Home/
Competitive Exams/
JEE Main & Advanced/
Physics/
Magnetism/
Question 20211
JEE Physics · Hard

Magnetism: Magnetic Dipole — Oscillation MCQ

Solve this quality-checked JEE multiple-choice question, then review the correct answer and explanation.

Timer-based practiceDetailed answer reviewMobile-friendly flow
Magnetic Dipole — OscillationHardQuestion 20211

Question

A bar magnet of moment m and moment of inertia I oscillates in uniform field B. Its time period is:
  1. A
    2π√(I/mB)
    Correct
  2. B
    2π√(mB/I)
  3. C
    2π√(I/B)
  4. D
    √(mB/I)

Correct answer

2π√(I/mB)

Explanation

Restoring torque = −mB sinθ ≈ −mBθ for small θ. Angular frequency ω = √(mB/I), period T = 2π/ω = 2π√(I/mB).

Review Magnetism notesStart timed chapter practice