Two coils `A` and `B` are connected in series across a `240V ,50 `Hz supply The resistance of A is `5Omega` and the inductance of `B` is 0.02 H The power factor is `0.75` The impedance of the circuit is (if power consumed is 3kW) .
A. `0.144Omega`
B. `1.44Omega`
C. `14.4Omega`
D. `144Omega`

6 views

1 Answers

Correct Answer - C
`overline(P)=e_(rms)I_(rms)cosphi`
`=e_(rms)(e_(rms))/(Z)cosphi`
`therefore Z=(e_(rms)e_(rms)cosphi)/(overline(P))`
`=(240xx240xx0.75)/(3xx10^(3))`
`=14.4Omega`

6 views

Related Questions