Answer / pradhyumn

Ideal Power factor is 1.
It is ratio of real power(measured in watts) flowing to the
load to apparent power(measured in VA). It ranges between 0
to 1.

P.F. is a measure of the degree to which a given load
matches to that of a pure resistance.

P.F.=1 if load is purely resistive.
P.F.=0 if load is inductive or capacitive or both.

For RL-circuit P.F. is between 0&1.(lagging)
For RC-circuit P.F. is between 0&1.(leading).

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A circuit breaker is a

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