6F10.45 - Complementary Shadows

Code Number:
Demo Title:
Complementary Shadows
Colors and Spectrum
Area of Study:
Fluorescent light wand, 12 V battery, Power strip with red, blue, and green bulbs with switches, White Paper Screen.

Turn on either one of the light wands and point towards a white screen or background.  The color will appear white until some object is placed between the light and the screen.  At that point secondary colored shadows will be produced (Cyan, Magenta, and Yellow).

  • Gorazd Planinsic, "Color Mixer for Every Student", TPT, Vol. 42, #3, Mar. 2004, p. 138.
  • Cruse Melvin and Timothy Melvin, "Mixing Colors in the Hall", TPT, Vol. 33, #5, May 1995, p. 292.
  • Martin Gardner, "Colored Shadows", TPT, Vol. 31, #9, Dec. 1993, p. 554.
  • "Figuring Physics",  TPT, Vol. 28, #6, Sept. 1990, p. 430.
  • Robert Gardner, "Colored Light and Shadows", TPT, Vol. 16, #7, Oct. 1978, p. 477, also A Potpourri of Physics Teaching Ideas - Optics and Waves, p. 176.
  • O-750: "Flashlights & Colored Shadow", DICK and RAE Physics Demo Notebook.
  • Pat Murphy, Ellen Macaulay, and the staff of the Exploratorium, "Colored Shadows", Exploratopia, p. 315.
  • Martin Gardner, "Colored Shadows", Science Tricks, p. 63.
  • Martin Gardner, "Color Complements", Entertaining Science Experiments with Everyday Objects, p. 79.
  • "Experiment with Colored Electric Lamps", The Boy Scientist, p. 100.
  • Jearl Walker, "7.40, Colors of Shadows", The Flying Circus of Physics Ed. 2, p. 320.
  • Kelvin Trefz, "Simple AC Demonstrator", PIRA Newsletter, Vol. 13, #17, Jan. 1990.
  • Raymond Bruman, "Colored Shadows", Exploratorium Cookbook I, p. 28.1 - 28.2.
  • Bobby Mercer, "Crazy Shadows", Junk Drawer Physics, p. 104.
  • C. Harvey Palmer, "Experiment A19: Demonstration of Color By Contrast", Optics - Experiments and Demonstrations, John Hopkins Press, 1962.

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