Optic Top - Benham's Disk Sets
Optic Top - Benham's Disk Sets

 

Code Number: 6J11.11

Demo Title: Optic Top - Benham's Disk

Condition: Good

Principle: Integration of Light Pulses by the Eye

Area of Study: Optics, Human Biology

Equipment:

Benham's wheel top, Benham's wheel cutouts, used CD's, pennies, Op-Tric Set.

Procedure:

Spin the disk under bright or normal lighting.  Even though the disk is black and white, when spun the strobing effect will make it appear that the disk has colors.  Reds and yellows are most apparent, but greens and blues can be seen if observed carefully.

The Op-Tric set has several top patterns that will also show colors when spun.  

A set of optics tops are in 6J11.30 with the Zoetrope.

References:

  • Laxmipuram P. Sri Vatsa, "Prevost-Fetchner-Benham Effect", AJP, Vol. 40, #6, June 1972, p. 914.
  • D. James Baker, Jr., "Time Dependence of Flourescent Lamp Emission - A Simple Demonstration", AJP, Vol. 34, #7, July 1966, p. 627.
  • C. L. Strong, "The Amateur Scientist: "Generating Visual Illusions with Two Kinds of Apparatus",  Scientific American, Vol. 224, # 3, March 1971, p. 110.
  • George M. Hopkins, "Experiments with the Scientific Top", Experimental Science, p. 174.
  • Paul Doherty, Don Rathjen, "Benham's Disk", The Cheshire Cat, p. 12.
  • Martin Gardner, "Swizzle-Stick Code", Entertaining Science Experiments with Everyday Objects, p. 72.
  • Martin Gardner, "Color That Isn't There", Entertaining Science Experiments with Everyday Objects, p. 71.
  • Robert L. Wild, "Psychological Color - B/W Disk Plus Stripes", Low-Cost Physics Demonstrations # 170, p. 96.
  • 5.130:  Jearl Walker, "Colors in a Black and White Disc",  The Flying Circus of Physics with Answers.
  • 5.131:  Jearl Walker, "Color Effect from Fluorescent Lights",  The Flying Circus of Physics with Answers.
  • Janice VanCleave,  "Color Trickery",  Gooey, Slippery, Slimy, Weird, & Fun Experiments, p.  38.
  • Janice VanCleave,  "Color Trickery",  Biology for Every Kid - 101 Easy Experiments That Really Work, 162-163.
  • Raymond Bruman,  "Three Spinners",  Exploratorium Cookbook I, 41.1 - 41.4.
  • "Benham's Disk",  The Exploratorium Science Snackbook, 5.1 - 5.2.
  • R.D. Edge, "Benham's Top", String & Sticky Tape Experiments, p. 13.01.