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Old Sep 15, 2012, 06:26 AM
richard hanson is offline
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United States, UT, Salt Lake City
Joined Oct 2007
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Quote:
Originally Posted by ciurpita View Post
as my high school chemistry teacher described it, you can push and pull all day on the lab bench bolted to the floor and do no work because it hasn't moved, even though you are exhausted.

a magnetic field, drawing current from the power grid is doing no work even though it is holding something to the ceiling.
how is the force of a magnetic field generated from electricity -- how is lift generated from the movement of a wing through air ?

greg
Pressure differences .
My std answer and I 'm sticking to it
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