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Monday, June 13, 2016

When rockets launch they must have tonnes of momentum from the earth spin and orbit. Is this used to their advantage when plotting a course?

When rockets launch they must have tonnes of momentum from the earth spin and orbit. Is this used to their advantage when plotting a course?


When rockets launch they must have tonnes of momentum from the earth spin and orbit. Is this used to their advantage when plotting a course?

Posted: 12 Jun 2016 07:26 AM PDT

Does every layer of the atmosphere have the same angular velocity as earth's surface?

Posted: 13 Jun 2016 06:26 AM PDT

By going higher in the atmosphere, gravity decreases but how does that effect atmosphere's angular velocity?

submitted by /u/theplayingdead
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Why don't dinosaur exhibits in museums have sternums?

Posted: 13 Jun 2016 06:07 AM PDT

With he exception of pterodactyls, which have an armor-like bone in the ribs.

submitted by /u/CreativeArbok
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How are large amounts of gas like Helium collected and then put into a tank?

Posted: 12 Jun 2016 08:34 PM PDT

Is the sparking that occurs when metal is put in a microwave the photoelectric effect?

Posted: 13 Jun 2016 01:51 AM PDT

If I flew away from Earth faster than light and looked back through a telescope, could I see a 'rewind' of time?

Posted: 13 Jun 2016 04:46 AM PDT

If we were to disregard the possibility of travelling faster than light and the telescope lenses needed, would it actually be possible to 'rewind' time by seeing older photons? Do you even need to travel faster than light?

Unfortunately, you'd have to travel way further than Alpha Centauri to see anything worth looking at, but theoretically it'd be pretty cool.

submitted by /u/tclemmo
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Proportionally, how much of what we see in the night sky are actually stars and how much are in fact distant galaxies that look like single stars?

Posted: 12 Jun 2016 01:39 PM PDT

How does supersymmetry work and can we measure/see the superpartners?

Posted: 12 Jun 2016 02:29 PM PDT

How does supersymmetry show itself, what suggests that it is real? And finally, the potential superpartners, are they measurable in any way and how would we know if we find them?

submitted by /u/magicpies
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Can we use giant carbon scrubbers to terraform Mars?

Posted: 13 Jun 2016 04:20 AM PDT

The martian atmosphere is composed of 95.32 percent carbon dioxide. so couldn't we build large carbon scrubbers on mars similar to the atmospheric processors in Ridley Scott's alien series? Of course you would have to warm up the planet to make it habitable, and do a bunch of other stuff. But wouldn't giant carbon scrubbers produce enough oxygen for humans to breath? 
submitted by /u/Funktapuss1324
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Why when we look at a source of light in a long distance, it looks like it is twinkling?

Posted: 12 Jun 2016 08:28 PM PDT

I'm talking about stars, street lamps, etc. If there is nothing on the way, and they are emiting light all the time, why do they spark?

submitted by /u/TheNeo0z
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How do plants protect themselves from sun damage?

Posted: 12 Jun 2016 02:22 PM PDT

What is the distribution for a set number of trials where a certain number of successes ends the trial?

Posted: 12 Jun 2016 05:27 PM PDT

For example, lets say I wanted to flip a coin 5 times, and want the probability of 3 successes, but 3 successes also ends the trial. That means there is no possibility of 4 or 5 successes. I don't think its a binomial distribution because of the restriction, but how would you calculate it?

Edit: Thanks for the answers guys! All made sense

submitted by /u/Ixionas
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[Physics] How do GPS devices compensate for perturbations in the orbits of GPS satellites?

Posted: 12 Jun 2016 04:23 PM PDT

Since the way GPS works only tells a device where it is relative to the satellites the device has to know where the satellites are, so how does it compensate for perturbations in the orbits of those satellites which make their positions less predictable especially over a long time-span?

Is station-keeping enough for that amount of precision? Do the satellites also send the parameters of their current orbit to the device?

submitted by /u/dogbreaf
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Why Do Both Fission & Fusion Release Energy?

Posted: 12 Jun 2016 12:20 PM PDT

My thinking is that they're opposites so surely they can't both release energy. I'm obviously wrong but I don't know why.

submitted by /u/Retsek860
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How can both momentum and kinetic energy be conserved is a inelastic collision in a closed system?

Posted: 13 Jun 2016 05:08 AM PDT

How does High/low blood pressure kills you?

Posted: 12 Jun 2016 11:13 AM PDT

i know it probably has something to do with tiering of the muscles needed to contract the veins but woulnd't constant train make them tougher?

Also as a secondary question, How high would blood pressure need to be for you to literally "blow up"?

submitted by /u/Jack_Harmony
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What is inflammation in the body exactly?

Posted: 12 Jun 2016 11:06 AM PDT

What is actually happening when something gets inflamed? Is all inflammation the exact same process? Do some people have a kind of chronic inflammation in their bodies due to external environmental factors like environmental chemicals or diet?

submitted by /u/TheWox
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Is there a reason that the superposition "works" in so many situations, or is the fact that so many physical properties are representable by a linear system a happy coincidence/approximation that is backed up by experiment?

Posted: 12 Jun 2016 11:16 AM PDT

Is there any reason to believe that we're simplifying things by assuming that so many properties of the universe are linear? I know that chromatic forces aren't linear, so why should so many other things be? On a personal level, it bothers me how convenient it seems. (resubmitted - the last one got blocked because it wasn't tagged)

submitted by /u/call1800abcdefg
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How precisely has the speed of light been calculated, and how?

Posted: 12 Jun 2016 10:14 PM PDT

How fast could a universe-sized black hole expand? (from xkcd)

Posted: 12 Jun 2016 09:08 AM PDT

Link: http://what-if.xkcd.com/140/

Relevant quote from the end: "But for now, at least, nearby galaxies would be safe. Since the gravitational influence of the black hole can only expand outward at the speed of light, much of the universe around us would remain blissfully unaware of our ridiculous electron experiment."

Considering that most laws of physics break down at this point, is the speed of light a law which we can count on even in this kind of scenario? Specifically, how is this different than the big bang, considering they both have similar amounts of energy, and the big bang was not bounded by the speed of light?

Or, as this is already a relatively absurd question, do we just not know enough to make an accurate guess about what would happen?

submitted by /u/0003log
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Sunday, June 12, 2016

Why isn't the radio distorted while traveling in a car?

Why isn't the radio distorted while traveling in a car?


Why isn't the radio distorted while traveling in a car?

Posted: 11 Jun 2016 11:05 AM PDT

What I mean is, why do radio waves sound the same regardless if you're moving or not?

submitted by /u/Surely_not_Nate
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Are there stars that radiate no visible light?

Posted: 11 Jun 2016 12:48 PM PDT

Do such stars exist that they radiate maybe only ultraviolet parts of the spectrum because they are so hot, or vice versa?

submitted by /u/Dirty497
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I've heard that galaxies across the universe are moving away from us at faster than the speed of light. How is this so? I thought nothing can move faster than light.

Posted: 11 Jun 2016 10:41 PM PDT

[Quantum Mechanics] How does the true randomness nature of quantum particles affect the macroscopic world ?

Posted: 12 Jun 2016 02:17 AM PDT

tl;dr How does the true randomness nature of quantum particles affect the macroscopic world?

Example : If I toss a coin, I could predict the outcome if I knew all of the initial conditions of the tossing (force, air pressure etc) yet everything involves with this process is made of quantum particles, my hand tossing the coin, the coin itself, the air.

So how does that work ?


Context & Philosophy : I am reading and watching a lot of things about determinsm and free will at the moment and I thought that if I could find something truly random I would know for sure that the fate of the universe isn't "written". The only example I could find of true randomness was in quantum mechanics which I didn't like since it is known to be very very hard to grasp and understand. At that point my mindset was that the universe isn't pre-written (since there are true random things) its writing itself as time goes on, but I wasn't convinced that it affected us enough (or at all on the macro level) to make free plausible.

submitted by /u/Drakkeur
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What element/s were present just as the big bang was about to happen?

Posted: 11 Jun 2016 01:09 PM PDT

Given that the universe is now 3/4 hydrogen but that heavier elements get fused in massive stellar objects, presumably the ultimate fusion environment was the moment before the big bang happened, or possibly in the first "split second". What element would therefore have sat at the core of it?

submitted by /u/ItsIllak
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Does time in geostationary satellites always run slower, and does special relativity ever still influence time in these satellites?

Posted: 11 Jun 2016 11:17 AM PDT

Is it solely general relativity that influences time within geostationary satellites, that are stationary to an observer on the earth, or does special relativity play a part too?

submitted by /u/Abbykiew
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When you delete something off a phone or computer, where does it actually go?

Posted: 11 Jun 2016 08:08 AM PDT

How can you put some data into a hardrive, then you can magically make it disappear for more room for data?

submitted by /u/Ammar-The-Star
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What is the difference between "apparent power" and "real power?

Posted: 11 Jun 2016 05:19 PM PDT

I know that Volt-Amperes are different yet similar to Watts and I know when one is used over the other. But what is the actual difference?

submitted by /u/roh8880
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Does material that falls from space increase Earths gravitational pull?

Posted: 11 Jun 2016 10:01 PM PDT

I read that around 37000-78000 tons of material falls to Earth every year. Sense the Earth is 4.5+ billion years old, would all that material that falls to Earth every year increase earths gravitational pull?

submitted by /u/Youre_A_Wizardqwert
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Why is visible light limited to such a small fraction of the electromagnetic spectrum?

Posted: 12 Jun 2016 06:53 AM PDT

Like the title asks, if the electromagnetic spectrum ranges with waves from picometers to thousands of kilometers long, why can we only see around the 1 μm band?

I'm interested in this from a physics rather than biological perspective (though biological explanations would be welcomed), since most biological vision systems seem to work in this range. What special properties exist in this band that makes it so suitable for vision, which other frequencies/wavelengths do not share?

submitted by /u/mehum
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Do animals have meal times?

Posted: 11 Jun 2016 06:19 AM PDT

Obviously wild animals are restricted by when they come up on food (and when the food is doing their easily huntable thing) and most domesticated animals are fed at interval by humans. I'm wondering if given an abundance of food do animals have a tendency to graze or do they seem to eat at the same time each day? I'd guess it would change by species but if others have more definitive answers, greater trends, or even answers about specific species I'd love to be informed about them.

submitted by /u/colgaf
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How do cities without bodies of water/rivers nearby deal with sewage? Examples: Johannesburg, South Africa or Lodz, Poland.

Posted: 11 Jun 2016 10:52 AM PDT

Why do unusually tall people (7' or above) tend to have medical issues such as heart problems and bone problems?

Posted: 11 Jun 2016 10:05 AM PDT

Suppose you throw a coin an infinite amount of times. What are the chances that an infinite streak of heads is going to come up?

Posted: 11 Jun 2016 07:48 PM PDT

My intuition says that it would be a 100% chance, but then, it would also mean there's also a 100% chance of an infinite streak of tails, and those two couldn't be both true at the same time... Could they? Would it actually be a 50/50 chance for both of them then? I really have no idea.

submitted by /u/rafabulsing
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Do different kinds of light travel it different speeds?

Posted: 11 Jun 2016 05:14 PM PDT

You know, inferred, blacklight, etc.

submitted by /u/MyNameIsBing
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What molecular signal initiates the physiological process of muscular hypertrophy?

Posted: 11 Jun 2016 09:56 AM PDT

As I understand it, muscular hypertrophy revolves around the concept of progressive overload and micro trauma: essentially, one damages the muscles by heavily exerting them and they repair themselves to handle a stronger load (thus increasing in size) and one must exert them more/with more weight to cause them to undergo growth instead. What signal is it that detects micro trauma and causes hypertrophy to occur, and what protein pathway cascades during the process of hypertrophy? In other words, what exactly is happening in a muscle at the molecular level when it grows?

submitted by /u/Jnicky69
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What are the four new elements and their functions?

Posted: 11 Jun 2016 06:41 AM PDT

Chemistry noob here. I read that Japan names one of the new found elements Nihonium. There are also Moscovium, Tennessine and Oganesson. What are their (potential) functions and how are new elements discovered?

submitted by /u/korovasynthemesc
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Why are the changes between states of matter binary? How come water is liquid at 0.1 degree Celcius, but suddenly turns to solid at 0 degree Celcius; why is there no intermediate state?

Posted: 12 Jun 2016 03:50 AM PDT

It just seems too arbitrary to me. The molecules behave one way in this temperature, and suddenly they behave in a totally different way just by removing 0.1 centigrade.

Why doesn't it, for example, turn into a thick paste which gets thicker and harder the colder it gets?

submitted by /u/clickstation
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[Mathematics] What is the practical value of prime numbers and uncovering their properties?

Posted: 11 Jun 2016 01:29 PM PDT

how do wild animals remove porcupine quills?

Posted: 11 Jun 2016 11:31 PM PDT

Is the graphical fidelity of games limited by computational power available currently or is it very difficult to make a realistic looking game?

Posted: 11 Jun 2016 11:35 AM PDT

If the resources were available to run it, could a game that looks like real life be made?

submitted by /u/thatCamelCaseTho
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Does the nutritional makeup of a green banana change when it becomes ripe?

Posted: 11 Jun 2016 04:13 AM PDT

After a banana becomes very ripe it looks, smells and tastes so different. Do the caloric, carbohydrate or nutritional amounts change at all?

submitted by /u/steegie
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Why are allergies far more common in developed countries?

Posted: 11 Jun 2016 03:02 AM PDT

I've been to a lot of poorer countries and allergies there usually unheard of but otherwise extremely rare. I thought it could be due to lack of diagnoses but even where the healthcare systems are pretty good it's still extremely rare. I know the number of people who die of allergies in developed countries is extremely low but it seems there's far more people whose lives are affected by it. Do we know why this is the case?

submitted by /u/ivandelapena
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Saturday, June 11, 2016

Does a person using a skateboard expend less energy than a walking person traveling the same distance?

Does a person using a skateboard expend less energy than a walking person traveling the same distance?


Does a person using a skateboard expend less energy than a walking person traveling the same distance?

Posted: 10 Jun 2016 07:01 PM PDT

Yes, I know. Strange question. But I was watching a neighbor pass by my house on a skateboard today, and I started wondering about the physics of it. Obviously, he was moving between points A and B on his journey faster than he would be walking. But then again, he also has to occasionally use one foot to push against the ground several times to keep the momentum of the skateboard moving forward at a higher speed than if he was just walking.

My question is basically is he ending up expending the SAME amount of total energy by the "pushing" of his one foot while using the skateboard as he would if he was just walking the same distance traveled using two feet?

Assume all other things are equal, as in the ground being level in the comparison, etc.

My intuition says there is no such thing as a "free energy lunch". That regardless of how he propels his body between two points, he would have to expend the same amount of energy regardless whether he was walking or occasionally pushing the skateboard with one foot. But I'm not sure about that right now. Are there any other factors involved that would change the energy requirement expended? Like the time vs distance traveled in each case?

EDIT: I flaired the question as Physics, but it might be an Engineering question instead.

submitted by /u/FalconAF
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Can liquid water exist on planets with extremely high gravity?

Posted: 10 Jun 2016 07:11 PM PDT

Can water exist in its liquid state on a planet like Jupiter, or does its extremely strong gravity compress it down somehow?

I was thinking of this in the context of which exoplanets could host life, which as far as we know requires liquid water. Would the physical systems that make life on earth possible be able to function on a planet with extremely high gravity, or do they become too "smushed" down?

submitted by /u/Eveverything
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Why does anxiety cause digestive issues?

Posted: 10 Jun 2016 09:10 PM PDT

How was the number of atoms in a mole calculated?

Posted: 10 Jun 2016 10:02 PM PDT

How was Avogadro's number discovered and measured?

submitted by /u/Sword_and_Scholar
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What did mathematician Ron Graham mean by saying that the number 2^120 is "beyond what computers can do; no computer can do 2^120 things right now" ?

Posted: 10 Jun 2016 05:06 PM PDT

I've recently been reading about Graham's number and decided to watch a few YouTube videos. This one, with him explaining it, is what I'm referencing in the title.

How do we measure the total power of computers? And how would we go about doing that at any given time?

submitted by /u/shrugsnotdrugs
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Is there any reason to rule out the possibility of multiple universes separated by distance?

Posted: 10 Jun 2016 06:52 PM PDT

Similarly to how we have multiple galaxies separated by distance. Obviously, it's impossible to actually verify, but is there any reason to believe that there do not exist other universes some unknown distance away from the edge of our observable universe?

I suppose, for the sake of discussion, I'm defining "universe" to be a physical grouping of galaxies similar to our own universe.

submitted by /u/DFAnton
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If time is sped up with gravity, then shouldn't the black hole that formed with our galaxy already have undergone Hawking radiation?

Posted: 11 Jun 2016 01:51 AM PDT

From the perspective of the black hole, time farther away from it would seem like a stand still. Much like in the movie, "Interstellar" where one hour on the planet orbiting a black hole equals 7 Earth years.

Now, I understand that it takes a very very very long time (10100 years) for a black hole to undergo Hawking Radiation, but shouldn't the relativity of time inside the event horizon be exponentially sped up compared to time experienced on Earth?

Wouldn't this make it so that Sagittarius A* would have already gone through all those years through time dilation and no longer be there?

submitted by /u/m2themichael
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How is parental DNA analysis performed?

Posted: 10 Jun 2016 08:44 PM PDT

I was explaining to a co-worker how DNA historical analysis is accurate for fathers but not for mothers of an individual. I have been lead to believe that it is the haploid sperm cell that carries the mitochondrial gene that is used for parental analysis.

I was unable to clarify further than that, and I was wondering if I was incorrect or how I could further clarify my statement.

Thank you.

submitted by /u/Soulcraver
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How do blood clots pass through the blood brain barrier?

Posted: 10 Jun 2016 09:42 PM PDT

I thought that the blood brain barrier filters out large molecules. So wouldn't a clot be way large enough to be filtered out? Am I simplifying this too much or is there more to the brain blood barrier that I do not know.

submitted by /u/michealcaine
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How do people with cerebral palsy and similar neurological disorders still retain neural plasticity?

Posted: 10 Jun 2016 07:25 PM PDT

What method is better for survivability when jumping off a building? Landing with a mattress or landing on a mattress?

Posted: 10 Jun 2016 08:44 PM PDT

Can ionizing radiation knock an electron out of one atom and into another?

Posted: 10 Jun 2016 09:11 PM PDT

Can radiation expel an electron out of the 'orbit' of one atom and into another, and would this electron then become part of that atom?

Could it potentially collide with a proton, and what would happen if it did?

submitted by /u/Latexfrog
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If I were to extrude a perfectly straight bar, would it go around the Earth or out to space?

Posted: 10 Jun 2016 11:57 AM PDT

Let's propose we have a fantastical material that doesn't bend, stretch, compress, shear, whatever. I have a machine which if I were to point directly up, would extrude a continuous bar of material straight up.

If I position it parallel to the ground, would the extruded bar wrap around the surface of the planet, as gravity warps space so as to be flat all the way around, or would it eventually leave the atmosphere due to the relative curvature of the Earth?

submitted by /u/Dzugavili
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Is a carbon molecule C=C=C=C... possible?

Posted: 11 Jun 2016 02:49 AM PDT

I was reading about carbon nanotubes and graphene and thought that surely a single atom diameter strand of carbon would be even stronger.

submitted by /u/sum_force
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Can I get intoxicated by smelling alcohol?

Posted: 10 Jun 2016 04:55 PM PDT

What happens to the DNA in transplanted organs?

Posted: 10 Jun 2016 11:21 AM PDT

I understand that cells are replaced as they die and all tissues and organs are eventually entirely replaced. Does the amount of cells in the donor organ that has the DNA of the donor stay the same through the lifetime of the recipient?

There must be some transition point between donor and recipient tissue, right? What happens at that point at a cellular level?

submitted by /u/Tril0bite
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Can you harness the heat and friction from the brakes of a car to charge a battery in an electric car?

Posted: 10 Jun 2016 04:35 PM PDT

Where is our solar system "going"?

Posted: 10 Jun 2016 12:44 PM PDT

I have a few questions about our solar systems orbit;

  • Our solar system is part of the Milky Way - what are we orbiting around exactly?
  • Are we moving towards anything or is every objects distance and orbit constant?
  • Will we come closer to other systems/stars/objects or even a chance we will ever run into other bodies?
  • Will our orbit ever be affected by other stars or celestial objects?
  • Will our orbit ever collapse?
  • Are we moving through space like a frisbee or on an angle?

Thanks in advance!

submitted by /u/mysteryslice
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If I have a cup of coffee with cream, drink half the contents, refill it with only black coffee, and repeat infinitely, will there ever be zero cream in the cup?

Posted: 10 Jun 2016 01:42 PM PDT

Assume this is a homogenous solution. I drink the same amount each time and refill to the same level each time. I know the cream will eventually be a negligible amount but will it ever be gone completely?

submitted by /u/DoctorScrambles
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Why do some animals eyes glow when they look into a camera, but not people?

Posted: 10 Jun 2016 02:19 PM PDT

Light Thrust?

Posted: 10 Jun 2016 07:08 AM PDT

This is my first question in AskScience so forgive me if its been asked before. My question pertains to the properties of light, particularly its very special property of always finding the shortest travel distance. Why does this happen ? Also, I was just pondering ideas about how no object can attain the speed of light. However, is it possible to use light itself as mechanism of thrust? Realistically this doesn't seem possible to me because light is somewhat mass less and am unsure if it would even produce a force.

submitted by /u/0shocklink
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