Question

what happen to light when it moves from denser medium to rarer medium?

Answer 1

When light moves from denser medium to rarer medium ( eg:- passing from water into air )the light is refracted ( or bend) away from the normal

Answer 2

when a ray of light passes through a denser medium the ray refracts away from the normal.
the angle and the wavelength at which light enters and the density of the substance determine how much light is refracted.
i hope this helps u...