Visible Light
Light Sound and Waves

A spectrum of colours

Physics Narrative for 11-14 Supporting Physics Teaching

Noticing and accounting for colour

A white light source emits a whole range of frequencies. You can select some frequencies by filtering or by dispersion. These selected beams will all be of a limited range of frequencies, and so close to one spectral colour.

Paint has a particular colour because it only reflects a certain range of frequencies. If that range is not in the beam shone on the paint, then nothing gets reflected.

The eye has only three colour sensors: hence the three-colour theory of vision. Different combinations of spectral colours can all appear to be the same perceptual colour.

IOP DOMAINS Physics CPD programme

Waves CPD videos

Our new set of videos gives teachers and coaches of physics a preview of the training we offer ahead of this term's live support sessions.

Find out more