I am in the first semester and I'm taking the course Molecular physics, which is an introduction to statistical physics and thermodynamics. It is not very advanced - it doesn't involve much of the higher mathematics.(adsbygoogle = window.adsbygoogle || []).push({});

But my problem is:

The probability density function of energy distribution is an exponential function which in general has the form:

[tex]w(\epsilon) = \frac{\exp(\beta\epsilon)}{\int\exp(\beta\epsilon)d\Gamma}[/tex]

that means that it is a decreasing function with the maximum in E = 0 - so the highest probability is that the molecules have an energy around zero.

If the gas is not in a force field, then the whole energy is just knietic energy. that means that the highest probability is that the velocity of molecules is around zero.

On the other hand the Maxwell speed distribution tells us that velocities around zero are not very probable.

What is wrong in this speculation?

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# Energy distribution and Maxwell speed distribution

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