Question

can anybody explain retraction of light.

Answer 1

The refraction of light when it passes from a fast medium to a slow medium bends the light ray toward the normal to the boundary between the two media. ... Refraction is responsible for image formation by lenses and the eye. As the speed of light is reduced in the slower medium, the wavelength is shortened proportionately.

Answer 2

DescriptionIn physics, refraction is the change in direction of a wave passing from one medium to another or from a gradual change in the medium. Refraction of light is the most commonly observed phenomenon, but other waves such as sound waves and water waves also experience refraction