Al Tobias (wat4y) - Office: Gibson S123 & Physics 218, (434) 924-0538
Demonstrations are cataloged according to PIRA Bibliography
PLEASE REQUEST DEMOS WELL IN ADVANCE
Due to Physics Building renovations, the lead time to set up demo requests has increased due to the need to transport equipment across campus. Please be kind and let me know well ahead of time what you need.
Choose a Topic or Enter a keyword to search:
You have selected the following Demos:
video - e/m Tube Lorentz Force Demonstrator
Purpose:The electron beam of an e/m tube in Helmholtz coils is shown under various electric or magnetic field configurations.
Turn ON 5 minutes before use. Even if beam is visible, it takes 5 minutes before it is bright enough to resolve on a camera!
A Pacific Science Supplies Model P63412 e/m Lorentz Force Demonstrator can be shown with the aid of a video camera in a darkened room. It is possible to bend the e- beam in a circle and spiral by adjusting the orientation of the tube and the current of the Helmholtz coils. The electron beam is visible due to the tube vacuum containing a trace of inert gas (argon?). Ionization of the gas around the electron beam creates a glowing discharge marking the path of the electrons.