Which of the following statement is correct regarding \(p-V\) graph? 1. Slope of \(p-V\) graph in an isothermal process is \(-\frac{p}{V}\). 2. Slope of \(p-V\) graph in an adiabatic process is \(-\frac{p}{V}\). 3. Slope of \(p-V\) graph in an isochoric process is \(-\frac{\gamma p}{V}\). 4. Slope of \(p-V\) graph in an isobaric process is zero.

(i) and (iv) options are correct. (i) Slope of \(p-V\) graph in an isothermal process is \(-\frac{p}{V}\) this is correct.
For isothermal process, slope of \(p-V^{\prime}\) curve \(\frac{d p}{d V}=-\frac{p}{V}\) (ii) Slope of \(p-V\) group in an adiabatic process is \(-\frac{p}{V}\), which is wrong.
Because slope of \(p-V\) graph in an adiabatic process is \(-\frac{\gamma p}{V}\). (iii) Slope of \(p\) - \(V\) graph in an isochoric process is \(-\frac{\gamma p}{V}\) this option is wrong. Because slope of \(p-V\) graph for isochoric process is \(\frac{d p}{-\frac{d V}{V}}-\frac{d V}{V}=\frac{d p}{0}=\infty\)
(d) Slope of \(p-V\) graph in an isobaric process is zero. This option is correct.
\(p-V\) curve is a straight line parallel to volume axis, slope of \(p\) - \(V\) curve for an isobaric process \(\frac{d p}{d V}=0.\)