Unformatted text preview: Falling water pushes against the blades of a turbine, causing the rotor of an AC generator to spin. The spinning rotor causes a coil to turn in a magnetic field, which creates an induced emf in the coil. This induced emf is the voltage source for the current in our electric power lines. As the bar magnet falls toward the ring, a magnetic field is produced by the ring that opposes the change in flux through it. The net result is an upward force that prevents the bar magnet from experiencing free fall. As the magnet moves at high speed past the fixed coil, the magnetic flux through the coil changes very rapidly, increasing as the magnet approaches the coil and decreasing as the magnet moves away. The rapid change in flux through the coil induces a large emf, large enough to cause a spark across the gap in the spark plug....
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- Spring '09
- Magnetic Field, electrical energy, Magnet, bar magnet, Faraday's law of induction