Learn

Friday, 9 October

JEE Main 2024 · PhysicsMultiple choiceSingle correctMediumApplication

JEE Main 31 January 2024, Shift 2, Physics Q42

Question 42 of 90 in this shift, Physics question 12 of 30, Section A.

A uniform magnetic field of 2×10−32\times10^{-3} T acts along positive YY-direction. A rectangular loop of sides 20 cm and 10 cm with current of 5 A is in YY-ZZ plane. The current is in anticlockwise sense with reference to negative XX axis. Magnitude and direction of the torque is:
  1. (1)2×10−42\times10^{-4} N-m along positive ZZ-direction
  2. (2)2×10−42\times10^{-4} N-m along negative ZZ-directionOfficial answer
  3. (3)2×10−42\times10^{-4} N-m along positive YY-direction
  4. (4)2×10−42\times10^{-4} N-m along positive XX-direction

Official answer

Option 2

NTA final key.

Chapter
Moving Charges and Magnetism
Topic
Magnetic Dipole Moment
Idea tested
Torque on a dipole in uniform field

Same idea in other shifts

Asked 3× in all
  1. 4 Apr 2026, Shift 2 · Q49A circular coil of radius 2 cm and 125 turns carries a current of 1 A. The coil is placed in a uniform magnetic field of magnitude 0.4 T.…EasyNumerical value
  2. 8 Apr 2026, Shift 2 · Q39A current carrying circular loop of radius 2 cm with unit normal n^=k^+i^2\hat{n} = \frac{\hat{k} + \hat{i}}{\sqrt{2}} is placed in a magnetic…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 42 of the 174 JEE Main shifts held from 2017 to 2026.