Electric Currents and Magnetism


Around a magnet is an invisible force called a magnetic field. Field lines are used to represent where the field is located. We can "see" a magnetic field by sprinkling iron filings on a magnet.
http://m.youtube.com/watch?v=N1as-po1rGw

The movement of charges cause magnetism. Electric currents are basically moving electrons; they produce magnetic fields. If you have a "live" wire, the field lines are in a circle around the wire. In the same way, an electric current can be produced by changing magnetic fields. If you put a metal loop between the south pole and the north pole of two different magnets and move the loop in and out of the fields, you can produce an electric current.

Take a moment to check your understanding with the following quiz:


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Click here to go on. . .