What is the formula for electrical power?

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Multiple Choice

What is the formula for electrical power?

Explanation:
Power is the rate at which energy is transferred in a circuit, so it’s defined by multiplying voltage by current. That gives P = V × I, with the unit watts. This makes intuitive sense: the higher the voltage pushing charge and the more charge flowing per second, the more energy per second is delivered. If you know current and resistance, you can rewrite the same idea as P = I^2 R, and if you know voltage and resistance, P = V^2 / R. These forms come from the relation V = IR (Ohm’s law) and all describe the same power quantity. The other expressions don’t represent power in general: P = IR would yield a voltage (not power), and P = V/I would yield a resistance (not power).

Power is the rate at which energy is transferred in a circuit, so it’s defined by multiplying voltage by current. That gives P = V × I, with the unit watts. This makes intuitive sense: the higher the voltage pushing charge and the more charge flowing per second, the more energy per second is delivered.

If you know current and resistance, you can rewrite the same idea as P = I^2 R, and if you know voltage and resistance, P = V^2 / R. These forms come from the relation V = IR (Ohm’s law) and all describe the same power quantity.

The other expressions don’t represent power in general: P = IR would yield a voltage (not power), and P = V/I would yield a resistance (not power).

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