The compressed air requirements of a manufactur ing facility are met by a 120-hp compresso...

The compressed air requirements of a manufactur ing facility are met by a 120-hp compressor that draws in air from the outside through an 9-m-long, 22-cm-diameter duct made of thin galvanized iron sheets. The compressor takes in air at a rate of 0.27 m³/s at the outdoor conditions of 15°C and 95 kPa. Disregarding any minor losses, determine the useful power used by the compressor to overcome the fric tional losses in this duct.