Cambridge IGCSE Physics · Syllabus 0625 · Waves
Dispersion of light
What is Dispersion of light?
The separation of white light into the colours of the visible spectrum, which happens because a medium such as glass slows each frequency by a slightly different amount. Violet light is slowed most and is deviated most; red is slowed least and is deviated least. A prism does not create the colours, it separates colours already present in the white light. In order of increasing frequency the traditional seven colours run red, orange, yellow, green, blue, indigo, violet, and in order of increasing wavelength that order is reversed.
This definition is part of the Waves chapter in Cambridge IGCSE Physics.