Adiabatic Process State Equation Pv Constant — the NEET Physics formula with its derivation, variables, validity constraints and worked solver.
Adiabatic Process State Equation (PV γ = constant) Applies to ideal gases undergoing a reversible adiabatic (isentropic) process. Start with the First Law of Thermodynamics: dU = dQ - dW. Apply adiabatic condition dQ = 0, so dU = -dW. Substitute dU = n Cv dT and dW = P dV. Use Ideal Gas Law PV = nRT to differentiate and substitute for dT. Separate variables P and V, integrate using gamma = Cp/Cv. Ideal Gas Law holds Process is adiabatic (Q=0) Process is reversible (quasi-static) Heat capacities are constant over the temperature range Confusing adiabatic processes with isothermal processes (where PV = constant). Using gauge pressure instead of absolute pressure. Assuming gamma is always 1.4 regardless of the gas type.