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A piston-cylinder assembly has initially a volume of 0.3 m3 of air at 25 oC. Mass...

A piston-cylinder assembly has initially a volume of 0.3 m3 of air at 25 oC. Mass of the air is 1 kg. Weights are put on the piston until the air reaches to 0.1 m3 and 1,000 oC, in which the air undergoes a polytropic process (PVn = const). Assume that heat loss from the cylinder, friction of piston, kinetic and potential effects are negligible. 1) Determine the polytropic constant n. 2) Determine the work transfer in kJ for this process, and discuss its direction. 3) Sketch the process in T-V (temperature-volume) diagram.

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