CP Fitters' Phase 2 Apprenticeship Training

Power is a measure of the rate at which work is done.

Work done = Force x Distance measured in Nm

If we measure this work done  per second, we are measuring power.

1 watt of power is work done at the rate of 1Nm/s

Power is measured in Watts. The unit of measurement gets its name from James Watt.

Power in terms of electricity

In electrical terms, you can think of power as the rate at which energy is converted.

W = I x V

Think of it this way, a 2W interior lamp in a vehicle is not as powerful as a 60W headlamp.

This means that that the 2W interior lamp will convert chemical energy in the battery into heat energy at the lamp at a much slower rate than the 60W headlamp.

In other words, the 60W headlamp will flatten the battery much faster than the 2W interior lamp, because the headlamp is more powerful.

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