The Dynamo Machine


Objective: To demonstrate how the dynamo machine works and to compare the machine to the earth's dynamo.

Materials needed:

Demonstration:

Mount the dynamo apparatus onto the mounting board with the six bolts provided. The battery can be tested by briefly touching the bared closing circuit wire to the battery to see if the bulb lights. Place the stand on the mounting board and lock the bike into the stand, tightening the knob on the stand so that good pressure is placed on the bike tire. Then connect the stand to the dynamo apparatus with the pulley belt and make sure that the setup is in line and tight. To begin the demonstration, first have someone pedal the bike without closing the circuit (the bulb will not light and pedaling should be fairly easy). Then, while the person is still pedaling rapidly, close the circuit by briefly touching the bared wire to the positive battery terminal. Now the bulb is lit and pedaling should be quite difficult (the pedaler is providing mechanical energy to feed the alternator's electromagnet and the light bulb). Finally, have the person stop pedaling. The light goes out and resuming pedaling will not light the bulb without the circuit being re-closed.

Illustrated is the dynamo machine setup.