Q. The magnetic moment of a current (i) carrying circular coil of radius ($r$) and number of turns ($n$) varies as
A) 1/$r^{2}$
B) 1/$r$
C) $r$
D) $r^{2}$
Explanation
(d) $M = niA = ni(\pi r^{2}) \Rightarrow M \propto r^{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.