I understand that light of different wavelengths reflected is what gives off color but what determines which wavelengths, a table, for example, will reflect or absorb? Is it something encoded in the table itself or is it the light that communicates the color?
Why do some things absorb all wavelengths turning them black while others reflect all turning them white?
In: 7
> encoded in the table itself
What?
There are actually two parts to color perception. Wikipedia leads with “the visual perception based on the electromagnetic spectrum.” https://en.wikipedia.org/wiki/Color (which is a decent primer to read for background information.
What the brain perceives as a given color depends on the relative strengths of the stimuli of the cone cells in the eye’s retina. A bunch of red photons will stimulate the ‘red’ cell a lot and the ‘green’ and ‘blue’ cells little. A single wavelength of light is perceived as a [spectral color](https://en.wikipedia.org/wiki/Spectral_color). But “all the colors of the rainbow” is a very narrow set of colors. Different wavelengths correspond to different energies. As you go toward red (and past that into infrared) the energy is lower. Opposite for violet, ultraviolet, etc.
Electrons in different chemical compounds exist at energy levels, kind of like a ladder or staircase. You can’t stand halfway between two rungs. An electron needs energy input to go up, and can drop back directly down or take intermediate steps down. Like jumping three steps up, and walking down a step at a time.
The analogy I came up with before is if when you hear a certain note you can jump up a certain amount, and when you jump down, you sing the corresponding note.
So if a [dye](https://en.wikipedia.org/wiki/Dye) molecule has an electron structure that has the right gaps, it will absorb those light colors.
This only covers a relatively small part of the concept but hopefully is enough to get you started reading already-written stuff.
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