1. A piston/cylinder arrangement has a load on the piston, so it maintains constant pressure. It contains 1 kg of steam at 500 kPa, 50% quality. Heat from a reservoir at 700?C brings the steam to 600?C. Find the second-law efficiency for this process. Note that no formula is given for this particular case, so determine a reasonable expression for it.
2. A jet of air at 200 m/s flows at 25?C, 100 kPa toward a wall, where the jet flow stagnates and leaves at very low velocity. Consider the process to be adiabatic and reversible. Use the exergy equation and the second law to find the stagnation temperature and pressure.
