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A gas initially at 500°C, 1 MPa is contained in a piston-cylinder arrangement with an initial volume of 0.1 m^3. It is then slowly expanded according to the relation PV = constant until a final pressure of 100 kPa is attained. Determine the work for this process.

A gas initially at 500°C, 1 MPa is contained in a piston-cylinder arrangement with an initial volume of 0.1 m^3. It is then slowly expanded according to the relation PV = constant until a final pressure of 100 kPa is attained. Determine the work for this process. Correct Answer 230.3 kJ

Process: PV = C ⇒ V2 = P1V1/P2 = 1000 × 0.1/100 = 1 m^3 1W2 = ∫ P dV = ⌠ CV^(-1)dV = C ln(V2/V1) 1W2 = P1V1 ln(V2/V1) = 1000 × 0.1 ln (1/0.1) = 230.3 kJ.

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