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Faraday Cage


A Faraday cage made with steel mesh around an aluminum frame. Includes a compact fluorescent bulb which lights up the presence of a strong alternating electric field.


Demonstrate induced current, Gauss's law, electric potential, and the behavior of Faraday cages.


  • Faraday cage
  • Compact fluorescent bulb
  • Two meter sticks with elastic bands (handles to hold the Faraday cage away from the body)
  • Meter stick with screw on end (handle to hold CFL away from the body, outside of the cage)

This should be used with one of the following:


Begin by demonstrating how the CFL behaves in the presence of the high-voltage source when unshielded. Do this by placing the CFL in it's cork holder, and then placing the cork holder on the end of the meter stick with the screw on the end. You may want to use some elastic bands to ensure it doesn't come off. Next, place the CFL into the Faraday cage and close it. Use the other two meter sticks as handles (which go through the slots on the bottom of the Faraday cage) to bring the Faraday cage close to the high-voltage source. You should observe that the bulb no longer lights up.


Any fluorescent bulb should behave similarly in the presence of a strong field. In addition to the CFL we also have a long fluorescent bulb on another meter stick.

Tinsel may be used in the place of the CFL.

As with any demonstration involving high voltages, take extreme caution. Be certain to keep all parts of your body well away from anything conductive during the demonstration.

Demo room information

Location P2
Maker Unknown
Current State Working
demonstrations/5_electricity_and_magnetism/5b_electric_fields_and_potential/faraday_cage/start.txt · Last modified: 2020/01/28 18:18 by demoroom