What is the unit of active power in electrical circuits?

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Multiple Choice

What is the unit of active power in electrical circuits?

Active power is the rate at which electrical energy is actually converted into useful work in a circuit. In SI units, this real power is measured in watts. For direct current (or for AC with voltage and current in phase), power equals voltage times current (P = VI), so one watt equals one volt multiplied by one ampere. When voltage and current aren’t perfectly aligned in AC, you multiply VI by the cosine of the phase angle (P = VI cos(phi)), but the unit remains the watt. The other quantities—current (amps), voltage (volts), and resistance (ohms)—describe other properties of the circuit, not the rate of energy transfer.

Active power is the rate at which electrical energy is actually converted into useful work in a circuit. In SI units, this real power is measured in watts. For direct current (or for AC with voltage and current in phase), power equals voltage times current (P = VI), so one watt equals one volt multiplied by one ampere. When voltage and current aren’t perfectly aligned in AC, you multiply VI by the cosine of the phase angle (P = VI cos(phi)), but the unit remains the watt. The other quantities—current (amps), voltage (volts), and resistance (ohms)—describe other properties of the circuit, not the rate of energy transfer.

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