Name: Christopher S.
Status: educator
Age: 50s
Location: N/A
Country: N/A
Date: Thursday, November 28, 2002
Question:
This question is about reflection of light. How is
it that a particular substance can reflect a certain frequency of
light? Is it actually absorbed then emitted, or does that wave
"bounce around" then come back. I have a basic, IGCSE, understanding
of absorption and emission spectra but the nature of reflection is
unclear to me.
Replies:
Christopher,
I am not aware of any substance that reflects only one frequency of
light. Rather, reflection is usually for a large range of frequencies.
Color is imparted to the reflected light because the reflecting surface
absorbs some frequency ranges more than others. The reflected light
therefore is dominated by the non-absorbed light frequencies. Thus a
red piece of paper reflects some light in all ranges but most of the
light in the blue through orange range is absorbed. The reflected light
is therefore dominated by red light.
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