Two identical short bar magnets, each having magnetic moment `M`, are placed a distance of `2d` apart with axes perpendicular to each other in a horizontal plane. The magnetic induction at a point midway between them is

Options

A. `(mu_(0))/(4pi)(sqrt2)(M)/(d^(3))`
B. `(mu_(0))/(4pi)(sqrt3)(M)/(d^(3))`
C. `((2mu_(0))/(pi))(M)/(d^(3))`
D. `(mu_(0))/(4pi)(sqrt5)(M)/(d^(3))`

Answer

d

Explanation

(d) `B_(1)=(mu_(0))/(4pi).(2M)/(d^(3)) and B_(2)=(mu_(0))/(4pi)(M)/(d^(3))`
Now , `B=sqrt((B_(1)^(2)+B_(2)^(2))=sqrt5(mu_(0))/(4pi).(M)/(d^(3))` .