Q 11-11-122JEE MainJEE Main 2021 (18 Mar, Shift 2)Easy
An ideal gas in a cylinder is separated by a piston in such a way that the entropy of one part is $S_1$ and that of the other part is $S_2$. Given that $S_1 > S_2$. If the piston is removed then the total entropy of the system will be:
Answer: (D) $S_1 + S_2$
Entropy is an extensive quantity, so the entropy of the whole system is the sum of the entropies of its parts: $S_1 + S_2$. (The intended answer ignores any extra entropy of mixing.)
Solution by Sreeraj P, M.Sc Physics