An inductor of reactance 100Ω and resistor of resistance 100Ω are joined in series and connected by AC source of emf 220 V. Power dissipated in the circuit is
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 242 W
The total impedance (Z),
$Z=\sqrt{R^2+{X_L}^2}$
$=\sqrt{100^2+100^2}$
$=\sqrt{20000}=141.42Ω$
Power factor, $\cos\phi=\frac{R}{Z}=\frac{100}{141.42}=0.707$
$I_{rms}=\frac{V_{rms}}{Z}=\frac{220}{141.42}=1.555A$
Power, $P=V_{rms}×I_{rms}×\cos\phi$
$=220×1.555×0.707=242.0W$