The relation \( PV^{\gamma} = \text{constant} \) is the equation for an adiabatic process, where \( \gamma = \frac{C_p}{C_v} \) is the heat capacity ratio.
- Adiabatic process refers to a process where no heat is exchanged with the surroundings, i.e., \( Q = 0 \). In this case, the process follows the equation \( PV^{\gamma} = \text{constant} \), where \( \gamma = \frac{C_p}{C_v} \).
- Isothermal process is characterized by a constant temperature, and the equation for an isothermal process is \( PV = \text{constant} \), not \( PV^{\gamma} = \text{constant} \).
- Isobaric process refers to a process occurring at constant pressure, and its equation is \( P = \text{constant} \), not \( PV^{\gamma} = \text{constant} \).
- Isochoric process occurs at constant volume, and the equation is \( V = \text{constant} \), not \( PV^{\gamma} = \text{constant} \).
Thus, \( PV^{\gamma} = \text{constant} \) corresponds to an adiabatic process.