An Electricity generator
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
Read about the New Zealand Energy
Conservation and Renewable Energy Generation Pilot Project that
Michael is involved with...
Lets sum up what we have done:
Move a wire next to a magnet ====>
electricity comes out
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
VIDEO CLIP: generator.wmv file
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:
- Who was Michael Faraday? What was his relationship
with Sir Humphry Davy?
- 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.
sensors to detect the current and voltage using a digital
- 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
- 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
Selected by the sciLINKS program, a
service of National Science Teachers Association.