Air flows steadily at the rate of 0.5 kg/s through an air compressor, entering at 7m/s velocity, 100 kPa pressure, and 0.95 m^{3}/kg volume, and leaving at 5 m/s, 700 kPa, and 0.19 m^{3}/kg. The internal energy of the air leaving is 90 KJ/kg greater than that of the air entering. Cooling water in the compressor jackets absorbs heat from the air at the rate of 58 KW
(a) Calculate the rate of shaft work input to the air in KW
(b) Determine the ratio of the inlet pipe diameter to outlet pipe diameter.