The relation between internal energy $U$, pressure $P$ and volume $V$ of gas in an adiabatic process is $\mathit{\text{U}}=a+\mathit{\text{bPV}}$, where $a$ and $b$ are constants. What is the effective value of adiabatic constant $\gamma$?

• A

  $\frac{\mathit{\text{a}}}{\mathit{\text{b}}}$
• Correct answer
  B

  $\frac{\mathit{\text{b}}+1}{\mathit{\text{b}}}$
• C

  $\frac{a+1}{a}$
• D

  $\frac{\mathit{\text{b}}}{\mathit{\text{a}}}$

Hence, the correct answer is option: 'B'.