Question

when light travels from a rarer to a denser medium, the speed decreases. Does this decrease in speed imply a decrease in the energy carried by the light wave? Justify your answer

Answer 1

The energy of a photon of light is given by, E = hν

‘h’ is Planck’s constant and ‘ν’ is the frequency.

When there is a change in medium the frequency of light remains constant and the wavelength of light changes. Thus, the energy of light remains same when it moves from one medium to another.