As we know, Cv=f2R
and Cp=Cv+R=f2R+R
Therefore, γ=CvCp=1+f2
For monatomic gas, f=3 and hence γ1=35
For diatomic gas, f=5 and hence γ2=57
Required ratio, γ2γ1=2125
JEE Main 2023 — Physics Thermodynamics
Let γ1 be the ratio of molar specific heat at constant pressure and molar specific heat at constant volume of a monoatomic gas and γ2 be the similar ratio of diatomic gas. Considering the diatomic gas molecule as a rigid rotator, the ratio γ2γ1 is:
Held on 24 Jan 2023 · Verified 6 Jul 2026.
3527
2735
2125
2521
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