Physics - Magnetism Question with Solution | TestHub

Magnetic length is the minimum distance between the north pole and the south pole, which is decreased in the second case.

${\mathrm{M}}^{\mathrm{\prime }}=\frac{2\mathrm{M}}{\mathrm{\pi }}$, decrease in magnetic moment

$=\mathrm{M}-\frac{2\mathrm{M}}{\mathrm{\pi }}$