School of Physics Lecture Demonstration Manual

El-13 Faraday's Cage

Published: Tuesday 14 March 2006 - Updated: Thursday 31 March 2011

Aim

To demonstrate that there is no electrostatic field inside a statically charged conductor.

Apparatus

Diagrams

Click on pictures to enlarge.

Faraday's Cage Diagram

Description

An electroscope is placed inside the large Faraday cage about 2 metres from the Van de Graaff. Starting the Van de Graaff produces no deflection of the leaves of the electroscope whereas an equivalent electroscope outside the cage diverges.

Alternatively a transistor radio may be placed upon a sheet of aluminium. Enclosing the radio with the wire mesh cage causes a dramatic decrease in sound level.

Safety notes

Electrical safety 

Maintenance 

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