Thermodynamics A paddle wheel stirs 0.2 kg of air contained in a piston-cylinder
ID: 892631 • Letter: T
Question
Thermodynamics
A paddle wheel stirs 0.2 kg of air contained in a piston-cylinder assembly. The air is initially at 400 K. During the process, 15 kJ of heat transfer to the air increases its temperature to 500 K. The air pressure remains constant during the process and changes in kinetic and potential energy are negligible. The air can be treated as an ideal gas, but do not assume constant specific heats. Determine:
a. The work done by the air on the piston, in kJ.
b. The work done by the paddle wheel on the air, in kJ.
Explanation / Answer
a) 5.74 kJ
b) -5.41 kJ