Visible Light
Light, Sound and Waves

Colours - adding and removing

Teaching Guidance for 11-14 Supporting Physics Teaching

Lighter or darker

Wrong Track: We've done about colours in art, and the more primary colours you add, the darker it gets.

Right Lines: Adding different coloured beams of light heading towards your eye makes things lighter. Reflecting beams off many different surfaces makes things darker, as with painting.

More or fewer frequencies of light

Thinking about the learning

You need to be very clear about the distinction between situations where more and more frequencies are added to the light that hits the eye, and those where the frequencies that hit the eye are reduced. The first one happens when you bring beams of light together, the second when diffuse reflection subtracts parts of the incident beam.

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