WOW !
Magnet Magic
Magnetic materials are
attracted by magnets
Object
Made of ?
Magnetic?
Yes or No?
2
A paperclip is attracted to the
ends of a bar magnet


The paperclip is made of steel.
The arrow shows the force on
the paperclip.
3
Representing forces with arrows

The magnet also is pulled
towards the paperclip.
The two forces are the same size
and in opposite directions.
4
2 magnets

These ends attract

These ends push apart – (repel)
There are two sorts of magnetic poles.
5
Making a compass

When a magnet is hung up
one end will point North.
 so


N
S
it lines up North/South
The same end always
points North
The end that points
North is called the
north seeking pole
6
The
Earth
is a
magnet
7
A compass uses a tiny magnet
which can
swing round.
8
NORTH POLE
The
Earth
is a
magnet
9
Using a compass to find
directions


A compass needle always points to the
Earth’s North Pole.
Some birds use the Earth’s magnetism
to find directions.
10
A magnet
has a
north pole
and a
south pole.
S
N
11
The north pole attracts the
south pole of the other magnet.
S
N
S
S
N S
N
N
12
The north pole repels the north
pole of the other magnet.
S


N
N
S
You can feel the magnets pushing apart.
This is called repulsion
Note - south poles also repel each other
13
Now for
some games!
14
Something very new !
• A computer that will stay booted up
when you switch it off – it will be on
sale in a few year’s time.
• It will have memory called
MRAM and use special
magnets !
(Magnetoresistive Random Access Memory)
15
What have we learned?

Magnets will attract magnetic materials
 iron

and steel
Magnets have two sorts of poles
 north

and south
Magnets repel each other as well as attract
similar poles repel
 opposite poles attract



A compass is a little magnet
The Earth is like a magnet
 compasses

are used to find directions
Special magnets are used in computers
16
Magnets are
used in lots
of ways
17
It moves!


A motor causes
movement.
An electric current
and a magnetic
field can make a
simple motor.
magnet + electric current  movement
18
Spot the motors
Can you think of other examples?
19
Very tiny motors can be made



When the drawer for a CD opens and closes a
tiny motor makes it move
A tiny motor moves the camera lens when the
camera is switched on
Many small toys have motors in them
 robots,

Artificial limbs can use tiny motors to act like
muscles
20
Magnets are amazing !
Magnets + electric currents
make things move !