What is true power?

True power, often represented as "P," measures the actual power consumed by a load in an electrical circuit to perform useful work, such as lighting a bulb or running a motor. It is measured in watts (W) and reflects the amount of energy converted into another form, typically mechanical energy, heat, or light.

In AC circuits, true power is the result of both the voltage and current in the circuit while factoring in the phase difference between them, which is crucial for understanding how efficiently the electrical energy is used. This distinguishes true power from apparent power, which is measured in volt-amperes (VA) and considers both the real power being used and the reactive power within the circuit, which does not perform any real work.

Therefore, stating that true power is the power that does work captures its essence perfectly, explaining it as the useful energy component that directly contributes to the performance of electrical devices.