Question

In adiabatic expansion

• A. $\Delta U = 0$
• B. $\Delta U =$negative
• C. $\Delta U =$positive
• D. $\Delta W =$zero

Answer 1

Answer: (B)

$\Delta U =$negative

Answer 2

In case of adiabatic expansion $\Delta W$ = positive and

$\Delta Q = 0$ from FLOT $\Delta Q = \Delta U + \Delta W$

⇒ $\Delta U = - \Delta W$ i.e., $\Delta U$will be negative.