Two identical short bar magnets, each having magnetic moment of `10Am^(2)`, are arranged such that their axial lines are perpendicular to each other and their centres be along the same straigh line in a horizonetal plane. If the distance between their centres is `0.2m`, the resultant magnetic induction at a point midway between them is
`(mu_(0)=4pixx10^(-7)Hm^(-1))`

Options

A. `sqrt2 xx 10^(-7)` tesla
B. `sqrt5 xx 10^(-7)` tesla
C. `sqrt2 xx 10^(-3)` tesla
D. `sqrt5 xx 10^(-3)` tesla

Answer

D

Explanation

`B_("net") = sqrt(B_(a)^(2) + B_(e)^(2))`
`= sqrt(((mu_(0))/(4pi).(2M)/(d^(3)))^(2) + ((mu_(0))/(4pi) (M)/(d^(3)))^(2))`
`= sqrt5. (mu_(0))/(4pi).(M)/(d^(3))= sqrt5 xx 10^(-7) xx (10)/((0.1)^(3)) = sqrt5 xx 10^(-3)T`