Why does the human eye perceive a red colored dress as the red color?

We have a 3-colour vision which happens to be the primary colours: red, blue and yellow. So, we can see red, and that is why we see it.

To see other we just mix the different cells as if we where mixing paint to get a new colour.

Hope it was easy to understand,

Happy homework/ study/ exam!

E = hf 
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