Refraction is a phenomenon in which a light wave bends or changes its direction when passing through a medium with a refractive index different from the other medium.
Being the refractive index [tex]n[/tex] is a number that describes how fast light propagates through a medium or material, and is defined as the relation between the speed of light in vacuum ([tex]c=3(10)^{8}m/s[/tex]) and the speed of light [tex]v[/tex] in the second medium:
[tex]n=\frac{c}{v}[/tex]
It is important to note that in this process, the wavelength may be modified because it depends on the medium, however, the refracted ray of light does not change its frequency.
