Electrical power

2 marks · Normal

State the equation linking power, current, and voltage. Define what each of the symbols stands for.

Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.

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P = I × V; P = power (W), I = current (A), V = voltage (V)

Must show: Equation P = I × V, Each symbol correctly defined

Also accept: Accept use of 'potential difference' for V

Common mistakes: Incorrect units

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Marking points

B1 · 1 mark · Writes correct equation.

B2 · 1 mark · Defines all symbols, including correct units.

Worked solution

Where P = power in watts (W), I = current in amperes (A), V = voltage (V).