7A10.42 - Photoelectric Relay

Code Number:
Demo Title:
Photoelectric Relay
Photoelectric Effect
Area of Study:
Modern Physics
Flashlight and Photoelectric Relay.

Set the demonstration up as shown, substituting a Variac and light bulb for the flashlight if desired.  Turn on the relay and allow it to warm up for at least 30 seconds.  Aim the flashlight at the window in the phototube.  The light bulb should light up when light falls on the phototube and go off when the light is removed.

  • G. D. Freier and F. J. Anderson, "Ok-4. Photoelectric Effect Produced with Ultraviolet Light", A Demonstration Handbook for Physics.
  • G. D. Freier and F. J. Anderson, "Ok-3. Photoelectric Effect", A Demonstration Handbook for Physics.

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