An Electricity generator
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Yep, that's about all there
is to making an electrical generator... whenever
you move a conductor such as wire through a
magnetic field, a voltage is induced at its
ends. In fact an airplane flying through the
magnetic field of the Earth has a voltage (or
a potential difference) generated across
its wings by the same principle.
Back to our wire example...you would soon get
tired of waving the wire about. Why not let
the wind or water do the work for you?
If you wind up the wire into a circle to make
a coil you could then balance it on some metal
legs and let the wind move the coil for you.
You have made a wind turbine to generate electricity!
If you let water fall and spin the coil you
have discovered hydro electricity.
Read about the New
Zealand Energy Conservation and Renewable Energy
Generation Pilot Project that Michael
is involved with...
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Lets sum up what we have done:
GENERATOR:
Move a wire next to a magnet ====> electricity
comes out

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Motor from a tape recorder
attached to an old power meter.
If the motor is turned by
hand, the meter needle jumps into
the red showing that electricity is being
produced. This unit can be converted into
a hydro turbine or wind turbine and recharge
a NiCad battery or lead acid battery.
Unit built by Vaughan Hale
1999
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VIDEO CLIP: generator.wmv
file
MOTOR:
What if we reverse the idea of how a generator works?
electricity goes in ====> wire moves when
next to a magnet
We have just invented a simple motor!

FIND OUT MORE:-
Try building the models shown and find out the
answers to these questions:
- What happens to the direction the coil spins
when you connect the battery the other way around?
- What effect does changing the coil have? Try
changing the number of turns of wire, the diameter
of the coil, and the thickness of the wire.
- How is your generator similar to the turbines
used at a hydro power station?
- How are other generators made differently?
- How are other electric motors made differently?
Try this special musical
motor...
- What is electromagnetic induction?
- Read about the New
Zealand Energy Conservation and Renewable Energy
Generation Pilot Project that Michael is
involved with.
- There are other ways to generate electricity.
FInd out how to tap into fruits
and vegetables here...
- Use an salt dough cell to power your own toys
and cyberpets
- Some electrochemical cells can be used again and
recharged. Try to make your own rechargable
battery...

Selected by the sciLINKS program,
a service of National Science Teachers Association.