1. A cylinder/piston contains 100 L air at 110 kPa, 25?C. The air is compressed in a reversible polytropic process to a final state of 800 kPa, 500 K. Assume the heat transfer is with the ambient at 25?C and determine the polytropic exponent n and the final volume of the air. Find the work done by the air, the heat transfer, and the total entropy generation for the process.
2. A room at 22?C is heated electrically with 1500 W to keep a steady temperature. The outside ambient is at 5?C. Find the flux of S (=Q? /T) into the room air, into the ambient, and the rate of entropy generation.
3. A mass of 3 kg nitrogen gas at 2000 K, V = C, cools with 500 W. What is dS/dt?