$A$ thermodynamic system absorbs $2 \, kcal$ of heat and performs $500 \, J$ of work. The change in its internal energy is ......... $J$.

When $2 \ kg$ of water is boiled at atmospheric pressure,it converts into steam. The volume increases from $2 \times 10^{-3} \ m^3$ to $3.34 \ m^3$. The work done by the system is ....... $kJ$.

The $P-V$ diagram of a system undergoing a thermodynamic transformation is shown in the figure. The work done by the system in going from $A \to B \to C$ is $30 \ J$ and $40 \ J$ of heat is given to the system. The change in internal energy between $A$ and $C$ is ....... $J$.

$1\,kg$ of water at $100^{\circ}C$ is converted into steam at $100^{\circ}C$ by boiling at atmospheric pressure. The volume of water changes from $1.00 \times 10^{-3}\,m^3$ as a liquid to $1.671\,m^3$ as steam. The change in internal energy of the system during the process will be $........kJ$ (Given latent heat of vaporisation $= 2257\,kJ/kg$. Atmospheric pressure $= 1 \times 10^5\,Pa$)

Calculate the change in internal energy when $1 \,g$ of water is converted into steam at atmospheric pressure $(1.013 \times 10^{5} \,Pa)$. Given the latent heat of vaporisation is $2256 \,J/g$, the volume of $1 \,g$ of water is $1 \,cm^{3}$, and the volume of $1 \,g$ of steam is $1671 \,cm^{3}$.

$A$ given quantity of gas is taken from $A$ to $C$ in two ways: $a$) directly from $A \rightarrow C$ along a straight line, and $b$) in two steps, from $A \rightarrow B$ and then from $B \rightarrow C$. The work done and heat absorbed along the direct path $A \rightarrow C$ are $200 \ J$ and $280 \ J$ respectively. If the work done along the path $A \rightarrow B \rightarrow C$ is $80 \ J$, find the heat absorbed along this path.