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 0.2 m2. The volume of the air slowly increases by 0.085 m3 while its pressure remains constant. The mass of the air is 0.45 kg and its specific internal energy decreases by 25 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/s2. Determine the heat transfer from the resistor to the air, in Btu, for a system consisting of the air and the piston.

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 0.2 m2. The volume of the air slowly increases by 0.085 m3 while its pressure remains constant. The mass of the air is 0.45 kg and its specific internal energy decreases by 25 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/s2. Determine the heat transfer from the resistor to the air, in Btu, for a system consisting of the air and the piston.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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