscular shots are in the arm and some are in the butt, I don't know. "
] | [
"The placement of the shot all depends on the quantity of the injected substance. The gold standard is that anything in the deltoid (arm) should be no more than 2 milliliters. However, since the gluteus Maximus muscle (butt) is much bigger you can give up to 5 milliliters into it."
] |
[
"Why is liquid helium used to cool down superconducting magnets?"
] | [
false
] | This might be more of an engineering question now that I think of it. Liquid helium is used to cool down the superconducting magnets in the NMR machine in my lab. I figure, since it is so rare, can't we encase the magnets in a solid ice with a solid-liquid transition temperature below the superconducting temperature of... | [
"Liquid helium has its transition temperature at around 4k (-269 °C, -452 °F) at one atmosphere, and another phase transition to/from superfluid at around 2k. ",
"The coldest melting point (excluding Helium) is for Hydrogen, which had been ",
"shown",
" to be usable as a coolant, although I think it's not bei... | [
"If you look at a phase diagram for water, the entire solid-liquid coexistence line is contained within some small interval around 0 degrees Celsius. That’s not cold enough for superconducting magnets.",
"Liquid helium is used to cool things down to around 4 Kelvin, which is around -269 degrees Celsius."
] | [
"It's much easier to cool a gas than a liquid, since we can take advantage of gas expansion to cool it down. You can take a warm gas and compress it to high pressure, which heats it up. You let the hot, pressurized gas shed its heat with conventional cooling (heat exchangers, cold bath, etc.), and quickly decompres... |
[
"If a particle has the probability of being in two places at once, then is it possible to use a particle accelerator to accelerate the particle to a high energy and into the two slits and then place two detectors, with one at each slit, to convert the energy of the particle into electricity?"
] | [
false
] | Since the particle has become two particles, will this allow the total power output of the two detectors to be higher than the input power from the accelerator? This is assuming that the accelerator is 100% efficient. | [
"The particle never becomes two particles. If you ever measure its position, it is in just one place. In between measuring its position, its 'wavefunction' may spread out (and interfere with itself etc. etc.), describing where it ",
" be, but there aren't actually multiple particles.",
"So no, this won't work. ... | [
"The particle accelerates does not split into two particles, it behaves as wave. It only acts as a particle when measured. Also, you could not extract any more energy from the system than you put in, even if it were to spontaneously split into two particles, the total sum of energy of those two particles would be e... | [
"I think you have a bit of a misunderstanding of quantum mechanics. A particle does not have the probability of being in two places at once. It ",
" at several places at once* and you have a certain probability to ",
" it in one of those places (e.g. 50% at each of the detectors placed at the slits of the doubl... |
[
"Does black holes absorb dark matter and/or dark energy?"
] | [
false
] | null | [
"For the most part, \"dark energy\" is currently modeled as a gravitational effect that's either not present or completely negiligible at the scales on which a black hole operates. It isn't a \"thing\" that can be absorbed.",
"Dark ",
" on the other hand, could in principle be absorbed by a black hole, provided... | [
"thank you for your answer"
] | [
"Would this have any effect on the black hole"
] |
[
"When a person gets a cut, is it better to wipe off the blood or let the blood coagulate to protect the cut?"
] | [
false
] | null | [
"Hi, medic here! It depends. For the sake of the conversation, I'm going to assume you mean something like a run-of-the-mill, basic cut. You nicked yourself shaving, or your knife slipped a little when you were cutting veggies. Nothing that would require sutures. ",
"Typically, its best to wash the cut with antib... | [
"Typically, its best to wash the cut with antibacterial soap (like Dial) ",
"In the US, isn't antibacterial soap now outlawed (to normal consumers)? Because of the massive introduction of antibiotics to the environment leading to resistance?",
"exsanguinated",
"fun word"
] | [
"This response is amazing! Thank you so much!"
] |
[
"What causes a paper helicopter to fall very slowly while spinning?"
] | [
false
] | My dad is a primary school teacher and one of his favorite experiment is to have the students make . It is a simple Y-shaped piece of paper with something heavy tied to the bottom (a paper clip, a staple...) that, when dropped, starts spinning and takes a long time to fall. ( ). We were wondering, what exactly causes t... | [
"In aerodynamics, we consider the wing as being static in a wind, as opposed to moving thru the air. A wing does not care about its angle with respect to the ground. It just cares about where its wind is coming from. If you have forward velocity and are falling at the same time, this relative wind comes at you from... | [
"The paper had gravitational potential energy only when you drop it (mass * g * height) which is converted into kinetic energy (the paper falling) and rotational/angular energy (spinning). The sum of the falling+rotational energy must equal the initial gravitational potential energy. ",
"The faster it spins the s... | [
"Very interesting answer. Thank you!"
] |
[
"If asteroid 2012 DA14 hit a communications satellite, what debris cloud would result?"
] | [
false
] | The asteroid , will skip past the earth on 15th February at the distance that some satellites orbit. Would a collision cause debris similar to the recent or would it have different characteristics? | [
"According to the ",
"Asteroid 2012 DA14 FAQ",
":",
"The asteroid will not hit a geosynchronous satellite (satellites that are in an orbit allowing them to stay above the same point on Earth all the time) because it is coming inside that ring of satellites, and because those satellites are in equatorial orbit... | [
"That's pretty generous to think that all that debris isn't going to contribute to our growing \"space junk\" problem and will all burn up. "
] | [
"An office building sized rock moving at almost 30,000 FPS is not going leave much in its wake."
] |
[
"I saw this picture and was wondering why this phenomena occured."
] | [
false
] | null | [
"*this phenomenon"
] | [
"The flare is the interaction of the sun with the glass/material of the camera lens. It is actually occurring around all of the light sources in the picture. "
] | [
"I may not remember correctly, but I'm pretty sure that's why space telescopes located on earth are at very high altitudes, where the air is less dense. "
] |
[
"Why does squinting help bring my vision into focus?"
] | [
false
] | Title | [
"Two possibilities: (1) you are actually physically bending your lens in order to correct it, or (2) you are simply reducing the field of few which allows a higher % of the incident light to hit near the center of your lens where it does not need to be corrected. Based on the evidence I've seen (holding a piece of... | [
"Because you are reducing scatter, and turning your eye into a ",
"pinhole camera",
"."
] | [
"The piece of paper with a hole (and maybe the squinting eye) works the same way as a ",
"pinhole camera",
". "
] |
[
"Resources for Nuclear vs. Coal"
] | [
false
] | [deleted] | [
"IThEO Presents IThEMS",
"Slower Breeding at Modestly High Temperatures With Thorium. ",
"4th Generation Nuclear Energy Designs Like Thorium MSR’s and IFR’s Have Inspired Film Maker Robert Stone",
"http://thoriummsr.wordpress.com/2010/09/27/q-and-a-with-david-leblanc-canadian-thorium-expert/",
"http://en.wi... | [
"My thesis is due at the end of next week so if i get it finished in time i will make it available here. ",
"It is on the environmental impact of various power stations."
] | [
"You are absolutely right and i apologise profusely but like i said in a previous comment, i have my thesis due this week along with other projects and exams in 2 weeks so i am a bit run off my feet and only have a few minutes on Reddit for breaks. I am doing a group project on Coal power plants so i will upload th... |
[
"Are bees singlehandedly responsible for most of plant pollenation?"
] | [
false
] | On Facebook, this picture just cropped up: Claiming that bees (presumably with pollenation) give us access to basically every fruit I've ever heard of, and I few I haven't. I've heard through the grapevine (which will apparently be amongst the lost), that the bee populations are dying off, but nobody seems to be in abj... | [
"Hi,",
"There are a few questions here, so excuse me if I'm a bit wordy, also, I work in honeybee biology, not specifically in their usefllness in agriculture, so I can't give you exact numbers, just points from things I've read / talks I've attended etc.",
"The short answer to the main question is no, they're ... | [
"Are there any crops that absolutely require bees specifically, in order to pollinate?",
"There's nothing that is 100% bee required. However, without the bees -- and by that, I mean the bees carted around for massive agricultural use, and not wild bees -- yields of almonds, apples, cherries (probably other rosid... | [
"Are there any crops that absolutely require bees specifically, in order to pollinate? Is there anything that a normal, urban, boring human such as myself, can do to slow the collapse of bee populations?"
] |
[
"Why do I look different in the mirror than on photos/videos?"
] | [
false
] | null | [
"A camera rotates the image and looks like the view another person has of you. A mirror on the other hand inverts the image in the plane parallel to your line of sight, which keeps the left on the left and the right on the right but turns them inside out."
] | [
"Cameras distort the face, specifically they flatten or exaggerate depth, altering features such as your nose, cheeks, and chin. Shorter focal length exaggerate the depths while longer ones tend to flatten your face."
] | [
"eli5 please?"
] |
[
"When Halley's Comet returns in 2061, would it be possible to attach a radio sensor or video camera to track its journey?"
] | [
false
] | null | [
"We can land a spacecraft on a comet. Done before. ",
"So we could attach something to the comet. ",
"Power would likely have to come from a reactor or radioactive decay but I really do not think that the lifespan would last the kind of time you are talking. Solar power would be difficult due to alignment issue... | [
"The thing is we know exactly how far out it goes - the whole reason we know when it;s coming back is because we know the orbit very precisely. And as far as getting 'close' to something - in the depths of space a close encounter may still involve millions of kilometers distance. Strapping a multi-million dollar d... | [
"What if, instead of sending a signal back, it stores the data, which we can retrieve next time it comes around?"
] |
[
"What is the physical significance of discovering the famed Higgs boson?"
] | [
false
] | Much focus by particle colliders such as the LHC seem to place a lot of emphasis on discovering the Higgs boson and what it means for the physics community. Why is this so? | [
"The short version is this: we found out that the electromagnetic force and the weak force were two aspects of the same force. But the photon is massless, and the particles that carry the weak force are really quite heavy. Well, the resolution was that there was this other field, the Higgs field, that the weak part... | [
"I'm afraid you got all of that wrong. The Higgs is not a supersymmetric particle; it's the last undetected boson predicted by the Standard Model. And it's got ",
" to do with gravitation.",
"The real story is that the W and Z bosons are massive, when they really ought not be under the old version of the Standa... | [
"This isn't nitpicking. The fact that the Higgs doesn't actually account for most of the mass in the universe is an important point to make. "
] |
[
"When new elements are created in the lab, why do we smash together individual atoms instead of just smashing two bigger clumps together?"
] | [
false
] | Surely if our goals is to perform thousands and thousands of collisions, wouldn't it be easier to collide larger clumps of atoms than single atoms? Or is it something about the acceleration process that prevents us from doing that? | [
"To reach the speeds at which collisions will cause the nuclei to interact, we have to ionize the atoms and accelerate them into a beam in a particle accelerator. There are many atoms in the beam - it's not as if we're performing the experiment one atom at a time - but the process of ionizing and accelerating break... | [
"Forming a high-speed beam of anything neutral is much, much harder than accelerating charged particles. Ions are simply the best form in which to accelerate nuclei to the speeds of interest."
] | [
"So why is it that they have to be ionized? Is it a necessity or does it just make things easier?"
] |
[
"Can a proton behave like a positive hydrogen ion? Can it form bonds with negative ions?"
] | [
false
] | null | [
"A proton is a positive hydrogen ion."
] | [
"A proton ",
" a positive hydrogen ion, and a positive hydrogen ion ",
" a proton.",
" A free proton will form bonds with literally anything that isn't positively charged, including ",
"helium atoms",
". You can find a list of calculated proton affinities ",
"here",
", courtesy of NIST. Note that thes... | [
"a positive hydrogen ion is a proton.",
" Before someone yells at me, yes, I know deuterium and tritium exist.",
"Just wanted to share this tidbit for you or anyone else reading this who might not know: this detail is actually related to how the proton got its name!",
"It's rarely used today, but there is an... |
[
"What makes something stretchy or sticky?"
] | [
false
] | Could someone please describe what happens at the atomic/molecular level as to why certain substances stretch/stick to other things. It sounds silly, but I'm really curious. | [
"Feynman explains rubberbands.",
"This series is pure gold if you have the time to watch it."
] | [
"Stretchy things are able to be deformed because there molecular structures are able to be deformed with relatively low amounts of force.",
"I'll assume you are talking about plastic/polymer type materials here, but similar things could be applied to metals pretty easily. Since I'm not sure of OP's background, a... | [
"You're correct with the stickyness but too, there are two types of adhesion, electrical and mechanical.",
"Electrical adhesion is all to do with the Van Der Waals forces and other intermolecular forces in other materials which simply hold the molecules together via electron distribution. (I could go into more de... |
[
"What does not emit electromagnetic radiation?"
] | [
false
] | My remote sensing textbook states "With the exception of objects at absolute zero, all objects emit electromagnetic radiation." I understand that an object doesn't have to emit it's own radiation, it can reflect another objects radiation. So what are the processes that cause electromagnetic radiation to be emitted? Wh... | [
"Objects are made of atoms and atoms are made of charged particles (nuclei and electrons). Charged particles emit EM radiation when they are accelerated. All objects at a nonzero temperature T undergo some form of thermal motion and these random vibrations involve varying velocity and thus accelerations. Therefore ... | [
"It's a phenomenon called Larmor radiation.",
"Warning: a bit of math.",
"The electromagnetic field of a moving particle is called the Liénard-Wiechert field and can be decomposed as a \"velocity\" part, function of just the velocity, and an \"acceleration\" part, function of both velocity and acceleration.",
... | [
"Thermodynamics tells us that anything that can absorb EM radiation will also emit EM radiation as a function of temperature. Anything made of atoms can absorb EM radiation, so anything made of atoms will emit EM radiation. This can be a continuous blackbody spectrum, which is a good approximation for most solids, ... |
[
"What is more efficient, a traditional gas motor powering the wheels, or the same motor generating electricity for an electric motor?"
] | [
false
] | My question comes from seeing things like the Chevrolet Volt. It has the convenience of being able to charge the battery and only use the engine if the battery dies. But I wondered if it were to only run off the gasoline engine generating power if its less or more efficient then just using that engine to power the whe... | [
"Gas engines are most efficient if they run at a constant fairly low rpm.",
"You could ",
"always drive at exactly 42 mph",
" (varies by vehicle) but that's boring and usually unsafe. Your engine could be optimized more if it didn't need to turn at such a broad rate of speeds.",
"Electric engines are really... | [
"What you're describing is nothing new to the Chevy Volt.",
"Only running it a combustion engine near it's peak efficiency point would produce favourable results",
"You also eliminate the need for a lot of mechanical components in the car",
"There's some correct and some incorrect here. The Volt is a paralle... | [
"That's what I thought would be the case. I couldn't find definitive proof online, but this seems to make sense. Thank you for the link as well, I will have to do some reading."
] |
[
"I saw a video of someone breathing in a rag of chloroform and getting instantly knocked out. I don’t think that’s real, but it made me curious. How does chloroform work? And what exactly does it do?"
] | [
false
] | null | [
"Using chloroform to knock someone out in a matter of seconds is entirely fiction.",
"Chloroform is basically an anesthetic--but one that is no longer used due to the fact that it can seriously damage your liver and heart. Even with perfect dosing, it would take at least 5 minutes of breathing it to knock someone... | [
"Dang it! One more thing to get angry about when watching fiction movies.",
"I wonder how many attempted kidnappings/murders/nefarious crimes were foiled by this misunderstanding?"
] | [
"Not to mention pretty much every detective show made in the 70's.",
"Getting instantly and harmlessly knocked out by a blow to the head is way overused to. What they don't show you is that 20% of them never wake up and another 20% have life long disabilities."
] |
[
"How big dogs have much shorter lifespans than smaller dogs, is it the same for humans? Say a 6' 7\" inch man vs a 5' 5\" man?"
] | [
false
] | null | [
"There’s a surprising amount of research showing that tall people have shorter \nlifespans than short people. This Slate article from 2013, ",
"I Wish I Was a Little Bit Shorter: The research is clear: Being tall is hazardous to your health",
", cites a bunch of studies, and since then even more have been publi... | [
"Another proposed reason is ",
"increased",
" ",
"risk",
" of ",
"cancer",
". ",
"Simply stated, more cells equals more chances for those cells to become cancerous."
] | [
"The short answer is yes, there is a solid inverse correlation between height and longevity within the normal range of human height. At the extreme upper end of height, longevity drops off very sharply, but the same happens at the extreme lower end as well. ",
"On top of that, height correlates very strongly wit... |
[
"Would earphones work in space?"
] | [
false
] | You are wearing earphones connected to a mobile while being in space without a spacesuit, let's imagine you would not freeze to death or suffocate in seconds. Would you be able to hear any sound at all, or feel any vibrations in your ears? | [
"It's true that there is no medium of heat transfer, but your body still cools down by radiating energy into space. A quick, crude calculation using ",
"this",
" and ",
"this",
" suggests that in space you lose energy at a rate of about 1kW (assuming you're in the dark). The conductive loss in ice water wou... | [
"At the same time, you might be burned to death where exposed to the sunlight. Then again, you would be evaporating water from your body, thus cooling off.",
"I would like to know what the most probable causes of death would be. Would you freeze or burn or dry to death?"
] | [
"You ",
" freeze to death in space if the sun isn't visible (as in, being occluded by the Earth) -- heat can get transferred via radiation away from you.",
"This assumes you're in a pressurized space suit that has no heating.",
"Otherwise you'd die from the low pressure and dry up like beef jerky due to the f... |
[
"So I know glass is not actually a super-viscous liquid, but are there any liquids that actually exhibit this property?"
] | [
false
] | It doesn't necessarily have to be over the course of centuries, but what are some liquids that will hold a "solid" shape for a short period of time? | [
"OP knows that it isn't a super-viscous liquid and clearly states so in the title of the post."
] | [
"Pitch (tar) ",
"Source"
] | [
"Some forms of asphalt (much like pitch) appear to be solid but have viscosity. Our materials professor took a chunk of asphalt at room temperature broke it with a hammer into shards then put the shards in a pan on top of a mushroom shaped piece of metal (think a cake stand but about 2 inches tall and 4inches in ... |
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