One kg of air initially at 7 bar pressure and 360 k temperature expands poly tropically (pvL2 = const.) until the pressure reduced to 1.4 bar. Determine: a)Final specific volume and temperature b)Change of internal energy c)Work done and heat interaction. d)Change in entropy.

1) Air is compressed under Constant Entropy Process from 10 Psia, 3 ft3, 90°F to 50 Psia. Find the following:       a) Final volume in ft3.       b) Final temperature in °F.       c) Work non-flow in BTU. From the problem above use all PVT values, What if the 1lbm of air is compressed under quasi-static process (n=1.27). Find the following:       d) Work non-flow in BTU.       e) Heat in BTU.

2. A tank contains 1 kg mass gas whose density is 700 kg/m3. The pressure is increased from 1 bar to 3 bar. The approximate specific boundary work of the system is a. Cannot be find since some data is missingb. 285 kJ/kgc. 0 kJ/kgd. 0.285 kJ/kg

For open systems, entropy can be transferred by a) heat transfer only. b) mass transfer only. c) both heat and mass transfer.