The inductance of a choke coil is 0.1 H and resistance is 12 Ω . If it is connected to an alternating current source of frequency 60 Hz, then power factor will be

Question

The inductance of a choke coil is 0.1 H and resistance is 12 Ω . If it is connected to an alternating current source of frequency 60 Hz, then power factor will be (A) 0.32 (B) 0.30 (C) 0.28 (D) 0.24

Tardigrade Admin · Accepted Answer

cos φ=(R/Z)=(R/√R2+ω2 L2) =(12/√(12)2+4 × π2 ×(60)2 ×(0.1)2) ⇒ cos φ=0.30

Q. The inductance of a choke coil is $0.1 H$ and resistance is $12 Ω.$ If it is connected to an alternating current source of frequency $60 Hz$ , then power factor will be

0.32

0.30

0.28

0.24

$cos ϕ = \frac{R}{Z} = \frac{R}{R ^{2} + ω ^{2} L ^{2}}$
$= \frac{12}{( 12 ) ^{2} + 4 \times π ^{2} \times ( 60 ) ^{2} \times ( 0.1 ) ^{2}}$
$\Rightarrow cos ϕ = 0.30$

Q. The inductance of a choke coil is 0.1H and resistance is 12Ω. If it is connected to an alternating current source of frequency 60Hz, then power factor will be