Refraction of Light through a Transparent Prism

When light passes through a transparent prism, it is refracted. The refraction of light is due to the change in its speed when it passes from one medium to another.

The Process of Refraction

The process of refraction involves the bending of light as it passes through a medium with a different refractive index. The refractive index is a measure of the speed of light in a medium. When light passes through a prism, it is refracted twice, once when it enters the prism and again when it exits.

Angle of Incidence and Angle of Refraction

The angle at which light enters the prism is called the angle of incidence, and the angle at which it exits is called the angle of refraction. The angle of refraction is dependent on the refractive index of the prism and the angle of incidence.

Dispersion of Light

When white light passes through a prism, it is split into its constituent colors. This is due to the fact that different colors of light have different wavelengths and therefore different speeds in the prism. This phenomenon is called dispersion.

Rainbow Formation

The refraction and dispersion of light through a prism is the same process that creates rainbows. When sunlight passes through raindrops, it is refracted and dispersed, creating the colors of the rainbow.

In conclusion, the refraction of light through a transparent prism involves the bending of light due to the change in its speed when it passes from one medium to another. This process results in the dispersion of light, which is the separation of white light into its constituent colors. The angle of incidence and the refractive index of the prism determine the angle of refraction.

When the ray of light goes from optically rarer medium (air) to optically denser medium (glass) at the first surface, it bends towards the normal. At the second refractive surface, the light ray enters from denser medium (glass) to rarer medium (air). Hence, it bends towards the base of the prism i.e. it bends away from the normal.