GCSE Physics

More Electrical Power

Here's our new equation: P = I² × R

So, if we know the resistance of something, and the current through it, we can work out its power (the energy output from it each second).

e.g. A 10 ohm resistor has a 2 amp current through it.
It's power output is:

P = × R = × 10 = 40 W

It's as simple as that!

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