Question

A long thin magnet of moment M is bent into a semi circle. The decrease in the Magnetic moment is

• A. $2M/\pi$
• B. $\pi M/2$
• C. $M(\pi -2)/\pi$
• D. $M(2-\pi )/2$

Answer 1

Answer: (D)

$M=\frac{2M}{\pi }$ decrease in magnetic moment
= $M-\frac{2M}{\pi }$