In this electromagnetic induction apparatus, a metal conductor is mounted between bearings so that it can be rotated like a single blade of a paddle-wheel. A long slim cylindrical permanent magnet is slid through the bore of one bearing so it is supported horizontally. The length of the magnet lies parallel to the conductor and the tip of the magnet is about half way along the length of the conductor.
When the conductor is rotated, it is obvious that it would cut through all the lines of force that we imagine ‘mushroom’ out from the end of the magnet. Each bearing has a metal contact rubbing so that any voltage or current produced in the rotating conductor can be detected by a meter connected to the bearings.
The device is to prove the following:
That a voltage is produced when a conductor cuts magnetic lines of force.
That the voltage is present while the conductor is cutting through the magnetic field.
The voltage generated is proportional to the speed of rotation.
A simple DC generator can be made that does not require a commutator.
Examine the principles of Faraday’s generator.