Work
Work
Work measures the energy transfered by a system. Work is done when a force moves an object through a distance in the direction of the force. Work is measured in joules and calculated as:
$$ \text{Work} = \text{Force} \times \text{Distance} $$
Work is done when a force is applied and the object moves in the same direction as the force.
Work is NOT done when you push but nothing moves or the force is perpendicular to the motion (e.g. holding a weight still).
Simple machines have work in, and work out. Work out is called useful work.
A load is lifted vertically using a pulley system. The lifting force applied is 120 N, and the load moves 2.5 m upward.
Calculate the work done on the load.
A pulley system is used to lift a load.
The input force applied is 120 N
The input distance moved is 5 m
The output force on the load is 300 N
The output distance the load moves is 2 m
a) Calculate the work in
b) Calculate the work out