Explain with the help of a diagram how the intensity and direction of the magnetic field of a bar magnet can be determined.
Answers
The lines of magnetic field from a bar magnet form closed lines. By convention, the field direction is taken to be outward from the North pole and in to the South pole of the magnet.
As can be visualized with the magnetic field lines, the magnetic field is strongest inside the magnetic material. The strongest external magnetic fields are near the poles. A magnetic north pole will attract the south pole of another magnet, and repel a north pole.
The magnetic field lines of a bar magnet can be traced out with the use of a compass. The needle of a compass is itself a permanent magnet and the north indicator of the compass is a magnetic north pole. The north pole of a magnet will tend to line up with the magnetic field, so a suspended compas needle will rotate until it lines up with the magnetic field.
To find the direction of the magnetic field around a bar magnet, place a magnetic compass with its South-Pole near one of the poles of the bar magnet. Locate and the point where the North-pole of the needle points. Now, lift the needle and place its South-Pole on the marked point. Now, again see where it North-Pole points. Repeat this process and you will get the direction of the magnetic field as shown below.
