Explain the term 'power factor'.

The term 'power factor' defines the efficiency with which electrical power is converted into useful work output, specifically in AC (alternating current) electrical systems. It is calculated as the ratio of real power, which is the actual power consumed by the load to perform useful work, to apparent power, which represents the total power flowing in the circuit.

Expressed mathematically, power factor can be represented as:

Power Factor = Real Power (Watts) / Apparent Power (Volt-Amperes)

This ratio ranges from 0 to 1, where a power factor of 1 indicates that all the power supplied is being used effectively for work. When the power factor is less than 1, it implies that some of the power is reactive, which does not contribute to doing any useful work. Therefore, a higher power factor signifies a more efficient system, while a lower power factor indicates wasted electrical energy.

Understanding power factor is crucial for efficient energy management and can impact billing, system stability, and overall electrical efficiency.