Concepts Of Physics MCQ Edition [Volume 2]PhysicsLaws of Thermodynamics
Determine the heat absorbed by a system undergoing the cyclic process depicted in the figure.
Options
- A10.0 J
- B3.14 J
- C31.4 J
- D314 J
Correct answer
C. 31.4 J
Step-by-step solution
For a cyclic process, the change in internal energy is zero ( U = 0 ). According to the first law of thermodynamics, the heat absorbed is equal to the work done: Q = W The magnitude of work done in a cyclic process is given by the area enclosed by the cycle on the indicator diagram. From the given V-p graph, the semi-axes of the closed curve are: r_p = 300 - 100 2 = 100 kPa = 10^5 Pa r_V = 300 - 100 2 = 100 cc = 100 10⁻⁶ m ^3 = 10⁻⁴ m ^3 The area of the cycle is: Area = r_p r_V Area = (10^5 Pa ) (10⁻⁴ m ^3) Area =