Week 2 Answer:

Last week Science Spark looked at how colours are perceived. The question posed was:

If you mix red paint and green paint, you get brown paint. But what colour would you get if you mix red light and green light?

a) Brown light
b) Yellow light
c) Purple light

The correct answer is b) yellow light.

Why does mixing paint and coloured light produce such different colours? Your eyes respond to different wavelengths of light and perceive them as different colours. When you mix equal amounts of blue, red and green lights, you get white light. These three colour lights are known as the primary colours of light.

The colour you see on an object, however, is produced when the object reflects certain wavelength of light. For example, an apple looks red because it absorbs all other colours, but reflects red light. Similarly, paints get their colours because of the light that they reflect. For this reason, mixing the same set of coloured light and paint give you very different results.

The diagram above shows what happens when you mix coloured light and paint. Notice that the secondary colours of light are actually the primary colours of paint, and the secondary colours of paint are the primary colours of light.

The mixing of coloured lights is known as additive colour mixing. The three primary colour lights add together to make white light. The mixing of paints is known as subtractive colour mixing. When you mix all the primary colours of paint together, the paint appears black as all the lights are absorbed.
To find out more, try some of the links below.

Useful links

http://home.att.net/~B-P.TRUSCIO/COLOR.htm

http://home.att.net/~RTRUSCIO/COLORSYS.htm

http://www.bracknet.com/ess/Graphics/colourT.htm

The WINNER for this week 2 Science Spark Quiz is:
Mr Mohamad Ridzuan
IC: S7617739B