Choose a wire rope for a vertical mine hoist to lift a load of 55 KN from a depth 300 meters. A rope speed of 500 meter/min is to be attained in 10 seconds.
A multi -disk clutch consists of steel and bronze plates. It transmits 15 KW at 1400 r.p.m. The outer and inner diameters of contacting surface are 100 mm and 200 mm respectively. The coefficient of friction is 0.15 and the permissible intensity of pressure is 0.5N/mm2. Determine the number of steel and bronze disks, simplify the theory used.