1 Refraction of Light: It has been observed since ancient times that light refracts or "bends" as it
travels from one medium to another (from air to water, for example). If V1 is the speed of light
in one medium and V2 its speed in another medium, then according to Snell's Law, *
Snell's Law: (sin01/sinO2)=(V1N2)
where 0, is the angle of incidence and 0, is the angle of re-
fraction (see the figure). The number v1/v2 is called the index
of refraction. The index of refraction for several substances is
given in the table.
If a ray of light passes through the surface of a lake at an
angle of incidence of 70°, what is the angle of refraction?