State the laws of refraction of light.

When light bends as it enters a new material: 1. The incoming ray, the bent ray, and the perpendicular line all lie on the same flat surface. 2. The amount of bending is consistent and can be calculated using a formula involving the angles.

There are two laws of refraction: First law: The incident ray, the refracted ray, and the normal to the interface of two media at the point of incidence all lie in the same plane. Second law (Snell's law): For a given pair of media and for light of a given colour, the ratio of the sine of the angle of incidence (sin i) to the sine of the angle of refraction (sin r) is a constant. This constant is called the refractive index. Mathematically: sin i / sin r = constant = n21 (refractive index of medium 2 with respect to medium 1). If the first medium is air or vacuum, it simplifies to: n = sin i / sin r, where n is the absolute refractive index of the second medium.