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 |
Zero 242 W 346 W 141 W |
242 W |
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, $P=V_{rms}×I_{rms}×\cos\phi$ $=220×1.555×0.707=242.0W$ |