Air contained within a piston-cylinder assembly undergoes three processes in series:
a. Process 1-2: compression at constant pressure from P1=10lbf/in2, V1=4ft3 to state 2
b. Process 2-3:Consant volume heating to state 3, where P3=50lbf/in2
c. Process 3-1: Expansion to the initial state, during which the pressure-volume relationship is PV=constant.
Sketch the process in series on P-V coordinates. Evaluate the (a) volume at state 2, in ft3, (b) work for each process, in Btu.