Engineering, 26.03.2020 22:04 AutumnJoy12

An insulated 40 ft3 rigid tank contains air at 50 lbf/in2 and 120oF. A valve connected to the tank is now opened, and air is allowed to escape until the pressure inside drops to 25 lbf/in2. The air temperature within the tank and at the exit during this process is kept constant at 120oF by an electric heater placed in the tank. Determine the electrical work [Btu] for the process. Assume that the air behaves like an ideal gas.

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An insulated 40 ft3 rigid tank contains air at 50 lbf/in2 and 120oF. A valve connected to the tank i...

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