Magnets
Making a temporary magnet
Using electricity
The electromagnet can now attract magnetic materials/objects. Only if it is connected to a source of electricity. When it is removed from the the source of electricity it no longer becomes an electromagnet.
Coil a long piece of wire around
an iron nail at least twenty times.
Then connect both ends of the
wire to a battery.
Stroking
The magnetised magnet is able
to attract magnetic materials.
However it can only keep its
magnetism for a short period of time.
An iron nail can also be made into
a magnet by stroking it several
times with a strong magnet along
its entire length in the same direction.
Induction
The nail is said to be magnetised
by induction.The magnetised nail
is now able to pick up some metal
clips.As soon as the strong magnet
is removed, the nail loses its
magnetism.
When an iron nail is in contact
with a strong magnet, it
becomes a magnet.
Freely suspended
A freely suspended magnet always comes
to rest in a north-south position.
Non-magnetic materials
-Wood
-Glass...
Magnetic materials
-Iron
-Steel
-Nickel
-Cobalt
-Magnets
Types of magnets
Button magnet
Ring magnet
Rod magnet
Horseshoe magnet
U-shaped magnet
Bar magnet
Characteristics of
a magnet
Objects that are not attracted
to magnets are made of
non-magnetic materials.
Objects that are attracted
to magnets are made of
magnetic materials.
Are used in
Everyday objects such as
-Doorstoppers
-Compasses
-Refrigerators
-Magnetic game boards
Poles
Like poles
Repel
The south pole of a magnet
will repel the south pole of
another magnet.
Unlike poles
Attract
The north pole of a magnet
will attract the south pole of
another magnet.
Has two poles
The south pole and the north pole.
The pull of a magnet is the strongest at the two poles.
The pull of the magnet
can pass through some
materials.
Such as
(non-magnetic materials)
Wood, glass, copper, aluminium...
Can be made from
Lodestones
A lodestone or a natural magnet
is a piece of magnetic ore.
Artificial
Artificial magnets are made
of iron, steel, nickel or cobalt.
