how will you account for five degree of freedom in a di - atomic molecule. using idea of equipartition of energy, find value of gamma(Y) for the same.

For a diatomic rigid molecule, p = 5 

from equipartition of energy:avg energy per molecule per degree of freedom=1/2 kT

total internal energy of 1 gm mole of di atomic gas=U=5/2 kTxN=5/2 RT....(1)

Cv=dU/dT =5/2 R.............(2)

Cp-Cv=R

Cp=7/2 R

so Y=7/5=1.4