The River Thames outside DLD College London

Colourful Physics

10th December 20

Year 13 A level Physics students have been looking at a neon tube through a diffraction grating, which splits up the red-orange neon colour into an emission spectrum.

Each line is caused by an electron dropping down one or more energy levels in the neon atom and emitting a photon. The colour of the photon depends on the size of the energy gap.

This process is used to observe the light from galaxies; red shift of the light is evidence for the expansion of the universe.

Dr Louise Affleck, Director of Studies and Physics Teacher