Question

Do light waves of different colours all travels at the same speed in
glass? Explain.
b) Determine the speed of yellow light with wavelength λ = 589 nm
in diamond. The refractive index of diamond is 2.42.

Answer 1

a) Yes, light waves of different colors all travels at the same speed in glass. Their speed is

v=c/n_glass .

It doesn’t depend on wavelength.

b)

v=(3.00∙〖10〗^8)/2.42=1.24∙〖10〗^8 m/s.