Demagnetization

Demagnetization:

This is a process in which a magnet is made to lose its magnetism. This can be achieved by:

1. Electrical method
2. Mechanical method
3. Heating method

Electrical Method:

This is the best and one of the most efficient ways of demagnetizing a magnet. The magnet is placed in a solenoid and alternating current (a.c) is passed through it. The alternating current rapidly switches directions When the magnet is withdrawn from the solenoid in the east-west direction, the magnet will lose its magnetism.

Placing a demagnetized bar magnet in the east-west direction helps ensure that the molecular magnets within the bar magnet remain randomly arranged.

Mechanical Method:

Hammering, hitting or dropping the magnet on the floor several times while pointing it in the east-west direction, causes the the magnetic particles in the magnet to lose alignment thus its magnetism

Heating Method:

Heating the magnet until it becomes red hot and allowing it to cool in the east-west direction will make the magnet lose its magnetism. This will demagnetise the magnet due to the increased vibrations of the magnetic particles in the magnet, causing them to lose their alignment and magnetism.