In a certain thermodynamical process, the pressure of a gas depends on its volume as $kV ^{3}$. The work done when the temperature changes from $100^{\circ} C$ to $300^{\circ} C$ will be ………. $nR$, where $n$ denotes number of moles of a gas.

Consider a process shown in the figure. During this process the work done by the system

The above $P-V$ diagram represents the thermodynamic cycle of an engine, operating with an ideal monatomic gas. The amount of heat, extracted from the source in a single cycle is

A thermodynamic system is taken from an original state $A$ to an intermediate state $B$ by a linear process as shown in the figure. It's volume is then reduced to the original value from $B$ to $C$ by an isobaric process. The total work done by the gas from $A$ to $B$ and $B$ to $C$ would be :

$1c{m^3}$ of water at its boiling point absorbs $540$ calories of heat to become steam with a volume of $1671c{m^3}$.If the atmospheric pressure = $1.013 \times {10^5}N/{m^2}$ and the mechanical equivalent of heat = $4.19J/calorie$, the energy spent in this process in overcoming intermolecular forces is ….. $cal$