Q.
Two magnets of equal magnetic moments $M$ each are placed as shown in figure. The resultant magnetic moment is
A) $M$
B) $\sqrt{3}M$
C) $\sqrt{2}M$
D) $M/2$
Explanation
(a) As magnetic moments are directed along $SN,$ angle between $\overrightarrow{M}$ and $\overrightarrow{M}\ $is $\theta = 120{^\circ}$
$\therefore$ Resultant magnetic moment
$= \sqrt{M^{2} + M^{2} + 2M\ M\cos{120{^\circ}}}$
$= \sqrt{M^{2} + M^{2} + 2M^{2}( - 1}/2) = M$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.