Lesson 1

Coils, Coils, Coils!
Wrap a wire around practically anything and you’ve got a coil!

4 You have played with permanent magnets and you may have made
temporary magnets
but have you every made an electromagnet
5 To do this you will need: battery band magnet wire 1.5V battery nail You can make a magnet
with electricity.
sandpaper
6 Wrap the rubber band around the battery. Wrap the wire around
the bolt or nail,
at least 30 times.

The wound
wire
is called
a COIL.
Leave plenty of
wire at each end.
Sand each end
of the wire
with sandpaper.
1 Making an Electromagnet 2 3
7 LESS! Connect each end of the wire to the battery
by slipping them under the rubber band.
Make a coil with half the turns (15).
Does the electromagnet
pick up more or less paperclips
Count and record
the number of
paperclips
you can pick up
with the nail.
Electromagnet! 4 5
8 Congratulations! You just made a magnet
with electricity!
9 Which end of the compass needle points to the head of the nail? Does an electromagnet have a north and south pole? NOW flip the wire connections
to the battery.

What happens to the poles
of the electromagnet.
1 2 Test it with your compass. Which end of the compass needle points to the tip of the nail?
10 Test these for yourself.

1.5V

1.5V

1.5V

3V
11 You can weaken a temporary magnet by hitting it against a table or dropping it on the floor.

You can turn off your electromagnet by pulling one of the wires
away from the battery.
ON OFF Sometimes the nail
stays magnetized.
Can you guess why?
Turning Electromagnets On and Off
12 Electromagnets are used to sort scrap metal.
Electromagnets can lift huge loads of iron and steel.
14 Detecting Magnetism in a Wire You will need: Place the wire
over the
compass.
What happens to the compass needle
for each arrangement of the wire?
Briefly touch the other
end of the wire to the other battery terminal.
Hold one end
of the bare
wire firmly against
one terminal
of the battery.
wire compass 1 2 3 4 EXTRA: Place the wire next
to the compass and repeat 2-3.
Then try wrapping the wire
around the compass, as show.
15 Electromagnetism How Does Electricity Create A Magnet? 16 Magnetic Field Around a Wire Click on
Electra
below.
Electrons, flowing in a wire, create a magnetic field around that wire.
Use the hand (compass) to observe the direction of this magnetic field around the wire.
Now click on the "current direction switching" rectangle to flip the current.
What happens to the direction of the magnetic field around the wire?
Click on the box at the bottom to demonstrate the right-hand rule for both directions.
Click on circles 1A, 2A or 3A, to add in one, two or three batteries in series.
17 When electrons flow
in a wire, what happens around the wire
What instrument can you use to detect a magnetic field around a wire What did you use
to make a magnet
you could turn ON and OFF
As you increase
the number of turns
in a coil, what happens
to the electromagnet
1 2 3 4 a magnetic field forms around the wire a compass a battery, a wire and a nail it gets stronger
18