Question

The impedance of a circuit consists of $3ohm$ resistance and $4ohm$ reactance. The power factor of the circuit is

• A. 0.4
• B. 0.6
• C. 0.8
• D. 1.0

Answer 1

Answer: (B)

$Z=\sqrt{R^2+X^2}$
$=\sqrt{4^2+3^2}=5\Omega$
$\therefore \cos \varphi =\frac{R}{Z}=\frac{3}{5}=0.6$