What is a Critical Angle?
The critical angle is defined as the angle of incidence where light, instead of passing into the second medium, refracts along the boundary between two different media.
- As the angle of incidence increases, the angle of refraction also increases until it reaches 90°.
- When light is refracted along the boundary, the angle of refraction is 90°.
- The angle at which the incident ray refracts at an angle of 90 degrees is known as the critical angle, denoted as C.
How to Find Critical Angle of a Light Ray
The critical angle is a key concept in optics, especially when light interacts with boundaries between two dissimilar materials. It determines the exact angle of incidence at which light will refract along the interface between the materials, instead of entering the second medium.
In this article, how to find the critical angle of a light ray, the formula for critical angle, Snell’s law, finding a critical angle, and solve the problem.