Embibe Experts Solutions for Chapter: Thermodynamics, Exercise 1: KEAM 2018

The values of ${\mathrm{C}}_{\mathrm{p}}$ and ${\mathrm{C}}_{\mathrm{v}}$ for a diatomic gas are respectively $(\mathrm{R}=\mathrm{g} \mathrm{a} \mathrm{s}$ constant)

If a monoatomic gas is compressed adiabatically to $(1/27)$ th of its initial volume, then its pressure becomes

In a thermodynamic system, $Q$ represents the energy transferred to or from a system by heat and $W$ represents the energy transferred to or from a system by work

(I) $Q>0$ and $W=0$

(II) $Q<0$ and $W=0$

(III) $W>0$ and $Q=0$

(IV) $W<0$ and $Q=0$

Which of the above will lead to an increase in the internal energy of the system?

Five moles of an ideal monoatomic gas with an initial temperature of $150 °\mathrm{C}$ expand and in the process absorb $1500 \mathrm{J}$ of heat and does $2500 \mathrm{J}$ of work. The final temperature of the gas in $°\mathrm{C}$ is (ideal gas constant, $R=8.314\mathrm{ }\mathrm{J} {\mathrm{K}}^{-1} {\mathrm{mol}}^{-1}$ ). 

A Carnot engine is operating between a hot body and cold body maintained at temperature $T_1$ and $T_2$ respectively. Consider the following three cases

Case I : The temperature of the hot body is changed to $T_1+\Delta T$ and cold body is at $T_2$

Case II : The temperature of the hot body is at $T_1$ and cold body is changed to $T_2+\Delta T$

Case III : The temperature of the hot body is

A Carnot engine whose low-temperature reservoir is at $350 \mathrm{K}$ has an efficiency of $50\%$ . It is desired to increase this to $60\%$ . If the temperature of the low-temperature reservoir remains constant, then the temperature of the high-temperature reservoir must be increased by how many degrees?