Question

State Snell’s law of refraction of light.

Answer 1

Hint:Refraction is the bending of the light when it passes through the different medium of the isotropic media like the glass, air or the water. The snell’s law gives the relation between the angle of the incidence and the angle of the refraction of the light.

Useful formula:
The snell’s law of refraction is given by
$\dfrac{{\sin i}}{{\sin r}} = \dfrac{{{n_i}}}{{{n_2}}} = \dfrac{{{c_1}}}{{{c_2}}}$
Where $i$ is the angle of the incidence, $r$ is the angle of the refraction, ${n_1}$ is the refractive index of the initial medium and ${n_2}$ is the refractive index of the final medium. ${c_1}$ is the speed of the light before crossing the medium and ${c_2}$ is the speed of the light after crossing the medium.

Complete step by step answer:
The snell’s law is also called by the name law of refraction and it provides the boundary condition in which the light passes from one medium to the other medium through the boundary. It states that the ratio of the sine of the angle of the incidence to the sine of the angle of the refraction is equal to the ratio of the refractive index of the medium before passing the boundary and the refractive index of the final medium. It can also be equated to the ratio of the speed of the light.

Note:The snell’s law helps in finding the direction of the light after crossing the boundary and it also helps in finding the change in the speed of the light after refraction. This law is also applicable for the negative refraction of the light. When the light travels from the air to the water, its velocity decreases.