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Question
Refer to figure. Let ∆U1 and ∆U2 be the changes in internal energy of the system in the process A and B. Then _____________ .
Options
∆U1 > ∆U2
∆U1 = ∆U2
∆U1 < ∆U2
∆U1 ≠ ∆U2
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Solution
∆U1 = ∆U2
The internal energy of the system is a state function, i.e. it only depends on the initial and final point of the process and doesn't depend on the path followed. Both processes A and B have common initial and final points. Therefore, change in internal energy in process A is equal to the change in internal energy in process B. Thus,
∆U1 = ∆U2 = 0
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