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How can Electrical Power be Calculated?

To calculate the power of a component we need to

measure
the voltage
across the component

and the
current
flowing through the component.

We can show how to calculate
power using a
lamp

(an electric
light). The circuit below

shows where to place an ammeter and a voltmeter.

Power = voltage x current P = V x I

If the ammeter reads 2 A and the voltmeter reads 6 V

then P = V x I

= 6 x 2

= 12 watts.

The power of the lamp above is 12 watts.

The same method can be used

to
calculate the power of any component.

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