Magnet and its Properties

When electric current passes through current carrying conductor or coil then a magnetic field is produced around it. The working of appliances like electric bell is based on this principle. As opposite to this if a continuous change in magnetic field is produced then electric current can be produced. This is how electricity and magnetism have become synonymous today.

Magnet

According to history, the use of magnets were discovered by the ancient Greeks during the period of Greek Civilization. They found stones which were able to attract iron and nickel like other substances. This naturally occurring stones which was discovered then is called as lodestone. This is an oxide of iron (Fe3O4).

The property of attraction of small particles of iron towards lodestone is called as magnetism. The magnetic force of attraction of these natural magnets is much less and thus, these magnets cannot be used for practical purposes. Strong magnets made of iron, nickel and lead are made artificially and used for practical purposes. Those magnets are also called as permanent magnet.

A magnet is a material or object that produces a magnetic field which is responsible for a force that pulls or attracts on other materials. These strong magnets can be made in various shapes and creates its own persistent magnetic field. The magnets that are commonly available in different shapes are:

  • Bar magnet
  • Horseshoe magnet
  • Cylindrical magnet
  • Circular magnet
  • Rectangular magnet

These magnets of different shapes are used in various appliances used at home like tape recorder, radio, motor, door-bell, head phones. These magnets are used in various appliances to either hold or separate, control, elevate (lift) substances, changing electrical energy to mechanical energy (motors, loudspeakers) or mechanical to electrical energy (generators and microphones).

If a natural magnet is suspended freely with the help of a string, it always rests in the north-south direction. If the magnet is slightly turned from this direction, it still returns to the same. The end that rests towards the north is named as North Pole while the one which ends at south is named as South Pole. They are represented as N and S.

Properties of Magnets

  1. Attracts iron towards itself.
  2. Freely suspended magnet always rests at the north-south direction.
  3. Like poles repel while unlike poles attract.
  4. If iron pieces are brought near a strong magnet they also start behaving as magnets.
  5. The poles of a magnet cannot be separated.