Answer:
Angle of refraction
Step-by-step explanation:
The angle θ2 represents the angle of refraction.
Refraction is the change in direction of light rays as it passes from one medium to another. As light rays passes from one medium to another, it changes direction.
If the incident light is passing from the less dense medium to denser medium, the refracted ray will bend towards the normal. In this case the angle of refraction 'r' is always less than the angle if incidence. (According to the diagram)
Similarly, If the incident light is passing from the denser medium to less dense medium, the refracted ray will bend away from the normal. In this case the angle of refraction 'r' is always greater than the angle of incidence.