MAGNETISM CBSE CLASS 6TH 7TH PROJECT

1. Aryaman Sharma – 6A
Magnetism

2. Long ago, in ancient Greece, there
lived a shepherd named Magnes. He
used to take his herd of sheep to the
nearby mountains for grazing. In the
evening he used a stick to collect his
cattle back home. One day he carried a
iron stick. While he was beating his
stick got stuck on the ground to a
stone. He tried pulling it out and had
to apply force to successfully do so. He
was surprised. He thought there was
some evil spirit in the stick or the rock.
History

3. Any substance which has the ability to attract certain
substances is called Magnet.
The
phenomenon by
which magnets
attract certain
substances is
called
Magnetism.

4. Properties of a Magnet
1. Magnet attracts magnetic substances.
2. A freely suspended magnet always rests in the north-
south direction.
3. The magnetic pull or magnetic influence is stronger near
the ends of the magnet.
4. Poles exists in pairs.
5. Unlike poles attract and like poles repel.

5. Properties of a Magnet

6. Types of Magnets
Natural Magnet
Lodestone was the magnet found occurring naturally in the
earth’s crust. Lodestone means ‘leading stone’. It helped
people find their way on land and sea.
Artificial Magnet
Artificial magnets are those magnets which have been
imparted the properties of the magnet by artificial means.

7. Magnetic Field
There is a magnetic field in the area around a magnet. The magnet
exerts its influence or the force within the area. Any magnetic
object kept within the area will experience a pull towards the
magnet.

8. Magnets formed due to electric current are called
electromagnets.
Temporary magnets lose their magnetism as soon as the cause
producing it is removed. Electromagnets are temporary magnets.
Permanent magnets are those that retain their magnetised for a
long time.
Temporary and Permanent Magnets

9. Uses of Magnets
1. You can use a magnet to find a pin/needle dropped on the
floor.
2. Magnets are used in making magnetic stickers and toys.
3. Magnets are used by doctors to pull out small iron
particles from the wounds of the victims of accidents.
4. Magnet in a magnetic compass can help find the
directions.
5. Electromagnets are used in the door bells, electric motors,
televisions sets, computers, speakers, ATM cards etc.
6. Electromagnets are used to lift heavy loads in warehouse.

10. Compass
A magnetic compass is a device used to determine the direction.
It is essentially made up of a magnetic needle which is free to
swing about a pivot at its centre. The needle always come to rest
pointing towards the earth's north-south direction.

11. The process by which a magnet loses its properties is called
demagnetisation.
Magnets can lose their strength
•If hammered or dropped.
•If heated.
•If not stored properly.
Demagnetisation

12. Storing Magnets
To preserve magnetised for a long time, magnets are stored in
magnetic keepers.
Magnetic keepers are made of simple pieces of soft iron.
They are kept in contact with the opposite pole of a pair of bar
magnets or across the poles of a horseshoe magnet. They help to
preserve the magnetic lines of force.