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Monday, January 25, 2021

How exactly do flashbangs produce light?

How exactly do flashbangs produce light?

How exactly do flashbangs produce light?

Posted: 24 Jan 2021 08:03 PM PST

Why do we have kneecaps but no elbowcaps?

Posted: 24 Jan 2021 01:10 PM PST

Why are some chemical reactions irreversible?

Posted: 25 Jan 2021 03:06 AM PST

How is hearing protection from impulse noise different than that from continous nose?

Posted: 24 Jan 2021 04:08 PM PST

Hi,I'm curious if someone with background in audiology and/or hearing protection could explain the following:

  1. I have some background in acousitcs and I remember, that maximum allowed exposure to continuous noise that does not result in any permanent damage is 82dB for 8 hours/day and that this time is halved wtih each 3dB of increase (at least by EU norms, I know that in the US the limit is less strict). The question I have is following: how was that limit established and how accurate it is? Could I blast my ears everyday with let's say 103dB of noise for exactly 3 minutes and expect no hearing loss whatsoever?
  2. Hearing protection with respect to impulse noise like gunfire. From various sources online I found out that gunshots can measure anywhere in the range form 140dB to 170dB, at the shooter's ear. How many dB of noise reduction is needed for complete safety in that case? Is it enough if the shooter uses earmuffs that reduce the noise by let's say 30dB - from 170dB to 140dB and if so, how do we know it's safe and won't cause damage over the course of years or decades? Is there a limit, on how many shots could a shooter take in such case before damage to hearing occurs, in spite of using hearing protection and if so, how can that limit be established?
submitted by /u/M_ish_A
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When boiling the substance, are the bubbles that appear air that's becoming trapped inside the liquid then escaping? Or is it the material itself evaporating?

Posted: 24 Jan 2021 03:06 PM PST

How exactly does loud noise and/or frequency cause damage to the structures of the ear?

Posted: 24 Jan 2021 01:06 PM PST

Based on my Google/Wiki/YouTube research so far, sound pressure waves hit the eardrum / tympanic membrane - and this membrane is connected to a series of small bones (ossicles) which ultimately push into the "oval window" (fenestra vestibuli) of the cochlea and cause ripples through the fluid inside. The movement of this fluid stimulates hair cells (and somehow the different frequencies only impact certain areas of hair) which connect to nerves, where the signal gets processed by the brain.

However, damage doesn't seem to get covered in detail anywhere - just that it happens, but without elaboration as to why or how it happens.

My question is twofold:

  1. How do loud noises cause hearing damage exactly? Does a loud / strong pressure wave move the tympanic membrane too harshly and cause it to rip? Does it damage the ossicles by making them move too strongly or sharply? Does it damage the round window underneath (the fenestra cochleae) that allows the fluid to move in the first place? Does the pressure wave cause damage to the hairs by moving them too aggressively? What exactly is prone to damage with a loud noise?

  2. How about damage caused by frequency? Human hearing ranges from 20 - 20000 Hz, which I presume is due to the types of hair cells in our cochlea and the frequencies they are sensitive to. I don't understand how a pressure wave through the liquid somehow wouldn't stimulate all the hair cells or why only certain hairs are triggered over others, but how might frequency cause damage even if we can't hear it? Similar to question 1, which areas are prone to damage?

submitted by /u/RedVelvetIsntAThing
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What makes platinum such a good catalyst in organic chemistry?

Posted: 24 Jan 2021 11:07 PM PST

Why don't T cells divide into memory T cells before encountering a pathogen?

Posted: 24 Jan 2021 07:24 PM PST

then body can already be immune to the disease or at least combat it better

submitted by /u/yyfcdthyfdfooh
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Are electric car lithium batteries recyclable? Will there be parts of the battery that will be dangerous to earth that we don’t hear about everyday?

Posted: 24 Jan 2021 11:42 AM PST

Sorry if the flair is wrong. With all this news about electric cars and lithium and cobalt mining being the next step to 'go green', I have no idea what the end result really is nor find it online.

submitted by /u/HannukahJizzTonsil
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Is there any particular reason why all of the gas giants formed in the outer reaches of the solar system and not closer to the sun?

Posted: 24 Jan 2021 01:33 AM PST

Have we observed any behavioral responses to viral pandemics among other mammals?

Posted: 24 Jan 2021 08:47 AM PST

I am curious to know if we have observed any behaviors among other mammals that seem to be responses to viral pandemics (abandonment, isolation, etc.)?

submitted by /u/SannySen
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What is the purpose of lowering PCR thresholds for Coronavirus tests?

Posted: 24 Jan 2021 08:13 AM PST

In Texas a day or two after rain, tiny piles of pill-shaped dirt cover fields- what are these and where do they come from?

Posted: 23 Jan 2021 04:03 PM PST

I was walking my dog this afternoon and noticed them.

But then I remembered I've seen these like all my life, and I'm pretty sure it's only after rain.

submitted by /u/Jakeysuave
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How did the sexual process evolve in eukaryotes?

Posted: 23 Jan 2021 08:42 PM PST

I've been trying to find answers to this question on this sub and online, but I couldn't find much about the theory of how organisms developed haploid cells and a way to transfer them, and what I did find I had a hard time understanding. I've gathered that eukaryotes are the ancestors of organisms that reproduce sexually, so the mutation would have likely started in eukaryotes millions of years ago. What enabled a eukaryotic organism to transfer its genetic material to another eukaryotic organism?

In my layman's understanding, it seems that if an organism has a mutation that is useful for sex (like haploid cells or a sexual mechanism, some way to transfer DNA), but then can't find another organism with a complimentary sex mutation in reasonable proximity before it dies, it won't reproduce that useful mutation and the mutation ends there. How did sex evolve when two organisms that needed complimentary sex mechanisms/DNA-combining systems had to mutate that at the same time and place?

side note: on a lot of the threads where this question is asked, responses point out the advantages organisms would have had once they evolved a sexual process, but I understand that and am asking how it happened specifically, as an accidental mutation

Also, please correct me if I'm wrong with my basic ideas on the subject! I really need some help understanding this

submitted by /u/PinkNinjaKitty
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vào lúc No comments:

Sunday, January 24, 2021

Given the geometry of a metal ring (donut shaped), does thermal expansion cause the inner diameter to increase or decrease in size?

Given the geometry of a metal ring (donut shaped), does thermal expansion cause the inner diameter to increase or decrease in size?

Given the geometry of a metal ring (donut shaped), does thermal expansion cause the inner diameter to increase or decrease in size?

Posted: 23 Jan 2021 08:55 AM PST

I can't tell if the expansion of the material will cause the material to expand inward thereby reducing the inner diameter or expand outward thereby increasing it.

submitted by /u/xeonisius
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How do we know the core of the Earth is hot?

Posted: 24 Jan 2021 06:06 AM PST

How do we know its really hot when no one has been to the core of the Earth? I get that there is magma and all, but where is the gaurantee that it's from the core? It could very well be from the mid layer

submitted by /u/Lil-Shrimp-Gang
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Are there caves underneath the seabed?

Posted: 24 Jan 2021 01:43 AM PST

For clarity sake, let's say the seabed of Marianas Trench. Are there caves under the seabed of the deepest depths of ocean? Are there caves underneath any segment of ocean? I know the ocean is deeper than any known cave, but hypothetically, could there be caves?

If not, what is under the floor bed? Lava? Compact rock all the way down to the mantle? Tectonic plates?

If you dug 1000 feet below Marianas Trench, what would you come across, if anything at all?

submitted by /u/AnarchyPigeon2020
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Can bird flu (h5n1) spread through vegetables?

Posted: 24 Jan 2021 07:29 AM PST

I read somewhere it can but now I can't find the source. I has caused a lot of embarrassment and it would be really helpful if someone can confirm this.

submitted by /u/Quietstuff69
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Why does licking your lips improve your ability to whistle?

Posted: 23 Jan 2021 01:19 PM PST

What DNA made this mRNA for the COViD-19 Vaccine?

Posted: 23 Jan 2021 07:38 PM PST

Hi folks,

Very not smart on this stuff but I see that the mRNA that is used in the recent COVID-19 vaccine might have to come from a cell or from DNA?

What DNA made this mRNA or what cell line was used to make the mRNA.

Thanks folks.

submitted by /u/hailennutz
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If mRNA translation errors are relatively common, how do cells prevent malformed proteins from getting out of control?

Posted: 23 Jan 2021 12:48 PM PST

I read that one of the challenges with the mRNA COVID-19 vaccines is that mRNA breaks down pretty quickly. That made me curious what happens if a cell begins to translate mRNA that has already been partially degraded. While researching that I learned that translation errors are actually quite common. Presumably cells must have a way of dealing with this. Can anybody fill me in?

EDIT: thanks for the informative answers! And just in case it's a different answer, my original question was: what, if any, danger is there in mRNA from COVID-19 vaccines becoming partially degraded and still translated by a cell?

submitted by /u/yatpay
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What's the stongest organic acid that is present in the human body?

Posted: 23 Jan 2021 11:05 AM PST

Is there anything extraordinary about our location in the universe that isn't tied to the fact that life is possible here?

Posted: 23 Jan 2021 02:47 PM PST

By "extraordinary," I mean a property that is highly uncommon in the universe. There are a few obvious ones: we're well above the 99.9th percentile in terms of how hot and how dense the space we occupy is. Our planet is also unique among others, insofar as it has liquid water, which most planets don't.

But we would expect these properties to be present in an environment that can harbor life, so it's not tremendously interesting that they're present. Once you ignore the conditions necessary for life, there isn't anything obvious that remains that makes the space we occupy particularly out-of-the-ordinary. We seem to live with some run-of-the-mill neighboring planets, orbiting a main sequence star that sits in a relatively quiet part of a galaxy that is one of many Sb shaped galaxies in the observable universe.

There are astronomical bodies that just so happen to have some cool properties that wouldn't appear to affect the capacity for life. Some planets have nonspherical moons, or moons with a particularly elliptical orbit, or live in a star system with an unusually large number of planets. Some star systems live inside nebulae. Some are on the very outskirts of their galaxy. Some galaxies are irregularly shaped, and some live in intergalactic voids. Our planet could have had any of these properties and life would still be possible (though it may look different). But it doesn't.

But I'm not convinced that there aren't any interesting properties about where we are that aren't tied to life existing here in the universe. Is there anything about our planet, our star system, our local group, our galaxy, or our galactic cluster that is extraordinary merely by coincidence?

submitted by /u/ArbitraryRenaissance
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What determines women's breast size?

Posted: 23 Jan 2021 11:36 AM PST

Tried googling, and you can imagine how hard it was to find a clear scientific answer.

I gather it's genetics, but what are the underlying reasons for various breast sizes, evolutionarily and adaptively speaking? How did this evolve over time? How does environment influence this characteristic?

I am interested in specifics and the broader context.

submitted by /u/anonymous_divinity
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Why is the pressure caused by non compressible fluid inside the wider area of a pipe more than that in the narrower area?

Posted: 23 Jan 2021 11:38 PM PST

So imagine there's a pipe and it is wide at one end and narrow at the other. Now using the equation of continuity, we know AV=constant therefore velocity of fluid will be more in the narrower part. Now since the velocity is more in the narrower end, I would assume that it's also exerting more pressure on the walls of the pipe and as the flow of fluid is slower in the wider part, the pressure would also be less. Also Pressure = Force/Area hence pressure is inversely proportional to area, which would further support my argument. But clearly, this thinking is wrong. I think we would use Bernoulli's principle here to determine the pressure relationship but I can't figure out how to do it. The only thing I know for sure is that pressure WILL be more in the wider part and less in the narrower part. Now I just need an explanation for this.

submitted by /u/Homoneanderthal_
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How are radio signals sent from space probes converted back into visual format?

Posted: 23 Jan 2021 06:55 PM PST

Like New Horizons or one of the Voyager spacecraft sending back a photo or video.

submitted by /u/Futomomo-senpai
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does losing a limb effect your life expectancy?

Posted: 23 Jan 2021 12:37 PM PST

saying for instance losing a arm or leg

submitted by /u/TJzzz
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Can an mRNA virus directly undergo translation in a eukaryotic cell upon infection?

Posted: 23 Jan 2021 12:18 PM PST

I'm not sure if there are intermediate steps in between to prepare the mRNA or not.

submitted by /u/Wild_Nightshade
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Can an aircraft wing or propeller cavitate like a boat propeller?

Posted: 23 Jan 2021 09:50 PM PST

What happens to the mass in a muon when it decays?

Posted: 23 Jan 2021 08:01 PM PST

Presumably the mass is converted into energy and shows up as a large jump in the kinetic energy of the electron and neutrinos.

While doing some searching on the subject no mention was made of this so I am not sure this is correct. The mass difference is pretty large between the muon and its decay products so I figured any mass to energy conversion would be dramatic and thus noted.

Another way to look at the same problem is if you were to accelerate a muon in a box and have it decay before exiting you could catch the electron and still have a net momentum gain equivalent to nearly 106 times the electrons mass. So perhaps all the energy ends up in the neutrinos as relativistic mass and we just don't detect it?

submitted by /u/zoodlebooger
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Are brain games effective?

Posted: 23 Jan 2021 09:03 AM PST

In this doucumentary https://www.imdb.com/title/tt3322570/.,

A guy sets on a journey to change imporve is brain with help of couple of scientist,first he goes by imrpoving his attention span by juggilng then he goes to next exercise called double decision .

The scientist helping with him, claims this would help a tons imrpoving certain aspect of brain.
how true is it?

submitted by /u/0xjustatech
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Do any known environmental variables impact general intelligence (g) long term?

Posted: 23 Jan 2021 02:07 PM PST

Not to confuse g with IQ - the latter is impacted by numerous environmental variables on the specific ability of a test question; the secular rise on IQ is known as the Flynn Effect, and is not on g. https://www.sciencedirect.com/science/article/abs/pii/S0160289614000105

But general intelligence. The highest domain in factor analysis of cognitive testing of ability.

I'm aware of this study temporarily raising g in kindergarten children, supposedly. https://www.sciencedirect.com/science/article/abs/pii/S0273229716300144

This study finds the heritability of g at 0.86. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4002017/

Lead poisoning does not seem to impact g. https://www.sciencedirect.com/science/article/abs/pii/S0191886918304811

So am curious, given the importance of g in our individual lives and its accounting for the IQ gaps between groups, is there evidence g may be altered negatively or positively in modern societies excepting very extreme and unlikely circumstances (such as raising children with wolves, or bodily crippling famine to the point the brain can no longer grow)? https://www.reddit.com/r/samharris/comments/hwx44l/can_we_require_sources_for_statistics_in_this_sub/fzkwpdh?utm_source=reddit&utm_medium=usertext&context=3&utm_name=askpsychology&utm_content=t3_l3fm4g

submitted by /u/measurementError
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Would Venus have ever been in the habitable zone?

Posted: 23 Jan 2021 06:59 AM PST

As the sun is ever expanding and the habitable zone moves outward, was there ever a time when Venus would have been in that zone? Further, is the zone large enough for two planets to occupy it at the same time?

submitted by /u/srocan
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What does it mean when an object is irradiated?

Posted: 23 Jan 2021 04:11 PM PST

Does this object now also emit radiation? When you hit an object with neutrons does the object then become unstable and thus becomes radioactive?

submitted by /u/ladodger22
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Saturday, January 23, 2021

Could an electric car have only regenerative brakes and no conventional friction brakes?

Could an electric car have only regenerative brakes and no conventional friction brakes?

Could an electric car have only regenerative brakes and no conventional friction brakes?

Posted: 22 Jan 2021 10:10 AM PST

My understanding is that combustion cars have brakes that turn the car's kinetic energy into heat energy, and electric cars have both these conventional brakes and can also do regenerative braking that turns some of the car's kinetic energy into electricity instead of heat. The reason they have both is that regenerative brakes can't apply nearly as much braking force as normal brakes. My question is, would it be possible for regenerative braking to be engineered to be capable of stopping a car just as quickly/effectively as conventional friction brakes can?

submitted by /u/vrama628
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Can an object ever get hotter than the thing that’s heating it?

Posted: 22 Jan 2021 10:42 AM PST

I had the hot water running on my kitchen sponge fit a couple minutes and it got really hot and got me thinking - is it possible?

Object A is a heat source heating up Object B. Under constant heat can Object B ever end up hotter than object A?

submitted by /u/PM_ME_UR_RECIPEZ
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Can a virus ever be truly airborne?

Posted: 23 Jan 2021 06:04 AM PST

With all the talks about covid being airborne, I was thinking: can there ever be a deadly virus that would survive and multiply in atmosphere like it does in a human body?

submitted by /u/Vaxis
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How do laser measuring devices have such high precision?

Posted: 22 Jan 2021 12:06 PM PST

So I just bought a laser measuring device for around $25. It seems to read down to 1/16 inch precision. Now I got curious and did the math to figure out what the round trip time for light to travel 1/16 inch and its around 1.0E-11 second. So what I am wondering is, how is that even possible to have a micro processor time something that fast. The fastest processor speed that I can find has a clock speed of around 8Ghz. Even if the cheapo components in my $25 laser measure is actually hitting those kind of speeds, the light would travel about 2 inches in one clock cycle, which would mean it could count in inches, not sixteenths. The math says it would need to be counting up around 1800Ghz to count with 1/16" precision. (a 1/16" distance equates to a 1/8" round trip, and a 900Ghz clock will have a 1/8" round trip per tick, but your precision is half your sampling speed, so you need at least double that, right? so 1800Ghz)

Is there some other principle going on than simply timing the return trip of the light? The fastest transistors that I can find are in the 300Ghz range.

submitted by /u/nathanjshaffer
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Has any research been done about the effects of the vaccine on women attempting to get pregnant?

Posted: 22 Jan 2021 12:02 PM PST

I've seen it recommended that if you are pregnant, that you do not get the vaccine during that time. As stated in the comments of this previous post: https://www.reddit.com/r/askscience/comments/k6ixqj/has_there_been_any_research_on_covid19_vaccines/

But, has there been any research about receiving the vaccine when you're attempting to get pregnant or plan to be in the near future?

The CDC's site says "Women who are trying to become pregnant do not need to avoid pregnancy after receiving an mRNA COVID-19 vaccine." with no other information. But this leads me to believe there have at least been considerations about this, but I can't seem to find any other information.

Thanks in advance.

submitted by /u/TanBurn
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If Mars needs an atmosphere to be terraformed and carbon dioxide can contribute to thickening the atmosphere, why can’t we kill two birds with one stone and ship the excess carbon dioxide from Earth to Mars?

Posted: 22 Jan 2021 10:15 PM PST

Probably a very stupid question, but it doesn't seem like we'll be making any major jumps in cleaning our atmosphere, so why not outsource it? The costs to ship the CO2 would obviously be pretty extraordinary, but we'd be preventing global warming on Earth while building another planet to one day sustain life. It can't be that easy, right?

submitted by /u/VladdyTheDaddyPutin
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How does drain unblocker gel work?

Posted: 22 Jan 2021 07:38 AM PST

How does it remove hair etc without any need for me to physically do anything?

submitted by /u/pleasant-thoughts
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Vinyl records; how can one needle pick up the vibrations of an entire orchestra?

Posted: 22 Jan 2021 01:02 PM PST

Why does it not take one groove for each instrument? I have googled it, but left-right side of the groove equals left-right channel which gives stereo does not explain to me how 2 or 10 or 50 instruments can be represented in just one groove.

submitted by /u/SnuteB
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Why would the vaccine becoming less effective be all the more reason to get the vaccine?

Posted: 22 Jan 2021 11:47 PM PST

A dip in the vaccines' effectiveness would be "all the more reason why we should be vaccinating as many people as you possibly can," Fauci added.

"Fauci: New data shows Covid vaccines may be less effective against some strains" https://www.cnbc.com/amp/2021/01/21/dr-fauci-says-covid-vaccines-appear-to-be-less-effective-against-some-new-strains.html

submitted by /u/KratomDrinker727
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will antibodies from natural infection work against the new mutations?

Posted: 22 Jan 2021 07:35 PM PST

i am aware that the vaccines work on the UK variant and maybe the others as well. i am wondering if when you originally get covid and develop antibodies will you get protected from the variants or do you 100% get reinfected?

submitted by /u/alex_gaming_9987
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Any way to tell whether a vaccinated person was previously an asymptomatic COVID-19 carrier?

Posted: 22 Jan 2021 06:29 PM PST

Prior to the vaccine, I could have done antibody testing to see if I had been an asymptomatic carrier. Since there are so many long term effects (lung ds, brain ts changes), I can see it being useful knowledge down the road.

I've now received one dose of vaccine; will we ever know if I was an asymptomatic carrier of COVID-19? Or has that ship sailed?

submitted by /u/ut_pictura
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Is associative memory the same as episodic memory? Or is there a difference?

Posted: 22 Jan 2021 03:07 PM PST

Wikipedia says it's a declarative memory and episodically based. So I was just wondering if the two names are interchangeable, or they're distinct.

submitted by /u/Dahaaaa
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Why is it that alkanes have higher enthalpies of combustion?

Posted: 22 Jan 2021 12:59 PM PST

For pentane vs pentanol, for example, this is the complete combustion (balanced to have equal number of moles of pentanol and pentane):

Pentanol: 2 C2H11OH (l) +15 O2 (g) → 10 CO2 (g)+ 12 H2O (g)+ energy

Pentane: 2 C5H12 (l) + 16 O2 (g)→ 10 CO2 (g)+ 12 H2O (g)+ energy

(Formula for enthalpy of combustion: bonds broken - bonds formed) (I think)

So since the products are the same (bond formed), then the change is at the bonds broken. From my understanding, pentane (higher enthalpy of combustion) should have less energy "wasted" in breaking bonds, as pentane's reactants should have weaker (or less) bonds.

However pentane's combustion has one extra O2 bond, so does that mean that pentanol's bonds are so much stronger (because of the OH) than pentane's to the point where even with the extra O2 molecule it takes more energy to break the bonds of pentanol's combustion rather than the bonds of pentanol's reaction?

I know that there are also incomplete combustions, but my teacher told me that just by looking at the complete combustion I should see why pentane has a higher enthalpy.

At least from my little understanding of chemistry that's the conclusion I reached but I'm not sure.

Sorry for bad English, its not my first language and sometimes I express myself unclearly.

submitted by /u/ILikeTurrttless
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How does the upward force decide if an object floats or not?

Posted: 22 Jan 2021 11:12 AM PST

So if there's a box in let's say water, there is an upward force working up on it (archimedes principle).

What my book doesn't explain, are the other pressures acting on the box. I know there's the atmoshperic pressure which is distributed through the water/liquid, but it's the same in all directions so we don't have to count it.

Does the gravitational force also have an affect on if the box floats or not on the water? What happens if the gravitational force is greater than the upwards pressure and the other way around?

submitted by /u/Peterwifebeater69
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How much soil does a tree actually consume?

Posted: 21 Jan 2021 05:36 PM PST

My sister was complaining that she can gain a couple of pounds from eating a few ounces of fudge. I told her it's not just the fudge; food combines with water when stored as fat. I then thought a good example would be a tree that consumes very little soil, but still ends up weighing many tons from the air and water it consumes.

So I would like to quantify that, but all my google searches about how much soil a tree consumes point me to articles about how much soil a tree needs to be planted in, but not how much it actually consumes.

My question is, what percentage of its weight is from air and water? Does it use anything from the soil other than trace minerals dissolved in water, that amount to only a few pounds in a mature tree?

submitted by /u/noclue2k
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vào lúc No comments:

Friday, January 22, 2021

How much energy is spent on fighting air resistance vs other effects when driving on a highway?

How much energy is spent on fighting air resistance vs other effects when driving on a highway?

How much energy is spent on fighting air resistance vs other effects when driving on a highway?

Posted: 21 Jan 2021 05:21 PM PST

I'm thinking about how mass affects range in electric vehicles. While energy spent during city driving that includes starting and stopping obviously is affected by mass (as braking doesn't give 100% back), keeping a constant speed on a highway should be possible to split into different forms of friction. Driving in e.g. 100 km/hr with a Tesla model 3, how much of the energy consumption is from air resistance vs friction with the road etc?

I can work with the square formula for air resistance, but other forms of friction is harder, so would love to see what people know about this!

submitted by /u/andershaf
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What insects/arthropods have the highest neuron counts?

Posted: 21 Jan 2021 07:16 PM PST

Tarantulas? Portia spiders? Mantis shrimp? Praying Mantises? Goliath beetles? Social insects? Social spiders?

submitted by /u/inquilinekea
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Are all stables isotopes naturally occurring?

Posted: 21 Jan 2021 02:32 PM PST

I was wondering if there are any entirely synthetic stable(i.e. non-radioactive isotopes). For instance, a stable isotope of iron that does not occur naturally but has been synthetically produced?

Edit: just noticed the title has a typo. "Stables"🤦

submitted by /u/ChaoticAnu_start
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How did the continental crust originally form?

Posted: 22 Jan 2021 03:43 AM PST

Is a crust with such extreme variation in thickness unique to Earth in the solar system? I know we have found vulcanism on other planets, but do any have continents like ours, or something analogous?

I've been wondering about this for a few days and the only thing I've come up with is that it could somehow be a result of the collision which formed the moon, but since the whole planet would have been molten I can't really see how that would work. My best guess is that the fast-spinning Earth concentrated more mass in a band around the equator which ended up going on to form the original continental crust. Obviously things would have moved around a lot since then.

Does this make any sense?

submitted by /u/Fluglichkeiten
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What causes Heisenberg's Uncertainty Principle to be true?

Posted: 21 Jan 2021 08:39 PM PST

I've seen three explanations for the reason Heisenberg's Uncertainty Principle occurs. I'm not going to iterate them because I don't want to unduly influence responses, so I'll keep it simple: why is ΔxΔp ≥ h/4π ?

Edit: why did I think momentum was rho?

submitted by /u/Downer_Guy
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Why is there doppler beaming with light when an object moves at a substantial fraction of the speed of light?

Posted: 22 Jan 2021 05:00 AM PST

Light always travels at a constant rate, so why would the rate at which at which an object approaches an observer change the brightness? Is the light more directional when an object approaches the observer at a substantial portion of the speed of light?

submitted by /u/theessentialnexus
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If quantum physics breaks down at relativistic speeds and relativity theory breaks down at the quantum level, how do high energy physicists get anything done?

Posted: 22 Jan 2021 12:44 AM PST

What is the biggest possible yield for a nuclear bomb?

Posted: 22 Jan 2021 02:02 AM PST

The biggest ever nuclear bomb, the Tzar bomba had a yield of 50 megatons. Would it be possible to build nukes in the Gigaton or even Terraton range?

submitted by /u/Adept-Matter
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Does the body naturally produce ethanol ?

Posted: 21 Jan 2021 10:20 PM PST

Does the body naturally produce ethanol in a normal setting ? And if it does what would happen if the production stopped ? Would it go unnoticed to the body ? Just asking to know if there's a secret opposite to drunkenness.

submitted by /u/Fantadialo
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Aside from Covid, are there other viruses that cause you to lose your sense of smell / taste?

Posted: 21 Jan 2021 03:00 PM PST

Adenovirus vaccines: If someone gets an Ad26 COVID-19 vaccine, does that mean any other Ad26-based vaccine will be less effective on me in the future, due to immunity?

Posted: 21 Jan 2021 02:36 PM PST

Text says most of it. I was reading that Ad26 is being used for the J&J COVID-19 vaccine because a lot of people are already partially immune to Ad5.

Will receiving an Ad26-based vaccine (for COVID-19, for example) mean that a future Ad26-based vaccine will not work as well on that same person, due to partial or full immunity to Ad26? If so, to what degree?

submitted by /u/lannister80
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What is the timeline of mRNA vaccine response?

Posted: 21 Jan 2021 09:36 AM PST

Hey! Just got my second dose so my sore arm is making me think a lot about what's going on in my body 😂 I've been doing quite a bit of reading but the one thing I can't find anywhere is the time ranges/onset of the mRNA vaccine process. For example how quickly does the cell start producing the antigen? When does it peak? When is the mRNA degraded? When is the immune response nonspecific? When does the specific kick in? Why did 2 weeks seem to be important for immunity after dose 1- is this when the memory cells are actually formed? Basically I'd love if someone could walk me through the timeline of the process!

Thanks!

submitted by /u/forgotmyact
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Do geostationary objects have no time dilation due to relative velocity differences from the perspective of the ground under them?

Posted: 21 Jan 2021 06:13 PM PST

Objects in geostationary orbit maintain a fixed distance from a point on the ground (correct me if I'm wrong). In my mind this seems to mean there is no relative velocity difference between them. Does this mean there is no time dilation due to relative velocity differences for geostationary objects from the perspective of the ground under them?

submitted by /u/jeremy210k314
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Does the edge of a galaxy have most of the young stars compared to it's core?

Posted: 21 Jan 2021 11:10 AM PST
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