1. an ideal gas expands at a constant pressure of 6.00 105 pa from a volume of 1.00 m3 to a volume of 4.00 m3 and then is compressed to one-third that pressure and a volume of 2.50 m3 as shown in the figure below before returning to its initial state. how much work is done in taking a gas through one cycle of the process shown in the figure?
2. the work done by an engine equals one-fourth the energy it absorbs from a reservoir.
(a) what is its thermal efficiency?
(b) what fraction of the energy absorbed is expelled to the cold reservoir?