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Benham's Disk (continued)
Step-by-Step Procedure:
1. Take out your scissors and cut out your Benham's disk template
2. Take out your glue stick, apply glue to the disk template.
3. Carefully place the template on the compact disc.
a. Make sure the hole in the center of the template goes throughthe stick of the top
b. Smooth the template down to make sure the glue and paper stick to the compact disc.
4. Now, spin your top and look at the patterns on the disc.
5. What colors do you see?
6. Now, let's dim or turn off the lights.
7. Do you see the same colors? Why not?
Expected Results:
Results may vary based on materials used, setup, procedure, and other factors, however, here are a few examples on what to expect:
• The retina of the eye is composed of two types of receptors sensitive to light: cones and rods. Cones are important for color vision
and for seeing in bright light. There are three types of cones, each of which is most sensitive to a particular wavelength of light. Rods
are important for seeing in low light.
• When we dim the lights, our cones cannot see light as well; we rely on the rods to help us see in the dark. But, rods only help us see
black and gray in the dark.
• One possible reason people see colors may be that the rods and cones in the human eye respond at different rates to red, green,
and blue. But honestly, we don't really understand how this happens. It's still a mystery to this day!
