Umakant Kondapure, Collin Fernandes, Nipun Bhatia, Vikram Bathula and, Ketki Deshpande Solutions for Chapter: Kinetic Theory of Gases and Radiations, Exercise 2: Critical Thinking

In an isothermal reversible expansion, if the volume of $96 \mathrm{g}$ of oxygen at $27^{\circ} \mathrm{C}$ is increased from $70 \mathrm{L}$ to $140 \mathrm{L}$, then the work done by the gas will be

Efficiency of a Carnot engine is $50 \%$ when temperature of outlet is $500 \mathrm{K}$. In order to increase efficiency up to $60 \%$ keeping temperature of intake the same, what is temperature of outlet?

The volume of air increases by $5 \%$ in its adiabatic expansion. The percentage decrease in its pressure will be

In the following indicator diagram, the net amount of work done will be

The temperature v/s time graph is shown .Out of  $\mathrm{P}, \mathrm{Q}$ or $\mathrm{R}$ Which of the substances has the lowest specific heat?

A gas at absolute temperature of $300 \mathrm{K}$ has pressure of $4\times {10}^{-10} \mathrm{N} {\mathrm{m}}^{-2}$. Boltzmann's constant $k_{\mathrm{B}}=1.38\times {10}^{-23} \mathrm{J} {\mathrm{K}}^{-1}.$ The number of molecules per ${\mathrm{cm}}^3$ is of the order of,

Assertion: If a gas is heated isothermally, then no part of the heat supplied is used to increase the internal energy.

Reason: Change in internal energy equals work done on the system.

A Carnot engine whose efficiency is $40\%$ takes in heat from a source maintained at a temperature of $500 \mathrm{K}$. It is desired to have an engine of efficiency $60\%$. Then the intake temperature for the same exhaust (sink) temperature must be,