Using experiments, animation and diagrams, this film shows and explains discharge patterns in rarefied gases. Studies the phenomena produced inside a glass tube fitted with two electrodes when a high voltage is applied and the air pressure in the tube is reduced by a vacuum pump. Starting from spark discharge in air, the parts of discharge are identified; deflection of cathode rays by magnetic or electrostatic fields, ionization by collision, breakdown voltage and excitation of the atom by free electrons are explained.
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How to watch
Collection
In ACMI's collection
Credits
Collection metadata
ACMI Identifier
002861
Language
English
Subject categories
Advertising, Film, Journalism, Mass Media & TV → Cathode ray tubes
Mathematics, Science & Technology → Atoms
Mathematics, Science & Technology → Cathode ray tubes
Mathematics, Science & Technology → Gases
Mathematics, Science & Technology → Physics
Sound/audio
Sound
Colour
Black and White
Holdings
16mm film; Access Print (Section 1)