Assuming the expression for the pressure exerted by the gas, it can be shown that pressure is

Assuming the expression for the pressure exerted by the gas, it can be shown that pressure is
  1. $\left(\frac{3}{4}\right)^{\text {th }}$ of kinetic energy per unit volume of a gas.
  2. $\left(\frac{2}{3}\right)^{\text {rd }}$ of kinetic energy per unit volume of a gas.
  3. $\left(\frac{1}{3}\right)^{\text {rd }}$ of kinetic energy per unit volume of a gas.
  4. $\left(\frac{3}{2}\right)^{\text {rd }}$ of kinetic energy per unit volume of a gas.

Solution

Pressure exerted by the gas on wall of container is given by, $\begin{aligned} \quad P & =\frac{1}{3} \rho v^2 \\ \therefore \quad P & =\frac{1}{3}\left(\frac{M}{V}\right) v^2 \end{aligned}$ $(\mathrm{v}=$ r.m.s. speed $)$ Dividing and multiplying equation by 2 , $\begin{aligned} & P=\frac{2}{3} \quad \frac{1}{2}\left(\frac{M}{V}\right) v^2 \\ & \left(V=\frac{2}{3}\left(\frac{\text { Volume of the gas })}{V}\right)\right. \\ & \therefore \quad \ldots\left(\because \text { K.E. }=\frac{1}{2} M v^2\right) \end{aligned}$ ~

Asked in: MHT CET 2024 (16 May Shift 1)

Practice more Kinetic Theory of Gases and Radiation questions on Aicharya