Magnetic field around magnet
The space where the magnetic force of the magnet acts is called a ‘magnetic field.’ The direction of the magnetic field is determined in the direction indicated by the N pole of the magnetic needle placed at that point.
The magnetic field is invisible to the eye, but you can check the magnetic field by looking at the iron powder’s arrangement when you sprinkle it around a magnet. The magnetic field expressed as a line is called a ‘magnetic force line.’
When the magnetic field is strong, the magnetic force lines appear dense, and where the magnetic field is weak, the magnetic force lines appear sparse. In a bar magnet, the closer it is to the magnet’s N and S poles, the denser the magnetic force line. It can be seen that the magnetic field gets stronger as it approaches the pole of the magnet and more weakens as it moves away from the pole of the magnet.