Thermodynamics, Statistical Physics, and Quantum Mechanics

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The temperature may befound from theequation foradiabats and the

ideal gas law:

Rewritinggives

Substituting into (S.4.22.4) gives

The maximumvelocity will bereachedwhen flow into vacuum.

b) For one mole of an ideal gas

and, by definition,

From(S.4.22.9) and (S.4.22.10), we mayexpress and through R
and

Then (S.4.22.8) becomes

For molecularhydrogen we have

THERMODYNAMICS AND STATISTICAL PHYSICS