When a coil is connected across a $20$ V dc supply, it draws a current of $5$ A. When it is connected across $20$ V, $50$ Hz ac supply, it draws a current of $4$ A. The self inductance of the coil is ________ mH. (Take $\pi=3$)

JEE Main 2024 · PhysicsNumerical answerNumerical valueMediumMulti-step

JEE Main 9 April 2024, Shift 1, Physics Q58

Question 58 of 90 in this shift, Physics question 28 of 30, Section B.

When a coil is connected across a

20

V dc supply, it draws a current of

5

A. When it is connected across

20

50

Hz ac supply, it draws a current of

4

A. The self inductance of the coil is ________ mH. (Take

\pi=3

)

Official answer

NTA final key.

Chapter: Alternating Current
Topic: Phasor Diagrams
Idea tested: Real Inductor (Choke Coil) Phasors

Same idea in other shifts

Asked 4× in all

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.