MHTCET 19 Apr 2026 Shift 2 Paper

Concept:From the kinetic theory of gases, pressure is directly related to the average kinetic energy of gas molecules per unit volume.Explanation:The expression for pressure exerted by a gas is given by:$$P = \frac{1}{3}\rho \overline{v^2}$$Here, $\rho$ is the gas density and $\overline{v^2}$ is the mean square speed of the molecules.The kinetic energy per unit volume of the gas is:$$u = \frac{1}{2}\rho \overline{v^2}$$Now, compare the two expressions by writing $P$ in terms of $u$:$$P = \frac{2}{3}\left(\frac{1}{2}\rho \overline{v^2}\right) = \frac{2}{3}u$$Thus, pressure equals $\frac{2}{3}$ of the kinetic energy per unit volume of the gas.Answer:Pressure is $\frac{2}{3}$ of kinetic energy per unit volume of a gas, so the correct option is A.