A cylinder-piston apparatus contains 29 kg of air at 30°C. Weights on the piston fix the initial pressure at 20 bar. Find the work done if: a. Some of the weights are quickly removed until external pressure is 5 bar. The temperature remains constant. b. Some of the weights are slowly removed until the external pressure reaches 5 bar. The temperature remains constant. c. The expansion from 20 bar to 5 bar is polytropic, with an exponent of 1.4. Note that if the gas is ideal and PV = constant, then the temperature varies as: 7-11-190 T₁

A cylinder-piston apparatus contains 29 kg of air at 30°C. Weights on the piston fix the initial pressure at 20 bar. Find the work done if: a. Some of the weights are quickly removed until external pressure is 5 bar. The temperature remains constant. b. Some of the weights are slowly removed until the external pressure reaches 5 bar. The temperature remains constant. c. The expansion from 20 bar to 5 bar is polytropic, with an exponent of 1.4. Note that if the gas is ideal and PV = constant, then the temperature varies as: 7-11-190 T₁

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 30RQ: A gas is compressed inside a compressor's cylinder. When the piston is at its bottom dead center,...

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