KVPY2018PhysicsThermodynamics
An ideal gas is made to undergo the cyclic process shown in the figure below. Let Δ W depict the work done, Δ U be the change in internal energy of the gas and Q be the heat added to the gas. Sign of each of these three quantities for the whole cycle will be ( 0 refers to no change)
Options
- A- , 0 , -
- B+ , 0 , +
- C0 , 0 , 0
- D+ , + , +
Correct answer
A. - , 0 , -
Step-by-step solution
Given cyclic process is Area under compression process C A is more than area under expansion process A B . So, net work done is negative. i.e. Δ W 0 Also, in a cyclic process, change in internal energy is zero. i.e. Δ U = 0 Now, by using first law of thermodynamics, we have Δ Q = 0 + Δ W we see that, Δ Q 0