This fun relay game challenges the students' memory of the colour sequence of a rainbow.
The range of wavelengths of light that the human eye can see is called "the visible spectrum". This includes the colours of the rainbow.
Each colour can be explained as a ray of light that is transmitted at a particular level of energy (with a particular wavelength):
|Colour||Wavelength Range (nm)|
The range of wavelength for indigo is around 425–450 nm. It's hard for the human eye to distinguish and is usually considered a subset of violet.