The Magnetism Unit:

1
The Magnetism Unit I Hope You Will Be
Attracted To It
2
Magnetism - The force that a magnet has upon
magnetic materials. Name some items that use
magnet in order to operate properly.
Speakers
Electric Motors
Computers
Telephones
Television
VHS and Audio Tapes
3
The Earth is a very large magnet. Like any
magnet, it has a north pole and a south pole.
s
n
4
Molten metals churning in the Earths core create
a magnetic field around the entire planet.
S
N
The lines of force come out of the Magnetic South
Pole, extend into outer space, and plunge back in
at the Magnetic North Pole.
5
A compass needle is magnetic and floats freely to
align with Earths magnetic field.
6
Aurora Borealis (Northern Lights) Solar particles
entering the Earths atmosphere at the Magnetic
North Pole excite our atmospheric gases to create
glowing plasma.
7

All magnetic materials are made up of groups of
atoms called domains. The domains must line up
in order for that metal to become a magnet.
Magnetized domains
Not magnetized
8
Three naturally occurring magnetic metals
Iron Nickel Cobalt
9
All magnets have an area of force around them
called a magnetic field. The lines of force in
a magnetic field come out of the north pole and
go into the south pole.
N
N
S
S
10
In Magnetism, Opposite
Poles Attract
N
S
N
S
11
N
N
While Like Poles Repel
12
Electromagnets
An electromagnet is created when electric current
is passed through a wire that is wrapped around
an iron core. A strong magnetic field is created
as the electricity flows through the wire.
13
MRI - Magnetic Resonance Imaging
14
MRI - Caution must be taken