refraktiossa

Refraction is the change in direction of a wave passing from one medium to another or from a gradual change in the medium. It is most commonly observed when light or sound waves travel across the interface between two different media, such as air and water, or glass and air. The amount of refraction depends on the indices of refraction of the two media, which are measures of how much the speed of light is reduced when it enters a medium.

In optics, refraction is described by Snell's Law, which states that the ratio of the sines of the angles of incidence and refraction is equal to the ratio of the indices of refraction of the two media. This law can be expressed mathematically as:

n1 * sin(θ1) = n2 * sin(θ2)

where n1 and n2 are the indices of refraction of the first and second media, respectively, and θ1 and θ2 are the angles of incidence and refraction, respectively.

Refraction is responsible for many everyday phenomena, such as the apparent bending of a straw in a glass of water, the formation of rainbows, and the focusing of light by lenses. It is also a crucial principle in the design of optical instruments, such as cameras, telescopes, and microscopes. In addition to light, refraction can also occur with other types of waves, such as sound and water waves, although the principles are generally the same.