NTA Abhyas JEE Main2020PhysicsThermodynamicsPractice
One mole of a monoatomic ideal gas undergoes the process A ⟶ B , as in the given P - V diagram. The specific heat for this process is
Options
- A3 R 2
- B15 R 7
- C30 R 7
- D20 R 7
Correct answer
B. 15 R 7
Step-by-step solution
Δ Q = Δ U + W (From 1 s t law) Here, Δ U = n C V Δ T Temperature at A , T A = 2 P 0 V 0 R At B , T B = 16 P 0 V 0 R So, Δ U = 3 2 R 14 P 0 V 0 R = 21 P 0 V 0 W = 2 P 0 3 V 0 + 1 2 3 V 0 2 P 0 [Area under P - V diagram] = 9 P 0 V 0 So, Δ Q = 21 P 0 V 0 + 9 P 0 V 0 = 30 P 0 V 0 Δ Q = n C Δ T C = Δ Q n Δ T = 30 P 0 V 0 14 P 0 V 0 R = 15 7 R