Calculate the power factor of the circuit shown in figure

Question

Calculate the power factor of the circuit shown in figure <img class="img-fluid question-image" alt="Question" src="https://cdn.tardigrade.in/q/nta/p-2x5y5svoqtnf0xep.jpg" /> (A) 0.2 (B) 0.4 (C) 0.8 (D) 0.6

Tardigrade Admin · Accepted Answer

Resistance of the circuit, R=R1+R2=40 Ω+40 Ω=80 Ω Impedance of the circuit, Z=√R2 + (XL - XC)2=√(80)2 + (100 - 40)2 =√(80)2 + (60)2=100 Ω Power factor, cos φ=(R/Z)=(80/100)=0.8

Q. Calculate the power factor of the circuit shown in figure

$0.2$

$0.4$

$0.8$

$0.6$

Resistance of the circuit,
$R = R_{1} + R_{2} = 40 Ω + 40 Ω = 80 Ω$
Impedance of the circuit,
$Z = R^{2} + (X_{L} - X_{C})^{2} = (80)^{2} + (100 - 40)^{2}$
$= (80)^{2} + (60)^{2} = 100 Ω$
Power factor, $cos ϕ = \frac{R}{Z} = \frac{80}{100} = 0.8$