Question

the angle between a refracted ray and the normal drawn at the point of incidence to the interface at which refraction occurs.

Answer 1

Angle of refraction

Explanation:

The angle between a refracted ray and the normal at the point of incidence to the interface at which refraction occurs , is called the angle of refraction.

It is denoted by $\displaystyle \mathbf {\theta}$

It is also called the angle of transmission.

By Snell's law,

           $\displaystyle \frac{n_1}{n_2} = \frac{sin\theta_2}{sin\theta_1}$

where,

        $n_1 = index of refraction of first medium\\n_2 = ndex of refraction of second medium\\\theta_1 = angle of incidence\\\theta_2 = angle of refraction$