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Q & A: Theories About Color

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Most recent answer: 10/22/2007
Q:
I need some evidence on the subject on of color absorbtion. The theory is, is that things only reflect the colors that they are not. For example, the grass is not green, it is only the color that it is not, it is the color that it does not absorb, so under that theory, black people arent balck and white people arent white. Also, when the lights are all turned off, what color are things?, Thats right, they arent anything, so its all about the light. I desperatly need some evidence and info on this subject. Thanx
- Jamie Besler (age 16)
Woodlands Secondary School, Nanaimo, B.C. Canada
A:
Jamie -

I think what you're dealing with here is more an issue of semantics than science. In other words, I think your question has to do more with the definition of the word "color" than with how light is actually absorbed or emitted. If you were to define something's color as the colors of light being absorbed by the object at any particular time, than your description would be completely correct. However, this is not the definition of "color" that is typically used.

We see most objects only by reflected light. So what we mean by the
color of the object is the color of the light that it reflects when
it is bathed in ordinary white light (a mixture of colors), not the
color of the light it absorbs.



Sometimes objects emit light- say if they're very hot, like the burner of a stove- and the color of that light is usually a lot different from the color of the light that object would reflect.



Usually, though, when we talk about the color of an object, we usually just mean the color of the reflected light.
-Tamara & Mike

(published on 10/22/2007)

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