Three processes form a thermodynamic cycle as shown on P-V diagram for an ideal gas. Process 1 → 2 takes place at constant temperature (300K). Process 2 → 3 takes place at constant volume. During this process 40J of heat leaves the system. Process 3 → 1 is adiabatic and temperature T₃ is 275K. Work done by the gas during the process 3 →1 is :-

Question

G1 Physics · Accepted Answer

Use the first law Q=ΔU+W (W by the gas), ΔU=nCᵥΔT for an ideal gas, and the appropriate process relation. For Carnot devices, let T₁ be the cold-reservoir temperature and T₂ be the hot-reservoir temperature; η=1-T₁/T₂ and COP=T₁/(T₂-T₁). Evaluating the given data/statements gives - 40J. Therefore the correct answer is A.