5) A mass of 15 kg of air in a piston-cylinder device is heated from 25 to 85°C by passing current through a resistance heater inside the cylinder. The pressure inside the cylinder is held constant at 200 kPa during the process, and a heat loss of 70 kJ occurs. Determine the electric energy supplied, in kWh. (Hint: use the ideal gas model) W₂ Air P= constant

5) A mass of 15 kg of air in a piston-cylinder device is heated from 25 to 85°C by passing current through a resistance heater inside the cylinder. The pressure inside the cylinder is held constant at 200 kPa during the process, and a heat loss of 70 kJ occurs. Determine the electric energy supplied, in kWh. (Hint: use the ideal gas model) W₂ Air P= constant

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 27RQ: How many Btu/h would be produced in a 12-kW electricheater?

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