Question

A certain mass of an ideal gas undergoes a reversible isothermal compression. Its molecules, compared with the initial state, will then have the same
(i) root mean square velocity
(ii) mean momentum
(iii) mean kinetic energy

• A. (i), (ii), (iii)
• B. (i), (ii)
• C. (ii), (iii)
• D. (i)

Answer 1

The correct option is A (i), (ii), (iii)

Given process is isothermal i.e, $T$ is constant so, root mean velocity $=\sqrt{\frac{3KT}{M}}$ is constant mean momentum is always zero mean kinetic energy is $\frac{1}{2}M{V}_{av}^2$ where

$\Rightarrow V_{av}=\sqrt{\frac{8KT}{\pi M}}$ is constant at constant $T.$

Hence, $\left(i\right),\left(ii\right),\left(iii\right)$ are correct answer.