Alright, there wouldn't be color for this reason:
When the light passes into a material at an angle, the light beam is bent or refracted according to Snell's Law and the index of refraction of the material. But also, the speed of light through a material varies slightly with the wavelength or frequency of the light. Thus, each wavelength is refracted at a slightly different angle when passing through a material at an angle. This spreading out of the beam of light is called
dispersion or chromatic dispersion. This can be seen when sunlight passes through a glass prism. When sunlight passes through a prism, it sends colors out from there. ROYGBV (Red, Orange, Yellow, Green, Blue, Violet) are the colors that are separated when white light shoots through a prism at an angle. You'll see a certain color depending on its wavelength. A wavelength is the distance between each wave. If the wave are closer together, then there is a high frequency and high energy, thus giving you the colors blue or violet. And it is the opposite when seeing red or orange. It continues on like that.
So basically, this is happening:
That's why there wouldn't be color if this wasn't happening.
(I love science...so I just had to answer this this way.
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