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Electromagnet Lesson
Plan Amount of time Demo takes: 5-10 mins.
Try this at home!
Materials
● Steel Nail
● Wire (16-30 gauge)
● Battery (D-Cell)
● Tape
● Wire Strippers
● Alligator Clip Jumper (4)
● Paperclips
Set-up Instructions
1. The nails that are wrapped will be labeled with the amount of times the
nail is wrapped. The less wraps the weaker the electromagnet will be when
it is being used.
2. Place nails and paperclips on the table in piles and evenly spread out the
coiled nails and wire.
3. Keep the batteries and jumpers on your side of the table.
SAFETY!
● Be careful with smaller gauge wire; it will have a tendency to get warm.
Lesson’s Big Idea
● An electromagnet is a spool of wire the when an electrical current is passed
through the wire and attract magnetic objects.
Background Information
● Right Hand Rule- Electricity and magnetism are forms of the same force.
As a result when electric current runs through a wire it creates a magnetic
field that wraps around the wire. If you place your thumb of your right hand
in the direction of the current and curl fingers inward this curl is in the same
direction of the magnetic field. As a result when the wire is wrapped it
causes the magnetic field to be to be in the same direction through the
core of the spool of wire.
1/3 ● Magnetic core-In this demo we use iron as a core this is to amplify the
field created by the spool of wire. Iron is a magnetic material because it has
slightly polar atoms. When you apply a magnetic field to the iron, it will
orientate all of the atoms in the same direction, amplifying the field and
creating a magnet.
Instructional Procedure
1. The pre-wrapped nails can be hooked up to the battery with the jumpers.
The ones with less wraps will only be able to pick up small objects like the
paperclips, while ones with more wraps will be able to pick up nails.
2. Attach the jumpers to the ends of the wire and hold the other ends of the
jumpers to the battery. Have the participants move around the nail, to
show them the properties of an electromagnet.
3. The nails that are unwrapped with the lengths of precut wire are for the
participants to wrap.
4. Once the participant wraps the nail you can tape the wire so that it will not
come uncoiled.
5. Attach a jumper to one end of the exposed wire and then attach another
jumper to the other end.
6. Touch the opposite ends of the jumpers to each end of the battery so
there is a flow of electricity through the coil of wire around the nail.
7. Have the participant then move the nail near the paperclips and other nails
to show that it attracts them.
8. You can then remove one alligator clip so that the paperclips/nail can fall or
are no longer attracted to the nail.
Assessment/Sample questions you can ask
● Do you think that the nail will attract another nail?
● How strong do you think the electromagnet will be?
● What will the electromagnet attract if anything?
● Why do you think this works with nails but not something like a pencil?
Clean Up
● For cleanup return everything to the bin and throw away tape used and
make sure the Labeled coils are still intact.
● Coil up the free wire so that it is not all in a heap in the bin.
References
2/3 ● Wiki on electromagnets http://en.wikipedia.org/wiki/Electromagnet
● Electormagnetic force http://www.youtube.com/watch?v=1TKSfAkWWN0
● How iron magnets work
http://www.youtube.com/watch?v=hFAOXdXZ5TM
Next Generation Science Standards
● K-5
○ 3-PS2-3/4
● 6-8
○ MS-PS2-3/5
● 9-12
○ HS-PS2-5
3/3