An insulated 8-m' rigid tank contains air at 800 kPa and 67°C. A valve connected to the tank is now opened, and air is allowed to escape until the pressure inside drops to 400 kPa. The air temperature during this process is maintained constant by an electric resistance heater placed in the tank. Determine (a) The initial, the final and the exit masses of air in the tank (b) the electrical energy supplied during this process and (c) the total entropy change. The gas constant is R 0.287 kPa.m/kg.K (Table A-1). Using the properties of air from (Table A-17). Assuming a constant average pressure of (800 + 400)/2 = 600 kPa for the exit stream %3D %3D

An insulated 8-m' rigid tank contains air at 800 kPa and 67°C. A valve connected to the tank is now opened, and air is allowed to escape until the pressure inside drops to 400 kPa. The air temperature during this process is maintained constant by an electric resistance heater placed in the tank. Determine (a) The initial, the final and the exit masses of air in the tank (b) the electrical energy supplied during this process and (c) the total entropy change. The gas constant is R 0.287 kPa.m/kg.K (Table A-1). Using the properties of air from (Table A-17). Assuming a constant average pressure of (800 + 400)/2 = 600 kPa for the exit stream %3D %3D

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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