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Colour Chamber

An image of the colour chamber including blue background and coloured items

This experiment investigates how we see colour and how it’s affected by our surroundings.

Australian Curriculum links

  • Science > Physical Sciences > Year 5 > ACSSU080

You'll need

  • An RGB light globe
    • Safety note: For this exercise, we use LED globes as they do not heat up over time.  Fluorescent and incandescent globes can get hot and would be a burning hazard if handled
  • A flexible cord to plug the light into, so you can easily move it into a box
  • A white bin with lid, about 15L
  • A large black shirt or black material (optional)
  • A range of coloured objects
  • Highlighters and coloured textas

Try this

  1. Take the lid off the bin and thread the light cord through the lid. You want to have the light hanging near the top of the box and the lid closed as much as possible to minimise external light entering the bin.
  2. Place various coloured objects in the bottom of the box.
  3. Switch the lamp on and look inside the box. You may want to cover yourself with the black shirt or material as you look in to the box to help block external light.
  4. Change the colour of the light using the remote control.  Explore the different colours to see how things change.
  5. Repeat the process with messages written on paper using highlighters and coloured textas.

Further investigation

  • Try putting different objects in the coloured light. Do they appear to change colour? Do some objects appear to change colour more than others?  Why do you think this is?
  • Write messages with different coloured textas.  Can you make your message disappear?  Why does the message disappear?
  • Can you work out how we see different colours?  What coloured light do we need to “see” the different coloured objects?

What’s happening?

The colour of an object is not an inherent property of an object. Instead, the colour of an object is dependent on the light that is shining on it. A granny smith apple isn’t green; instead, when we see the apple under sunlight, the green light is absorbed, while all other colours are reflected. If we shone a red light onto the green apple, it would appear black, as all the red light would be absorbed by the skin of the apple and no light would be reflected.

Further information

To explore more on the perception of light and colour (for older students) check out the following YouTube clips: