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4.2k

E.g. my abdominal muscles will burn while doing crunches, while my arms will just stop moving while doing chin-ups.

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I was doing some reading on refractive index of gasses and how that leads to ionospheric propagation of radio waves, but none of the resources I found explain the correlation between increased upper atmosphere ionization levels and increased angle of refraction.

I know that the precise refractive index of a gas is highly dependent on frequency, but I haven't been able to find even a vague outline of whether the refractive index of a gas goes up or down with increasing ionization, and it seems that either direction could explain the increased angle of refraction at a given frequency, depending on where in the ionosphere the "virtual reflector" is located. What papers I've found are all regarding self focusing and scattering of lasers in plasmas and such, and while the information I want might be there, it's so abstract that I can't find it.

The most logical explanation seems to be that ionized gas has a higher refractive index, which creates a tighter gradient between the index of the atmosphere (which is >1) and space (which is ~1), which leads to total internal refraction at a higher incident angle.

The other way of looking at it seems almost as logical though; that only the upper most layers of the atmosphere become ionized, dropping the refractive index of that layer closer to the ~1 of space, which still results in a tighter gradient between space and atmosphere, but at a lower altitude.

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Can you build a radio camera that would let you to see router antenna signal as "light source"?

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So recently there have been planet wide wind storms on Mars. I looked up some information about Mars' atmosphere and saw that it has 0.6% of the pressure Earth has at sea level. If this is true how is there enough of a pressure difference in the atmosphere on Mars to produce winds strong enough and for a great enough periods of time that a planet wide storm is born that literally shapes the way the surface looks.

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I live in a coastal town and it always seems that a high tide is a lot higher when it occurs in the evening/night as opposed to in the day. Is this just coincidence or is there something else causing this?

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By the uncertainty principle and limitations on our computational abilities, we humans can never model the universe's evolution. Is that what non-determinism refers to? (i.e. specifically with respect to humanity's point of view)

Suppose a higher, external being was able to observe the exact state of the universe at any point in time. Can it be said that it sees the universe as deterministic?

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I see people sometimes call the computers that D-Wave makes controversial and not a "real" quantum computer. So what makes one a "real" quantum computer? Is it just people throwing shade at D-Wave, or are their computers more like pseudo quantum computers?

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Hi, I hope I don't sound stupid asking this question. Is it possible to harness energy through sound waves? They're vibrations which is a form of energy, right?

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Was just thinking about how data is stored, and how it might be more efficient. Any work or reading someone could direct me to understanding that more would be appreciated.

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I am assuming that the object would have no ability to rebound and would simply begin to plasticly deform.

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Studying about the nature of supercapacitors lead me to consider this idea:

At the discharged state of a supercapacitor, with ions spread uniformly within the electrolyte, and not connected to a power supply, only forming a circuit with a resistor. Wouldn't it be possible to separate the charges using an exterior magnetic field?

Accelerating a 2000F capacitor, in a strong magnetic field(1T+) would give rise to a Lorentz force(F = q(E + v) x B) that would separate the positive/negative ions wouldn't it?

I also think, that if the capacitor was intially charged then connected to a circuit and moved rapidly in that strong magnetic field, the discharge would be affected due to the Lorentz force acting on the (+&-)ions?

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