NTA Abhyas JEE Main2020PhysicsThermodynamicsPractice
A cylindrical adiabatic container of total volume 2 V 0 is divided into two equal parts by a conducting piston which is free to move as shown in the figure. Each part contains identical gas at pressure P 0 . Initially the temperatures of the left and right parts are 4 T 0 and T 0 respectively. An external force is applied on the piston of area A to keep the piston at rest. The value of external force required when th
Options
- A8 5 P 0 A
- B2 5 P 0 A
- C5 6 P 0 A
- D6 5 P 0 A
Correct answer
D. 6 5 P 0 A
Step-by-step solution
If final temp is T P 0 V 0 4 RT 0 C v 4 T 0 - T = P 0 V 0 RT 0 C v T - T 0 4 T 0 - T 4 = T - T 0 4 T 0 - T = 4 T - 4 T 0 8 T 0 = 5 T T = 8 T 0 5 Final pressure In left P f = T f T 0 P i = 8 5 T 0 4 T 0 P 0 = 2 5 P 0 In right P f = 8 5 T 0 T 0 P 0 = 8 5 P 0 Force = 8 P 0 5 - 2 P 0 5 A = 6 P 0 A 5