A diatomic gas (γ = 1.4) does 100 J of work when it is expanded isobarically. Then the heat given to the ga s __________ J.

Question

G1 Physics · Accepted Answer

For an isobaric process of an ideal gas, W = nRΔT. Given, W = 100 J. Also, γ = Cₚ/Cᵥ = 1.4. Using Cₚ - Cᵥ = R, we have Cₚ/R = γ/(γ - 1). Therefore, Cₚ/R = 1.4/0.4 = 3.5 = 7/2. Heat supplied at constant pressure is Q = nCₚΔT = (Cₚ/R)nRΔT. Thus, Q = (7/2)(100) = 350 J. Therefore the answer is 350.