Pages

Sunday, August 19, 2018

Do plants receive a measureable amount of energy from starlight other than the Sun, versus if they were in total darkness?

Do plants receive a measureable amount of energy from starlight other than the Sun, versus if they were in total darkness?

Do plants receive a measureable amount of energy from starlight other than the Sun, versus if they were in total darkness?

Posted: 19 Aug 2018 05:57 AM PDT

Sub-question: is there measureable phototropism behavior towards starlight, if any?

submitted by /u/Letchworth
[link] [comments]

Do magnetic and/or electric field have any influence on time and space?

Posted: 19 Aug 2018 06:22 AM PDT

According to Einstein, gravity has influence on space and time. Does magnetic field have influence on time and space? Does electric field have influence on time and space?

submitted by /u/timetravel369
[link] [comments]

What's the difference between being knocked out and being unconcscious when you sleep?

Posted: 19 Aug 2018 07:15 AM PDT

How was the age at which the universe became transparent calculated?

Posted: 19 Aug 2018 01:01 AM PDT

I'd curious about the most accurate primary source regarding such data & calculations, thanks.

submitted by /u/Sitervain
[link] [comments]

Why is the human heart located on our left side? Shouldn’t it be as centrally located possible?

Posted: 19 Aug 2018 05:07 AM PDT

How much of a problem is space debris for the ISS and shuttles?

Posted: 18 Aug 2018 03:08 PM PDT

Do large Earthquakes risk setting off other nearby faultlines?

Posted: 18 Aug 2018 06:47 PM PDT

For example, when the Cascadia Subduction Zone next goes, it's supposed to cause a truly massive earthquake... Will this increase the likelihood of a major earthquake in California? Or if there is a major Earthquake in Fiji, like just happened, does that impact the opposite side of the tectonic plate? Or am Imagining the plates as much too rigid?

submitted by /u/multiple_iterations
[link] [comments]

How are old buildings built with asbestos demolished safely?

Posted: 18 Aug 2018 04:58 PM PDT

What is going on when you submerge a ball deep into a pool and then it jumps back in a random direction? Is there any way to predict the trajectory?

Posted: 18 Aug 2018 07:11 AM PDT

What chemical compound contributes to the classic "campfire smell?"

Posted: 18 Aug 2018 07:58 AM PDT

Referring to the smell that clothes sometimes take on when they're exposed to lots of campfire smoke.

submitted by /u/TimAnEnchanter
[link] [comments]

Why are human eyeballs white?

Posted: 18 Aug 2018 07:22 AM PDT

Is it possible to have them black or some other color? (maybe for a fantastical humanoid if not for RL humans?)

submitted by /u/AoiMizune
[link] [comments]

What is the status of the search for room temperature superconductors?

Posted: 18 Aug 2018 11:18 AM PDT

I know a few years ago there were some relatively promising advances using cuprates. I read something about gold and silver having room temperature superconductivity recently, but that seems implausible based on my experience with materials, and the noise patterns observed in their testing. What is currently the most promising path, and have there been much in advances since they reproduced a superconductor at 203 kelvin?

submitted by /u/GyrokCarns
[link] [comments]

Why would animals share self-harming information?

Posted: 18 Aug 2018 08:09 AM PDT

I read that dogs have anal glands that release smells which give information to other dogs about their health. So other dogs can decide if they would want to make acquaintance but wouldn't natural selection make it so that all dogs would give out 'good' smells even if they were unhealthy just to get a chance to reproduce? Is there an evolutionary advantage to sharing honest information that reduces the individual's opportunity to pass on his genes? There must be similar examples in other animals as well.

submitted by /u/Collateral_awesome
[link] [comments]

If the earth rotated at the same speed but in the opposite direction, how long would a day be?

Posted: 18 Aug 2018 08:36 AM PDT

How do electron 'standing waves' relate to the probability density cloud?

Posted: 18 Aug 2018 07:33 AM PDT

Let me try to explain what I've sort of understood thus far:

  1. In atomic spectra, we observe that instead of a continuous spectrum of light, a line spectrum is produced instead. This indicates some sort of discrete energy quantities that electrons can possess, such that photons of specific frequencies can be emitted to 'form' the line spectrum. Bohr's model sort of explains this, yet cannot account for the electromagnetic radiation of the electrons.
  2. de Broglie then suggests that perhaps electrons exist as circular standing waves, of which wavelength can only exist as integers of the orbital circumference. (If not, the electron cannot exist as it would interfere with itself). This explains the discrete energy levels, as the electrons can only absorb/release the exact amount of energy it requires to move from one 'harmonic' to another to form complete standing waves.

My first question might be a little dumb-sounding, but how does de Broglie's model account for the electromagnetic radiation of the electrons? I'm pretty sure the electrons still release electromagnetic radiation, but how does the 'standing wave' model make sense for how the electrons do not fall into the nucleus of the atom?

My second question at this point is, what are these 'standing waves'? I'm trying my best to think of these standing waves outside of its classical interpretation, but its getting kinda fuzzy in my mind. Are they mapping out the orbitals / probability clouds? (Which if I recall correctly, is described by the wave function as given by Schrodinger's equation.)

Please do correct me if there are any discrepancies in what I've typed out so far. Thank you for any help given.

submitted by /u/Xeldith
[link] [comments]

Can regenerative animals keep regrowing the same limbs over and over without any loss?

Posted: 18 Aug 2018 02:52 AM PDT

For example, salamanders can regrow limbs/tails. What if that same limb gets chopped off again or multiple times, will it regrow back again perfectly or are there diminishing returns each regrowth?

submitted by /u/ram-ok
[link] [comments]

[Physics] Can relativistic physics be adjusted to allow for switching between accelerating and non-accelerating frames of reference?

Posted: 18 Aug 2018 09:13 AM PDT

For example: say a spaceship accelerates away from a stationary observer. What would the observer's "world-line" look like from the spaceship's perspective and what would the spacetime diagram look like?

submitted by /u/Husky2490
[link] [comments]

Why does driving by a parked car on the road make a different sound than driving by the ground or a sidewalk?

Posted: 18 Aug 2018 06:43 AM PDT
vào lúc No comments:

Saturday, August 18, 2018

The freezing point of carbon dioxide is -78.5C, while the coldest recorded air temperature on Earth has been as low as -92C, does this mean that it can/would snow carbon dioxide at these temperatures?

The freezing point of carbon dioxide is -78.5C, while the coldest recorded air temperature on Earth has been as low as -92C, does this mean that it can/would snow carbon dioxide at these temperatures?

The freezing point of carbon dioxide is -78.5C, while the coldest recorded air temperature on Earth has been as low as -92C, does this mean that it can/would snow carbon dioxide at these temperatures?

Posted: 18 Aug 2018 05:03 AM PDT

For context, the lowest temperature ever recorded on earth was apparently -133.6F (-92C) by satellite in Antarctica. The lowest confirmed air temperature on the ground was -129F (-89C). Wiki link to sources.

So it seems that it's already possible for air temperatures to fall below the freezing point of carbon dioxide, so in these cases, would atmospheric CO2 have been freezing and snowing down at these times?

Thanks for any input!

submitted by /u/FloatingArk54
[link] [comments]

How close could a machine get to the Sun?

Posted: 17 Aug 2018 08:31 AM PDT

I was reading about the Parker probe and it's amazing just how close that thing is going to get to the sun; but it of course made me wonder how much closer we could get. The Parker probe basically uses a big oriented shield to protect itself, and behind the shield it's more a normal spacecraft.

Is it conceivable that anything could be constructed that could survive passing through the corona? It seems stuff must be whipping around like crazy in there, plus the insane temperatures. To my knowledge the highest known melting points are in the thousands of degrees, but I figure there is also some kind of blast force or something going on there.

Edit and if the corona is so easy, can you conceive of a spacecraft passing through the photosphere and surviving?

Not that it is possible with any known technology, but is it even physically conceivable that something could survive a close approach towards the surface of the sun? What would be necessary (special materials? some kind of super-magnet?)?

edit 2 Thanks all for the entertaining and informative comments! I will let you all know when my machine is completed and ready for launch.

submitted by /u/aggasalk
[link] [comments]

How does nuclear fusion produce energy?

Posted: 18 Aug 2018 03:12 AM PDT

From where does energy where two hydrogen atoms produce one helium atom come from?

How much mass is actually lost in the process?

Giving that helium atom is almost as four times heavier than hydrogen atom how is this even possible?

submitted by /u/Let_me_tug_it
[link] [comments]

How are the atomic masses of the elements measured precisely?

Posted: 17 Aug 2018 02:08 PM PDT

I am an ib physics student and I was recently going through an unit on energy production. One of the topics was about fission reactions, in which a question involved the isotopic mass of Uranium-235 (and its reaction in reactors). I noticed that the mass was given all the way out to 6 significant figures. I looked up a reference table and it is reported out to 10 digits with a relative uncertainty of 8.5x10^-7% (!!). In the same table, I also see elements like Oxygen-16 (13 digits) or Sodium (12 digits). This is extremely precise. I was wondering what the process behind the measurement was and what sorts of instruments are used?

Also, as a follow up question. When and why are such precise measurements needed? Are there practical differences between this and slightly less precise measurements or are they just because we can? I assume its related to particle physics/quantum mechanics.

submitted by /u/backman_10
[link] [comments]

What exactly is spin in quantum mechanics?

Posted: 17 Aug 2018 06:24 AM PDT

None of the explanations get traction in my head.

submitted by /u/GoodMerlinpeen
[link] [comments]

How long before 2003 did scientist in the field know about element 115?

Posted: 17 Aug 2018 03:10 PM PDT

I'd love some information on this because I can only basically find the 2003 peer review for Moscovium

submitted by /u/LifebehindbarsHD
[link] [comments]

Why is it so hard to predict earthquakes?

Posted: 17 Aug 2018 01:38 PM PDT

Always seemed weird to me how little progress we have made in predictions.

submitted by /u/kay_peele
[link] [comments]

Do Earth Like Planets Have Vegetation?

Posted: 17 Aug 2018 10:57 AM PDT

If it is true that there could be as many as 40 billion Earth-sized planets orbiting in the habitable zones of Sun-like stars and red dwarf stars within the Milky Way galaxy would these planets contain some sort of vegetation for life like trees, plants, etc and can we see that?

td:dr do earth like planets have vegetation/a breathable atmosphere like our planet

submitted by /u/remag1373
[link] [comments]
vào lúc No comments:

Friday, August 17, 2018

How where auroras explained before Eugene Parker's theory of solar winds?

How where auroras explained before Eugene Parker's theory of solar winds?

How where auroras explained before Eugene Parker's theory of solar winds?

Posted: 16 Aug 2018 02:29 PM PDT

I read that Parker's theory about the existence of solar winds was met with controversy since the predominant consensus back then was that space was a complete vacuum.

So how did they explain auroras (that are caused by charged particles carried by solar winds interacting with our magnetosphere)?

submitted by /u/Yrouel86
[link] [comments]

Can something be too cold to burn?

Posted: 16 Aug 2018 09:34 PM PDT

If we want to put out a stack of sticks from our lawn, removing the fuel or oxygen is pretty easily done. Simply take away the unburned sticks or smother the fire with sand, a blanket, etc.

What about denying the fire heat, though? Without changing the amount or availability of the fuel or oxygen, like introducing compressed (and cooled) carbon dioxide, is it possible to steal enough heat from the fire to make it quit burning? If this is possible, I suspect it would have something to do with slowing the atoms to the point the fire can no longer sustain itself, but for some reason it doesn't coalesce into a consistent process in my mind.

Sorry if this is too elementary for this sub. I actually have a decent understanding of different sciences (physical science, physics, astronomy, a little chemistry, etc), but this explanation has always eluded me.

submitted by /u/JonSnoWight
[link] [comments]

Why do electrons have discrete energy levels they can occupy, and jump from between orbitals, yet do not revolve around the nucleus in orbits?

Posted: 16 Aug 2018 11:59 PM PDT

In class, I learned about the Bohr's model, which introduces the concept of discrete energy levels that electrons can occupy. However, Bohr's model is not accurate anymore as it only applies to the Hydrogen atom, hence debunking the fact that electrons move around the nucleus in fixed orbits, and instead exists in probability clouds.

In this case, how do discrete energy levels exist when fixed orbits do not exist? How do electrons 'jump' from orbit to orbit during excitation/relaxation if there aren't fixed radii of orbits for them to jump to? How do electrons even revolve around the atom then?

I'm so confused, and I think I've got something misunderstood.

submitted by /u/Xeldith
[link] [comments]

What do the amplitude and frequency of a single photon actually represent?

Posted: 17 Aug 2018 03:55 AM PDT

In the classical view, light is the combination of an electric wave and a magnetic wave going up and down in phase. Here, what is going up and down is the square root of intensity of the electric and magnetic wave. So we clearly know what the amplitude and frequency represent.

The photoelectric effect proves that the classical EM wave theory of light is incorrect. Light exists in the form of particles / wave-packets called photons. These photons also have wave-like properties. Unlike previously theorized, the energy carried by light isn't given by the intensity of its wave but by the frequency of individual photons.

From my understanding, this is what I infer:

If something is wave-like and has a frequency F, then something (X) is moving up and down at that frequency.

If something is moving up and down at a frequency, then there is obviously amplitude involved. This represents "by how much X has moved up or down at a certain point". Let's call this A.

In the classical view, X was a measure of energy or intensity. And A gives the value of X at a point in time. And F was a measure of how quickly this intensity went up and down.

Let's get to the quantum, modern view.

According to the double slit experiment's results, photons land on the screen at random positions forming an interference pattern. This pattern seems to be the result of two radial wavefronts starting from the two slits. Now, if the interference pattern is represented by a wave function, then this would give us that X for a photon is the probability of it landing at that point of space.

This would mean that the frequency F of a photon measures the speed at which this probability moves up and down, which makes no sense to me. How does a shifting probability value give rise to colors (since colors are just photons at different frequencies)?

Does this mean that when I see blue, it's because the probability of a photon hitting my eye is oscillating at 650Hz!?

Sorry if I seem dumb.

submitted by /u/MythDestructor
[link] [comments]

Are bee populations STILL declining?

Posted: 17 Aug 2018 07:04 AM PDT

I've seen some mixed reports in the slog of mainstream media. Some say they're bouncing back a little, and some appear to just have learned of the epidemic and are entering panic mode. Are they still in trouble, or is there hope?

submitted by /u/WaggyTails
[link] [comments]

Has Io ever been seriously considered a possible site for extraterrestrial life?

Posted: 16 Aug 2018 05:37 PM PDT

In Arthur C. Clarke's "2010", humanity finds extraterrestrial life for the first time on Jupiter's moon Io. In the years since, I can't recall any "real" cases for Io being a likely spot to find life in our solar system other than Earth.

Has Io ever been a serious candidate for finding life? If not, why did Clarke choose it for his novel?

submitted by /u/TrogdorLLC
[link] [comments]

Why does light bend when it refracts?

Posted: 16 Aug 2018 01:57 PM PDT

I've looked everywhere and this is driving me crazy, so hopefully someone here can help me.

I'm curious as to why light bends during refraction. I understand that when it travels from one medium to another, its speed changes, which is responsible for the refraction. What I don't understand is why this change in speed causes the light to change directions. Why wouldn't the light just pass through the medium, heading in the same direction, but at a slower (or faster) speed?

Wikipedia gives the following analogy: "Imagine a marching band as it marches at an oblique angle from a pavement (a fast medium) into mud (a slower medium). The marchers on the side that runs into the mud first will slow down first. This causes the whole band to pivot slightly toward the normal (make a smaller angle from the normal)."

In this case, why must light (the marching band) change it's course of motion because of the new angle cause by the slowing down of one side? Why doesn't the light just keep heading straight, but have a weird slant in the front instead of a straight line?

I hope this makes sense, please ask if I need to clarify anything. Thanks for the help in advance.

submitted by /u/ArmandLegGames
[link] [comments]

Why/How does heavy doping cause a thinning of quantum tunneling barrier in semiconductors?

Posted: 16 Aug 2018 08:26 PM PDT

I know that heavy doping causes the barrier between a metal contact and a semiconductor (say silicon) to become thinner. But, I am not clear on the details of how or why this should happen....

Is it because there is some number of electrons that have to move to the metal side to balance out the junction, and the heavy doping allows this number to be reached in a thinner area?

Any light you can shed on this problem would help me out!

submitted by /u/WarlordBeagle
[link] [comments]

If the universe is 13,7 bilion years old, stars burn for 4-5 billion years and supernovae birth new stars along with most elements, how is it that the atoms in our bodies (for instance) have been through many stars, as opposed to just 2 or 3?

Posted: 17 Aug 2018 03:38 AM PDT

Are our pinky and ring fingers mechanically linked?

Posted: 16 Aug 2018 06:33 PM PDT

I can put my ring finger down by itself, no problem. But whenever I try to put my pinky down, the ring finger wants to come along with it. Why is that? How come it doesn't work vice versa?

submitted by /u/Uncle151
[link] [comments]

Could a satellite gather molecular gases from orbit to maintain its orbit?

Posted: 16 Aug 2018 01:37 PM PDT

Assuming the power and technology to actually do it, are there enough gas molecules in the various orbit distances to be collected, compressed, and used as thrust to maintain speed and attitude to continuously hold orbit forever? I know the satellite's orbit and mass would matter a lot, but is it even possible at any scale?

submitted by /u/Ashandrik
[link] [comments]

Can someone explain the channel polarization in polar codes?

Posted: 16 Aug 2018 08:58 PM PDT

I am currently studying Polar Codes in 5G, but I do not quite understand how the algorithms work except from the concept that it aims to approach Shannon capacity by using N copies of a channel to seperate them into either complete noise or noise free. Thank you

submitted by /u/howleeshits
[link] [comments]

Are tritium illuminated watches truly safe to wear when bremsstrahlung is considered?

Posted: 16 Aug 2018 10:26 AM PDT

Manufacturers of these GTLS (gaseous tritium light source) watches love to claim that they are completely harmless because the beta decay of Tritium cannot penetrate intact skin. They never mention the X-ray emission caused by bremsstrahlung - the reaction between the phosphorus and tritium.

Having an always-on low energy x-ray source strapped to your wrist can't be safe... can it?

submitted by /u/topsyandpip56
[link] [comments]
vào lúc No comments:

Thursday, August 16, 2018

Is there a spot where the big bang happened? do we know where it is? Is it the center of the universe? If you go there, is there a net force of zero acting on you in all directions ( gravity)

Is there a spot where the big bang happened? do we know where it is? Is it the center of the universe? If you go there, is there a net force of zero acting on you in all directions ( gravity)

Is there a spot where the big bang happened? do we know where it is? Is it the center of the universe? If you go there, is there a net force of zero acting on you in all directions ( gravity)

Posted: 15 Aug 2018 12:30 PM PDT

EDIT: Wow thanks for all of the answers and the support, this is my most popular post yet and first time on trending page of this sub! (i'm new to reddit)

submitted by /u/skylerchaikin
[link] [comments]

If we can see 13.2 billion light years away with the Ultra Deep Field, does that mean that the universe was that big 13.2 billion years ago?

Posted: 16 Aug 2018 12:28 AM PDT

So first let me say I am so excited to find this page, I've been looking for something like this for a long time.

So the universe started x number of years ago (13.6 billion?) and so that is the limit of what we would be able to see. Ultra deep field I believe saw up to around 13.2? Billion light years away (essentially 13.2 billion years into the past).

And I believe it would have been the same story if it was pointed at a completely different part of the sky. And also would be the same if someone way out there had one pointing at us.

Which would make not only everywhere the center, but everywhere also the edge (of the observable universe).

So my question/confusion comes in, because doesn't that mean that the universe was that big that long ago?

Or even more, what if (theoretically) you leap frogged the telescopes, and we saw 13 billion light years away (13 billion years into the past) and then put a telescope there pointing in the same direction, and so on?

I feel like I'm making an incorrect assumption somewhere.

submitted by /u/brianenergy
[link] [comments]

The quasar quasar PKS1353-341 is 46 billion times brighter than the sun. What does that mean for the surrounding galaxies?

Posted: 16 Aug 2018 02:53 AM PDT

A very bright quasar was found to be obscuring hundreds of galaxies.

Quoting from the article:

the quasar's light is so bright that it has obscured hundreds of galaxies clustered around it.

In their new analysis, the researchers estimate that there are hundreds of individual galaxies in the cluster, which, all told, is about as massive as 690 trillion suns. Our Milky Way galaxy, for comparison, weighs in at around 400 billion solar masses.

The team also calculates that the quasar at the center of the cluster is 46 billion times brighter than the sun.

What does this mean in practice? How far away would you have to be for the light not to be unbearable?

submitted by /u/mvuijlst
[link] [comments]

Why does a seemingly-small global temperature change, say a couple degrees cause so many changes and why is it so catastrophic?

Posted: 15 Aug 2018 03:28 PM PDT

Do chimpanzees have unique fingerprints just like humans? If they do, do they also form patterns of swirls, loops or arches?

Posted: 15 Aug 2018 08:12 PM PDT

Basically just wondering if a chimpanzee could use TouchID on a smartphone.

submitted by /u/Zandirian
[link] [comments]

Supposing a primordial Black hole of one Earth mass fell into the Earth, about how much time would it take to absorb our planet?

Posted: 15 Aug 2018 08:16 PM PDT

Pretty much what it says.

Supposing there is such a thing, I suppose it would be very small and have a very limited surface to interact with Earth while it sort of orbits around the center of mass in the core.

submitted by /u/Gargatua13013
[link] [comments]

Why is the color in rain filled clouds so dark?

Posted: 15 Aug 2018 11:38 PM PDT

I spent a weird amount of time the other day observing the color of rain filled clouds, and so I was wondering, why are rainy clouds dark grey, when in fact it's conformed of water droplets which are transparent. I thought maybe it had to do with the temperature of the water, but hot water is just less clear than cold water, not darker in any way; so, why are those clouds so dark? Is it because of the way it refracts light? I would really love an answer to this question because it truly does intrigue me deeply.

submitted by /u/lindamarin
[link] [comments]

How are music instruments sounds affected by a different gravity on another planet?

Posted: 16 Aug 2018 01:37 AM PDT

Why exactly is speed of light speed limit?

Posted: 15 Aug 2018 10:41 AM PDT

For so long I have been trying to find explanation to why speed of light is speed limit.

The answers that I get are: "Because time stops" or "You would need infinite energy to reach speed limit" or "You can only reach 99.99% of speed of light", other explanations that are formula-a-like contain constants like Planck length or vacuum permittivity which again contain c. I have been stuck in this loop for a long time and I would be very grateful if someone could explain why speed of light is maximum speed limit give me some directions to some videos for graphical explanation or some literature with some formulas that I could plug in numbers.

submitted by /u/Let_me_tug_it
[link] [comments]

If glass has no regular crystalline structure, why does tempered glass tend to break into rectangles instead of completely randomly shaped pieces?

Posted: 15 Aug 2018 10:00 PM PDT

Is it possible to distill in room temperature, just slowly?

Posted: 16 Aug 2018 01:22 AM PDT

For instance, you put alcohol in room temperature 'boiler' and then just run the thing through condenser. Wouldn't the alcohol just vaporize making the distillation happen only slowly?

submitted by /u/buggaz
[link] [comments]

Why is magnetism seen in elements like Iron - but not elements like Carbon or Silicon?

Posted: 15 Aug 2018 08:36 PM PDT

I've read that magnetism in elements like iron - is caused by lone electrons in orbitals that spin in 1 direction and that magnetism is merely the cumulative effect of these electrical charges moving through space with 1 spin.

But according to Hund's rule, the electron configuration of many elements with 4 valence electrons such as Carbon or Silicon also have their outer orbitals filled with electrons spinning in only 1 direction.

So why are elements like Iron magnetic but not elements like Carbon or Silicon?

submitted by /u/Phamellie
[link] [comments]

How aerodynamic are hatchbacks?

Posted: 16 Aug 2018 12:05 AM PDT

How do hatchbacks compare with sedans when it comes to induced drag? Which is more aerodynamic, and why?

submitted by /u/88880
[link] [comments]

How does unpolarized light work? If unpolarized light is a collection of waves of random polarization and phase, distributed randomly, wouldn’t the electric field at any point add up to zero?

Posted: 15 Aug 2018 07:32 PM PDT

What is the highest electrical resistance possible?

Posted: 15 Aug 2018 02:46 PM PDT

Most questions answer this in terms of conductive material such as aluminum vs. rubber etc. What about air? What about a vacuum?

I recently bought Corona Dope for an electric fence project that was shorting out, and I was wondering wtf that stuff is made of that it stopped the shorts between two contacts that were arcing in just air. Is this material more resistive than air?

submitted by /u/stevenette
[link] [comments]

Can we expect a decisive answer about the existence of a ninth planet any time soon? Or is progress difficult and slow?

Posted: 15 Aug 2018 11:23 PM PDT

Do vegans have different gut bacteria?

Posted: 15 Aug 2018 05:16 PM PDT

I know that animals like horses and cows have different bacteria in their GI tracts due to only eating plants and no meat, which is why their manure can be used as fertilizer. If humans eat a strictly vegan diet long enough, do their GI tracts adjust the bacteria in the same way?

submitted by /u/bearmahogany
[link] [comments]

What thermal quantity do we sense?

Posted: 15 Aug 2018 07:00 PM PDT

Obviously we can distinguish between hot or cold, but what exact physical quantity do our bodies "measure" or sense? For example, temperature, thermal capacity, heat flux, heat rate, etc.

I don't think we sense temperature, because a metal at room temperature will feel colder than a nonmetal at room temperature.

What thermal quantity do we sense when we touch things?

submitted by /u/AdventureMan5000
[link] [comments]

For how long has animal psychopathology been a field of study?

Posted: 16 Aug 2018 01:33 AM PDT

I would assume that ''strange behaviour in animals'' has been studied for quite a while, but not as psychopathologies.

I tried to do some googling and the earliest book I could find is ''Origins of Madness: Psychopathology in animal life(1979)'' by J.D. Keehn, but I'm not sure if this is the earliest instance of it.

Sorry, I'm not sure if this falls under biology or psychology.

submitted by /u/SpeaksWithPictures
[link] [comments]

Why does the shape of the moon change depending on where you are on the Earth?

Posted: 15 Aug 2018 01:36 PM PDT

For example, I live in England and the moon waxes and wanes in a lateral, sideways motion day to day (so the crescent is shaped in a C). However, I'm currently on the equator and it waxes and wanes upwards and downwards (so the crescent is shaped like a U). I can't quite figure it out.

submitted by /u/cr214
[link] [comments]

In quantum theory, how do particles get entangled?

Posted: 15 Aug 2018 01:15 PM PDT

I'm trying to understand entanglement, and there are a lot of articles about it, but I have yet to find one that explains how to entangle particles or photons in the first place. To simplify the question, would it be possible to explain how to entangle two electrons, and some of the implications of this. No complex maths, please (I only did physics to A level some years ago).

submitted by /u/RegularHovercraft
[link] [comments]

Does keeping a spring compressed cause it to become looser? (This question coming from Nerf, but applies in many contexts)

Posted: 15 Aug 2018 06:08 PM PDT

Let me explain the context from which my question is coming, but ultimately, it is a general question. In Nerf, some blasters use magazines to feed darts. The magazine has a spring, which pushes the darts upward so they can be fed. Some people say leaving the magazines loaded is a bad idea because keeping the spring compressed will cause it to degrade performance. Some say that doesn't happen, or that wouldn't happen in a period of time that relates to play.

Similarly, some blasters are spring powered. Again, some people say to not leave the blasters primed where the spring is in a compressed position. Some say it doesn't matter.

There seems to be conflicting information in google searches. Some say compression causes deformation, some talk about fatigue limits, elastic regions, and so on. It seems that a lot of people are trying to apply their common sense, but it's not clear whether it works in this case for practical applications.

So, does keeping a spring compressed cause it to lose decompression power?

submitted by /u/Okumam
[link] [comments]
vào lúc No comments:
Subscribe to: Comments (Atom)