BY 54. Assertion (A): For an adiabatic expansion process, work done by the system is equal to the change in internal energy. Reason (R): In adiabatic process, there is no heat exchange between system and surrounding. (1) Both Assertion & Reason are true and the reason is the correct explanation of the assertion (2) Both Assertion & Reason are true but the reason is not the correct explanation of the assertion (3) Assertion is true statement but Reason is false (4) Both Assertion and Reason are false statements​