Q 11-12-019NEETJEE MainMedium
A diatomic gas is at a high enough temperature that its vibrational mode is also excited. Its ratio of specific heats $\gamma$ is
Answer: (A) $\dfrac{9}{7}$
Degrees of freedom: $3$ translational, $2$ rotational, and $2$ for vibration (kinetic and potential), so $f = 7$.
$\gamma = 1 + \dfrac{2}{f} = 1 + \dfrac{2}{7} = \dfrac{9}{7}$.
Solution by Sreeraj P, M.Sc Physics