Time period of vibration, T=2πMB1 Where ℓ= moment of inertia of magnet, M= magnetic moment I=12mℓ2 and M= pole strength ×ℓ I′=121(3m)(3ℓ)2×3=9l and M′= pole strength (will remain the same) ×(ℓ/3)×3=M. T′=9T=92 s.
JEE Main 2004 — Physics Electromagnetism
The length of a magnet is large compared to its width and breadth. The time period of its width and breadth. The time period of its oscillation in a vibration magnetometer is 2 s. The magnet is cut along its length into three equal parts and three parts are then placed on each other with their like poles together. The time period of this combination will be
Held on 30 Apr 2004 · Verified 6 Jul 2026.
2 s
2/3 s
23 s
2/3 s
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