When heat $\mathrm{Q}$ is supplied to a diatomic gas of rigid molecules, at constant volume its temperature increases by $∆\mathrm{T}$ . The heat required to produce the same change in temperature, at a constant pressure is:

• A

  $\frac{3}{2}\mathrm{Q}$
• Correct answer
  B

  $\frac{7}{5}\mathrm{Q}$
• C

  $\frac{5}{3}\mathrm{Q}$
• D

  $\frac{2}{3}\mathrm{Q}$

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