What is the formula for calculating power factor?

The formula for calculating power factor is based on the cosine of the phase angle between the voltage and current in an AC circuit. Power factor represents the efficiency of power usage in an electrical system and is crucial for understanding how effectively electrical power is being converted into useful work output.

When voltage and current are out of phase due to inductive or capacitive loads, the power factor will indicate how much of the total power is being used effectively. By using the cosine of the phase angle, you can derive the power factor value, which ranges from 0 to 1. A power factor of 1 (or unity) indicates that all the power is being converted into work, whereas lower values represent less efficient power usage.

Other formulas mentioned do not accurately represent power factor: the sine function would give you the reactive power component, the tangent function relates to the ratio of reactive power to real power, and the inverse function presented does not relate to power factor calculation. Therefore, using the cosine of the phase angle accurately calculates the power factor in electrical systems.