Electricity & Magnetism

Pedal Generator

This exhibit demonstrates that it takes work to generate electricity. The visitor sits in a chair in front of an antique foot operated lathe. When the lathe is pedaled, the visitor can turn on one or three lights. When the lights are off, it's easy to pedal, when one light is turned on, it becomes much more difficult to pedal, and when three lights are turned on the visitor must pedal at a furious rate to keep all three lamps at the brightness of the original one lamp. The current into and out of the lamps can be monitored. Just as much current leaves the lamps as enters the lamps.