Absorbtion and Reflection of Objects, question

  • Context: High School 
  • Thread starter Thread starter cjahoda
  • Start date Start date
  • Tags Tags
    Absorbtion Reflection
Click For Summary
SUMMARY

The discussion centers on the principles of light absorption and reflection as they relate to color perception in objects. Specifically, it addresses why a red apple reflects red wavelengths while absorbing others, linking this phenomenon to the energy levels of the material's atoms. The conversation highlights that the reflection and absorption of light depend on the energy transitions within the material, rather than solely on the light's properties. Additionally, it mentions the role of polarized light in reflection, particularly in shiny surfaces.

PREREQUISITES
  • Understanding of light wavelengths and color perception
  • Basic knowledge of atomic energy levels and electron transitions
  • Familiarity with the concept of polarization in light
  • Awareness of Brewster's angle and its implications in optics
NEXT STEPS
  • Research the relationship between atomic energy levels and light absorption
  • Explore the principles of polarization and its effects on color perception
  • Study Brewster's angle and its applications in optics
  • Investigate the emission spectra phenomena in different materials
USEFUL FOR

Students of physics, optical engineers, and anyone interested in the science of color and light behavior in materials.

cjahoda
Messages
1
Reaction score
0
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.
 
Science news on Phys.org
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
 

Similar threads

  • · Replies 10 ·
Replies
10
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 15 ·
Replies
15
Views
4K
  • · Replies 7 ·
Replies
7
Views
2K
Replies
9
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 4 ·
Replies
4
Views
1K
  • · Replies 20 ·
Replies
20
Views
6K