JEE Mains · Physics · STD 12 - 5. Magnetism and matter
Two bar magnets oscillate in a horizontal plane in earth's magnetic field with time periods of \(3\,s\) and \(4\,s\) respectively. If their moments of inertia are in the ratio of \(3: 2\) then the ratio of their magnetic moments will e.
- A \(2: 1\)
- B \(8: 3\)
- C \(1: 3\)
- D \(27: 16\)
Answer & Solution
Correct Answer
(B) \(8: 3\)
Step-by-step Solution
Detailed explanation
\(T =2 \pi \sqrt{\frac{ I }{ MB _{ H }}}\) \(\frac{ T _{1}}{ T _{2}}=\frac{2 \pi \sqrt{\frac{ I _{1}}{ M _{1} B _{ H }}}}{2 \pi \sqrt{\frac{ I _{2}}{ M _{2} B _{ H }}}}=\frac{3}{4}\) \(\sqrt{\frac{ I _{1}}{ I _{2}}} \times \frac{ M _{2}}{ M _{1}}=\frac{3}{4}\)…
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