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Expert: Dan Fink - 11/4/2009


Question
QUESTION: Dan,

One last thing. Could one magnet not push another one because of polarities. If i had one magnet in a stable position and another that could be spun, could the opposite polarities not force the spinning magnet around and thus propel a small generator?

How could this fail?

Thanks again

Josh

ANSWER: Hi Josh --

Nope. The magnet will move only as long as you push it. No system can be more than 100% efficient -- there are always losses. In this case you lose energy from friction, flux leakage between magnets, and from the Earth's magnetic field.

Sounds like you need to get a few nice strong magnets and try some experiments! You'll greatly enjoy it, magnets are fun!

DAN



---------- FOLLOW-UP ----------

QUESTION: Can I ask where I would get some strong magnets?

Thanks for all your help and clarification

Josh

Answer
Hi Josh --

You want to get "rare-earth" magnets; the most common and inexpensive formula is Neodymium-Iron-Boron. This is often shortened to "NdFeB". If you punch:
NdFeB magnet
into Google, you'll find lots of places online that sell these magnets. Every so often , I have seen them at Home Depot and Ace Hardware, but not always. Most are sold online.

DAN

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Dan Fink

Expertise

Though my experience is mostly in the fields of electricity, magnetism, and physics, I have a broad science background. My career is in the field of alternative power sources -- solar, wind, water and battery power. But any questions about electricity, magnetism, energy conservation, power generation, electric motors, and even general physics are very welcome--especially from kids. They ask the best questions of all! I pride myself in answering science questions accurately, with ideas for SAFE, easy experiments that kids can perform by themselves--and that let them prove the answers to their own satisfaction. I think science should be fun, and available to everyone, regardless of age.

Experience

I have volunteered in our local public schools for 5 years. I currently make presentations at our schools about electricity and magnetism, with a focus on solar, wind, water and other alternative power sources. I try to demonstrate at our schools how easy it is to make electricity, with simple devices using spinning magnets and coils of wire--powered by wind, water, bicycles, gerbils...etc. And of course solar panels! I am the webmaster of Otherpower.com, an alternative energy website. I have lived 10 miles from the nearest power pole for 11 years--I make all my own electricity from scratch with sun, wind and water.

Publications
Otherpower.com
Wondermagnet.com
Co author of the book "Homebrew Wind Power" ISBN 978-0-9819201-0-8
My articles appear regularly in such magazines as Home Power and Back Home
Education/Credentials
BA Technical Journalism


Education/Credentials
BA Technical Journalism

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