Speed of light in glass is dependent on the colour of light as different colours have different wavelengths, thus different velocities.
We know that refractive index of a material in terms of the wavelength of light is
μ = a + (b/λ2)
As the wavelength of violet light is smaller than that of red light,
μv > μr.
We also know that
⇒ vv < vr
Hence velocity of violet light in glass is less than velocity of red light.
Rate this question :