The internal energy change in a system that has absorbed $2 \, kcal$ of heat and done $500 \, J$ of work is ...... $J$.

An electric heater supplies heat to a system at a rate of $100\;W.$ If the system performs work at a rate of $75\;J/s,$ at what rate (in $J/s$) is the internal energy increasing?

Which of the following statements is incorrect regarding the first law of thermodynamics?

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

The $P-V$ diagram of a system undergoing a thermodynamic transformation is shown in the figure. The work done on the system in going from $A \to B \to C$ is $50 \, J$ and $20 \, cal$ of heat is given to the system. The change in internal energy between $A$ and $C$ is ...... $J$.

$200\,g$ of water is heated from $40\,^{\circ}C$ to $60\,^{\circ}C$. Ignoring the slight expansion of water,the change in its internal energy is close to ...... $kJ$ (Given specific heat of water $= 4184\,J/kg\cdot K$)