The thing is I can't really tell what is going to remain constant when I read the question. I think the pressure remains constant and I know mass does which leaves me with Ti/Vi = Tf/Vf. I've already got Vi and Tf but I don't really know what to do with that.
Homework Statement
Two pounds of air contained in a cylinder expand without friction against a piston. The pressure on the back side of the piston is constant at 200 psia. The air initially occupies a volume of 0.5 ft3. What is the work done by the air in ft-lbf if the expansion continues until...