Absorbtion and Reflection of Objects, question

AI Thread Summary
Objects reflect specific wavelengths of light due to the energy levels of their atomic or molecular structures, which determine how they interact with incoming photons. When light hits an object, certain wavelengths are absorbed if they match the energy differences between electron energy levels, while others are reflected, giving the object its perceived color. The reflection can also be influenced by the object's surface properties, such as texture and polarization. For example, shiny surfaces may reflect light differently than matte surfaces, affecting color perception. Understanding these interactions helps clarify why a red apple appears red, as it reflects red wavelengths while absorbing others.
cjahoda
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I have a question which may be based in a complete misunderstanding of how "color" and our perception of it works in terms of objects absorbing certain wavelengths of light and reflecting a certain length to show that color.

My question is why does an object reflect a specific wavelength versus another? To be cliche, why does a red apple reflect the wavelength that exhibits red to our eyes?

What, on the object's surface, decides what is reflected or absorbed? Or is this altogether more dependent upon how our eyes work versus light and its being taken in by objects' surfaces?

I'm not sure if I'm being clear. I've tried multiple different inputs into Google to try to find an answer but the information always is about how different wavelengths exhibit different colors and it depends on what the object reflects; but never why.

Any insight is appreciated.
 
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It probably has to do with the energy levels of the material involved. If light of a particular frequency and hence photons of a particular energy matching the energy difference between a higher and lower energy level, then the atoms or electrons in the material would absorb these photons and transit to the higher energy level. Thus only specific frequencies of light corresponding to the energy differences are absorbed vis-a-vis the emission spectra phenomena.
 
Hi cjahoda-
The wavelength absorption band is too wide to represent transitions between bound atomic energy levels in individual atoms. The transitions would have to be between energy levels within valence or between valence bands.
The light reflected off of colored surfaces, especially specular reflection off of shiney painted surfaces, is usually polarized, like for example Brewster's angle.
Bob S
 
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