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The average power dissipated in A.C. cir...

The average power dissipated in A.C. circuit is 2 watt. If a current flowing through a circuit is 2 A and impedance is `1 Omega`, what is the power factor of the A.C. circuit ?

A

0.5

B

1

C

0

D

`(1)/(sqrt(2))`

Text Solution

Verified by Experts

The correct Answer is:
A
`P = VI cos phi = I^(2) Z cos phi " "(because V = IZ)`
`cos phi = (P)/(I^(2)Z) = (2)/(4 xx 1) = 0.5`
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