COMEDK · Physics · 20. Magnetic Properties of Matter
A bar magnet is held perpendicular to a uniform field. If the couple acting on the magnet is to be halved, by rotating it, the angle by which it is to be rotated is
- A \(45^{\circ}\)
- B \(60^{\circ}\)
- C \(90^{\circ}\)
- D \(30^{\circ}\)
Answer & Solution
Correct Answer
(B) \(60^{\circ}\)
Step-by-step Solution
Detailed explanation
The torque acting on a bar magnet in a uniform magnetic field is given by \(\tau = MB \sin \theta\), where \(M\) is the magnetic moment, \(B\) is the magnetic field, and \(\theta\) is the angle between the magnetic moment vector and the magnetic field vector. Initially, the…
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