1. Snell’s law is defined as “The ratio of the sine of the angle of incidence to the sine of the angle of refraction is a constant, for the light of a given colour and for the given pair of media”. Snell’s law formula is expressed as:
sin i / sin r = constant = μ
Where i is the angle of incidence and r is the angle of refraction. This constant value is called the refractive index of the second medium with respect to the first.
2. The point on the spherical surface of mirror through which principal axis passes is called as pole of the concave mirror.
