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Sunday, December 31, 2017

If the Niagara falls is frozen where does all the water go behind it? Does it just spill over and flood surrounding land

If the Niagara falls is frozen where does all the water go behind it? Does it just spill over and flood surrounding land


If the Niagara falls is frozen where does all the water go behind it? Does it just spill over and flood surrounding land

Posted: 31 Dec 2017 03:23 AM PST

Why is/was there a tendency for like minerals to collect together on earth?

Posted: 30 Dec 2017 08:20 AM PST

It seems that the original source for minerals was random and that they should be randomly, and relatively homogeneously spread over the surface of the earth. Yet minerals like iron oxide, sodium chloride, gold, silver, (and most others it seems) have had a significant tendency to be found concentrated in various areas, making mining them and collecting them a practical endeavor.

What has caused that to occur?

submitted by /u/mspe1960
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If future data from the LHC and ILC suggest that our universe is metastable, what does that mean for the future of the universe?

Posted: 31 Dec 2017 05:01 AM PST

1) What does "metastable" mean in comparison to unstable and stable? Why is this related to the properties of the Higgs Boson and Higgs Field?

2) If it is metastable, what kind of event could cause it to suddenly want to seek a lower energy state?

3) How fast would this "new physics" bubble expand once it reached a lower stable energy level?

4) Would this be compatible with life chemistry as we know it? If the bubble hit Earth, would we just simply stop existing?

Bonus Question: If the Higgs Field were to simply disappear in an area of space, would W+, W−, and Z bosons become massless and completely change the weak force? Does this have anything to do with a vacuum metastability event?

submitted by /u/Stuck_In_the_Matrix
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When heavier elements undergo fusion do they release more energy?

Posted: 31 Dec 2017 12:44 AM PST

Not actually sure if heavier elements can fuse without extreme conditions, but what would happen if heavier elements instead of smaller ones like hydrogen were fused? Since our sun releases energy this way could a star of heavier elements release more energy?

submitted by /u/Carconzo222
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Since a particle that interacts with the Higgs Field only gets a portion of their mass from it, can there exist a particle that has mass but does not interact with the Higgs Field?

Posted: 30 Dec 2017 10:29 PM PST

Is their a limit to the amplitude of a light wave/ is their a limit to how intense a light source can be?

Posted: 31 Dec 2017 12:23 AM PST

Is there scientific backing to vibrational "healing"?

Posted: 30 Dec 2017 01:10 PM PST

I would love to see from a physics standpoint how vibrations/frequencies/waves from things like music or anything in general have a positive or negative effect on our bodies. I'm skeptical, but would be very interested to know if there is a connection.

submitted by /u/jennyo120
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Is there a relationship between the amount of energy an isotope emits when it decays and its half-life?

Posted: 30 Dec 2017 05:20 PM PST

I spent a while trying to figure this out, but was unable to come to any conclusion. Different isotopes release different amounts of energy when they decay, and the amount of time it takes to decay can vary significantly, but is there a good way to estimate how radioactive something is with only knowledge of the half life OR energy emitted per decay? Elements with shorter half lives are pretty much always more radioactive than their longer lived counterparts, but that's entirely because the atoms are releasing energy much more frequently, rather than releasing more energy in total. Is it possible to have an isotope with an extremely short half life that is fairly safe because its radioactive decay releases very little energy?

I wasn't really sure if this is physics or chemistry, so I apologize if this was miscategorized.

submitted by /u/TheDubiousSalmon
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The least-intuitive question in physics: how does gryoscopic precession work? (e.g. Helicopter Blades)

Posted: 30 Dec 2017 11:45 PM PST

This isn't a casual question for me, it's something I've tried to understand for some time now. Not sure what concept I'm missing.

But the outright weirdness of how gyroscopes work still bugs me, the fact that placing a torque on a gyroscope produces a force that is 90° off-axis is freaking bizarre, and I'm not the only one that thinks so!

Does anyone, anyone have a great explanation for how this concept works?

Here's a video by Veritaseum if anyone wants an introduction to the problem:

https://www.youtube.com/watch?v=ty9QSiVC2g0

submitted by /u/Anenome5
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Why is there a critical spreading rate for epidemics in random networks while the spreading rate in scale-free networks are irrelevant for epidemics?

Posted: 30 Dec 2017 12:36 PM PST

Hi, Im a little bit confused after I read a paper* about the network topology and how they influence speading of diseases. My basic understanding was that there is reproduction rate (R) and the critical reproduction rate is 1. If R<1 then the disease will eventually die, but if R>1 then the disease will grow and eventually contaminate everyone in the network.

Can someone explain me why the spreading rate in scale-free networks is irrelevant, but relevant in random networks? I didnt quite understand the explaination by the authors.

Source: *Pastor-Satorras, Romualdo;Vespignani, Alessandro (2001): Epidemic Spreading in Scale-Free Networks, in: Physical Review Letters, 86 (14), 3200-3203

submitted by /u/Fotm_Abuser
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(Stone) statue and radiation?

Posted: 30 Dec 2017 11:29 AM PST

Recently I took a tour of the UN in New York, and they had a statue (made of stone, I presume, but I'm not sure) on display that was in Japan during the Nagasaki bombing. The back part of it had melted off due to it. The statue was fully exposed, with no glass casing or anything, so I was concerned whether it was safe to display like that since it had been exposed to so much radiation. Would something like this contain/emit a harmful amount? (pic for reference)

submitted by /u/anacldgmz
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What does the G tense in the Einstein field equation stand for and why does it have two other variables assigned to it?

Posted: 30 Dec 2017 08:52 AM PST

I recently encountered the field equations of Einstein as I was inquisitive about the expansion of the universe. Unfortunately for me I dont have an in-depth of physics (yet). I am a high school student. I was able to understand most of the variable components of the formulae but I have trouble understanding the G and T tenses of the formulae. Would love to get an explanation for this. Thank you for your time.

submitted by /u/the_rman
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How does the falcon heavy have nearly double the payload to gto than the delta 4 heavy, a rocket just as big that doesn’t have to save feud in its first stage for a return trip?

Posted: 30 Dec 2017 11:35 AM PST

Why is the useful life of a smoke detector only 10 years?

Posted: 30 Dec 2017 08:00 AM PST

Given the half-life of the radioactive source is FAR greater than that, shouldn't these work for far longer (barring other causes of failure)? Or have smoke detectors been engineered to perform within specific tolerances for only 10 years (i.e. planned obsolescence)?

submitted by /u/psyop63b
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How do marine mammals (especially whales) become trapped in seasonal polynyas?

Posted: 30 Dec 2017 04:45 AM PST

Having recently watched a sequence covering whales trapped in polynyas in an episode of the BBC's 2001 "Blue Planet" series entitled "Frozen Seas" I became curious to know how mammals (particularly whales) became trapped in them? Having searched online a bit I found little information about the development of this type of a situation.

submitted by /u/Creativation
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Are there any theorized particles that existed only in the electroweak epoch?

Posted: 29 Dec 2017 09:33 PM PST

My current understanding is that at the beginning of the universe, at least two forces, the electromagnetic and the weak force, were under the right conditions to be considered a single force.

Are there are particles, akin to what a photon is to the electromagnetic force, that exist only in a merged electroweak force?

submitted by /u/Slayton101
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Does thrust and acceleration affect the body (or other objects) in space?

Posted: 30 Dec 2017 07:23 AM PST

The question comes from a novel series I've read (the Expanse). In the series, they mention that at faster/higher thrust speeds, they have to have crash couches and drugs to handled the force of the thrust. When near a planet or star, that would make sense. But, if you're out in deep space with zero gravity, would you feel it if a ship had a sudden or constant acceleration? I would think in a zero gravity environment, you wouldn't feel the thrust. Or, you might feel an initial "bump" since the ship begins to travel before you do, but it would settle very quickly. Love the series, but that part bugs me when I read it.

submitted by /u/mal_reynolds_
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Saturday, December 30, 2017

Is it possible to navigate in space??

Is it possible to navigate in space??


Is it possible to navigate in space??

Posted: 30 Dec 2017 03:52 AM PST

Me and a mate were out on a tramp and decided to try come up for a way to navigate space. A way that could somewhat be compered to a compass of some sort, like no matter where you are in the universe it could apply.

Because there's no up down left right in space. There's also no fixed object or fixed anything to my knowledge to have some sort of centre point. Is a system like this even possible or how do they do it nowadays?

submitted by /u/hazza_g
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The heisenberg uncertainty principle and quantum physics are interesting-- but how is it confirmed?

Posted: 29 Dec 2017 02:22 PM PST

The way I understand one -aspect- of the heisenberg uncertainty principle is as such-- A neutron, for instance, is 'not in a single location, rather has distinct probabilities of various locations until it interacts with another object'-- I may be butchering the science, as I am but a humble student, but how can we say something like this with a rational scientific mindset? Is it not more reasonable to conclude that we simply don't -know- its' location until it's 'interacted with something? Or is there something i'm missing here?

submitted by /u/AnalysisHero
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What are real-life applications to fractional and higher-order (specifically of degree 3+) derivatives?

Posted: 29 Dec 2017 03:00 PM PST

I found this intriguing because the 4th, 5th, and 6th time-derivatives of displacement are snap, crackle, and pop, respectively--those names sound like they lack practical importance (apart from the cereal joke), at least to someone inexperienced like me.

submitted by /u/ThompsonChess
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How were they able to continue to operate Reactors 1-3 after the Chernobyl disaster?

Posted: 29 Dec 2017 09:30 AM PST

After the Chernobyl disaster there were still 3 reactors that were operable and remained in operation for years afterwards. I'm not familiar with nuclear power plants, but I would assume that their operations are somewhat similar to other plants like refineries and chemical plants. You have to have operators in a control room, operators making rounds in the "field," and a maintenance crew to perform routine maintenance on the equipment.

So, how was the staff able to continue working at the site when the city had to be deserted due to the radiation?

submitted by /u/Trbvmm
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Why is the speed of light expressed as 'c'?

Posted: 29 Dec 2017 01:38 PM PST

If A Railgun Fired in Space, Would There Be Recoil?

Posted: 29 Dec 2017 08:33 AM PST

I understand that the force applied to the projectile follows the "right hand rule", and by Newton's third law I know that for every action there is an equal and opposite reaction, but does this apply to electromagnetic forces?

Would a Railgun therefore require stabilizing thrusters if it was in space? (No matter how tiny the projectile, I imagine that eventually it would be off stable orbit)

submitted by /u/xzieus
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Does giving blood change your vascular system?

Posted: 29 Dec 2017 08:09 AM PST

Hi,

I give blood regularly and I've noticed, probably just like many others, that giving blood gets easier with time. Which made me wonder about three things:

  • is it due to a significant change in my vascular system?

  • does that mean if I get hurt I'll be more likely to have a haemorrhage?

  • what could be, if any, the other changes in my body due to giving blood

Thanks!

submitted by /u/Vaglame
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How quickly does our body identify nutritious intake of substances?

Posted: 29 Dec 2017 05:54 AM PST

Think of when you're a bit hungry, and you eat a PB-jelly sandwich. The (slight) hunger goes away quite quickly, but I imagine the digestion process takes quite some time. What if I ate indigestible food with the same texture that my body couldn't break down? Could I fool my belly/brain?

How does our body regulate hunger and how quickly and accurately can it do it actually?

submitted by /u/hldshflskdhfsdlh
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How large would an asteroid need to be to be visible by the unaided eye in the night sky and has this happened?

Posted: 29 Dec 2017 08:26 AM PST

Assuming it is within 150km as it passes Earth

submitted by /u/Apatharas
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Eureka moments; what are they, really?

Posted: 29 Dec 2017 09:09 AM PST

When we read or hear about the famous 'light bulb' moments in science, are these sparks of new insight from genius minds or are they the moments when thoughtful people, after lengthy study and pondering, finally understand something fundamental about a known or theorized concept?

submitted by /u/abracusaurous
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Is the entire atmosphere of ice and gas giants opaque?

Posted: 29 Dec 2017 07:06 AM PST

I've read descriptions about what it would be like to fall onto Jupiter's "surface" but none of them talked about what a human would see. Since the gaseous part of the atmosphere is mostly hydrogen and helium, both colorless gasses, I imagine that once you get through the upper clouds you can start to see what you're falling into.

As far as I know, there is no liquid layer even in the ice giants. It just is a gas that slowly gets more and more dense until it's "basically" a liquid and then "basically" a solid. But why would this state of matter be opaque? After a certain point falling into Jupiter, for example, couldn't you start to see light from the extremely hot core/metallic hydrogen?

Or is it that like how water appears clear, but after a few miles of it no visible light gets through?

submitted by /u/Sexual_Congressman
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Other than water and salt, are there any products that we eat which have absolutely no biological origin/ingredients?

Posted: 29 Dec 2017 01:53 PM PST

Water is a naturally occurring chemical, and so is salt. Neither of these products necessarily need to come from an animal or plant, or any other organism. They are not living, and do not come from anything that has lived.

Are there ANY other products that we can (and normally do) eat, that are like this?

submitted by /u/-popgoes
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What would happen if the ballast tanks on a ship were a vacuum?

Posted: 29 Dec 2017 04:28 AM PST

Would the ship sink, float or capsize?

submitted by /u/hendo_1337
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How does rain affect airplane drag and lift?

Posted: 29 Dec 2017 09:18 AM PST

How do laser pointers damage the human eye?

Posted: 29 Dec 2017 05:35 AM PST

Why do the pictures on thermochromic mugs fade in from bottom-to-top?

Posted: 29 Dec 2017 04:26 AM PST

Why do the pictures on thermochromic mugs appear from bottom to top, like in this video?

I thought maybe it was because in the video it was filled but slowly. So I just tried it with my own mug and filled it up quickly to the top, and saw the same slow bottom-to-top fade. Is there some effect which causes the bottom of the mug to heat faster than the upper parts?

submitted by /u/talminator101
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[Biology] Among people without chronic eye conditions, how much variance is there in the highest wavelength of light they can 'see'?

Posted: 29 Dec 2017 08:12 AM PST

Online sources report that a typical person can see light in the wavelength range 390nm-700nm.

I'm interested to know how consistent those limits are from individual to individual, among people with generally good eyesight.

Just as some individuals have exceptional eyesight (as good as 20/10, 'twice' as good as 20/20), are there individuals that can perceive 740nm wavelength light, or 770nm? And are there individuals that lack the ability to perceive 660nm wavelength light?

submitted by /u/sirgog
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Fukushima : How does "radiation cleanup" work exactly ? What are the metrics ?

Posted: 29 Dec 2017 07:07 AM PST

Prompted by this article

edit : corrected link

submitted by /u/Neker
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Friday, December 29, 2017

Can temperature affect the speed of electricity? And if so can extreme temperature, hot or cold, completely stop the electric current through something? Power lines, electronics, etc.

Can temperature affect the speed of electricity? And if so can extreme temperature, hot or cold, completely stop the electric current through something? Power lines, electronics, etc.


Can temperature affect the speed of electricity? And if so can extreme temperature, hot or cold, completely stop the electric current through something? Power lines, electronics, etc.

Posted: 29 Dec 2017 05:29 AM PST

Just curious if extreme cold but also extreme heat can affect the speed of electricity through something..? I've seen when it is extremely cold my phone appears "laggy" is this do to the cold on its processor? And also can extreme temperatures affect power lines and things of that sort?

submitted by /u/StrongSpicyBoi
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What's the difference between antibiotic, antiseptic and anti-bacteria?

Posted: 29 Dec 2017 05:52 AM PST

In cultures where people file their teeth, are there higher rates of tooth decay due to removed enamel?

Posted: 29 Dec 2017 01:19 AM PST

How are very accurate shunts calibrated?

Posted: 29 Dec 2017 12:21 AM PST

For example if I go buy a shunt calibrated to measure accurately to 100ppm(0.01%). The person selling it to me has to have one more accurate?

And if I want one accurate to 10ppm(0.001%), the seller needs one more accurate to verify 10 ppm, but how does he calibrate the one that is being used to calibrate?

Where does it stop and how?

submitted by /u/Mr-Dogg
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How do trees survive freezing temperatures? Does the water in them not freeze?

Posted: 28 Dec 2017 02:45 PM PST

How will the current injection of excess CO2 into the atmosphere affect the eventual coldening due to the Milankovitch cycles?

Posted: 28 Dec 2017 03:36 PM PST

How does a computer know how much is 1 second?

Posted: 28 Dec 2017 02:16 PM PST

When standing on a frozen pond or lake is it the intramolecular forces of ice or the buoyancy of the ice on top of the water that are supporting you?

Posted: 28 Dec 2017 11:12 AM PST

*intermolecular thanks u/WeepingSeepage

submitted by /u/Typical_mann
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If the barrels of guns weren't rifled, would there be more or less ricochet?

Posted: 28 Dec 2017 04:43 PM PST

Why does Water turn white when it is foam ?

Posted: 28 Dec 2017 07:56 PM PST

When water turns into foam (for example at waterfalls, behind a boat etc.) then it always appears white, but why is that so ?

I knkw that there are millions of bubbles in the water at that state, but why does it cause it to turn white and not stay transparent ?

submitted by /u/AlienKatze
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How do scientists measure temperatures upwards of billions of degrees Celsius?

Posted: 28 Dec 2017 08:57 AM PST

Related Reddit post

The article linked in the reddit post is wrong in some places, but it states that the largest recorded temperature of matter is on Earth, and it is 4 trillion degrees Celsius. A quick Google search confirms the fact that the largest recorded temperature is on Earth, but the temperature is in fact 5.5 trillion degrees Celsius, as recorded by the scientists working at the LHC (Large Hadron Collider). What I want to know is: how do those scientists record the temperature of such particles?

submitted by /u/iTitan_Extreme
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Why are rechargeable versions of AA/AAA 1.2V instead of 1.5V?

Posted: 28 Dec 2017 10:53 AM PST

I was looking at some rechargeable batteries and they all said they were only 1.2V. I realise they work in my devices, but is that 0.3V difference not a problem?

submitted by /u/Money_on_the_table
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How did 1I/2017 U1 'Oumuamua get 'ejected' from it's home solar system?

Posted: 28 Dec 2017 07:09 PM PST

I have read all about how 1I/2017 U1 'Oumuamua is the first confirmed extrasolar object, and why it is indeed extrasolar and that it must have been 'ejected' from its original solar system. But I haven't read anywhere how that happened. I am not an orbital mechanics expert, but it seems to me that it is highly improbable that any object could reach escape velocity and trajectory from its original gravity well at an arbitrary moment in time. I mean, doesn't the law of conservation of energy on an object in an elliptical orbit require the application of an external force? We have been studying asteroids and comets in our own solar system for a long time now and (I believe) we have never spotted one that wasn't on an elliptical orbit. My only guess is that 1I/2017 U1 is the survivor of a supernova, but strange that no commentary has ventured a guess on this one.

submitted by /u/rpbsjy
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Why does toothpaste become hard and dry when exposed to air?

Posted: 28 Dec 2017 04:10 PM PST

I'm sure this can be applied to other substances (Cremes, ... ) as well.

submitted by /u/LeftistLittleKid
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What does the content of radioactive waste Disposal Containers (The yellow ones) look like?

Posted: 28 Dec 2017 03:58 PM PST

How do I simply explain the forces involved with the sedimentation of solids in juice?

Posted: 28 Dec 2017 10:19 AM PST

I'm editing a paper from someone who is not a physicist (food science), I'm not a physicist (flair), and the people who are going to read this paper will predominantly not be physicists (commercial juice industry and other food scientists), but I'd like to make sure this one sentence is as technically accurate as possible.

The following sentence is trying to explain how, all other things being equal, larger particles suspended in fruit juice tend to settle more quickly than smaller particles:

The larger the particles, the bigger the gravitational force, thus the easier to precipitate.

I have edited it to read:

The more massive the particle, the larger the gravitational attraction, thus accelerating the rate of sedimentation.

Aside from drag, is gravity the only force at work here and is my correction technically accurate?

submitted by /u/Griegz
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The Large Hadron Collider can allegedly reach 4 trillion Kelvin, is this theoretical, are there repercussions of producing that heat?

Posted: 28 Dec 2017 09:15 AM PST

Why do planes need to be defrosted?

Posted: 28 Dec 2017 11:56 AM PST

I understand they have moving parts that need to be able to move in order to take off. But surely the same risk would be present if descending and landing somewhere cold like Norway. Would the heat of engines not stop components from freezing, even when taxi-ing?

submitted by /u/jackh1990
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