School of Physics Lecture Demonstration Manual

Eb-3 Faraday's Wheel

Published: Tuesday 14 March 2006 - Updated: Tuesday 29 March 2011


To demonstrate the production of a continuous current (D.C.) by means of electromagnetic induction.



Click on pictures to enlarge.

Faraday's Wheel Diagram


Faraday's wheel consists of a disc capable of rotation about a horizontal axis. The disc rotates between the poles of a strong permanent magnet. Connections are made to the rim of the disc and the axle by aid of perspex cups containing mercury into which the discs A and B make contact.

The galvanometer is connected to the cups and the disc is spun by the connection of a small length of P.V.C. tubing between the axle and the A.C. motor. The variac controls the speed of the motor.

Safety notes

Electrical Safety 

Chemical Safety 


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