Work, Energy and Power

Energy (Also seen in GCSE Physics 1)

We already know that it appears in a number of different forms and may be transformed from one form to another. But what is energy? Energy is the ability to do work.

We can say that the work done is equal to the energy transferred  W=E

Work done = energy transferred

 

Work Done (Also seen in GCSE Physics 2)

In Physics we say that work is done when a force moves through a distance and established the equation

Work Done = Force x Distance moved in the direction of the force        W=Fs

Work Done is measured in Joules, J

Force is measured in Newtons, N

Distance is measured in metres, m

The distance moved is not always in the direction of the force. In the diagram we can see that the block moves in a direction that is q away from the ‘line of action’ of the force. To calculate the work done we must calculate the distance we move in the direction of the force or the size of the force in the direction of the distance moved. Both of these are calculated by resolving into horizontal and vertical components.

Work Done = Force x Distance moved in the direction of the force

Work Done = Size of Force in the direction of movement x Distance moved