Kinetic Theory Of Gases Question 150

Question: An adiabatic vessel contains $ n _{1}=3 $ moles of a diatomic gas. The moment of inertia of each molecule is $ I=2.56\times {{10}^{-46}},kgm^{2} $ and root mean angular velocity is $ {\omega _{0}}=5\times 10^{12},rad/s $ . The temperature of the gas in the vessel is

Options:

A) 250 K

B) 500 K

C) 1000 K

D) 1500 K

Show Answer

Answer:

Correct Answer: A

Solution:

[a]: Degree of freedom associated with rotational motion of diatomic gas molecules = 2 Average rotational energy per molecule

$ =l{{\omega }^{2}} _{rms}=2\times \frac{1}{2}kT=kT $

Hence initial temperature $ T _{1} $ of diatomic gas

$ =\frac{1}{2}l\omega _{0}^{2}=kT _{1} $

which give $ T _{1}=250,K $