JEE Main 2023 · PhysicsNumerical answerNumerical valueMediumCalculation

JEE Main 15 April 2023, Shift 1, Physics Q58

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

A 20 cm long metallic rod is rotated with 210 rpm about an axis normal to the rod passing through its one end. The other end of the rod is in contact with a circular metallic ring. A constant and uniform magnetic field 0.2T parallel to the axis exists everywhere. The emf developed between the centre and the ring is __________ mV. Take

\pi = \frac{22}{7}

Official answer

NTA final key.

Chapter: Electromagnetic Induction
Topic: Faraday's Law
Idea tested: Rotational Motional EMF

Same idea in other shifts

Asked 5× in all

5 Apr 2026, Shift 2 · Q36A metal rod of length $L$ rotates about one end at origin with a uniform angular velocity $\omega$ . The magnetic field radially falls off…HardSingle correct
4 Apr 2024, Shift 2 · Q53A rod of length 60 $cm$ rotates with a uniform angular velocity 20 rad $s^{-1}$ about its perpendicular bisector, in a uniform magnetic…MediumNumerical value
30 Jan 2024, Shift 1 · Q58A ceiling fan having 3 blades of length 80 cm each is rotating with an angular velocity of 1200 rpm. The magnetic field of earth in that…MediumNumerical value
26 Jun 2022, Shift 2 · Q44A metallic conductor of length 1m rotates in a vertical plane parallel to east-west direction about one of its end with angular velocity 5…EasySingle correct

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.