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Sunday, July 2, 2017

Are there any other animals known to "work out", or do an activity for the sole purpose of muscle growth?

Are there any other animals known to "work out", or do an activity for the sole purpose of muscle growth?


Are there any other animals known to "work out", or do an activity for the sole purpose of muscle growth?

Posted: 01 Jul 2017 03:06 PM PDT

How is the analog signal from a HDD read head processed before it is digitized?

Posted: 01 Jul 2017 08:38 AM PDT

Doing a simple estimation, a hard drive might be able to read 128 MB/s. Maybe it has 4 platters, giving each read head a reading speed of 32 MB/s, or 256 Mbit/sec. So this would be a 256 MHz signal coming from the read head, but of course it's not a clean digital signal. Some of the magnetic domains might have lost some of their alignment making their signal weaker, and in any case everything would bleed together a bit, right?

What does the signal from the read head look like, and how is it processed to become digitized?

Furthermore, how does the HDD even know where the read head is in terms of the circumference of the platter?

submitted by /u/tpk5
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On an infinite square grid of perfect one Ohm resistors, what is the equivalent resistance between two points that are a knight's move from each other?

Posted: 01 Jul 2017 02:46 PM PDT

Relevant XKCD

I've been reading XKCD for years at this point, and I like looking into things that appear in the comics. What is the resistance here, how would you work it out, and why is it so incredibly hard?

submitted by /u/MrAcurite
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How does the internal body maintain a temp of 37 (98.6F) degrees Celsius without difficult yet any temperature over, say, ~26 (~80F) degrees Celsius is seemingly hot and causes a sweat (cooling) response in most, despite the internal temperature being much higher?

Posted: 01 Jul 2017 11:39 AM PDT

How can scientists measure the electron affinity and the ionization energy of an element?

Posted: 02 Jul 2017 02:14 AM PDT

I am pretty curious about the method that the scientists use to measure the electron affinity and the ionization energy of an element. If someone knows about it, please tell me.

submitted by /u/Keddongy
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What adaptations would reef organisms have had to survive past climate conditions (e.g., in the Cretaceous) when atmospheric carbon dioxide levels were much higher than they are today?

Posted: 02 Jul 2017 05:16 AM PDT

Considering the concerns regarding the impact of ocean acidification on the abilities of organisms that build calcium carbonate skeletons, I have often wondered what adaptations might such organisms have had in the distant past when atmospheric CO2 was considerably higher than it is today? Are there living species that are largely unaffected by such effects?

submitted by /u/mynameismrguyperson
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How does gravity shift wavelength for light emitted at non-radial directions and for observers located at finite distance?

Posted: 01 Jul 2017 08:10 PM PDT

The only equations I could find for gravitational redshift assumed that light was emitted radially, directly outward from the mass and that the observer was located infinitely far away from it and any other masses. How would this change if the light was emitted at a different angle or if the observer was still within the mass's gravitational field?

submitted by /u/Platyturtle
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How does the VASIMR rocket engine not destroy itself?

Posted: 01 Jul 2017 10:22 PM PDT

http://www.adastrarocket.com/aarc/VASIMR

This engine may power our spacecraft one day, and I understand the gist of it except for this: "ICH is a technique used in fusion experiments to heat plasma to temperatures on the order of those in the Sun's core (10 million K)". The Museum of Flight, where I learned about the engine today, said something similar. How can heat of that incredible magnitude be produced in any machine without destroying it in an inferno? Are there materials or construction methods that could actually withstand such temperatures?

submitted by /u/Reverie_39
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Scientist are capable of artificially creating temperatures of near 0k, how are these temperatures measured?

Posted: 01 Jul 2017 05:57 PM PDT

How do submarines cause cavitation on their bodies/propellers and what exactly does it do to the metal?

Posted: 01 Jul 2017 10:46 PM PDT

I'm trying to get an in-depth but idiot-readable explanation of Cavitation

What causes it, what it does and how it affects life underwater in a submarine

So I can help the developers of the game Subnautica understand cavitation and therefore fix their game

submitted by /u/pm_me_ur_diapergirls
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How does laser strength fall off with distance?

Posted: 01 Jul 2017 11:02 AM PDT

Normally, light follows the inverse square law when it comes to intensity, but lasers are very concentrated so it takes a longer time for this law to take significant effect. What I want to know is when/where this transition is and how the signal strength can be modeled before and after it.

submitted by /u/Platyturtle
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[Computer Eyestrain] Is there a difference between using a blue-light filtering software on the computer, and tinted computer eyeglasses that claim to do the same, assuming the screen is non-reflective matte?

Posted: 01 Jul 2017 12:10 PM PDT

If the boiling point of water is 100°C, why is gaseous water present in the air at room temperature (~26°C)?

Posted: 01 Jul 2017 05:41 AM PDT

Question says it all. If the temperature at which water becomes a gas at 100°C, how is it possible that it is still in a gaseous state at room temperature and it doesn't just condense in the air?

submitted by /u/D_H_M_O
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How does using an attenuated/inactivated vaccine with someone infected with rabies help?

Posted: 01 Jul 2017 05:43 AM PDT

I understand these vaccines will familiarise the immune system with the virus and therefore cause a quick immune response the next time the person is infected, but if the person has already been infected, won't the vaccine just have the same effect on the immune system as the actual infection? Wouldn't it make more sense to inject them with antibodies?

submitted by /u/smrnnm
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How come crocodiles were able to survive the K-T extinction event but no land-based dinosaurs were?

Posted: 01 Jul 2017 06:57 AM PDT

How did we go from unicellular to multicellular life?

Posted: 30 Jun 2017 10:45 PM PDT

Is fat burned during or after exercise?

Posted: 30 Jun 2017 11:34 PM PDT

I know excersizing burns fat, but does it occur while you're excersizing or does it take place afterwards?

submitted by /u/proudwhytetrash
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Euler's identity in non-euclidean euclidean geometry?

Posted: 01 Jul 2017 03:46 PM PDT

What happens with Euler's identity in non-euclidean geometry?

submitted by /u/Untrahaer
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How do we know that The Speed of Light is the speed limit of the universe?

Posted: 01 Jul 2017 08:37 AM PDT

Saturday, July 1, 2017

There are thousands of seemingly isolated bodies of water all throughout the planet which happen to have fish in them. How did they get there if truly isolated?

There are thousands of seemingly isolated bodies of water all throughout the planet which happen to have fish in them. How did they get there if truly isolated?


There are thousands of seemingly isolated bodies of water all throughout the planet which happen to have fish in them. How did they get there if truly isolated?

Posted: 30 Jun 2017 10:27 AM PDT

How are black/white photos colorized?

Posted: 30 Jun 2017 07:38 AM PDT

I think the post is pretty clear... How to people colorize black and white photos with such accuracy and stuff?

submitted by /u/texzone
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Was there an evolutionary advantage to different hair colors in humans?

Posted: 30 Jun 2017 06:11 PM PDT

Basically what the title says, and I know how different hair colors are a result of different proteins and melanin, but how do the did the different range of colors help humans in earlier time periods adapt to their environments and have higher survival rates?

submitted by /u/dizzyoak1
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Does writer's block have a neurological foundation?

Posted: 30 Jun 2017 06:43 AM PDT

I'm just wondering if anyone has brain-scanned someone suffering from writer's block. Can you see a downturn in the various language areas of the brain? Is it a measurable phenomenon or is it one of those "too-subjective-to-be-measured" things?

submitted by /u/chorjin
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Can you train your memory to be better? If so, is there any limit to how far you can take it?

Posted: 30 Jun 2017 05:28 PM PDT

If someone trained their whole life would they have near-photographic memory?

submitted by /u/PhosBringer
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How powerful is the laser in a typical fiber optic cable?

Posted: 30 Jun 2017 07:11 PM PDT

Just want to know in Watts the approximate power of a laser in a fiber optic cable that would be used for something like internet providing or similar fiction. If possible the input strength and output strength, say over 10 meters.

submitted by /u/hisnameislongarms
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Why are we so much more likely to stumble in a stalled escalator than in regular stairs?

Posted: 30 Jun 2017 09:13 PM PDT

Do bird's nests get reused?

Posted: 30 Jun 2017 05:22 PM PDT

I watched some birds grow from eggs tohatchlings and, now that they are gone, I am hoping they will come back next year. Do birds ever reuse their nests?

submitted by /u/Batman_is_Bateman
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Why is it that so many seemingly unrelated languages have raised tone at the end of a sentence denote an interrogative?

Posted: 30 Jun 2017 03:10 PM PDT

If languages evolved separately, why do they all contain this particular quirk? In almost every single language I've come into contact with, raising your tone at the end of a sentence means that you're asking a question.

submitted by /u/rks-
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What's the significance of oxidation number in a covalent bond? Are the electrons shared, or aren't they? (rephrased my awkward question from yesterday)

Posted: 30 Jun 2017 03:09 PM PDT

I am trying to understand the REASON for the following:

Valence count - assume all electrons are shared equally Formal charge - assign one half of bonding electrons to each atom Oxidation number - assign all bonding electrons to the most electronegative atom None of these is actually true, but each gives a quick approximation that is useful for a particular type of problem. 

https://chemistry.stackexchange.com/questions/13827/how-is-the-charge-of-covalently-bonded-atoms-determined

submitted by /u/thefourthchipmunk
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During beta decay, when a neutrino and a beta ray are created, where does it's mass come from?

Posted: 30 Jun 2017 05:09 PM PDT

How is the Moon covered mostly fine dust if the erosion forces of wind, water, and plate tectonics do not exist?

Posted: 30 Jun 2017 07:01 AM PDT

If I remember right there was a point where the moon had mildly active plate tectonics (correct me if I'm wrong), but I still don't understand what other than meteor impacts could cause any erosion on the surface, let alone enough to make a fine dust.

Also on a side note, I know that relative to Earth meteoroids are called meteors when traveling through the atmosphere and meteorites when they've impacted the ground, but how should they be referenced in relation to the moon since it has no atmosphere?

Edit: Despite proofreading my post I still have a typo in my title. Frick.

submitted by /u/DBudders
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ARC - A nuclear fusion reactor from MIT smaller and cheaper than ITER - a year has passed and no one talk about it. Why?

Posted: 30 Jun 2017 10:52 AM PDT

Why dont plants suffer from the effects of aging and cancers like mamals do?

Posted: 30 Jun 2017 04:39 AM PDT

So bare with me its been a while since my last biology class.

If the semi-conservative replication of DNA causes degredation over time which leads less and less acurate copies of DNA strands is attributed with causing the visable effects of aging, and higher occurances of cancers.

Then how can plants such as redwood trees live for hundreds of years with out simply dying of old age ?

submitted by /u/VPope
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Nuclear fission and fusion have been explained to me as "opposites." Why do they both produce energy?

Posted: 30 Jun 2017 02:11 PM PDT

Using QFT or String Theory, why would an electron be attracted to/more likely to exist around positive charges such as protons?

Posted: 30 Jun 2017 10:29 AM PDT

If we consider particles to be an excited state of a field or string, why would they exhibit an attractive force toward another wave?

submitted by /u/Gonzobean7
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Friday, June 30, 2017

Why does catnip have such an intoxicating effect on cats and do we know what they're experiencing?

Why does catnip have such an intoxicating effect on cats and do we know what they're experiencing?


Why does catnip have such an intoxicating effect on cats and do we know what they're experiencing?

Posted: 29 Jun 2017 07:38 PM PDT

I just watched my cat have a catnip trip and I wanted to know what it was like for her and how it happens

submitted by /u/i_fight_rhinos2
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What happens when lightning strikes in an ocean?

Posted: 29 Jun 2017 09:05 AM PDT

Knowing that water is a conductor (and salt too?) how far would an electric current be carried through an ocean? Would the electricity just fizzle out after a certain distance or would it keep traveling until it hit an insulator?

submitted by /u/Gunsmith49
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Are there auditory illusions in the same way that there are optical illusions? If so, what are some examples and how do they work?

Posted: 29 Jun 2017 09:04 AM PDT

Why is it that when we fall asleep on our own, our time asleep feels longer than when we are put under anesthesia and the time passes what seems instantaneous?

Posted: 29 Jun 2017 07:55 AM PDT

Why do our eyes get "bags"?

Posted: 29 Jun 2017 08:39 PM PDT

When a government or company wants to launch a new satellite, how do they know its orbit won’t make it crash into another satellite? Is there some kind of universal database that shows where everything is up there?

Posted: 29 Jun 2017 11:01 AM PDT

How can superconducting transformers transform steady DC voltage/current?

Posted: 30 Jun 2017 02:36 AM PDT

How come space rockets (Falcon-9, Ariane 5, etc...) don't have fins on them? What keeps them stable in flight?

Posted: 29 Jun 2017 08:04 AM PDT

Here is a picture of Falcon-9 and Ariane 5.

As you can see there don't seem to be any apparent fins on either of the rockets. So how do these rockets remain so stable?

submitted by /u/Akuba55
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Are there significant and recognizable differences between the structure of most plant and animal genomes?

Posted: 30 Jun 2017 06:31 AM PDT

What are dreams exactly?

Posted: 29 Jun 2017 08:31 PM PDT

I have a some more questions that extend from this main question and I just want to know as much as I can.

What causes them? Why can I clearly remember some and others not at all? Why can I control some and others my mind is tricked even if stuff makes no sense? Why can you have nightmares?

Thank you for any replies.

submitted by /u/SpyroThunder
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Why do the storms on Jupiter and Saturn last much longer than storms on Earth?

Posted: 29 Jun 2017 05:56 PM PDT

Could we create a space Crane on the moon?

Posted: 30 Jun 2017 04:30 AM PDT

I know that currently we do not have the materials to create a tether that can run from the earth to space to create a space elevator. Could we do it on the moon?

submitted by /u/shambol
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How does diet affect the risk of heart disease?

Posted: 30 Jun 2017 08:15 AM PDT

There is a lot of conflicting information out there. The common story is that (saturated) fat and cholesterol in meats are the primary culprits, but now a lot of (pop) science seems to claim that those are relatively harmless and sugars are instead the main culprits. What does the actual scientific evidence support?

submitted by /u/ProfThrowaway17
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What exactly is AI?

Posted: 30 Jun 2017 04:29 AM PDT

Is artificial intelligence a computer or something else? Stated differently, could you have a regular computer one day like an iPhone, then the next day get nothing more than a software update and have AI on the same phone? Or would there need to be different hardware installed?

submitted by /u/Coloneldave
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What size of antenna would be required in another solar system to receive radio or tv signals from earth?

Posted: 29 Jun 2017 07:26 PM PDT

Let's say I'm on an earthlike planet orbiting Proxima Centuri or some other close star... what would I need to pick up TV or Radio signals?

submitted by /u/usernameicanremember
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If we could dig a hole deep enough that the heat was enough to convert water to steam, could we produce an endless supply of power by harnessing that steam?

Posted: 30 Jun 2017 02:25 AM PDT

I'm making a couple of assumptions in my question - namely that we can move water to the hole in a steady consistent fashion and that we can build a steam turbine at the hole or close enough to the production of steam to be useful.

I don't know if the water would eventually cool down the heat source. I just think about underwater magma and how that seems to continuously flow.

submitted by /u/flippingtimmy
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Is there any actual physical motion involved with the Metric Expansion of the Universe and the Big Bang?

Posted: 29 Jun 2017 09:56 AM PDT

If I understand the theory correctly, all distant galaxies are sitting still in space essentially motionless with respect to the Milky Way and this has been the case ever since the moment of the Big Bang. Distances are increasing between distant objects but nothing is in motion. That is why we have concepts like cosmological red shift (caused by the universe expanding and NOT by motion) and the Co-moving coordinate system which depicts the universe as essentially static.

Am I missing something?

I know that there is never zero motion. However, on the scale of the universe the motions of stars in a galaxy or galaxies in a cluster are like the motions of atoms within a diamond (or not?) The atoms are moving but the diamond is static and you could use atoms in a massive diamond to map the galaxies in the universe with an equal amount of relative motion.

Is there some motion involved with the Big Bang and the expansion of the universe that I don't know about? Is there something in the universe actually moving due to these effects in such a way as to have relative velocity to something else in the universe?

I know that the Big Bang and the Expansion of the Universe made room for the 4 forces to work in but motions like the orbits of stars in galaxies are caused by gravity not the expansion of the universe (right?)

The Big Bang and the Expansion of the Universe seem to be described using action words in all the videos I can find. Nowhere does it describe a silent, frozen, universe. However, cosmological red shift and the co-moving coordinate system seem like concepts invented to describe a static universe experiencing a metric expansion of space. Please help me understand what is going on.

submitted by /u/timpatry
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Why do galaxies form into a disc shape rather than a perfect sphere such as a star or planet?

Posted: 29 Jun 2017 04:44 PM PDT

What is going on in your brain when you're unconscious?

Posted: 29 Jun 2017 08:17 PM PDT

Also, are there different levels of unconsciousness?

submitted by /u/bonnefemmefatale
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Why does vision improve when one is squinting?

Posted: 29 Jun 2017 08:07 AM PDT

Why do we need sleep?

Posted: 29 Jun 2017 07:06 PM PDT

I asked a friend and he said it was probably because our body's muscles get tired and need to rest, but I didn't think this was right as we can just eat food to give us energy.

submitted by /u/majestic_maniac
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If space technology has evolved so much in recent times, why aren't more astronauts going to the moon?

Posted: 30 Jun 2017 12:45 AM PDT

Do people with high pain tolerances just handle the pain better or not feel it as much?

Posted: 29 Jun 2017 06:05 AM PDT