JEE Main 2021 · PhysicsMultiple choiceSingle correctMediumMulti-step

JEE Main 4 August 2021, Shift 1, Physics Q14

Question 14 of 90 in this shift, Physics question 14 of 30, Section A.

The magnetic field in any region is given by

\vec{B}=B_0\left(2+\frac{x}{a}\right)\hat{k}

. A square loop of edge length ‘l’ is placed with its edge along x and y axis. The loop is moved with a constant velocity

\overline{v}=v_0\hat{i}

. The emf induced in the loop will be -

(1)zero
(2) $v_0B_0\ell$
(3) $v_0B_0\frac{\ell^2}{a}$ Official answer
(4) $v_0B_0\frac{\ell^2}{2a}$

Official answer

Option 3

NTA final key.

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

Same idea in other shifts

Asked 7× in all

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26 Feb 2021, Shift 2 · Q7An aeroplane, with its wings spread 10 m, is flying at a speed of 180 km/h in a horizontal direction. The total intensity of earth’s field…MediumSingle 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.