Since we measure nuclear warhead yields in terms of tonnes of TNT, would detonating an equivalent amount of TNT actually produce a similar explosion in terms of size, temperature, blast wave etc?

---

• Since we measure nuclear warhead yields in terms of tonnes of TNT, would detonating an equivalent amount of TNT actually produce a similar explosion in terms of size, temperature, blast wave etc?
• Why do images from scanning electron microscopes all have this grainy effect?
• If you were to sky-dive in the rain, would water hit your stomach, back, or both?
• How doesn't the large hadron collider get damaged by its tests?
• Rotational speed and deformed of nuclei?
• What is the Link Between the Primary Auditory Cortex and Motor Cortex?
• Can donated organs be re-donated?
• If I make a cup of coffee in my Keurig, then make another cup using the same grounds, roughly how much caffeine is in the second cup?
• What is happening in our brain when we can’t recall something, then we suddenly remember after a few seconds of trying?
• How do we know what makes up the center of the world?
• Why does mitochondrial DNA only come from the mother?
• What causes the values for nuclear spin for combinations of protons and neutrons?
• What was it like when cosmic background radiation passed the visual spectrum?
• Could a really long straw going into space drain the oceans?
• If an aircrafts cabin is pressurized, why can people feel a significant change in air pressure in the ear drum during lift off and landing?
• Have new craters on the moon been observed?
• When light is polarised where does the magnetic field of the EM wave go?
• How much power is needed to get signals to the mars rover, and/or further places in space?
• Why is the electromagnetic spectrum classified the way it is?
• How do they predict the expiration date on food such as milk, bread, etc?
• Solids precipitate out of solution, but what do gasses do?
• What is it about merged species (Mules, Ligers) that makes them sterile?

Since we measure nuclear warhead yields in terms of tonnes of TNT, would detonating an equivalent amount of TNT actually produce a similar explosion in terms of size, temperature, blast wave etc? Posted: 03 Dec 2018 01:07 PM PST Follow up question, how big would a Tzar Bomba size pile of TNT be? (50 megatons) submitted by /u/OverRetaliation [link] [comments]

Why do images from scanning electron microscopes all have this grainy effect? Posted: 04 Dec 2018 05:14 AM PST I was watching this video https://www.youtube.com/watch?v=j6B-HYsvkvo and noticed that the images produced by electron microscopes seem to have this grain or texture consistent amongst all of them, is there a specific reason for this? Thanks! submitted by /u/eekelmo_ [link] [comments]

If you were to sky-dive in the rain, would water hit your stomach, back, or both? Posted: 04 Dec 2018 07:16 AM PST submitted by /u/LEGSwhodoyoustandfor [link] [comments]

How doesn't the large hadron collider get damaged by its tests? Posted: 04 Dec 2018 03:43 AM PST Colliding particles produces (transforms) a lot of energy, so how doesn't that damage all the very delicate sensors put in place? submitted by /u/dablusniper [link] [comments]

Rotational speed and deformed of nuclei? Posted: 03 Dec 2018 11:44 PM PST Does the rotational speed of a nucleus affect it's deformation? As in when an unstable superheavy element is noted to have a deformed to hyperdeformed nucleus, is that a reflection of it's rotational speed? And if not, why does the deformation only occur on a rotational plane, and not just result in an instantaneous decay or a more sparsely packed nucleus (deformation of 3 axes instead of elliptical deformation on 2 axes)? Can a stable nucleus become deformed without changing proton or neutron count, or adding a neutron to a nucleus to induce deformation? Can this impact stability? Sorry about the run-on questions, thanks in advance! submitted by /u/aaronnium [link] [comments]

What is the Link Between the Primary Auditory Cortex and Motor Cortex? Posted: 03 Dec 2018 06:01 PM PST It is kinda hard to ask this question in a single sentence, but you know how some animals' ears move when they detect particular/loud noises? From all the models I've encountered of human motor cortex (motor homonculus), there is no encoding for ear movements. Obviously some animals can perform isolated ear movement, presumably to hear "better". I was wondering if these animals have a special pathway between the primary auditory cortex and the ear-encoding motor cortex, a bit like how the language cortex in humans is closely connected to mouth/lips/pharynx motor and premotor cortex. submitted by /u/merdouille44 [link] [comments]

Can donated organs be re-donated? Posted: 03 Dec 2018 10:25 AM PST Once the person receiving the transplant passes, can those same organs be donated again if that person signs up as an organ donor? submitted by /u/Firch88 [link] [comments]

If I make a cup of coffee in my Keurig, then make another cup using the same grounds, roughly how much caffeine is in the second cup? Posted: 03 Dec 2018 03:51 PM PST Assuming two 8oz cups, for argument's sake, using 10-12g ground coffee. Not looking for exact numbers, but even just a percentage would be super helpful :) Just curious about how efficient the first extraction is. submitted by /u/DrSwol [link] [comments]

What is happening in our brain when we can’t recall something, then we suddenly remember after a few seconds of trying? Posted: 03 Dec 2018 10:44 AM PST submitted by /u/BadassGhost [link] [comments]

How do we know what makes up the center of the world? Posted: 03 Dec 2018 05:49 PM PST submitted by /u/Ogieogilthorpe17 [link] [comments]

Why does mitochondrial DNA only come from the mother? Posted: 03 Dec 2018 12:14 PM PST Why would there not be at least some mitochondrial DNA from the father, considering the fact that sperm cells have a good deal of mitochondria in them? submitted by /u/Inkboy13 [link] [comments]

What causes the values for nuclear spin for combinations of protons and neutrons? Posted: 03 Dec 2018 03:56 PM PST So I've been reading about how the nuclear spin is zero if there are an even number of protons and neutrons, an integer if there are an odd number of protons and neutrons, a half integer for all other combinations. Is there a reason or some formula behind this? I'm assuming it has to do something with the interaction between the quarks and gluons, but I can't find any explanation of it. submitted by /u/theajadk [link] [comments]

What was it like when cosmic background radiation passed the visual spectrum? Posted: 03 Dec 2018 07:36 AM PST If cosmic background radiation has been 'cooling down' (or stretching out /slowing down) from gamma rays at the beginning of time to xrays/tv static now, roughly how long ago did it go through the visual range? What would that have been like? What about thermal infrared? Did everything get hotter for a while? submitted by /u/sumner980 [link] [comments]

Could a really long straw going into space drain the oceans? Posted: 03 Dec 2018 08:27 AM PST My friend is convinced that if you put one end of a straw in the ocean, and the other into the vacuum of space, that it would drain the ocean. He thinks capillary action, space being a vacuum, and siphoning, would be able to drain the ocean into space. Am I wrong saying this wouldn't work, at least in any reasonable time frame (Quadrillions of years)? submitted by /u/TheBupherNinja [link] [comments]

If an aircrafts cabin is pressurized, why can people feel a significant change in air pressure in the ear drum during lift off and landing? Posted: 03 Dec 2018 08:53 AM PST submitted by /u/martmannen [link] [comments]

Have new craters on the moon been observed? Posted: 03 Dec 2018 11:30 AM PST Or all that we see are pre existing ones? Do we know how to date the existing craters ? submitted by /u/pier4r [link] [comments]

When light is polarised where does the magnetic field of the EM wave go? Posted: 03 Dec 2018 11:45 AM PST It's logical that light is simply no longer EM wave if there are no 2 components of electric and magnetic field, but books always illustrate polarised light as it is only one field after polariser. So where does it go then? submitted by /u/bracaco [link] [comments]

How much power is needed to get signals to the mars rover, and/or further places in space? Posted: 03 Dec 2018 02:29 PM PST At my basic understanding, the waves would get weaker the further they travel, so how do they get the signals out there, and does it require crazy amounts of power, or is it really not that hard (relatively speaking). submitted by /u/andrewsmd87 [link] [comments]

Why is the electromagnetic spectrum classified the way it is? Posted: 03 Dec 2018 02:05 PM PST Is there any significance to the names we give to different parts of the electromagnetic spectrum? Or are those classes based on something which distinguishes these classes? submitted by /u/BaumDude [link] [comments]

How do they predict the expiration date on food such as milk, bread, etc? Posted: 03 Dec 2018 01:43 PM PST submitted by /u/JustLookinggstuff [link] [comments]

Solids precipitate out of solution, but what do gasses do? Posted: 03 Dec 2018 09:50 AM PST To be precise, what's the word for a gas going from an aqueous state to a gas state? submitted by /u/dablusniper [link] [comments]

What is it about merged species (Mules, Ligers) that makes them sterile? Posted: 03 Dec 2018 05:47 AM PST And are there examples of seperate species merging together? submitted by /u/BadHairDayToday [link] [comments]

You are subscribed to email updates from AskScience: Got Questions? Get Answers.. To stop receiving these emails, you may unsubscribe now.	Email delivery powered by Google
Google, 1600 Amphitheatre Parkway, Mountain View, CA 94043, United States

What actually determines the half-time of a radioactive isotope?

---

• What actually determines the half-time of a radioactive isotope?
• What was the Amazon like when the Sahara was still green?
• Can bugs feel pain?
• how does Van der Waals force play a part in adsorption of gas on solid surface?
• How do complex mutations happen through evolution?
• How does NH4+ interfere with Oxidative Phosphorylation?
• Optics question: What are the lines of light in clear water called?
• Why do people get morning breath?
• What would happen gravitationally if Earth where surrounded by a hollow sphere?
• What does "thinness" or "thickness" of air imply and how does it happen and change?
• Does the southern hemisphere see different stars to the northern hemisphere?
• Why is quantum entanglement so important to quantum computing?
• What makes one particular material good at dampening sound versus another material?
• How will the redefinition of a Kilogram affect the Atomic Masses/Moles of the periodic table?
• Why do obstructions occur more frequently in the coronary arteries than other vessels throughout the body?
• How do heart rate measurement apps manage to do their job by just using your phone's camera and flash?
• Why do increased insulin levels aid in the absorption of creatine monohydrate?
• When you're ill why does the body keep trying to throw up even if our stomach is empty? Can it not tell?
• If a woman is born with all her eggs at birth, how can her age at conception influence Down’s syndrome?
• How does the brain store/retrieve language?

What actually determines the half-time of a radioactive isotope? Posted: 03 Dec 2018 03:45 AM PST Do we actually know what determines the half-time of a radioactive isotope? I tried to ask my natural science teacher this question, but he could not answer it. Why is it that the half-time of for an example Radium-226 is 1600 years, while the half-time for Uranium-238 is 4.5 billion years? Do we actually know the factors that makes the half-time of a specific isotope? Or is this just a "known unknown" in natural science? submitted by /u/skadabombom [link] [comments]

What was the Amazon like when the Sahara was still green? Posted: 02 Dec 2018 09:12 AM PST The sandstorms from the Sahara are cited as a contributing factor to how big the Amazon is because of all the mineral nutrients that are carried in the sand to Amazon soil (and North American soil as well). Well what was the region like a few thousand years ago when those sandstorms weren't happening? Was it it's own dessert? Or did the Amazon river support a river plain like the Mississippi River basin in the US and Canada? submitted by /u/Rancerle [link] [comments]

Can bugs feel pain? Posted: 02 Dec 2018 10:43 AM PST I once read in one of those CWF Wild magazines years ago that bugs cant feel pain because their nervous system is too small. Does anyone know if this is true, and if so what causes it? submitted by /u/StormShadow921 [link] [comments]

how does Van der Waals force play a part in adsorption of gas on solid surface? Posted: 03 Dec 2018 05:28 AM PST submitted by /u/eikoraid [link] [comments]

How do complex mutations happen through evolution? Posted: 02 Dec 2018 11:15 AM PST How do extremely complex organs come to exist through mutations? I don't think that a single mutation could cause something as complex as eyes to exist but it's also hard to believe that a small mutation like the beginning of eyes would be valuable enough for natural selection to create a large enough population of it for it to mutate again. submitted by /u/AtlasCommunity [link] [comments]

How does NH4+ interfere with Oxidative Phosphorylation? Posted: 02 Dec 2018 09:09 PM PST submitted by /u/aiden_pierce77 [link] [comments]

Optics question: What are the lines of light in clear water called? Posted: 02 Dec 2018 12:58 PM PST For instance, the lines of light that are reflected in this photograph. ​ [Imgur](https://i.imgur.com/KGeDZR5.jpg) submitted by /u/Psidius [link] [comments]

Why do people get morning breath? Posted: 02 Dec 2018 05:23 PM PST Also, why don't we get it throughout the day? submitted by /u/Bren0829 [link] [comments]

What would happen gravitationally if Earth where surrounded by a hollow sphere? Posted: 02 Dec 2018 02:42 PM PST Based on Newtonian Gravity/Newton's Shell Theorem the gravity caused by they sphere would be zero inside, so would Earth just drift within the sphere? submitted by /u/cilantno [link] [comments]

What does "thinness" or "thickness" of air imply and how does it happen and change? Posted: 02 Dec 2018 10:25 AM PST submitted by /u/olenus [link] [comments]

Does the southern hemisphere see different stars to the northern hemisphere? Posted: 02 Dec 2018 01:19 PM PST submitted by /u/John_Glames [link] [comments]

Why is quantum entanglement so important to quantum computing? Posted: 02 Dec 2018 10:05 AM PST I understand that superposition allows for multiple operations to go on at once, and I understand quantum entanglement. I keep reading that entanglement is involved in quantum computing but I cant find a definitive answer as to how it actually helps. Thanks in advance for your help :) submitted by /u/prongs392 [link] [comments]

What makes one particular material good at dampening sound versus another material? Posted: 02 Dec 2018 10:13 AM PST I'm sure it's more than a function of material density. Is there a metric for a materials ability to convert acoustic waves to phonons which permit photonic emission? submitted by /u/DrLetric [link] [comments]

How will the redefinition of a Kilogram affect the Atomic Masses/Moles of the periodic table? Posted: 02 Dec 2018 10:01 AM PST submitted by /u/TERMONATORKILLER [link] [comments]

Why do obstructions occur more frequently in the coronary arteries than other vessels throughout the body? Posted: 02 Dec 2018 09:41 AM PST It is my understanding that a heart attack is caused by plaque build up in the coronary arteries. Correct? Why do we never hear about obstructions in other vessels? What is it about the vessels of the heart that make them more prone to obstruction? submitted by /u/IsntItNeat [link] [comments]

How do heart rate measurement apps manage to do their job by just using your phone's camera and flash? Posted: 02 Dec 2018 05:35 AM PST submitted by /u/FD_GO [link] [comments]

Why do increased insulin levels aid in the absorption of creatine monohydrate? Posted: 02 Dec 2018 12:29 PM PST ​ submitted by /u/Donald-Trumps-Hair [link] [comments]

When you're ill why does the body keep trying to throw up even if our stomach is empty? Can it not tell? Posted: 02 Dec 2018 03:39 AM PST Very recently I was ill and being sick every couple hours. But after a couple times I was just dry heaving as I had nothing left in my stomach. I'm wondering why my body couldn't tell my stomach was empty and kept trying in vain to throw something up. submitted by /u/Im_a_human_man [link] [comments]

If a woman is born with all her eggs at birth, how can her age at conception influence Down’s syndrome? Posted: 02 Dec 2018 08:16 AM PST Down's syndrome is trisomy, a chromosomal separation error in Meiosis. Because it is more common in older mothers I imagine the trisomy comes in the egg. But if eggs are ready at birth, how do the eggs with trisomy come later in life? Are the egg cells "set aside and ready" at birth but actually experience Meiosis close to ovulation? submitted by /u/diogenes_shadow [link] [comments]

How does the brain store/retrieve language? Posted: 02 Dec 2018 08:32 AM PST submitted by /u/Kubiamine [link] [comments]

You are subscribed to email updates from AskScience: Got Questions? Get Answers.. To stop receiving these emails, you may unsubscribe now.	Email delivery powered by Google
Google, 1600 Amphitheatre Parkway, Mountain View, CA 94043, United States

If microevolution is evident given the way microbes evolve in response to antiobiotics+vaccines, wouldn't microevolution also be present in our own microbiome, serving as observable evidence of evolution in humans+other animals?

---

• If microevolution is evident given the way microbes evolve in response to antiobiotics+vaccines, wouldn't microevolution also be present in our own microbiome, serving as observable evidence of evolution in humans+other animals?
• Is Quantum Mechanics Really Random?
• Does gamma radiation excite nuclei?
• How do we measure eccentricity in the orbits of stars around galactic centers?
• What is the default state of the muscles that are responsible for closing your eyes?
• Are animals able to count and do they have any idea of numbers?
• If we ever have the opportunity to mine other planets like Mars, will we discover similar gems, crystals and precious metals like we do on Earth?
• Does classical thermodynamics hold up at relativistic speeds?
• Is the perception of heat linear or nonlinear?
• How do satellites know when they're close to one another?
• Do reptiles and bugs fart?
• Does Cancer continue spreading in a dead body?
• What would the day/night cycle be like on a NON-tidally locked moon?
• How are the IV curves of solar cells determined?
• If breaking the speed barrier causes a sonic boom, then why isn’t light or space radiation constantly causing booms?
• Why and how do small fishes (like goldfish) overfeed themselves to their death?
• What causes mosquito and other bug bites to swell up?
• How do you control the torque curve of an electric motor?
• What happens at the cellular level when leaves turn from green to other colors in autumn?

If microevolution is evident given the way microbes evolve in response to antiobiotics+vaccines, wouldn't microevolution also be present in our own microbiome, serving as observable evidence of evolution in humans+other animals? Posted: 02 Dec 2018 03:34 AM PST TL;DR - listening to microbiology podcast episode, microbiologist+podcaster mentioned [bad] microbes being originally believed to be supernatural/demons [with no knowledge of good microbes, or microbes at all], I recalled that microevolution is observable, people deny macroevolution for lack of contemporary observability, supernatural belief is generally pitted against macro scale evolution (stating that we "can't observe" it), our body has a microbiome which contributes to certain fundamental biological aspects/functions,etc., this sounds to me like potential observable evidence of evolution in humans+other animals. • I was just thinking about this listening to the microbiology episode of the Ologies podcast and it got me thinking about our understanding of evolution starting at the micro scale in relation to supernatural beliefs. Bare with me. Specifically, I was thinking about how she mentioned that the English word "bug" (in reference to bacteria/microbial bugs) comes from a Welsh word for ghost or evil spirit. It reminded me of a few weeks ago when I was listening to Joe Rogan speaking to someone (I think it was Elon Musk) and they were mentioning how we have the problem of making new antibiotics and vaccines every year because microbial bugs continue to adapt to the treatments and evolve into newer, stronger bugs. I.e., some of them "superbugs". Edit: the microbiologist she was interviewing also spoke about how changing the gut bacteria in mice (among other animals) made them behave differently. Would that possibly indicate something in relation to humans? Edit 2: Also was reminded that up to 90% of our serotonin is produced by gut bacteria, so the state of our microbiome obviously plays an integral role in our general state of being and our behavior. An example I think about all the time, for those who don't know, is saying the phrase "bless you" or "God bless you" after a person sneezes which stems from people once believing that sneezing was our soul getting rid of evil spirits/demons in our body, or another origin stating that a Pope thought people were dying (or something of the likes) when they coughed and sneezed so this short blessing would protect them. And centuries later, even tho we understand allergies and inhaling dust and mucus production and the common cold, etc. is not demons or deadly, most people still say "[God] bless you" after a person sneezes. And if anyone here happens to have played God of War you might remember when Sindri tells you that Freya discovered "little beasties" (microbes/bacteria) on everything lol, and said they were responsible for human sickness. Just a funny reference to how people once did believe microbes and their effects on us was a supernatural matter. My point in emphasizing our understanding, or lackthereof, during that part of history is that supernatural beliefs are generally pitted against biological evolution. But the irony is that what once was considered a supernatural phenomenon by those fundamentally against evolution, now seems to serve as clear evidence of evolution. It seems like people subconsciously think less objectively, or less overall, about the matter or just deny whatever they're told, but somehow many people will still consciously accept what we've learned from the matter. submitted by /u/fuckingblackmale [link] [comments]

Is Quantum Mechanics Really Random? Posted: 01 Dec 2018 09:51 PM PST Really dumb it down for me, I don't know much about Quantum Mechanics. I have heard that quantum mechanics deals with randomness, and am trying to understand the implications for our understanding of the universe as deterministic. First of all, what do scientists mean when they say random? Sometimes scientists use words differently than most people do. Do they mean random in the same way throwing a dice is 'random'? Where the event has a cause and the outcome could theoretically be predicted, but since we don't have enough information to predict the outcome we call it random. Or do they mean random in the sense that it could literally be anything and is impossible to predict? I have heard that scientists can at least determine probabilities (of the location of a particle I think), if you can determine the likelihood of something doesn't that imply that something is influencing the outcome (not random)? Could these seemingly random events simply be something scientists don't understand fully yet? Could there be something causing these events and determining their outcome? If these events are truly random, how do random events at the quantum level translate into what appears to be a deterministic universe? Science essentially assumes a deterministic universe, that reality has laws that can be understood, and this assumption has held up pretty well. submitted by /u/archon325 [link] [comments]

Does gamma radiation excite nuclei? Posted: 02 Dec 2018 05:58 AM PST Since exicted nuclei emit gamma radiation to get back into their ground state, can they also absorb (certain wavelenghts of) gamma radiation? Going further than the general question above: Could gamma radition be used to deliberatly excite a nuclei, possibly leading to fission (or induce alpha/beta decay in fitting isotopes) or fusion of several, nuclei already under high pressure/temperature? Would a (hypothetical) gamma ray laser be useful to create fusion on demand, possibly even a fusion power plant? (And while I am at it: Is there recent research about those hypothetical gamma lasers? From googling around all I could find articles indicating there's some occasional research going on for the last 60 decades, but nothing too promising). submitted by /u/TheRealStardragon [link] [comments]

How do we measure eccentricity in the orbits of stars around galactic centers? Posted: 02 Dec 2018 07:32 AM PST One of the things that led people to assume that we need "dark matter" is that the orbits of stars around the galactic center of mass is "too fast" as you move out from the center. How do we differentiate between stars that are in circular orbits that are too fast for the known mass distribution from stars in more eccentric orbits that happen to be in a lower portion of their orbit right now and are moving faster as a result? submitted by /u/froginthelibrary [link] [comments]

What is the default state of the muscles that are responsible for closing your eyes? Posted: 01 Dec 2018 03:29 PM PST If you were to turn 'off' the muscles that open/close your eyelids, would your eyes stay open or closed? I know that the majority of the time when people die, their eyes stay open, but it is possible to close the eyes and have them remain closed. When we go to sleep, we almost feel like our eyes are wanting to naturally close, but when we're awake, it's very easy to keep them open, so would that mean that we're using our eyelid muscles constantly when we are awake? Edit: grammar submitted by /u/Willdrow [link] [comments]

Are animals able to count and do they have any idea of numbers? Posted: 01 Dec 2018 04:27 PM PST submitted by /u/Delusional_highs [link] [comments]

If we ever have the opportunity to mine other planets like Mars, will we discover similar gems, crystals and precious metals like we do on Earth? Posted: 01 Dec 2018 06:47 PM PST submitted by /u/RobbKyro [link] [comments]

Does classical thermodynamics hold up at relativistic speeds? Posted: 01 Dec 2018 10:39 AM PST Hi there, undergrad materials engineer here. I was wondering if classical thermodynamics would hold up for matter traveling at relativistic speeds. The idea behind this question started with a friend and I discussing accretion discs of black holes, and wondering how to model diffusion/mixing processes as one nears the event horizon. Questions like how would the chemical potential for adding a proton to the accretion disk change if the matter of the disk were travelling at .9c and the proton was travelling at v << c verses v =.9c? submitted by /u/Phalcone42 [link] [comments]

Is the perception of heat linear or nonlinear? Posted: 01 Dec 2018 10:11 AM PST I have always felt that when microwaving food, it quickly transitions from lukewarm to way-too-hot. This makes me wonder, is our perception of heat linear or nonlinear? For example, if the temperature of my soup goes up by 10%, does my perception of the hotness go up by 10% or some other factor? The possibility reminds me of how we process hearing, which is more logarithmic. submitted by /u/eternusvia [link] [comments]

How do satellites know when they're close to one another? Posted: 01 Dec 2018 05:17 PM PST A couple of months ago it was announced that a Russian satallite, the Luch-Olymp had come suspiciously close to a French satellite the Athena-Fidus. According to many sources the Russian satellite came within 10km of the French one, how was this known? Does each satellite have sensors to see if other satellites are near to it? submitted by /u/HunTer_286 [link] [comments]

Do reptiles and bugs fart? Posted: 01 Dec 2018 10:02 AM PST For context, this was a thought because of the recent news of a spider species that feeds milk to its young. Someone suggested it could be a environmental boon if we had spider milk versus cow milk. I doubt any of that is feasible but it got me wondering if non-mammals toot? submitted by /u/dagmx [link] [comments]

Does Cancer continue spreading in a dead body? Posted: 01 Dec 2018 01:23 PM PST Does cancer need a living host in order for it to spread, or can it continue to spread even after the person dies? submitted by /u/brilliantlyabby [link] [comments]

What would the day/night cycle be like on a NON-tidally locked moon? Posted: 01 Dec 2018 05:56 PM PST It seems to me that at least half the time it would be night time everywhere on the surface as the moon moves behind its planet relative to the sun, but the other half of the time would be a more typical day/night cycle as viewed from the surface. I'm having a hard time confirming this just by Googling and using Wikipedia, as most of the major moons I can think of are tidally locked. submitted by /u/absolute_future [link] [comments]

How are the IV curves of solar cells determined? Posted: 01 Dec 2018 05:46 PM PST Hi all, I'm having a hard time understanding the IV curve of a solar cell. All the sources that I have consulted are saying that it is literally the IV curve of a regular PN junction shifted downwards. The amount of shift depends on the amount of illumination. However what I'm confused about is whether or not we bias the solar cell. E.g. here is a IV curve of a regular PN diode. The "forward bias" region in the image is due to the experimenter hooking up a voltage supply to the diode and measuring the current as a function of the value of the external voltage supply. The "reverse bias" region in the image is similarly due to reversing the polarity of the external voltage source and measuring the current. Now, is this how the IV curves for a solar cell is also produced? I.e. do we apply an external voltage source, in addition to an illumination source, to get the IV curve of a solar cell? A related question is: are solar cells operated under a forward bias? I know that in order for a solar cell to produce power, we must look at the 4th quadrant of its IV curve, since in this case the passive sign convention dictates that power is being generated. Here is the IV curve of a solar cell. While the cell is being illuminated, it shifts downwards, and a part of the illuminated IV curve passes through the 4th quadrant of the graph. So, in order for the solar cell to produce power, it must be operating in the 4th quadrant. However, the voltage in the 4th quadrant is positive. I'm not sure how to interpret this voltage. Is this voltage the voltage that is being supplied to the solar cell externally? I.e. similar to applying an external voltage to a PN diode to record its IV characteristics? So does this mean that the solar cell (e.g. a solar panel that is being used to power up a house) is operated under a forward bias? Different sources say different things. This source suggests that solar cells are not operated under ANY bias. In this source, different answerers give different responses. Maybe I'm not understanding the concept of biasing? Maybe biasing means different things when used in the context of PN diodes and BJT transistors vs. a solar cell? Are solar cells operated under a bias? What does "bias" mean in this case? Does it mean simply connecting an external voltage source to the solar cell? Or does it mean something else? Thanks for your help guys! :) submitted by /u/DoctorKokktor [link] [comments]

If breaking the speed barrier causes a sonic boom, then why isn’t light or space radiation constantly causing booms? Posted: 01 Dec 2018 01:36 PM PST submitted by /u/Fromfame [link] [comments]

Why and how do small fishes (like goldfish) overfeed themselves to their death? Posted: 01 Dec 2018 11:24 AM PST submitted by /u/consistent_escape [link] [comments]

What causes mosquito and other bug bites to swell up? Posted: 01 Dec 2018 04:27 PM PST First post here. I'm just curious about what exactly causes the swelling and itchiness when someone is bitten by a spider or insect, and couldn't find an explicit answer online. submitted by /u/ThoseFreeFries [link] [comments]

How do you control the torque curve of an electric motor? Posted: 01 Dec 2018 09:28 AM PST Edit: To clarify, I'm curious if torque/power curves for electric motors can be tuned similar to torque/power curves for internal combustion engines and either how or why not. Thanks! submitted by /u/T2QTIW31hmtGbNsq [link] [comments]

What happens at the cellular level when leaves turn from green to other colors in autumn? Posted: 01 Dec 2018 09:18 AM PST Leaves turning is essentially the death of the leaf right? So if chloroplasts reflect green light, do these dying chloroplasts reflect the yellow, red, orange, brown colors we see? submitted by /u/bencargo30102 [link] [comments]

You are subscribed to email updates from AskScience: Got Questions? Get Answers.. To stop receiving these emails, you may unsubscribe now.	Email delivery powered by Google
Google, 1600 Amphitheatre Parkway, Mountain View, CA 94043, United States