Answer Posted / eraks
wenever v supply power (S) to a load den it gets divided into two parts namely active/real/true power (P) and reactive power(Q) depending on the type of load.
so v can say S= P+Q vectorially &
P = S cos#
Q = S sin#
where S is supply power or apparent power.
=> cos# = P/S i.e. ratio of true power and apparent power.THIS is POWER FACTOR.
Its value lies btwn (-1) to ( +1)
power factor is negative wen direction of flow of power
gets reversed i.e. from load to supply or v can say it may b the case due to ferranti effect.
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