How do we change colour?

1. How do we change colour? Kat Street

2. The Spectrum • White light is made up of many different colours. • The range of colours in white light is called the spectrum. • Refraction through glass or water can split white light into its spectrum.

3. Mixing Colours • Light has three primary colours. • They are: • Red • Blue • Green (it’s different from paintbox primary colours!) • Colours can be mixed to make other colours and white light.

4. Red Magenta Yellow White Blue Green Cyan

5. Colours we see • Colour filters absorb some light and only allow one colour through. Red filter White light (all colours)

6. Coloured Objects • Objects that reflect all the colours in white light look white, because all the colours get back to your eye. • Opaque objects absorb some colours and reflect others. Their colour depends on the colour they reflect. For example, green objects absorbred and blue light and reflectgreen. • Objects that absorb all the colours of white light look black.

7. ? What colour would it be in red light…? Green box in white light A green box in red light would appear black because it absorbs all the available colours. Coloured Objects - questions • What colour would a green box be in red light? • Which colours do you think water absorbs? (Think about what colour deep, clear water appears to be.) • What colour is the light from street lamps? If you were outside at night, near a street lamp, what colour would your blue jeans appear to be?