Like white is the absence of color. And black is all colors combined ?
That depends. If you are talking about PIGMENTS, then yes maybe, but in terms of LIGHT, it works the other way. Take a prism. White light is the combination of all colors combined. Black is the absence of color (light). Refracting through the prism, each wavelength of light is refracted differently at a different angle due to the difference in wavelength interacting with the refractive index of the glass. Each wavelength gets separated by the SPEED CHANGE the medium effects! Since violet light has the most energy (shortest wavelength, it interacts the most and gets bent more taking the longest path through the glass. That's why you see all the different colors coming out.
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