In an AC circuit, what is the term used for the product of voltage and current?

The product of voltage and current in an AC circuit is referred to as apparent power. This concept is critical in understanding how power is used in alternating current systems. Apparent power is measured in volt-amperes (VA) and represents the total power flowing in the circuit, comprising both the real power that performs work and the reactive power that does not perform work but is necessary for maintaining the electric and magnetic fields in inductive or capacitive components.

In AC circuits, voltage and current can be out of phase due to reactive components, causing part of the power not to do useful work. However, the multiplication of voltage and current still provides a measure of the total power available, irrespective of phase differences.

While real power refers to the actual power consumed by the circuit (measured in watts) and reactive power refers to the power stored and released by inductors and capacitors (measured in reactive volt-amperes), apparent power combines these aspects and gives a comprehensive overview of power in the system.

Understanding the distinction between these various types of power is crucial for proper circuit analysis and ensures more efficient usage of electrical energy in practical applications.