When calculating Reactive Power, which trigonometric function is used?

When calculating Reactive Power in an AC electrical system, the sine function is utilized because it relates to the phase difference between voltage and current. Reactive Power (measured in VARs) arises in circuits with inductors and capacitors, where there is a phase shift between the voltage and current waveforms. This phase shift can be represented by the angle (\phi).

In this context, Reactive Power is given by the formula Q = V * I * sin(φ), where Q is the Reactive Power, V is the voltage, I is the current, and φ is the phase angle. The sine function here captures the relationship between the current and voltage that leads to the generation of reactive power, confirming that energy is being stored and then released by the inductive or capacitive components in the circuit, rather than being consumed as active power.

Understanding this relationship is critical for effectively managing electrical systems, especially when it comes to optimizing the power factor and ensuring efficient energy use in both residential and industrial applications.