A bar magnet of magnetic moment is divided into '' equal parts by cutting parallel to length. Then one part is suspended in a uniform magnetic field of strength and held making an angle with the direction of the field. When the magnet is released, the kinetic energy of the magnet in the equilibrium position is:
Answer is A
Net magnetic moment after cutting
We know that,
In
equilibrium position, all the potential energy will be converted
into kinetic energy i.e.
Given
Therefore,