How does the object know what colour to reflect so we can see it?

Question

Already asked this question...but let me give another situation.

People said that it's all in the nature of the surface. but how come any surface i paint with red paint turns red?

what if i make a dent in the surface? will it chance color? the angle light comes in changes do does the surface. Enlighten me.

Answer 1

When you paint a surface red, the light hits the paint, not the surface underneath. Denting the paint doesn't change it, it's still red paint. But if you scrape some of the paint off to expose the original surface, then you see the original color.