Question

Define refractive index in terms of speed

Answer 1

Refractive index, also called index of refraction, measure of the bending of a ray of light when passing from one medium into another. ... Refractive index is also equal to the velocity of light c of a given wavelength in empty space divided by its velocity v in a substance, or n = c/v.

Answer 2

refractive index(n)=the speed of light in vaccum(C)/the speed of light in medium(v)

n=C/v