Question

Figure shows an isochore, an isotherm, an adiabatic and two isobars of two gases on a work done versus heat supplied curve. The initial states of both gases are the same and the scales for the two axes are same. Which of the following statements is incorrect?

• A. Straight line 1 corresponds to an isochoric process.
• B. Straight line 2 corresponds to an isobaric process for diatomic gas.
• C. Straight line 4 corresponds to an isothermal process.
• D. Straight line 5 corresponds to an isothermal process.

Answer 1

Answer: (D)

Straight line 5 corresponds to an isothermal process.

In Isochoric process, $W=0$

In isobaric process, $W=nRdTandQ=\frac{n\gamma R}{\gamma -1}$

so for diatomic gas, $\frac{W}{Q}=2/7$

In isothermal process, $W=Q$

So, option D is incorrect.