JEE Main 2021 · PhysicsNumerical answerNumerical valueMediumCalculation

JEE Main 27 August 2021, Shift 2, Physics Q22

Question 22 of 90 in this shift, Physics question 22 of 30, Section B.

An ac circuit has an inductor and a resistor of resistance R in series, such that

X_L=3\ R

. Now, a capacitor is added in series such that

X_C=2\ R

. The ratio of new power factor with the old power factor of the circuit is

\sqrt{5}:x

. The value of

x

is __________.

Official answer

NTA final key.

Chapter: Alternating Current
Topic: Phasor Diagrams
Idea tested: Power Factor from Phasors

Same idea in other shifts

Asked 9× 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.