A certain volume of a gas at 300 K expands adiabatically until its volume is doubled. The resultant fall in temperature of the gas is nearly (The ratio of the specific heats of the gas $=1.5$ )

The efficiency of a Carnot's engine is $25 \%$. When the temperature of sink is 300 K . The increase in the temperature of source required for the efficiency to become $50 \%$ is

When 100 J of heat is supplied to a gas, the increase in the internal energy of the gas is 60 J . Then the gas is /can

An ideal gas is kept in a cylinder of volume $3 \mathrm{~m}^3$ at a pressure of $3 \times 10^5 \mathrm{~Pa}$. The energy of the gas is