Physics for IGCSE & O level - Rays And Waves (Section 3 - No. 9)
What is the definition of a refractive index?
A measure of the speed of light in a medium.
The ratio of the speed of light in vacuum to the speed of light in the medium.
The amount of light bent by a lens.
The angle of incidence divided by the angle of refraction.
Giải thích
The refractive index is defined as the ratio of the speed of light in a vacuum to the speed of light in the medium.