Attraction and repulsion between magnets

Let Us Recapitulate

1.    Natural magnet: Magnetite is called natural magnet.    
2.  Uses of a magnet: A magnet finds its use at a number of places. For example, refrigerator's door, some pencil boxes, many toys, magnetic stickers, soap stand, pin stand, all make use of a magnet for their functioning.
3.  Shapes of magnets: Magnets are made of different materials and in different shapes.
4.  Effect of a magnet on materials: A magnet attracts certain materials, whereas some do not get 
attracted towards magnet.
5. Magnetic materials: The materials which get attracted towards the magnet are known as magnetic materials, e.g., iron, nickel, cobalt.
6. Non-magnetic materials: The materials which are not attracted towards the magnet are known as non-magnetic materials, e.g., leather, plastic, cloth, paper.
7. Magnetic poles: Magnetic attraction is maximum near the ends of the magnet. These ends are called magnetic poles.
8.     When suspended freely, magnet always aligns in north-south (N-S) direction.
9.  Lode stone: It was a stone used by sailors in olden days to identify directions when they were in sea.
10. Compass: This is a small glass case containing a magnetised needle pivoted on a nail. The needle can rotate freely. Wherever it is kept, its needle always rests in north-south direction. Normally the 
north-pole of the needle is painted red or some other indication is given to identify north and south-poles. So using this needle, north and south can be identified.
11. Attraction between two poles: Opposite poles of two magnets attract each other. It is called 
attraction.
12. Repulsion between two poles: Similar poles of two magnets repel each other. It is called repulsion.
13.Magnetic effect can pass through screen: Magnetic influence can pass through screens of some substances like cloth, plastic, paper, glass, etc.
14.  Magnets lose their properties if they are heated, hammered or dropped strongly and hardly.
15.  To keep them safe, bar 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.
16.    Soft iron is used to make electromagnets.

Key Words

1.  Compass: This is a small glass case containing a magnetised needle pivoted on a nail. The needle can rotate freely and always rest in north-south direction.
2. Magnet: A magnet is a metallic object which attracts iron or magnetic things.
3.  Magnetite: It is an ore of iron which has magnetic properties.
4. North pole: When suspended freely, one pole of the magnet always points towards north. This is known as north-pole.
5. South pole: When suspended freely, the end of a magnet which points towards south. This is known as south-pole.