• Question: If white light contains light of every color, why does mixing a bunch of paints together make black?

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      Asked by jodlington to Kate, Kieren, Nicola, Rowena, Roy on 14 Mar 2014.
      • Photo: Kate Nicholson

        Kate Nicholson answered on 14 Mar 2014:

        Each of the paints appears coloured because it absorbs all colours apart from the one it appears, so red paint absorbs every colour of light apart from red which is reflected back to your eyes, so it looks red. Ok so far?
        Now if you mix a paint that absorbs everything but red with a paint that absorbs everything but blue then the blue paint absorbs the red that is reflected, the red paint absorbs the blue that is reflected so no light is reflected and it appears black.

      • Photo: Rowena Fletcher-Wood

        Rowena Fletcher-Wood answered on 14 Mar 2014:

        Kate’s explanation is good. The trick is to think uf you add light together it’s white and you subtract colours it’s black. Things look a colour not because they add that colour but because they subtract away all the other colours from light. The more colours you subtract the closer to black so mixing more very different coloured paints makes a darker palette.

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