4.43 A piston/cylinder assembly contains 3 kg of air at 20°C and 300 kPa. It is now heated in a constant pressure process to 600 K. a. Find the final volume. b. Plot the process path in a P-v diagram. c. Find the work in the process.

A piston/cylinder shown in Fig. P3.108 contains 0.5 m3 of R-410A at 2 MPa, 150°C. The piston mass and atmosphere give a pressure of 450 kPa that will float the piston. The whole setup cools in a freezer to –20°C. Find the heat transfer and show the P-v diagram for the process. R-410A Figure P3.108

A constant-pressure piston/cylinder assembly con- tains 0.2 kg of water as saturated vapor at 400 kPa. It is now cooled so that the water occupies half of the original volume. Find the work and heat trans- fer for the process.

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