CONCEPT:For isentropic or reversible adiabatic process the P-V-T RELATION is given by\(\frac{{{T_2}}}{{{T_1}}} = {\left( {\frac{{{V_1}}}{{{V_2}}}} \right)^{γ - 1}} = {\left( {\frac{{{P_2}}}{{{P_1}}}} \right)^{\frac{{γ - 1}}{γ }}}\)or P = K Tγ /γ - 1The given relation for the isentropic process in the question ISP = K T5/2Comparing the above relationship with the standard relation of the isentropic process we will get,\(\frac{\GAMMA}{\gamma\;-\;1}=\frac{5}{2}\)2γ = 5γ - 5, 3γ = 5 or γ = 5/3