A short bar magnet with its north pole facing geographic north forms a neutral point at P in the horizontal plane. If the magnet is rotated by 90o in the horizontal plane, the net magnetic induction at P is (Horizontal component of earth's magnetic field = BH)

Initially, Neutral point is obtained on equatorial line and at neutral point BH=Bewhere BH= Horizontai component of earth's magnetic field, Be= Magnetic field due to bar magnet on its equatorial line Finally, Point P comes on axial line of the magnet and at P, Net magnetic field B=Ba2+BH2=2Be2+BH2=2BH2+B2H=5BH