Absorbtion and Reflection of Objects, question

In summary, the conversation discusses the concept of color and how it is perceived by our eyes. The question is raised about why certain objects reflect specific wavelengths of light to exhibit a certain color, and what factors determine this. It is suggested that this may be due to the energy levels of the material involved, as well as the absorption and emission spectra phenomena. The wavelength absorption band is also mentioned, along with the possibility of transitions between energy levels within valence or between valence bands. The idea of polarized light, such as Brewster's angle, is also brought up in relation to colored surfaces.
  • #1
cjahoda
1
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
  • #2
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.
 
  • #3
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
 

1. What is the difference between absorption and reflection of objects?

Absorption refers to the process in which an object takes in or absorbs light energy, while reflection is the process in which an object bounces off or reflects light energy. In other words, absorption results in the object appearing darker or duller, while reflection results in the object appearing brighter or shinier.

2. What factors affect the absorption and reflection of objects?

The color and texture of an object are two major factors that affect the absorption and reflection of light. Darker and rougher objects tend to absorb more light, while lighter and smoother objects tend to reflect more light. The material of the object can also play a role, as some materials are better at absorbing or reflecting light than others.

3. How does the absorption and reflection of objects relate to their temperature?

Objects that absorb more light energy also tend to absorb more heat energy, which can lead to an increase in temperature. On the other hand, objects that reflect more light energy tend to reflect more heat energy, which can lead to a decrease in temperature. This is why darker objects tend to feel warmer than lighter objects on a sunny day.

4. Can objects absorb and reflect different types of light?

Yes, objects can absorb and reflect different types of light, such as visible light, infrared light, and ultraviolet light. The amount of each type of light that is absorbed or reflected depends on the properties of the object and the wavelength of the light.

5. How does the absorption and reflection of objects impact their appearance?

The absorption and reflection of light is what allows us to see objects in different colors and textures. For example, a red apple appears red because it absorbs all other colors of light except for red, which it reflects. The same concept applies to the appearance of our surroundings, as the absorption and reflection of light by objects determine the colors and textures we see.

Similar threads

Replies
3
Views
1K
  • Optics
Replies
7
Views
1K
  • Optics
Replies
4
Views
656
Replies
3
Views
901
Replies
28
Views
3K
Replies
4
Views
791
Replies
20
Views
5K
Replies
7
Views
2K
Replies
26
Views
4K
Replies
21
Views
4K
Back
Top