BCIT Physics Department

Demonstration Manual

Electricity and Magnetism

DEM51 - Vibrating Filament Demonstration


- To show that the filament is carrying an alternating current.



The filament being powered by AC will vibrate 60 times per soncond when a magnet is brought near it. The DC powered filament will not appreciatively respond to the magnet.

The alternating magnetic field produced by the AC current is responsible for the vibrations in the presence of an external magnetic field.