2. A winch is a mechanical lifting or hauling device consisting of a rope, cable, or chain winding around a horizontal rotating drum, turned by a crank or by motor or other power source. We use one at our cottage to move heavy things like fallen trees. a) A motor on an electric winch is only 45% efficient. How much work must be done to winch a 200 kg load of bricks up 4 floors on a construction site if each floor is 4.0 m? C b) What power must the motor generate to accomplish this in 42 s