Air is contained in a vertical piston-cylinder assembly fitted with an electrical resistor. The atmosphere exerts a pressure of 101.325 kPa on the top of the piston, which has a mass of 50 kg and a face area of 0.10 m². Electric current passes through the resistor, and the volume of the air slowly increases by 2 ft while its pressure remains constant. The mass of the air is 0.32 kg, and its specific internal energy increases by 20 Btu/lb. The air and piston are at rest initially and finally. The piston-cylinder material is a ceramic composite and thus a good insulator. Friction between the piston and cylinder wall can be ignored, and the local acceleration of gravity is g = 32.0 ft/s Determine the heat transfer from the resistor to the air, in Btu, for a system consisting of (a) the air alone, (b) the air and the piston. Also draw the schematic diagram.

Air is contained in a vertical piston-cylinder assembly fitted with an electrical resistor. The atmosphere exerts a pressure of 101.325 kPa on the top of the piston, which has a mass of 50 kg and a face area of 0.10 m². Electric current passes through the resistor, and the volume of the air slowly increases by 2 ft while its pressure remains constant. The mass of the air is 0.32 kg, and its specific internal energy increases by 20 Btu/lb. The air and piston are at rest initially and finally. The piston-cylinder material is a ceramic composite and thus a good insulator. Friction between the piston and cylinder wall can be ignored, and the local acceleration of gravity is g = 32.0 ft/s Determine the heat transfer from the resistor to the air, in Btu, for a system consisting of (a) the air alone, (b) the air and the piston. Also draw the schematic diagram.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter2: Matter And Energy

Section: Chapter Questions

Problem 17RQ: At a constant pressure, how does a volume of gas vary with respect to the absolute temperature?

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