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Q & A: Energy from magnets?

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Most recent answer: 08/05/2012
Q:
Magnets provide a constant force either on feris metals or other magnets, So why can't this be used to create energy? like a Magnetic motor? I know conventional motors use magnets to to create energy, but it requires electricity to run them,a "magnetic" motor wouldn't require any input.
- jacob (age 16)
vancouver wa usa
A:
Magnets don't violate the law that energy is conserved any more than anything else does.

Let's look at something similar. The earth provides a constant force (gravity) on everything near it. Does that mean we could extract energy forever from the earth;s gravity? No- if something happens to be uphill, we can extract energy as it falls, because the gravitational potential energy is reduced. Once it's down , though, that's it. It's exactly the same principle with electrical and magnetic forces.

Mike W.

(published on 08/05/2012)

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