Magnetism, Magnet properties, types and uses

Magnetism is the ability of the magnet to attract magnetic materials, 2000 years ago, the ancient Greeks found a type of black rock located in an area named Magnesia, This type of rock has an attraction force to any material made of iron, So, scientists called this black rock ” natural magnet ” and its attraction force ” magnetism “.

Types of magnet

Magnets are classified into two types which are natural magnet and artificial magnet, Natural magnet is a black rock, It is one of the iron ores which is known as Magnetite.

An artificial magnet is a magnet made by man, It has different shapes and sizes, Shapes of artificial magnets are horse-shoe magnets, ring magnets, needle magnets, and bar magnets.

But, the magnet attracts some materials and does not attract others, So, the materials are divided into two types according to the ability to be attracted, which are magnetic materials and non-magnetic materials.

Types of magnet

Magnetic materials are the materials that are attracted to the magnet, such as iron, nickel, steel, and cobalt, Non-magnetic materials are the materials that are not attracted to the magnet, such as chalk, glass, paper, aluminum, copper, wood, leather, and plastic.

The magnet attracts metallic paper clips but does not attract copper wire, because paper clips are magnetic materials, but copper wire is a non-magnetic material, The magnet is used in making the doors of refrigerators and the small toys sticking on them.

Properties of magnet

1. The magnet has two poles.
2. Freely suspended (moving) magnet always takes a fixed direction, which is a north-south direction.
3. The like (similar) magnetic poles repel each other, but the dislike (opposite) magnetic poles attract each other.
4. The magnet is surrounded by an area called the magnetic field.

The regions of the magnet that have the most attraction force are the two ends which are called the two poles of a magnet, To differentiate between the two poles of the magnet, the north pole is often red-colored, but the south pole is often blue-colored.

Two poles of a magnet (magnetic poles) are the areas (regions) of the magnet that have the most powerful force of attraction or the areas of the magnet where most of the attraction force (magnetism) is concentrated.

When you approach a magnet to some iron nails, most of them are attracted to the two poles of the magnet, because the attraction force of the magnet is concentrated at the two poles of the magnet.

One pole of the magnet tries to search for the north direction of the Earth, while the other pole tries to search for the south direction of the Earth, Freely suspended (moving) magnet always takes a fixed direction, which is north-south direction.

The pole of the magnet which points to the north direction is called the north pole (N), but the pole of the magnet which points to the south direction is called the south pole (S).

The similar (like) magnetic poles repel each other, but the opposite (dislike) magnetic poles attract each other, The north pole of a magnet attracts the south pole of another magnet but repels the north pole, because the opposite magnetic poles attract each other, while the similar magnetic poles repel each other.

The magnetic field is the space around the magnet in which the effect of the magnetic force appears, The magnetic force is the ability of the magnet to attract the magnetic materials existing in its field.

The magnetic force is an invisible force, so, we use the iron filings to see the magnetic field that is formed by the effect of magnetic force, The magnetic field around the magnet takes a regular shape, and the greatest magnetic force of the magnet is concentrated at the two poles of magnet.

Uses of magnet

Making the magnetic compass is one of the uses of magnets in our daily life, The compass is a needle magnet that takes a fixed direction which is north-south direction.

Magnetic compass

A long time ago, the Chinese used the magnetic rock that spins freely taking a fixed direction which is a north-south direction, A Chinese major general depends on this idea in leading his army through dense foggy areas.

In 1600, the English scientist William Gilbert took the idea of magnetic rock and made a small magnetized needle that is light for spinning freely, This magnetized needle was the basic idea in making the compass.

The compass structure consists of a light and small magnet (magnetic needle) that can spin freely around a fixed axis, where the north pole of this magnetic needle refers to the north direction of the Earth and its south pole refers to the south direction of the Earth, The compass is used to locate (identify) the main four geographical directions, because its magnetic needle always points to the north and south directions.

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