The magnetic potential energy, when a magnetic bar of magnetic moment $\vec{m}$ is placed perpendicu

Question

The magnetic potential energy, when a magnetic bar of magnetic moment $\vec{m}$ is placed perpendicular to the magnetic field $\vec{B}$ is

Professor PC Thomas Classes · Answer

(b) : The magnetic potential energy is given by $$ V=-\vec{m} \cdot \vec{B}=-m B \cos 	heta $$ when, $\quad 	heta=90^{\circ} ; V=-m B \cos 90^{\circ}=0$