A piston/cylinder contains air at 100 kPa, 300 K. A reversible polytropic process with n = 1.3 brings the air to 500 K. Any heat transfer if it comes in is from a 325°C reservoir and if it goes out it is to the ambient at 300 K. Find the specific work.

A piston/cylinder contains air at 100 kPa, 300 K. A reversible polytropic process with n = 1.3 brings the air to 500 K. Any heat transfer if it comes in is from a 325°C reservoir and if it goes out it is to the ambient at 300 K. Find the specific work. Correct Answer -191.3 kJ/kg

Process : Pv^(n) = C Work = ⌠PdV = (P2V2 – P1V1)/(1-n) = R(T2-T1)/(1-n) = 0.287 (500 – 300)/(1 – 1.3) = -191.3 kJ/kg.
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