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I majored in social sciences, so I haven't taken a science class since 1999, so forgive me if I don't ask this right.

What difference would skin color make from a physics perspective?

Would there be any difference in the energy emitted, reflected or absorbed?

Would it affect what is emitted, reflected or absorbed?

Can physics provide an analysis of why paler skin is more prone to melanoma?

Does melanin in an of itself have any physics applications? Is is used in physics experiments, etc.?

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What difference would skin color make from a physics perspective?

Would there be any difference in the energy emitted, reflected or absorbed?

Would it affect what is emitted, reflected or absorbed?

the darker the color the more absorption of sunlight , and since the process is reversible there will be more emission for darker colors.

In skin, the dark color denotes a lot of melanin, and melanin is the defense of the body against ultraviolet radiation from the sun. It does not allow it to penetrate and destroy the lower layers. The first evidence of damage is sunburn.

Can physics provide an analysis of why paler skin is more prone to melanoma?

This is a biophysics question. I believe it is due to the lack of melanin which allows penetration of ultraviolet and mutation of lower level cells that can turn cancerous.

Does melanin in an of itself have any physics applications? Is is used in physics experiments, etc.?

Not that I know of. The use of dark colors when one wants to absorb sun energy (( as in sun water heaters) and light when one wants a lot of reflection (as on rooftops) is of course general.

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Thanx, anna v. You're right, I think there is some biophysics in what I'm asking, but there is one more thing I will ask you, based on your response: In general, when does the fact that a body (i.e. object) both absorbs and emits more or less sunlight? What experiments, studies or fields do you know of that have focused on this? It all sounds strange, I'm sure, but I'm wondering what significance skin color can have beyond it's social and political implications, & skin cancer. Could different skin colors have different physical properties that affect the wearer or those around them –  taj-akoben May 11 at 19:15
    
All bodies of matter emit black body radiation according to their temperature with a coefficient that differs, emissivity it is called. Emissivity plays also the inverse role in absorption of radiation for a given frequency. I do not know if there exists a difference in human skin . Here they think yes juro.uga.edu/2010/boc2010/mize_2010.pdf . In any case it will not be more important than wearing dark or light clothes maybe in a crowd. A white dressed crowd would reflect more light than a dark dressed crowd. –  anna v May 11 at 19:42
    
p.s. It is interesting that I know of one blond German girl married to a Greek whose hair turned brown in Greece. Her melanin went into action not only on her skin ( she was naturally blond). Good night. –  anna v May 11 at 19:47
    
All of this is great; thanx. As for the German woman, this sounds like albinism. Albinism isn't only white hair and red eyes- that's only one of 4 types (which themselves have sub-types). In several of these, a person's hair darkens later in life, and in several, slight pigmentation is possible. I am not a clinician, but I have never heard of hair color changing later in life, as you described. Interesting... –  taj-akoben May 11 at 20:44

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