For a gas, γ = 9/7. What is the number of degrees of freedom of the molecules of this gas ?
Physics · Thermodynamics
JEE Advanced

Question

For a gas, γ = 9/7. What is the number of degrees of freedom of the molecules of this gas ?

G1 Physics · Accepted Answer

Use PV=nRT, U=(f/2)nRT, γ=1+2/f and vᵣₘₛ=√(3RT/M). At the same temperature, average translational kinetic energy depends only on T. Substituting the given values gives 7.