Q. The areas of cross-section of three magnets of same length area $A,2\ A\ and\ 6A$ respectively. The ratio of their magnetic moments will be
A) 6 : 2 : 1
B) 1 : 2 : 6
C) 2 : 6 : 1
D) 1 : 1 : 1
Explanation
(b) As magnetic moment $\propto$ pole strength $\propto$ area of cross section and $M\ \propto m\ \propto A$
$M_{1}\ :M_{2}\ :M_{3} = 1\ :2\ :6$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.