Light changes speed and direction due to different optical densities in media, causing refraction—a phenomenon explained by Snell's Law.
When light transitions from one medium to another with a different optical density, it undergoes a phenomenon called refraction.
The speed of light is different in each medium because of the varying interactions between photons and atoms.
According to Snell's Law, the angle of incidence and the angle of refraction are related by the refractive indices of the two media.
As light passes from a less dense medium (lower refractive index) to a denser one (higher refractive index), it slows down and bends toward the normal—an imaginary line perpendicular to the surface at the point of incidence.
Conversely, when light moves from a denser medium to a less dense one, it speeds up and bends away from the normal.
This change in speed and direction is fundamental to the bending of light rays during refraction.
The refractive index is a measure of how much a medium can slow down light.
Different materials have distinct refractive indices, causing light to refract differently in each substance.
This bending of light is a crucial concept in optics and is utilized in various optical devices like lenses, prisms, and eyeglasses, where manipulating light's path is essential for their functioning.
Question
Why does a ray of light bend when it travels from one medium into another?