Two short magnets of equal dipole moments M are fastened perpendicularly at their centre (figure). The magnitude of the magnetic field at a distance d from the centre on the bisector of the right angle is

Options

A. `(mu_(0))/(4pi) (M)/(d^(3))`
B. `(mu_(0))/(4pi) (M sqrt2)/(d^(3))`
C. `(mu_(0))/(4pi) (2 sqrt2M)/(d^(3))`
D. `(mu_(0))/(4pi) (2M)/(d^(3))`

Answer

C

Explanation

`M_("net") = sqrt(M^(2) + M^(2))= sqrt2M`
Point P lies on the axial line of the magnet
`B= (mu_(0))/(4pi).(2 sqrt2M)/(d^(3))`