A thin bar magnet of length 2 l and breadth 2 b pole strength m and magnetic moment M is divided into four equal parts with length and breadth of each part being half of original magnet.
Then, the magnetic moment of each part is

Options

A. m
B. `m//2`
C. `2m`
D. `m//4`

Answer

b

Explanation

(b) As breath of each part is half the original breadth, therefore, pole strength becomes half (i.e.m/2).