An arc lamp requires a direct current of 10 A at 80 V to function. If it is connected to a 220 V (rms), 50 Hz AC supply, the series inductor needed for it to work is close to :

Engineering

Physics

AC Circuit Analysis

Question

80 H

0.044 H

0.065 H

0.08 H

LiveFree JEE Main Previous Year Online Papers Live Free JEE Advance Previous Year Online Papers

College PredictorLive

Know your College Admission Chances Based on your Rank/Percentile, Category and Home State.

Get your JEE Main Personalised Report with Top Predicted Colleges in JoSA

$R = \frac{V}{I} = \frac{80}{10} = 8$

$10 = \frac{220}{\sqrt{X_{L}^{2} + 8^{2}}}$

$X_{L}^{2} + 8^{2}$ = 22 × 22

$X_{L}^{2}$ = 22² – 8²

X_L = $\sqrt{30 \times 14}$

L = $\sqrt{420}$

L = $\frac{\sqrt{420}}{2 \times 3 .14 \times 50}$

L = $\frac{3 .263}{50} H$

= 0.065 H

i_rms × 8 = 80

i_rms = 10