7D10.80 - Cosmic Rays

Code Number:
Demo Title:
Cosmic Rays
Observing Cosmic Rays
Area of Study:
Modern Physics
Cloud Chamber, Dry ice for Cloud Chamber, Radioactive Source for Cloud Chamber, Ethyl Alcohol, and Camera with Power Supply.

See also 7D10.80 in Astronomy.

The chamber should be set up as described in the manual in the file. Care should be taken to insure that the black plate in the chamber is level. The chamber is attached to a leveling stand with Velcro so that this may be done. Turn the fluorescent light on as soon as possible or the ballast may get to cold to activate. Place the camera as shown over the glass window in the top plate.  Close-up lenses are not needed if you use the macro part of the lens on the camera. The ion trails should appear in 5 to 15 minutes after the final step of activation and last for several hours.

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