Question

Pressure exerted by a perfect gas is equal to

• A. mean kinetic energy of translation per unit volume
• B. half of mean kinetic energy of translation per unit volume
• C. two third of mean kinetic energy of translation per unit volume
• D. one third of mean kinetic energy of translation per unit volume

Answer 1

The correct option is C two third of mean kinetic energy of translation per unit volume

$P=\frac{\frac{1}{3}\left(mN{v}_{rms}^2\right)}{V}=\frac{\frac{2}{3}\left(\frac{1}{2}mN{v}_{rms}^2\right)}{V}$
where, $m$ is mass of molecule of gas, $N$ is number of molecules in gas and $v_{rms}$ is root mean square velocity of the molecule.

Pressure exerted by a perfect gas is equal to two third of mean kinetic energy of translation per unit volume