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Bellwork:
• What are magnets? Do you think magnets attract all kinds of
metals? If so, what kind of metals do you think they attract? If
not, why do you think that is? Use the sentecnce frames to
complete your bell work and be prepared to share 
• Magnets are __________________.
• I think magnets attract all metals such
as:____________________.
or
• I do not think they attract all metals because
____________________.
Next Generation Science Standard(s)
MS-PS2-3. Ask questions about data to
determine the factors that affect the
strength of electric and magnetic
forces.
Objectives:
Content Objective “What you
will be learning”
• Identify some properties
of magnets.
• Identify the causes of
magnetism.
• Identify types of magnets.
• Build an electromagnet
that produces a magnetic
field from an electric
current.
Language Objective “How you
will be learning”
• Define magnets, magnetic
force, magnetic poles, and
magnetic field in your
science dictionary.
• Complete a quick lab on
electromagnet and answer
each question using
complete sentences.
Vocabulary this should go into your
personalized science dictionary
• Magnet: any material that attracts iron or objects
made of iron.
• Magnetic force: when you bring two magnets
together, they exert a push or a pull on each
other.
• Magnetic poles: two magnets can push each
other apart because of their ends.
• Magnetic field: the area surrounding a magnet
where magnetic forces can be detected.
Magnetism and
Electricity
8th grade lesson
Part I: Magnets
8th grade lesson
Attention getter!
JUKE!
Attention getter!
•Each group will be given a magnet and an
iron nail.
•Take the nail and try and attract the
paper clip, did anything happen?
•Now take the other end of the nail (not
the sharp part) and rub it at least 50 times
to the magnet. Now touch the paper clip,
what happens?
What is Magnetism?
•Magnetism is a force created by magnets.
•Magnetism is also called magnetic force.
•Only magnets produce magnetic force.
•Magnetic force is invisible and can be felt by
objects around or near a magnet.
•Magnetic force attracts or repels other
objects or magnets.
Magnets
•A magnet is an object that produces magnetic
force.
•The strength of a magnet’s magnetic force
depends on the size of the magnet and the
material the magnet is made of.
•Most magnets are made from iron, nickel, or
cobalt.
•Not all iron, nickel, or cobalt objects produce
magnetic force.
Magnets
Color the pictures. Cut
out the magnet. Then
cut out the objects.
Glue the objects that
are magnetic on the
magnet. Glue the
objects that are not
magnetic below the
magnet.
Magnets
•Magnets have ends called poles. One pole
is called the north pole (N). The other is
called a south pole (S).
•The north pole is attracted to the south
pole.
•The north pole repels when another north
pole is close by, same goes for the south
pole.
Magnets
Magnets
On each part,
identify whether
the magnets attract
or repel each other.
Write it below the
picture of the
magnets.
Magnets
Magnets
•You cannot separate the north and south
pole of a magnet.
•When you cut a magnet in half, you get
two smaller magnets.
Magnets
•All matter is made of atoms.
•Atoms have a magnetic fields. Atoms
group together when their magnetic fields
align. These groups are called domains.
Magnets
•In a magnet, domains point to the same
direction. Many little magnets form a
large magnet.
•In a non-magnet, the domains point in
random directions.
Magnets
Magnets
Types of Magnets
•There are three types of magnets:
Types of Magnets
Types of
Magnets
Magnetic Materials
•Objects that are attracted or repelled by
magnets are called magnetic materials.
•Most magnetic materials are made of iron,
nickel or cobalt.
•Some alloys (mixtures of metals) are
magnetic as well. For example, steel is a
magnetic alloy made of iron and carbon.
•Lodestone (magnetite) is a magnetic rock
commonly found inside earth.
Lab 1: Building and
Electromagnet
• Each person in the group must take on a role.
• Facilitator: in charge of ensuring everyone is on task.
• Time keeper: keep track of time.
• Materials monitor: in charge of prepping materials and putting back
materials.
• Questions commander: only this person can see me for group or
individual questions.
• Recorder: jots down important notes during lab (data, answers, etc.)
• Your job is to read the lab sheet first before starting on the
creation of your electromagnet.
• During the lab, please take into consideration the lab rules: NO
HORSEPLAYING or PRACTICAL JOKES.
• Please be careful, sometimes the wire and battery can create heat
which will burn your fingers.
Magnetic Materials
•Using a blank
sheet of paper,
create
something
similar like
this and paste
it into your
notebook. Be
creative. Title
Magnetic Materials
•Cut the
pictures out
and its
descriptions
and paste it
inside the
magnet
template you
Magnetic Materials
•Your end
product/resul
t should look
like this.
Magnetization
•If you run a magnet over a magnetic
object, you can convert that object into a
temporary magnet. This conversion is
called magnetization.
•You must run the magnet in the same
direction over that object a few times.
This causes the object’s domains to align
which makes a magnet.
•Only magnetic objects can be magnetized.
Demagnetization
•Demagnetization is the loss of a magnet’s
magnetic force.
•Heating, hammering or dropping a
magnet can cause demagnetization.
•Temporary magnets are easy to
demagnetize.
•Permanent magnets are more difficult to
Magnetization vs.
Demagnetization
Magnetization vs.
Demagnetization
Magnetic Field
•Magnetic objects are influenced by a
magnet if in the magnet’s magnetic field.
•The strength of the magnetic field
weakens as you move away from the
magnet.
•Stronger magnets have larger and more
powerful magnetic fields.
Magnetic Field
Magnetic Field
Magnetic Field Lines
•The magnetic field begins at the magnet’s
north pole. It travels outward and around
a magnet to the south pole and then
through the magnet from south pole to
the north pole.
•Magnetic field lines never cross.
Magnetic Field Lines
•A magnetic field is invisible.
However, you can visualize a
magnet’s magnetic field with iron
filings.
Magnetic Field Lines
Magnetic Field Lines
Magnetic Field Lines
• Cut out the two magnets.
• Draw lines through and around the
magnet to show the magnetic field.
• Describe what happens to the
strength of the magnetic fields as you
go further away from the magnets.
• “As the magnets move further
away from each other, the
__________________.
• Remember where does the line begin
and where does it extend outwards to
and where does it go through…
Magnetic Field Lines
This is
what your
magnetic
force
(arrows)
should
Magnetic Field Lines
• Describe what
happens to the
strength of the
magnetic fields as
you go further away
from the magnets.
• “As the magnets
move further
away from each
other, the
magnetic fields
Magnetic Field
Lines
Earth’s Magnetic Field
•The Earth is made of many layers. The
Earth’s core is made of iron.
•The outer core is made of molten, flowing
iron.
•The inner core is made of solid iron.
Earth’s Magnetic Field
•Earth’s iron core acts like a giant bar
magnet. It creates a magnetic field around
earth.
•Earth’s magnetic field extends outward
around Earth and down towards the core
of Earth at the poles.
Earth’s Magnetosphere
•Earth’s magnetic forms a protective shield
around Earth. This shield is called the
magnetosphere.
•The magnetosphere extends 37,000 miles
out into space.
Earth’s Magnetosphere
•The magnetosphere protects us from solar
wind. Solar wind is dangerous steam of
charged particles thrown out from the
sun. These particles deflect off Earth’s
magnetosphere.
Earth’s Magnetic Poles
•Earth’s iron core also
creates magnetic poles on
Earth.
•Earth’s magnetic poles
are not the same as
Earth’s geographic poles.
•The magnetic poles are
located about 965 km or
o
10 from Earth’s
Earth’s Magnetic Poles
•The north pole of a
compass needle points
toward the North
geographic pole.
•Remember that the North
pole of one magnet is
attracted to the South pole
of a second magnet.
•If the North pole of the
compass needle points
North, technically Earth’s
Earth’s Magnetic Pole
Earth’s Magnetic Pole
Earth’s Magnetic Pole
Earth’s Magnetic Pole
Earth’s Magnetic Pole
Earth’s Magnetic Pole
Earth’s Magnetic
Pole
Make a magnetic compass
•In your groups you will create your
magnetic compass using the materials
given.
•Read the lab sheet and procedures before
doing anything.
•Once you’ve gone through everything,
follow the procedures to set up your
materials and begin.
So, did we…
• identify some properties of magnets?
• identify the causes of magnetism?
• identify types of magnets?
• build an electromagnetic that produces a magnetic field
from an electric current?
• define magnets, magnetic force, magnetic poles,
and magnetic field in your science dictionary?
• complete a quick lab on electromagnetic and
answer each question using complete sentences?
Part II: Electric Force…to
be continued at a later
time 