A machine applies a force of 100 Newtons over a distance of 10 meters to raise a 500 newton drum 1.5 meters.  What is the work input?

Expert Answers
thilina-g eNotes educator| Certified Educator

The work input is the total work done by the machine not the effective work.

The effective work done by a machine is the output work.

The ratio between work output and work input gives you the efficiency of the machine.

Therefore the work input here is,

Work input = Input Force x distance

                 = 100 x 10 Nm

                 = 1000 J


Work output = 500 x 1.5 Nm

                  = 750 J


Efficiency     = 750/1000 x 100%

                  = 75 %