The full form of pf is Power Factor. It’s used on Academic & Science ,Electrical in Worldwide

Power Factor (pf) is defined as the ratio of the Real Power (KW) to Apparent Power (KVA). It can also be defined as the cosine that represents the phase angle between the current and voltage waveforms. Real Power (KW, also called Actual Power or Active Power) is the working power and is the power that actually powers the equipment and performs useful work. The Reactive Power (KVAR) is the power that magnetic equipment like transformer, motor and relay needs to produce the magnetizing flux. The Apparent Power (KVA) is the “vectorial summation” of KVAR and KW. The power factor can vary between 0 and 1, and can be either inductive or capacitive. When the current and voltage wave-forms are in phase, the power factor is 1.