In an adiabatic expansion the product of pressure and volume.

Two rigid boxes containing different ideal gases are placed on a table. Box $A$ contains one mole of nitrogen at temperature $T_0$, while box $B$ contains one mole of helium at temperature $\left( {\frac{7}{3}} \right){T_0}$. The boxes are then put into thermal contact with each other, and heat flows between them until the gases reach a common final temperature (ignore the heat capacity of boxes). Then, the final temperature of the gases, $T_f$ in terms of $T_0$ is

In the $P-V$ diagram shown, the gas does $5\,J$ of work in isothermal process $ab$ and $4\,J$ in adiabatic process $bc$ .   .... $J$ will be the change in internal energy of the gas in straight path $c$ to $a$ ?

A Carnot's engine working between $300\, K$ and $600\, K$ has a work output of $800\, J$ per cycle. How much heat energy is supplied to the engine from  the source in each cycle ?  .... $J$

Six moles of an ideal gas performs a cycle shown in figure. If the temperatures are $T_A = 600\, K,$ $T_B = 800\,K,$ $T_C = 2200\,K$ and $T_D = 1200\,K,$ then the work done per cycle is approximately ...... $kJ$

A carnot engine, having an efficiency of $\eta  = 1/10$ as heat engine, is used as a refrigetator. If the work done on the system is $10\,J$ , the amount of energy absorbed from the reservoir at lower temperature is .......... $\mathrm{J}$