Question

A 100 kg object is lifted by a pulley system. Diagram and Calculate the force needed to lift this object given the following systems. Remember to show all your work.

Answer 1

For a single fixed pulley system, it is

Force = Weight = 100 kg * 9.81 m/s^2 = 981 N

For a single moveable pulley system, it is

Force = Weight / 2 = 100 kg * 9.81 m/s^2 / 2 = 490.5 N

For two fixed pulley system, it is

Force = Weight / 4 = 100 kg * 9.81 m/s^2 / 4 = 245.25 N