A magnetised wire of moment M and length l is bent in the form of a semicircle of radius r . Then its new magnetic moment is

Question

A magnetised wire of moment M and length l is bent in the form of a semicircle of radius r . Then its new magnetic moment is, 2 M π, 2 M, M π, zero

MARKS App · Accepted Answer

On bending a wire its pole strength remains unchanged whereas its magnetic length changes. New magnetic moment, M ' = m × 2 r = m × 2 l π = 2 M π