Two short bar magnets each of magnetic moment of 9 Am ^2 are placed such that one is at x=-3 ~cm and the other at y=-3 ~cm . If their magnetic moments are directed along positive and negative X -directions respectively, then the resultant magnetic field at the origin is

Step-by-step solution

At origin, both magnetic fields will be in same direction. Magnetic field due to M₁ (axial point) aligned & B₁= ₀ 4 2 M r^3 =10⁻⁷ 2 9 27 10⁻⁶ & B₁= 2 3 10⁻¹ ~T aligned Magnetic field due to M₂ (equatorial point) B₂= ₀ 4 M r^3 =10⁻⁷ 9 27 10⁻⁶ = 1 3 10⁻¹ ~T As both B₁ and B₂ points in same direction, so effective field, B= ( 1 3 + 2 3 ) 10⁻¹ ~T B=10⁻¹ ~T =0.1 ~T