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Friday, June 19, 2020

Are there gemstones on the moon?

Are there gemstones on the moon?


Are there gemstones on the moon?

Posted: 19 Jun 2020 05:54 AM PDT

From my understanding, gemstones on Earth form from high pressure/temperature interactions of a variety of minerals, and in many cases water.

I know the Moon used to be volcanic, and most theories describe it breaking off of Earth after a collision with a Mars-sized object, so I reckon it's made of more or less the same stuff as Earth. Could there be lunar Kimberlite pipes full of diamonds, or seams of metamorphic Tanzanite buried in the Maria?

u/Elonmusk, if you're bored and looking for something to do in the next ten years or so...

submitted by /u/reidzen
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How much did fishes adapt to fishing?

Posted: 19 Jun 2020 03:23 AM PDT

We as humans practice fishing for a very long time, and very intensively recently, so I wonder how can fishes still got tricked by the hooks and baits (even though most of fishing today is not with that method) So, are there fish species that significantly changed their behavior in response to fishing? And which one?

submitted by /u/Sabanoob
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If something bleaches, where does the colour go?

Posted: 19 Jun 2020 07:52 AM PDT

When something gets bleached, where does the colour go? For example plastic toys or printed posters that lose their colour when exposed to the sun, as well as chemical bleached things such as hair or fabrics.

submitted by /u/crybabymoon
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What mediates a salmon's ability to return to it's home river?

Posted: 18 Jun 2020 08:46 PM PDT

Is the instinct to return to their home river encoded in their DNA, or in their early memories? For example, if I took salmon eggs laid in river A and transplanted them in river B, which river would they return to?

submitted by /u/summer-the-puppy
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How does the doppler effect not violate conservation of momentum? Is this a dark energy, negative vacuum pressure thing?

Posted: 19 Jun 2020 08:12 AM PDT

Not a physics major. Just watch a lot of Matt O'Dowd(👍).

Photon momentum is a function of frequency. If a photon's frequency is different between two observers in receding galaxies, where did that momentum energy go?

Does it bleed into some fundamental field? Does dark energy's stretching of spacetime warp the waveform? Does it mean there really is a prime reference frame and photon energies are only observed to be different because of relativistic Doppler effects?

submitted by /u/Semi-Pro_Biotic
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Could there be new Covid-19 symptoms that haven’t surfaced yet?

Posted: 19 Jun 2020 07:27 AM PDT

For example, could we be in a "stage 1" of this virus? Is it possible that as of right now, the coronavirus is entering "stage 2" and surprising our immune systems, or some other symptom that just hasn't surfaced yet? What are the chances of new symptoms arising that we haven't seen yet?

submitted by /u/gwk326
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can space really be called a vacuume?

Posted: 19 Jun 2020 02:53 AM PDT

If i'm understanding solar wind correctly space shouldn't be considered a true vacuum right? what am i missing here?

submitted by /u/jjversesub
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Questions on Newton's 3rd law: when I push on a wall, how does it push back on me? I just don't understand what is happening at the particle level when push a wall thar causes it to push back on me. Same goes with an object on a table, how does the table actually push back on the object?

Posted: 18 Jun 2020 04:20 PM PDT

When does a human become capable of recognizing their own reflection?

Posted: 18 Jun 2020 08:39 AM PDT

As the question suggests, I'm just curious on how and when a person starts to recognize themselves in a mirror, and how does it compare to animals, for example?

submitted by /u/thehariharan
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Does the engine placement on a plane affect how steep the plane can take off?

Posted: 18 Jun 2020 07:58 PM PDT

I know there are a lot of factors involved in this such as the wind, weight of the plane, and the design of the plane itself but imagine two planes, one with engines on the tail (MD-80 series) vs. one with engines on the wings (737s or A320s), taking off at an identical takeoff situation. Which plane might be able to take off at a steeper angle?

submitted by /u/MinntyFr3sh
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Since heat transfer is caused by random collision of particles, is it mathematically possible that your hand could touch a hot pan and you actually heat up the pan with your hand?

Posted: 18 Jun 2020 11:47 AM PDT

I know the probability of this would be inconceivably small so it would never actually happen, but is it mathematically possible that: because heat transfer is based on random collisions of particles, all the hot particles just so happen to bounce from your hand to a hot so that the net heat transfer is positive? This would mean that instead of the pan heating up your hand, your hand transfers even more heat to the pan.

Sorry if I'm misunderstanding physics, just a fun question I thought of.

submitted by /u/achappy808
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What kingdom or domain of life are viruses in, and what differentiates them specifically from other single-cell organisms like bacteria?

Posted: 18 Jun 2020 10:58 AM PDT

I was doing some reading for fun on this and I can't find them anywhere in the Taxonomy wikipedia(https://en.wikipedia.org/wiki/Taxonomy_(biology) page

submitted by /u/KomraD1917
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How fast could you go if you built a railgun straight through the Moon?

Posted: 19 Jun 2020 12:10 AM PDT

If the Moon is 3500Km's across and assuming that you had 200Gw available (1Gw nuclear plant every 100Kms with efficiency losses) and 1 ton of mass? How does this change at a limited acceleration of 10g? I think that you would get to a decent percentage of c but I don't know what this would be.

submitted by /u/CastiloMcNighty
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If gravity propagates non-instantly, does that mean planets are being pulled to where the sun *was* a small time ago?

Posted: 18 Jun 2020 07:34 AM PDT

If so, since the sun is moving extremely quickly through the galaxy, why doesn't it eventually lose its planets as they're in a sense being attracted to a point pretty far "behind" where it currently is?

submitted by /u/blablatrooper
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Does docking with the international space station affect its orbit?

Posted: 18 Jun 2020 12:36 PM PDT

I would imagine it would have to - what I'm really curious about is whether or not it is enough of an impact that an adjustment has to be made after docking in order to keep the ISS in a stable orbit

submitted by /u/DrAbro
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How did covid-19 enter the first person to infect them?

Posted: 18 Jun 2020 09:15 PM PDT

From what's all understanding I have, it would be unlikely that the first case was from someone eating a bat. Is it that maybe it comes from something else they had eaten that was infected?

submitted by /u/Comput3rn3rd
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Are there any "living clades" (2 or more species whose last common ancestor is not extinct)?

Posted: 18 Jun 2020 04:55 AM PDT

I can't think of any... it could happen, right?

Oh and "living clade" is apparently a meaninglyes term that I've just made up, which is probably why I can't google it! And maybe I'm using it wrong anyway, unless I'm also going to insist that ALL the descendents of the last common ancestor are still with us. I would settle for any pair of distinct species who share a common ancestor that is not extinct.

submitted by /u/steady_pair_of_hands
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Plasmonic virus sensing: Seriously, why isn’t this more common?

Posted: 18 Jun 2020 04:02 PM PDT

This technique has been around since about 2010 (source) and has seen publications in ACS as recently as April (source). As someone who has colleagues working on similar techniques, why haven't I seen anything about this being applied in practice?

submitted by /u/spacepbandjsandwich
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Why is it easier to hold your balance on a bicycle going fast than a bicycle going slowly?

Posted: 18 Jun 2020 08:22 AM PDT

When you are going a down a hill - you gain a lot of momentum, why is it that when in a state of higher momentum the chances of you falling off are considerably less because it's much easier to hold your balance than it is going at a slower pace: why is this?

submitted by /u/xXStyler
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Why do people vomit from drinking banana and sprite?

Posted: 18 Jun 2020 12:44 PM PDT

Why are Irradiated Objects Radioactive for so Long??

Posted: 18 Jun 2020 06:19 AM PDT

I'm watching the Chernobyl docuseries for the first time and am not fully grasping the concept of radiation exposure.

It seems that a lot of the land around Chernobyl has seen reduced radiation over time to where tourists can come and visit the area (for limited periods of time).

But the Pripyat Hospital basement is still incredibly dangerous from the piles of engineer and fireman clothes who were working that night some 30+ years ago.

There are even videos on YouTube - https://youtu.be/pzjtJNu-jYM - of people touring the basement with Geiger counters, showing the radiation being emitted from those items.

Please explain to me like I'm a 6 year old:

  • Why/how do irradiated objects then themselves emit their own radiation? (if that is even what is happening)
  • Why are objects/soil on the surface (that were in close proximity to the core explosion) seemingly "safer" 30+ years later, while worker's clothes are still dangerous?
  • Is there a simple way to explain radiation and its effects in high doses (more so on objects than people)?

Thank you.

submitted by /u/lipmonger
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Thursday, June 18, 2020

How do almost extinct species revive without the damaging effects of inbreeding?

How do almost extinct species revive without the damaging effects of inbreeding?


How do almost extinct species revive without the damaging effects of inbreeding?

Posted: 17 Jun 2020 12:40 PM PDT

I've heard a few stories about how some species have been brought back to vibrancy despite the population of the species being very low, sometimes down to the double digits. If the number of remaining animals in a species decreases to these dramatically low numbers, how do scientists prevent the very small remaining gene pool from being damaged by inbreeding when revitalizing the population?

submitted by /u/Bac2Zac
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Crows are all over the world, but where are crows naturally from and what kind of effect did they have as an invasive species?

Posted: 18 Jun 2020 07:44 AM PDT

A short time ago I saw an eagle flying around and I was in awe of it's beauty because it's such a rare sight here, but then a murder of crows started chasing after him and eventually wore him out and got him.

Then I started to wonder how eagles even exist if 6 crowd can so easily take one down, and there are so many crows around.

I think I heard once that ravens are originally from Northern America and that they've been spiritual animals for some Native American cultures, but I could be wrong about that.

So could it be that crows have only been in Europe and Asia for a couple hundreds of years? If so, how devastating was their arrival to the local bird population and other animals?

submitted by /u/DuploJamaal
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How fast does electricity travel via USB?

Posted: 18 Jun 2020 05:38 AM PDT

For example you have a gaming controller connected via wire to a console or PC. How fast is the electricity traveling? Would it still be close to speed of light?

Does changing the wiring in such short cable matter? For example if you switch to fiber.

submitted by /u/MrBlooregardQKazoo
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Why exactly do we ever need to assume the Axiom of Choice, if it doesn't even tell us how to construct the relevant sets? What practical results need this axiom?

Posted: 18 Jun 2020 03:57 AM PDT

How quickly does a person infected with a virus become infectious themselves?

Posted: 17 Jun 2020 03:33 PM PDT

Current times got me thinking... If there were a stadium with 50,000 people in attendance for 2 hours and one of them had a virus and was infectious, presumably that person would infect a number of people around them. But how quickly would those newly infected people become infectious themselves? By the end of the 2 hours, how many of the 50,000 would we expect to be infected?

submitted by /u/koftechameleon
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Is there any way to know what the Earth's rotational speed might have been prior to the collision with Theia that is theorized to have formed the Moon? And is there any chance the Earth ever experienced tidal locking/synchronous rotation with the Sun?

Posted: 17 Jun 2020 03:34 PM PDT

I've seen writing that suggests that the Theia may have significantly increased the speed of the earth's rotation. Is there any chance that the Earth was ever tidally locked to the Sun before that collision? Do models of the collision include an ability to estimate the earth's angular velocity prior to impact?

submitted by /u/gibbous_waning
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Alright here me out, a theoretical balloon that will never pop and just keep stretching, what happens if you fill it with air and take it into space?

Posted: 18 Jun 2020 01:02 AM PDT

Earth’s escape velocity is 11 km/s. What happens if we are slower than that?

Posted: 17 Jun 2020 08:45 PM PDT

Why can't a craft slower than that escape earth's gravity. What happens if we try?

submitted by /u/kashewnut
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How long (in distance) is twilight?

Posted: 17 Jun 2020 11:37 AM PDT

How far from east to west does twilight stretch at any one time? Let's say, at the equator.

Thanks in advance for your answers.

Praxis

submitted by /u/Praxisinsidejob
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Did the nuclear bomb (testing) and the subsequent increase in background radiation levels lead to an increase in cancer?

Posted: 17 Jun 2020 11:36 AM PDT

I found out today that some experiments require low-background steel, i.e. steel forged before the nuclear bomb, as steel forged after this period is contaminated with airborne radionuclides. This led me to wonder whether the increase in background radiation had an appreciable effect on cancer rates in the global population, but I couldn't find any information on this.

submitted by /u/KingOfTheAlpacas
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How does sonar work?

Posted: 17 Jun 2020 03:21 PM PDT

I get that sonar is a device that emits sound waves and then collects their reflection and records the time taken in order to calculate the distance an object is from the source, but how does the device ensure that it will collect the sound wave upon reflection. For example if there was a smooth plane in front of the emitter, only a couple sound waves would return to the emitter upon reflection. Also how does a sonar distinguish one emitted wave from another?

submitted by /u/Shadowmancer1
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When ice is melting on thin water why does it rotate slowly?

Posted: 17 Jun 2020 09:47 AM PDT

Example is here: link

For some reason, it just doesn't sit still while melting, and something causes it to spin ever so slowly.

submitted by /u/oi_peiD
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When was the concept of "zero gravity" in space discovered, and was it immediately related to mass?

Posted: 17 Jun 2020 10:02 AM PDT

Perhaps this is a melding of r/askscience and r/askhistory, but I was curious when the concept of Zero-G, or microgravity, came to be discovered or understood, and whether it was immediately correlated with the presence of mass.

submitted by /u/The--Strike
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How does a polarizing light microscope work?

Posted: 17 Jun 2020 12:01 PM PDT

I understand how the polarization works. I'm more confused on the ordinary/extraordinary waves that are produced after the plane polarized light passes through the material. (Side question: I still can't wrap my head around isotropy/anisotropy if someone could also explain that.) I don't understand how the second polar causes the extra/ordinary waves to create the vibrant colors in PLM or how rotating the stage causes the visible wavelength to cycle. Thank you in advance.

submitted by /u/ngogos77
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Why is random noise incompressible?

Posted: 17 Jun 2020 07:42 AM PDT

I was looking up whether it is possible to have an incompressible sequence. I came across this post in which people are saying that random noise is incompressible: https://stackoverflow.com/questions/9185289/uncompressable-data-sequence

 

However, if I came up with a random sequence of numbers I would be able to encode the data in fewer bits by recognising patterns in the data, say multiple 1s or 0s in a row. My compression algorithm could record this section of data as 'n' number of zeros, instead of writing them all out.

submitted by /u/AchillesFirstStand
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Does severity of infection affect a person’s ability to donate convalescent plasma?

Posted: 17 Jun 2020 10:04 AM PDT

I've just had a serological antibody test performed by my workplace for SARS-COV-2, despite never having shown symptoms for the illness. I had hoped to be able to donate plasma if I came up as positive, however in reading the donation guidelines for convalescent plasma however the criteria specifically state they require the donor to 'have fully recovered from the infection and have a confirmed diagnosis of COVID-19.'

I think I'm mostly getting hung up on the verbiage used but wanted to confirm: Does presence of antibodies in plasma itself act as confirmation that a person has experienced an infection? If so, does the severity of that infection somehow affect the efficacy of donor plasma?

submitted by /u/zytz
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What's the Difference Between Receptors and Transporters?

Posted: 17 Jun 2020 09:51 AM PDT

I've been looking into the mechanism of actions of psychiatric medication and have found they primarily affect neurotransmitter transporters such as DAT, NET, and SERT. I've also found some psychiatric medication affect serotonin receptors like 5-HT1, adrenergic receptors, and dopamine receptors like D2 and D3.

What's the difference between monoamine transporters and receptors? How do some medications only affect receptors and not transporters? What functions do receptors fulfill that transporters do not?

submitted by /u/scr00ge_
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Is there a minimum or maximum limit to the wavelength of gravitational waves? What kind of gravitational interactions could these correspond to?

Posted: 17 Jun 2020 12:41 PM PDT

How do we determine the "handedness" of a race track?

Posted: 17 Jun 2020 06:18 AM PDT

When going out for a bike ride on the roads, it's usually better to pick a clockwise loop to minimize the number of left-hand turns. However, riding my bike on the local F1 track (Circuit Gilles-Villeneuve) got me wondering how we would determine the handedness of a closed loop like a racetrack. Is it about the number of turns? About how long you go in a given direction? I would assume that this is greatly affected if the race track crosses itself too?

submitted by /u/Kerguidou
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After recovery from COVID-19, does repeated exposure continue to build and prolong resistance?

Posted: 17 Jun 2020 10:40 AM PDT

Wednesday, June 17, 2020

Why does a web browser require 4 gigabytes of RAM to run?

Why does a web browser require 4 gigabytes of RAM to run?


Why does a web browser require 4 gigabytes of RAM to run?

Posted: 16 Jun 2020 08:41 PM PDT

Back in the mid 90s when the WWW started, a 16 MB machine was sufficient to run Netscape or Mosaic. Now, it seems that even 2 GB is not enough. What is taking all of that space?

submitted by /u/profdc9
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Ask Anything Wednesday - Economics, Political Science, Linguistics, Anthropology

Posted: 17 Jun 2020 08:08 AM PDT

Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Economics, Political Science, Linguistics, Anthropology

Do you have a question within these topics you weren't sure was worth submitting? Is something a bit too speculative for a typical /r/AskScience post? No question is too big or small for AAW. In this thread you can ask any science-related question! Things like: "What would happen if...", "How will the future...", "If all the rules for 'X' were different...", "Why does my...".

Asking Questions:

Please post your question as a top-level response to this, and our team of panellists will be here to answer and discuss your questions.

The other topic areas will appear in future Ask Anything Wednesdays, so if you have other questions not covered by this weeks theme please either hold on to it until those topics come around, or go and post over in our sister subreddit /r/AskScienceDiscussion , where every day is Ask Anything Wednesday! Off-theme questions in this post will be removed to try and keep the thread a manageable size for both our readers and panellists.

Answering Questions:

Please only answer a posted question if you are an expert in the field. The full guidelines for posting responses in AskScience can be found here. In short, this is a moderated subreddit, and responses which do not meet our quality guidelines will be removed. Remember, peer reviewed sources are always appreciated, and anecdotes are absolutely not appropriate. In general if your answer begins with 'I think', or 'I've heard', then it's not suitable for /r/AskScience.

If you would like to become a member of the AskScience panel, please refer to the information provided here.

Past AskAnythingWednesday posts can be found here.

Ask away!

submitted by /u/AutoModerator
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Why doesn't the Banach-Tarski theorem work in the physical world?

Posted: 17 Jun 2020 12:07 AM PDT

The theorem would have you believe you can violate conservation of mass with an Exacto knife. Why is this untrue, what's different about the physical world that doesn't apply to the Banach-Tarski theorem?

submitted by /u/corgocracy
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How are nerve agents such as Novichok so lethal? How does such a small amount of vapour spread in the body?

Posted: 16 Jun 2020 01:50 PM PDT

In beta decay, how does a neutron turn into a proton, accompanied by an electron and a positron? In addition, why does having extra neutrons make the atom unstable?

Posted: 17 Jun 2020 07:33 AM PDT

I have 2 main problems/questions I'm struggling to understand.

  1. Why is the positron necessary? Why would you need a positron when charges of proton + electron = neutron ? Is it because of the spin, or something that I need to balance out?
  2. Why does the decay happen in the first place? Why is having 2 extra neutrons (in carbon 14) be a such a big deal?

+ Additional Question: What makes the C14 atom go, "Let's change one of our neutron instead of getting rid of 2 neutrons and turning into C12"?

To sum it all up, what's a beta decay?

Thanks in advance!

submitted by /u/-TheRightTree-
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It doesn't mention in the article, but would we have an understanding of what triggers the change in the spike to emerge from under the stealth glycan coating? Would it be opportunistic, with only spikes in proximity to a target cell emerging or a global reaction on the virus surface?

Posted: 17 Jun 2020 06:10 AM PDT

https://phys.org/news/2020-06-sugar-coating-coronavirus-infection.html

It doesn't mention in the article, but would we have an understanding of what triggers the change in the spike to emerge from under the stealth glycan coating? Would it be opportunistic, with only spikes in proximity to a target cell emerging or a global reaction on the virus surface?

"Amaro is a corresponding author of a study published June 12, 2020 on bioRxiv.org—an open-access repository of electronic preprints—that discovered a potential structural role of the shielding glycans that cover the SARS-CoV-2 spike protein. "You can see very clearly that from the open conformation, the spike protein has to undergo a large structural change to actually get into the human cell," Amaro said.

But even to make an initial connection, she said that one of the pieces of the spike protein in its receptor binding domain has to lift up. "When that receptor binding domain lifts up into the open conformation, it actually lifts the important bits of the protein up over the glycan shield," Amaro explained."

submitted by /u/Self-Existent_X
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Why does the bone density of astronauts drop when they spend the better part of the year in space? How is the bone density recovered once on earth? I saw Col. Chris Hadfield mention it in an interview.

Posted: 16 Jun 2020 09:05 PM PDT

How is CPU or GPU usage calculated and reported? How does a piece of hardware "know" how much of its maximum processing capacity is being utilized?

Posted: 16 Jun 2020 04:23 PM PDT

Why is it that protons, neutrons, electrons, atoms, and quarks are all depicted as spherical? Are they actually spherical in real life or are they just drawn that way? If they are actually spherical in real life why is that the case?

Posted: 16 Jun 2020 06:54 PM PDT

How accurate are Punnett Squares from high school biology in describing genetics?

Posted: 16 Jun 2020 06:16 PM PDT

Can someone recover from an asymptomatic case of COVID-19?

Posted: 16 Jun 2020 11:04 PM PDT

Could convalescent plasma be used as a vaccine instead of a treatment?

Posted: 16 Jun 2020 09:18 AM PDT

Say I got covid, could I just give my Grandparents (or yours) plasma before they get it? Could they then give plasma to their friends and so on?

submitted by /u/localhelic0pter7
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Why do planetary gears rations not seem to follow the normal rear reduction rules?

Posted: 16 Jun 2020 08:03 PM PDT

No idea if this is the correct sub for this but I figure it cant hurt to ask. I'm pretty good with physics and science IMO and I figured for fun I'd try to teach myself about planetary gearboxes because they're pretty cool and a bit more complicated than regular gears.

So I 3D printed a little gear I made with a 60 tooth ring gear, with a 30 tooth sun gear and two 15 tooth planet gears. When you do the math for this particular gearbox (using equations I found online), it says for one full rotation of the sun gear, the planets should move about 1/3 of the way around the circle, essentially a 3:1 reduction, and this is how it works with the model I printed; but I'm having trouble wrapping my head around where the 3 comes from.

I would think that if I spin the sun gear one full rotation (30 teeth) it would force the planets to also spin a distance of 30 teeth, or half way around the circle. But when you look up close you can see that with one full rotation of the sun gear, 20 teeth mesh between the sun and the planet, getting us the 20/60 or 1/3 rotation that the equations predict. So obviously the math is right and I am just visualizing it wrong. I can see if I instead twist the ring and watch the center gear it will twist twice to the outer gears one turn, which makes sense in my head for the two to one. So really what still doesn't make sense is where the 3 to 1 comes from when you hold the ring gear stationary and drive the sun. Can anyone explain why its not working the way my head seems to think it should work? Or is this there a better sub to ask?

Here are some pictures if necessary

submitted by /u/millerp513
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How do we know the layers of the earth?

Posted: 16 Jun 2020 07:37 PM PDT

How? I know we haven't drilled down to the core. I know we have volcanos so that would tell us that at least the next layer is molten, but how do we know the rest? Also the temperature? How do we know the composition of the different layers?

submitted by /u/Ever-Wandering
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Why do estimations of how much sea level will rise after all the ice melts vary so widely?

Posted: 16 Jun 2020 01:25 PM PDT

Is COVID still considered a respiratory disease?

Posted: 16 Jun 2020 07:26 AM PDT

I read somewhere that COVID is not actually a respiratory disease, but a virus that attacks blood vessels. Also, that when transferred through the air the virus attacks the lungs cause lungs have blood vessels. Not sure about how true this is, I wanted confirmation.

submitted by /u/TurquiseBird
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What happens when a lightning strikes the sea?

Posted: 16 Jun 2020 01:26 AM PDT

Oldest evidence for freshwater life?

Posted: 16 Jun 2020 09:58 AM PDT

I've been trying to get a handle on when life began to move from the oceans to freshwater, as opposed to land, but can't seem to find more than the oldest evidence for a specific type of life in a particular location, for example crayfish in Australia.

It seems to me that the transition to freshwater would have been easier than that to land, and likely earlier, but it may be that fossils are less easily preserved in rivers, lakes and streams. Does anyone know or have any pointers to the evidence for the earliest colonisation of freshwater environments?

submitted by /u/Perspicacia_Tick
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What is the latency of the eye?

Posted: 16 Jun 2020 02:50 AM PDT

When the eye sees an image, how long does it take to reach the brain? It might take longer or shorter for some people to perceive the stimulus (based on the speed of their reflexes), but how long does it take for the information to reach the brain from the eye?

submitted by /u/MetricSystemAdvocate
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If sound travels faster through denser materials and slower through less dense materials, than how come helium, which is less dense than air, makes the voice higher, while sulfur hexaflouride, which is denser than air, makes the voice lower?

Posted: 16 Jun 2020 11:52 AM PDT

What happens with rearranged intestines? Does it change anything afterwards?

Posted: 15 Jun 2020 10:57 PM PDT

After surgeries where they have to move around the intestines/take them out temporarily, are they just shlopped back in? Is there a way to put them back like they were? Would this later affect digestion or anything?

submitted by /u/Tolfvinc
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