When work is done on an object, energy is transferred. Power is the amount of work done in one second. Efficiency is a measure of how much useful energy is converted.
Part ofCombined ScienceEnergy
When workcloseworkEnergy transferred by a force. Work done = force × distance moved in the direction of the force. is done on an object, energy is transferred.
Energy transferred = work done, and so we can also say:
Power is the amount of work done in one second.
Power is measured in watts (W).
Power can be calculated using either of these equations:
power = \(\frac{\text{work done}}{\text{time taken}}\)
work = power x time taken
time taken = \(\frac{\text{work done}}{\text{power}}\)