Class 6 Science Fun with Magnets -

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Magnets

A Magnet is a material or objects that has a property of attraction or pull force for ferromagnetic materials like iron, cobalt, nickel etc.

Magnets attract Ferromagnetic materials like Iron towards it.
Magnets also attract and repel other magnets.
Applications of attraction property of magnets in day to day life are – Refrigerator doors, pencil boxes or purses with magnetic closure buttons, iron separator from waste etc.

Magnets – Discovery, Types & Poles

There are two types of magnets:

Natural Magnets are made up of magnetite and are found in nature.
Artificial magnets are prepared using various processes and with the help of iron.Examples of artificial magnets include bar, horse shoe, cylindrical, ball-end magnet etc.

A magnet has most magnetism at the two ends of it. These ends are called Poles.

As a convention, these ends are usually referred to as South (S)and North (N)
In a freely suspended magnet, the end of the magnet that points towards North is called its North seeking end or North Pole.The other end of the magnet that points towards South is called its South seeking end or South Pole.

Magnetic and Non-Magnetic Materials

Materials which get attracted towards magnet are called Magnetic materials. Examples are iron, nickel, cobalt.
Materials which do not get attracted towards magnet are called Non-Magnetic materials. Examples are paper, wood, plastic etc.

Finding directions using Magnet

A freely suspended magnet always comes to rest in North-South direction. This property has been used from olden days to find directions.
Compass is a device used to find directions.
Compass consists of a magnetized needle and a dial, marked with directions, inside a box with glass cover. The freely rotating needle comes to rest in north-south direction as depicted on the dial. The north pole of the needle is marked red for distinguishing it from south pole.

Making own Magnet

Take an Iron bar and a Magnet bar.
Place one of the magnet’s pole at the edge of the iron bar.
Slide the magnet towards the other edge of the iron bar without lifting the magnet.
Lift the magnet now and place at the initial position again with same pole touching iron bar.
Repeat this process 30-40 times or more till the iron bar becomes magnetized.

Making own Compass

Take a cork, a magnetized needle (using above process) and a bowl of water.
Glue the needle to the cork and set the cork in bowl. Needle should not touch water.
Even after rotating the cork a few times in any direction, the needle will make the cork move so that it points in North-South direction.

Attraction and Repulsion

Magnets attract iron but can attract and repel another magnet.

Like or same poles of two magnets when brought closer, they repel each other. Example, south pole of one magnet repels south pole of other. Similarly, north pole of one magnet repels north pole of the other.
Unlike or different poles of two magnets when brought closer, they attract each other. Example, south pole of one magnet attracts north pole of other.

Precautions with Magnets

Below are a certain conditions where a magnet may get damaged:

Magnets lose magnetism when they are heated, hammered or dropped from some height.
Magnets become weak if they are not stored properly.

Magnets should be stored as mentioned below:

Magnets should be kept in pairs with their unlike poles on the same side. They must be separated by a piece of wood while two pieces of soft iron should be placed across their ends.
For horse-shoe magnet, one should keep a piece of iron across the poles.

Magnets also have adverse effects on equipment. Precautions to be taken are:

Keep magnets away from cassettes, mobiles, television, music system, compact disks (CDs) and the computer.

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