A bar magnet of length 0.1m has pole strength of 50A-m. Calculate the magnetic field at distance of 0.2m from tis centre on
(i) its axial line and (ii) it equatorial line.

Explanation

Length of the magnet `,2l=0.1 m or l = 0.05 m`
Distance of the point on equatorial line , d = 0.2 m
Pole strength , m = 50 Am
Magnetic induction on the equatorial line of a bar magnet is ,
` B = (mu_0)/(4pi) ( m)/((d^(2) + l^(2))^(3//2))=(mu_0)/(4pi)(m(2l))/((d^(2) + l^(2))^(3//2))`
`B=(4pi xx 10^(-7))/(4pi) xx (50 xx 0.1)/([(0.2)^(2) + (0.05)^(2)]^(3//2))`
`=5.7 xx 10^(-5)T`