7A10.30 - Photoelectric Effect Demo
Set the demonstration up as shown. The filters will show at which spectral wavelengths the photocell works best. The photocell shown and the others that are available do not work exactly like the classical cells described in most of the text books because they are made of other alloys than those in the texts. Therefore the filters used for maximum effect are also in a different region of the spectrum and also have a broader bandwidth.
Another simple way to show that the shorter wavelengths contain most of the energy is to use different color LED's with some fluorescent material. The material will not be activated with the red, orange, yellow, and green lights. The blue and white lights will give some activation, but are nothing compared to the activation provided by the ultraviolet light.
The Cenco units will also show the photoelectric effect using different colored filters and an incandescent light. These are intended as a lab experiment and therefore not as large and visual as the setup described in the first paragraph.
- Adolf Cortel, "Tweaking 'Simple Photoelectric Effect' Demo", TPT, Vol. 44, # 7, Oct. 2006, p. 406.
- Adolf Cortel, "Simple Photoelectric Effect", TPT, Vol. 44, # 5, May 2006, p. 310.
- Wayne P. Garver, "The Photoelectric Effect Using LEDs as Light Sources", TPT, Vol. 44, #5, May 2006, p. 272.
- Adolf Cortel, "Demonstrating the Relationship Between the Energy and Frequency of Light", TPT, Vol. 38, # 3, p. 152, March 2000.
- Dr. Hanna Goldring, "Correction Corrected", TPT, Vol. 17, # 7, Oct. 1979, p. 416.
- S.B. McKagan, W. Handley, K.K. Perkins, C.E. Wieman, "A Research-Based Curriculum for Teaching the Photoelectric Effect", AJP, Vol. 77, # 1, Jan. 2009, p. 87.
- Yaakov Kraftmakher, "Photoelectric Effect Experiment with Computer Control and Data Acquisition", AJP, Vol. 74, # 10, Oct. 2006, p. 941.
- Jearl Walker, "Simple and Vivid Demonstrations of Advanced Concepts in Physics", The Amateur Scientist, January, 1983.
- Yaakov Kraftmakher, "6.4 Photoelectric Effect", Experiments and Demonstrations in Physics, ISBN 981-256-602-3, p. 389.
- "The Photoelectric Effect", Selective Experiments in Physics, CENCO, 1962.
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