The molar specific heats of an ideal gas at constant pressure and volume are denoted by Cₚ and Cᵥ respectively. If γ = Cₚ/Cᵥ and R is the universal gas constant, then Cᵥ is equal to:
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The molar specific heats of an ideal gas at constant pressure and volume are denoted by Cₚ and Cᵥ respectively. If γ = Cₚ/Cᵥ and R is the universal gas constant, then Cᵥ is equal to:

G1 Physics · Accepted Answer

Step 1: Mayer’s formula for an ideal gas is Cₚ − Cᵥ = R. Step 2: Since γ = Cₚ/Cᵥ, substitute Cₚ = γCᵥ. Step 3: γCᵥ − Cᵥ = R, or Cᵥ(γ − 1) = R. Step 4: Therefore Cᵥ = R/(γ − 1). Final answer: (B).