An inductor of $10$ mH, capacitor of $0.1\ \mu$F and a resistor of $100\ \Omega$ are connected in series across an $a.c$ power supply $220$ V, $70$ Hz. The power factor of the given circuit is $0.5$. The difference in the inductive reactance and capacitance reactance is $\sqrt3\,\alpha\ \Omega$. The value of $\alpha$ is ______.

JEE Main 2026 · PhysicsNumerical answerNumerical valueMediumCalculation

JEE Main 4 April 2026, Shift 1, Physics Q50

Question 50 of 75 in this shift, Physics question 25 of 25, Section B.

An inductor of

10

mH, capacitor of

0.1\ \mu

F and a resistor of

100\ \Omega

are connected in series across an

a.c

power supply

220

70

Hz. The power factor of the given circuit is

0.5

. The difference in the inductive reactance and capacitance reactance is

\sqrt3\,\alpha\ \Omega

. The value of

\alpha

is ______.

Official answer

100

NTA final key.

Chapter: Alternating Current
Topic: Phasor Diagrams
Idea tested: Impedance Triangle Construction

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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 42 of the 174 JEE Main shifts held from 2017 to 2026.