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Tuesday, May 7, 2019

What makes Jupiter's giant red spot red?

What makes Jupiter's giant red spot red?

What makes Jupiter's giant red spot red?

Posted: 06 May 2019 10:36 AM PDT

If the universe is expanding, isn't all matter/energy in the universe expanding with it?

Posted: 07 May 2019 04:59 AM PDT

I've just watched a program about the end of the universe and a couple questions stuck with me that weren't really explained! If someone could help me out with them, I'd appreciate it <3

So, it's theorized that eventually the universe will expand at such a rate that no traveling light will ever reach anywhere else, and that entropy will eventually turn everything to absolute zero (and the universe will die).

​

If the universe is expanding, then naturally the space between all matter is also expanding (which explains the above), but isn't the matter itself also expanding by the same proportions? If we compare an object of arbitrary shape/mass/density now to one of the same shape/mass/density trillions of years from now, will it have expanded? If it does, doesn't that keep the universe in proportion even throughout its expansion, thereby making the space between said objects meaningless?

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Additionally, if the speed of the universe's expansion overtakes the speed of light, does that mean in terms of relativity that light is now travelling backwards? How would this affect its properties (if at all)? It is suggested that information cannot travel faster than the speed of light, and yet wouldn't this mean that matter in the universe is traveling faster than light?

​

Apologies if the answers to these are obvious! If not a physicist by any stretch, and wasn't able to find understandable answers through Google! Thanks for taking the time to read this!

submitted by /u/Brandacle
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Is the steam emitted from a nuclear power plant radioactive?

Posted: 06 May 2019 11:32 PM PDT

Why are B- cells called Plasma Cells knowing that there are no cells in Plasma ?

Posted: 07 May 2019 07:55 AM PDT

What is the difference between "Antigen" & "Immunogen" ? And how does the the immune system act with each other ?

Posted: 07 May 2019 07:54 AM PDT

When a song is stuck in our head, do we subvocalize it just like our internal monologue?

Posted: 06 May 2019 01:03 PM PDT

How can one calculate the volume of a holey cube?

Posted: 06 May 2019 03:09 PM PDT

Take a cube with, say, sides of a 10 cm length, and then you drill a hole with a radius of 1 cm perfectly through the centre of each face to the other side. The volume should be the volume of the cube, minus the volume of three cylinders with a radius of 1 cm and a length of 10 cm, right? But that doesn't take into account the area where the cylinders intersect. Now, I've heard something about the Steinmetz solid, but as far as I know, that only covers the area where all cylinders intersect, ignoring the corners where only two cylinders intersect.

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How do I calculate the volume of a "holey cube"?

submitted by /u/noexplanations
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How do we keep track of biodiversity and the population of species when there are so many and some can move great distances?

Posted: 06 May 2019 12:23 PM PDT

What determines whether smoke is white or black?

Posted: 07 May 2019 04:32 AM PDT

Burning wood gives off white smoke, burning diesel gives off black smoke. There doesn't seem to be much in between white and black, although I've seen yellow smoke in some chemical reactions, and of course smoke bombs can be colored. But in your basic fire, white or black seem to be normal.

submitted by /u/AkumaBengoshi
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How are Cowbirds and other birds that lay eggs in other’s nests able to maintain calls and behaviors despite having no learning from parents?

Posted: 06 May 2019 03:28 PM PDT

I recently learned that some insects release a pheremone when they're killed that attracts other insects to their corpse. What is the reason for this? Wouldn't it make more sense to release a chemical than warns of danger?

Posted: 06 May 2019 04:09 PM PDT

Does the infrared output of the sun fluctuate in such a way that it affects temperatures on earth; or is the change in temperatures on different parts of the earth purely due to fluid dynamics in the atmosphere and the tilt of the earth on its axis?

Posted: 06 May 2019 02:41 PM PDT

I had read somewhere, some time ago that the intensity of the heat in summer periods on earth could be tied to sunspot activity. I am uncertain if this is true. I am also curious why is it that temperatures on earth are inconsistent. If the infrared output of the sun is constant and the rotation of the earth is constant, why does the eath not stay at an even temperature like rotisserie chicken (for example)?

submitted by /u/dbloch7986
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Why does Jupiter only have one giant red spot? And why on that specific location?

Posted: 06 May 2019 01:50 PM PDT

How do handheld massagers with COLD functions work?

Posted: 06 May 2019 01:48 PM PDT

My mother recently bought this personal massager that has a function that makes a metal pad on the device cold to touch (according to the product description, 37 to 44ºF). From my surface investigation, I don't really feel any heat escaping from elsewhere on the device. I understand the basic principles of refrigeration and know that heat can't just disappear, but I couldn't really find any answers from web searching about how the cold in this application is being "generated."

submitted by /u/matthewofthemany
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How different are humans now from our ancestors 2000 years ago?

Posted: 06 May 2019 01:30 PM PDT

Whenever a post is made about a graffiti dick found in a biblical era bathhouse, it reminds me that 2000 years isn't even a blink of an eye relative to how old our planet is. In a weird way, it is comforting to know that humans be humans and across millennia and across cultures, we still find the same things funny. How different (or similar) were our biblical era ancestors?

submitted by /u/Shootrmcgavn
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How smoothe is the surface of a droplet of water as compared to the surface of a planet like Earth?

Posted: 06 May 2019 07:56 PM PDT

I've heard it said that the Earth is about as smooth/round as a pool cue. It made me think about a water droplet floating in zero gravity.

How would the surface of the water droplet compare to the surface of larger spheres in the universe (ike a pool ball, planet, star, or neutron star) if they were compared proportionally?

How would we even compare them?

submitted by /u/fulgoray
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Why are transformer and brushless motor stator cores made of steel laminations?

Posted: 06 May 2019 12:36 PM PDT

I want to build a BLDC motor, but need to understand the purpose of those steel laminations.

I've heard that electrical steel is used for the plates, why that and not regular steel?

Could I cnc the steel and glue it together with some sort of resin, would that work?

Thanks!

submitted by /u/KarolHojka
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How should I understand the warping of time in relativity?

Posted: 06 May 2019 05:43 PM PDT

I understand that spacetime is a four dimensional continuum that is warped by the presence of mass/energy which in turn guides the mass and energy that moves through it. I also understand the equivalence principle that ultimately concludes that gravity is not a force but a consequence of this warping. What I want to understand better is how a stationary object in undistorted, flat spacetime when brought into a warped section of spacetime then begins to accelerate. As I understand it, its a product of a differential warping of the time dimension relative to space, so that unlike a stationary object that has time and space positions at the same place, the curvature of time is greater, which causes a displacement in space when the object follows that more warped path. Does that visual capture the concept properly? And is there more to understand? Sorry for dragging out this explanation.

submitted by /u/37litebluesheep
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Can polarized dielectrics behave similar to conductors while in motion in an external magnetic field?

Posted: 06 May 2019 05:47 PM PDT

When comparing them with a conductor; Imagine a polarized dielectric normal(surface) to an external magnetic field.

A current carrying conductor in a magnetic field( IL x B) will experience a force. Wouldn't the same occur for a dielectric material being polarized by an external E-field, and as the atoms of the dielectric stretch v x B, can be non-zero?

Secondly, if the polarized dielectric was moving in an external magnetic field (with v x B) wouldn't the charges stretch/compress (if v x B is still considered)?

submitted by /u/9tothe9
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Why does pressure relax tensed muscle?

Posted: 06 May 2019 02:09 PM PDT

If FAD is short for flavin adenine dinucleotide, and a nucleotide includes one monosaccharide, one phosphate group and one nitrogenous base, where is the second monosaccharide?

Posted: 06 May 2019 11:51 AM PDT

I only see one when I look at the formula. Is the other one in open-chain form?

submitted by /u/Danny_Kaye
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How does ingesting sodium/potassium affect the "sodium-potassium pump"?

Posted: 06 May 2019 12:21 PM PDT

is there a direct correlation between increased levels of sodium/potassium in the blood to differences in HR, BP, and EKG readings? Would ingesting a similar amount of each counteract the effects of the other?

For example: increased sodium = increased HR/BP and increased potassium = decreased HR/BP

submitted by /u/CrzyNannerMunky
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Monday, May 6, 2019

As the ISS grew over time, it’s center of mass must have changed location. How did their thrusters change their behavior or were they literally moved to a new location?

As the ISS grew over time, it’s center of mass must have changed location. How did their thrusters change their behavior or were they literally moved to a new location?

As the ISS grew over time, it’s center of mass must have changed location. How did their thrusters change their behavior or were they literally moved to a new location?

Posted: 05 May 2019 11:21 AM PDT

Do any plant cells undergo apoptosis in a similar fashion to animal cells?

Posted: 05 May 2019 01:47 PM PDT

Why can't HIV be spread by vectors?

Posted: 05 May 2019 01:30 PM PDT

Why do some vaccines only need to be given once, while others such as the flu jab need to be done yearly?

Posted: 05 May 2019 03:45 PM PDT

What is actually celiac disease?

Posted: 05 May 2019 11:16 AM PDT

Is it an intolerance? Or an allergy? Which kind of immunoglobulins does it involve - or, generally, how does it affect the immune system? Which are the causes? And is there any possible treatment?

submitted by /u/yabot
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How can foods labeled "Refrigerate after opening" stay on a shelf for extended periods of time without spoiling but then must be refrigerated after opening to prevent spoiling?

Posted: 05 May 2019 10:34 AM PDT

What changes the size of rain droplets?

Posted: 05 May 2019 09:59 PM PDT

I noticed the other day that sometimes when it rains, it rains tiny little pitter patter raindrops, but other times there huge globs of water. Why is that.

submitted by /u/fartface201
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Reflected light from a colored object?

Posted: 05 May 2019 12:35 PM PDT

From my understanding, when I shine a white light on a green object the atoms electrons 'absorb' the energy as the light has the same resonant frequency as the electrons which allows for the max amount of energy transfer. This means that the colors(wavelengths) other than green are absorbed the most while the green light is reflected.(If this is wrong please correct me)

My question is, by what mechanism is the green light reflected from the object, is it reflected by the electric field of the atom? Is it absorbed and re-emitted? Does it undergo some sort of scattering, if so what one?

submitted by /u/ExcuseTheLag
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Molecularly, how exactly do carcinogens cause cancer?

Posted: 05 May 2019 07:00 PM PDT

Have any lab created elements been discovered in meteorites or other extra terrestrial samples?

Posted: 05 May 2019 07:52 AM PDT

Are the armpits of animals, like monkeys for example, same as human pits? As in it sweats, smells there more?

Posted: 05 May 2019 03:42 PM PDT

When you feel full after eating, is it because your stomach is literally not able to fit more food or is it just your brain telling you to stop eating?

Posted: 05 May 2019 02:34 AM PDT

Density of Plasma/Amount of Fusion in a Fusion Reactor?

Posted: 05 May 2019 01:54 PM PDT

At the ITER website (https://www.iter.org/mach), talking of their tokamak reactor, it says:

The tokamak is an experimental machine designed to harness the energy of fusion. ITER will be the world's largest tokamak, with a plasma radius (R) of 6.2 m and a plasma volume of 840 m³.

At the 'Do The Math' website (https://dothemath.ucsd.edu/2012/01/nuclear-fusion/), talking of fusion power, it says:

we need 1.3×1032 Li atoms annually to produce our world consumption of 4×1020 J. That's about 1500 metric tons of lithium annually

Lithium's density is 0.534 g/cm3, which means that a volume of 840m³ would hold about 450 metric tons of it, roughly 1/3 of the total needed to power the entire world. Presumably the plasma version weighs a lot less, and also it's not fusing at a rate of 100%.

What I'm curious about is (a) how much less, and (b) of that total, when the fusion reactor is running, how much is actually going to be fusing at any one time? 1%? 0.00001?

The fusion reactor, as I understand it, is supposed to squeeze the plasma and heat it up until fusion starts, which excess heat you use to boil water and turn turbines. That means there's going to be 840m³ of really hot plasma, but not all of it's going to be fusing. If the magnets fail, how quickly does the plasma cool off? What's to stop it contacting the sides of the reactor and melting them, or even burning through to where the water is and causing a steam explosion?

submitted by /u/MyActualRealName
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Why is the blood of horseshoe crabs blue?

Posted: 05 May 2019 07:50 PM PDT

Do ACE inhibitors lower blood CO2 levels?

Posted: 05 May 2019 07:45 AM PDT

If they do it - how?

submitted by /u/tisho23
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Why is decreasing a parcel of air's temperature down to its wet bulb temperature considered to be an isenthalpic process?

Posted: 05 May 2019 06:47 AM PDT

Explanations online say that all heat lost by the air is gained by the water, which evaporates and becomes part of the air, so the heat lost is canceled out. I get that, but isn't there some enthalpy contained by the water before it evaporates that needs to be accounted for? So let's say the air is originally completely dry and has an enthalpy of H_a, a mass of m_a, and a specific enthalpy of h_a (H_a/m_a). The unevaporated water initially has an enthalpy of H_w, a mass of m_w, and a specific enthalpy of h_w (H_w/m_w). Now let's say the water is evaporated into the air until it reaches its wet bulb temperature. After the evaporation, the air would have an enthalpy of H_a - Q and the evaporated water would have an enthalpy of H_w + Q, where Q is the heat transfer. Putting this all together, the final enthalpy of the fully saturated air would have an enthalpy of H_a - Q + H_w + Q = H_a + H_w and a specific enthalpy of (H_a + H_w)/(m_a + m_w), which are not equal to the initial enthalpy of specific enthalpy. What am I missing here?

submitted by /u/bnpm
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If you rip / cut off the leaves from a plant, do the cells inside die instantaneously ?

Posted: 05 May 2019 03:19 AM PDT

Obviously the plant doesn't function as before, but what exactly happens to the individual cells, in terms of biology?

submitted by /u/idejabajra
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Sunday, May 5, 2019

If a pregnant woman has cancer, is it possible for the cancer to spread to the fetus?

If a pregnant woman has cancer, is it possible for the cancer to spread to the fetus?

If a pregnant woman has cancer, is it possible for the cancer to spread to the fetus?

Posted: 04 May 2019 07:56 PM PDT

How far below the surface of the water does a hurricane disturb the natural state?

Posted: 05 May 2019 06:36 AM PDT

Why do we feel so disoriented after waking up from a deep sleep?

Posted: 05 May 2019 04:08 AM PDT

How do we judge the intelligence of other species?

Posted: 04 May 2019 09:42 PM PDT

Question originates from my personal experience with Cuttlefish. I'm used to being seen by animals, and most animals seem to treat people the same way.

The Cuttlefish are kind of unsettling in that they actually look inquisitive. There seems to be an intelligence to them like with dolphins that is missing in most animals I've had experience with, being cats, dogs, horses, even monkeys.

submitted by /u/iAzire
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Water have higher heat capacity than air, but also conduct heat better, so my question is which one is a better insulator, and what's the different between heat capacity and conductivity?

Posted: 05 May 2019 05:44 AM PDT

Really sorry about my non native English

Also if it wasn't obvious i wanted to know which is a better insulator in regards to its heat capacity and conductivity

submitted by /u/Staviao
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Where do amyloid plaques come from and how are they produced? Also, how are TDP-43 proteins produced?

Posted: 05 May 2019 07:02 AM PDT

I read an article (https://apple.news/AyW8ZMW24QCG33M9iP5EjrQ) recently about a new type of dementia called Late which appears to only affect people ages 80+ and apparently, nearly a third of the people diagnosed with Alzheimer's may instead have this. Late is linked to an accumulation of the protein TDP-43 instead of amyloid plaques. So why is it that the brain fails to stop the accumulation of both of these proteins? And how are both of them formed? (Also, I'm sorry if I messed something up in the questions, I'm still new to posting.)

submitted by /u/DarthMasken4088
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If neurons are amitotic, how is cancer of the brain possible?

Posted: 04 May 2019 09:26 PM PDT

Does cancer unlock some hidden potential for brain cells to divide? If so, how?

submitted by /u/Burrito8
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Are there any celestial objects with a significant net charge?

Posted: 04 May 2019 03:16 PM PDT

I know large bodies tend to have neutral charge, however I'm curious to see if there are any exceptions.

submitted by /u/ostrich-scalp
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Can material be both ferroelectric and paraelectric at the same time while acting as a dielectric?

Posted: 04 May 2019 06:19 PM PDT

Trying to write a report on the second order phase transition of triglycine sulfate crystal and knowing this would clear stuff up. Any help is appreciated.

submitted by /u/Task876
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What stops our bodies from decomposing while we are alive?

Posted: 04 May 2019 07:08 AM PDT

We constantly have flesh eating bacteria living in our bodies. But somehow, they wont start decomposing out bodies until we die. Why is that? What is in out bodies while we are alive that keeps up from stopping to decompose, alongside other animals across the world?

submitted by /u/BurntToast01
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What would be the consequences of magnetic monopoles being discovered?

Posted: 04 May 2019 10:04 AM PDT

At this point would it be good or bad for Physics if they were discovered?

submitted by /u/Riptide898
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While the hydrogen content in the atomosphere of Titan is tiny, is there a possibility that higher concentrations of H2 to exist near the surface through other means, such as chemical reactions or outgassing?

Posted: 04 May 2019 11:33 AM PDT

Do nuclear warheads require neutron moderators?

Posted: 04 May 2019 11:14 AM PDT

Context: I know in nuclear fission power plants they use graphite, heavy water, etc. to moderate the neutrons - slow them down so that they have a higher chance of propogating the reaction. I also know that nuclear warhead uranium requires 90+% enrichment.

So, how do they get the high-speed neutrons to continue the nuclear chain reaction in such a way that it explodes? Do they mix graphite and other things in with the uranium or are moderators no longer necessary once you have high enough enrichment %?

submitted by /u/deadrunordtech
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Is it possible for a planet to be “flat”?

Posted: 04 May 2019 08:44 PM PDT

Obviously Earth is not flat. But, is it possible for a planet in a stable orbit around a star to be flat, or flattened, in any way?

The biggest obstacle I see with this is that gravity will tend to compress any flatter object into a more spherical one. But can a planet be flattened temporarily? Or be in some weird situation where it can maintain its flatness?

Thanks!

submitted by /u/Baron_Sigma
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Do the heart or lungs increase and decrease in size depending on altitude? (And is there a difference between growing up in it or not?)

Posted: 04 May 2019 03:53 AM PDT

I grew up at around 1500 meters above sea level (4921.26 feet). That was 17 years of my life.

During this time my grandma mentioned that people that live in high altitudes grow up to have a bigger heart from what she saw on TV.

This makes sense to me (though I've no clue if it's correct).

Is this true?

And what prompted me to ask the question: A friend said that even if that is the case, she believes that actually when you go back down to closer to sea level (now I live at 500 meters / 1640.42 feet), then your heart and lungs adjust back down, losing whatever upgrade they might have had.

Is that true?

submitted by /u/greduan
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