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Q & A: Blocking Magnetic Attraction

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Q:
Do Magnets attract metals trough different objects of a seame thickness?
- Alberto Vidal
cartagena,bolivar,colombia
A:
Alberto -

How well magnets work through different objects depends on the object and how thick it is. If the object is something that isn't magnetic at all and doesn't normally stick to a magnet, then it won't matter exactly what it is. For example, if I have a chunk of glass and a chunk of plastic, the magnet will act almost the same through either. So if I were to measure the magnet's strength on the other side (from the same distance away, since magnets do normally get weaker as you get farther away), I would see just about the same thing as if I just did it through air.

I put a piece of iron (sometimes called a "keeper") across the poles of a magnet, this tends to make the magnetic field stay inside the keeper rather than extending as far as id did before the keeper was added.

-Tamara

(republished on 07/13/06)

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