In what units is apparent power expressed?

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Multiple Choice

In what units is apparent power expressed?

Explanation:
Apparent power is the product of voltage and current in an AC circuit, taken as the magnitude of the complex power. It is expressed in volt-amperes (VA) because S = V I* and its magnitude |S| equals sqrt(P^2 + Q^2), where P is real power (watts) and Q is reactive power (volt-amps reactive). The real power in watts represents actual energy transfer, while reactive power accounts for energy stored and returned by reactive elements. Because S combines both, its unit is VA. Joules measure energy, not power, and watts (or kilowatts) measure real power, not apparent power. If the power factor is 1, P equals S, but otherwise P < S, so apparent power exceeds real power by the factor 1/cosφ.

Apparent power is the product of voltage and current in an AC circuit, taken as the magnitude of the complex power. It is expressed in volt-amperes (VA) because S = V I* and its magnitude |S| equals sqrt(P^2 + Q^2), where P is real power (watts) and Q is reactive power (volt-amps reactive). The real power in watts represents actual energy transfer, while reactive power accounts for energy stored and returned by reactive elements. Because S combines both, its unit is VA. Joules measure energy, not power, and watts (or kilowatts) measure real power, not apparent power. If the power factor is 1, P equals S, but otherwise P < S, so apparent power exceeds real power by the factor 1/cosφ.

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