Question

Assertion In adiabatic process, work is independent of the path.
Reason In adiabatic process, work done is equal to negative of change in internal energy.

• A. Both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
• B. Both Assertion and Reason are correct but Reason is not the correct explanation of Assertion.
• C. Assertion is correct but Reason is incorrect.
• D. Assertion is incorrect but Reason is correct.

Answer 1

Answer: (A)

In adiabatic process, heat transfer to the thermodynamic system is zero,
i.e. $\Delta Q=0$.
Hence, by first law of thermodynamics,
$Q=0=\Delta U+\Delta W$
$\therefore W=-\Delta U$
So, work done is equal to negative of change in internal energy.
Since, the internal energy is a function of thermodynamic state of the system.
It does not depend on the path, therefore work done is also independent of path in adiabatic process.
Therefore, Assertion and Reason are correct and Reason is the correct explanation of Assertion.