Question

Use the Debye approximation to find the following themodynamic functions of a solid as a function of the absolute temperature T

a) the fee energy F
b) the mean energy $\overline{E}$
c) the entropy S
Express your answers in terms of the Debye function D(y) =

and the Debye temperature $\Theta$_D = hw_max/k
e) Evaluate the function D(y) in the limit when y >> land y<<1. Use these results to express the thermodynamic functions F, $\overline{E}$ and S in the llimiting cases
when T << $\Theta$_{D and T>>}$\Theta$_D

e-1

Answer 1

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