This demonstrates that a changing magnetic field causes a potential
difference (voltage) in a conductor. This concept is called Electromagnetic Induction.
Electromagnetic Induction is the principle used in electric generators (also called
alternators), microphones, electric guitars, transformers, and Tesla coils. (see
the induction devices) One more thing
you should notice is that the current created in this conductor is alternating current
because it flows back and forth. This is a result of the conductor being raised then
lowered in the magnetic field. This should begin to give you an idea of why our household
current is alternating.
©1998 Science Joy Wagon