An inductor and a resistor are connected to an ac supply of 120 V, 50 Hz. The resistance of the resistor is 20Ω. If the voltages leads the current by a phase difference of 45°, find the inductance of the inductor. &lt;!-- [if !supportLineBreakNewLine]--&gt; &lt;!--[endif]--&gt;

63.7mH

40mH

66.7mH

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Alternating Current Overview Physics Alternating Current Physics Class 12th

An inductor and a resistor are connected to an ac supply of 120 V, 50 Hz. The resistance of the resistor is 20Ω. If the voltages leads the current by a phase difference of 45°, find the inductance of the inductor.

Option 1 -

40mH

Option 2 -

63.7mH

Option 3 -

66.7mH

Option 4 -

133.3mH

2 Views | Posted a month ago

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1 Answer

Answered by

Vishal Baghel | Contributor-Level 10

a month ago

Correct Option - 2

Detailed Solution:

X? = X? ⇒ ωL = R ⇒ 2 × 3.14 × 50 × L = 20 ⇒ L = 63.7mH

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