Practice question

**Adiabatic process** no heat exchange Q=0, first law ΔU = -W, for ideal gas P V^γ = constant, T V^{γ-1}= constant, P^{1-γ} T^{γ}= constant, γ = C_p/C_v = (f+2)/f, monatomic γ=5/3, diatomic γ=7/5. Work done W = (P₁V₁ - P₂V₂)/(γ-1), temperature changes due to work. Δ Q = m s Δ T . m = 0.2 , s = 236.1 , Δ T = 50 - 30 = 20 . Δ Q = 0.2 × 236.1 × 20 = 944.4 J ≈ 944 J . Using first law ΔU = Q - W, W = ∫ P dV, isobaric W = P ΔV, isothermal W