In a polytropic thermodynamic process, temperature is not constant, despite the equation pv^n=c suggesting a relationship between pressure and volume at different states. This equation is derived from the analysis of gas experiments, but it does not imply isothermal or adiabatic conditions. Instead, it applies to quasistatic processes involving simple compressible gas systems, where heat transfer is not negligible. The equation allows for various values of n, with specific cases like n=1 for isothermal and n=γ for adiabatic processes. The term "polytropic" was introduced to describe these processes that adhere to the p-v relationship under controlled temperature conditions. The derivation of the equation itself remains unclear, prompting further inquiry into its origins.
