railway RRB JE (CBT I + CBT II) Mock Test 2024 Thermodynamics Second Law of Thermodynamics and Entropy Entropy and Irreversibility
An ideal gas of mass m and temperature T1 undergoes a reversible isothermal process from an initial pressure P1 to a final pressure P2. The heat loss during the process is Q. The entropy change ΔS of the gas is
1
\(mR\ln \left( {\frac{{{P_2}}}{{{P_1}}}} \right)\)
2
\(mR\ln \left( {\frac{{{P_1}}}{{{P_2}}}} \right)\)
3
\(mR\ln \left( {\frac{{{P_2}}}{{{P_1}}}} \right) - \frac{Q}{{{T_1}}}\)
4
Zero