Thermodynamics — Hard JEE physics MCQ
List I describes thermodynamic processes in four different systems. List II gives the magnitudes (either exactly or as a close approximation) of possible changes in the internal energy of the system due to the process.
List-I
(I) $10^{-3} \mathrm{~kg}$ of water at $100^{\circ} \mathrm{C}$ is converted to steam at the same temperature, at a pressure of $10^5 \mathrm{~Pa}$. The volume of the system changes from $10^{-6} \mathrm{~m}^3$ to $10^{-3} \mathrm{~m}^3$ in the process. Latent heat of water $=2250 \mathrm{~kJ} / \mathrm{kg}$.
(II) 0.2 moles of a rigid diatomic ideal gas with volume $V$ at temperature $500 \mathrm{~K}$ undergoes an isobaric expansion to volume $3 \mathrm{~V}$. Assume $R=8.0 \mathrm{~J} \mathrm{~mol}^{-1} \mathrm{~K}^{-1}$.
(III) One mole of a monatomic ideal gas is compressed adiabatically from volume $V=\frac{1}{3} m^3$ and pressure $2 \mathrm{kPa}$ to volume $\frac{V}{8}$.
(IV) Three moles of a diatomic ideal gas whose molecules can vibrate, is given $9 \mathrm{~kJ}$ of heat and undergoes isobaric expansion.
List-II
(P) $2 \mathrm{~kJ}$
(Q) $7 \mathrm{~kJ}$
(R) $4 \mathrm{~kJ}$
(S) $5 \mathrm{~kJ}$
(T) $3 \mathrm{~kJ}$
Which one of the following options is correct?\
- A. $\mathrm{I} \rightarrow \mathrm{T}$, II $\rightarrow$ R, III $\rightarrow \mathrm{S}$, IV $\rightarrow$ Q,
- B. I $\rightarrow \mathrm{S}$, II $\rightarrow$ P, III $\rightarrow \mathrm{T}$, IV $\rightarrow$ P,
- C. I $\rightarrow$ P, II $\rightarrow$ R, III $\rightarrow$ T, IV $\rightarrow$ Q.
- D. I $\rightarrow$ Q, II $\rightarrow$ R, III $\rightarrow \mathrm{S}$, IV $\rightarrow \mathrm{T}$,
Solution
The correct option is **C**.