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The same way any substance can have transnational energy. It arises because the energy of motion is proportional to the square of the velocity so even if the average is zero, the average of the square is not. If the mean velocity of the particles is $\bar v$ then the instantaneous transnational energy would be: $$\frac12 m\sum_i (v_i-\bar v)^2$$ ...

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there are 3 degrees of freedom in translational movement, 1 degree in vibration and the last is in rotation Actually there are 3 translational, 2 rotational, and 1 vibrational degree of freedom for a two-atomic molecule. The vibrational one is not shown in this picture, although it's easy to see what it is (atoms oscillating along the molecular bond ...

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The process is known as galling, or more popularly adhesive transfer or adhesive wear. It isn't unique to titanium-glass but is seen in many systems. Exactly why it happens in the titanium glass system I don't know, though there are some obvious general points. Clean glass is an exceedingly high energy surface with a very high friction. When we meet glass ...

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The "Ideal Gas Law" (IGL) (pV = nRT) is an "equation of state" and any such equation is a relation between the macroscopical "state variables" of a matterial system in a given phase. Therefore, the form of a state equation depends on the system's phase. The basic assumption of the IGL is that the molecules do not interact by any other means besides point ...

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The ideal gas law applies in systems made of large number of particles (atoms or molecules) that are completely independent from each other as in a dilute gas. In that situation, the particles are able to move in all space directions without interfering with the others. That's an ideal situation, hence the name ideal gas. The law $$PV=nRT$$ is an immediate ...

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This formula is strictly applicable for gases. So what happens to this formula is it is no longer valid. Provided the gas density is low, this law holds for any single gas or for any mixture of different gases. However it is interesting that for osmotic pressure of a liquid we have a similar formula $$\pi=CRT$$ where $\pi$ is osmotic pressure and $C$ is ...

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You conclude: "My intuition is that with 100's of M's of years to even out and settle down, it would be surpassingly smooth and quiescent." According to the history of the universe here , the dark ages happen after the decoupling of photons and the Cosmic Microwave Background radiation which happened around 380.000 years after the Big Bang. CMB is ...

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I've located a paper that goes into great (excruciating?) detail on the 21cm power spectrum (of baryons) in the dark ages. I won't pretend to have the expertise to understand the whole thing, but I'll try to bring out a couple of relevant points here. Note that this is all theoretical work in the framework of the standard cosmological model since actual ...

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