Question

Magnetic moment of bar magnet is \( M \). The work done to turn the magnet by 90° of magnet in direction of magnetic field \( B \) will be:

• A. zero
• B. \( \frac{1}{2} MB \)
• C. \( 2 MB \)
• D. \( MB \)

Hint:

The work done to rotate a magnetic moment in a magnetic field is given by \( W = -M B \cos \theta \).

Answer 1

The Correct Option is B