How about this?
If white is a color, then is black a color as well?
Black is the absence of light - so we do not see anything black, but we see
everything that is not black. I do not see my black shirt I see where it is not.
(And of course there is discussion how completely black a surface is ...)
As I understood it, white is a perception created in the brain when we see (very
loosely speaking to the 8th grade) all the colors.
Also, on the subject of color perception, when I show a one of the plasma flower
light bulbs* some students can see a faint purple haze around the orange plasma and
others cannot. I think this maybe the result of being able to perceive color deeper
into the UV. I can see it clearly, and I find that other students with blue eyes
are more likely too as well.
*( this device is a clear glass light bulb with two metal flowers inside almost
touching, one to each potential. When plugged in, an orange plasma coats each
flower. The petals, covered with green florescent paint, glow. A diffraction
grating revealed a spectrum matching mercury.)
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S.Goelzer
Physics Teacher
Coe - Brown Northwood Academy
Northwood NH 03261
603-942-5531 ext43
sgoelzer@coebrownacademy.com
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