The ratio of sine of the angle of incidence to the sine of the angle of refraction is a constant for a given colour and for the given pair of media. Which law is this?

Explanation

This is Snell's Law. Snell's Law states that the ratio of the sine of the angle of incidence (θ1)) to the sine of the angle of refraction (θ₂)) is constant and is equal to the refractive index (n) of the second medium relative to the first medium. Mathematically, it is expressed as: sin θ1 / sin θ₂ = constant This constant is the ratio of the refractive indices of the two media involved. Snell's Law can also be written as: n₁ sin θ₂ = n2 sin θ₂ where n₁ and n₂ are the refractive indices of the first and second media, respectively.