Physics – 4.1 Simple phenomena of magnetism | e-Consult

The bar magnet produces a magnetic field around it. The direction of this magnetic field at any point is the direction of the force that would be experienced by the North pole of a small, temporary bar magnet placed at that point. The compass needle is a small, temporary bar magnet. Therefore, the compass needle aligns itself with the direction of the magnetic field at its location. Since the compass needle points towards the North pole of the bar magnet, the magnetic field lines are directed from the South pole of the bar magnet, through the paper, and towards the North pole. This means the force on the North pole of the compass needle is in the direction of the magnetic field, hence the compass needle points towards the North pole of the magnet.