* Change in Speed: Light travels at different speeds in different mediums. For example, light travels faster in air than in water. When light moves from a faster medium to a slower medium, it slows down. Conversely, it speeds up when moving from a slower to a faster medium.
* Change in Direction: The change in speed causes the light wave to bend, or refract. The angle of refraction depends on the angle of incidence (the angle at which the light strikes the surface) and the indices of refraction of the two mediums. The index of refraction is a measure of how much light slows down in a particular medium.
* Change in Wavelength: The frequency of light remains constant when it moves from one medium to another. However, since the speed changes, the wavelength also changes. The wavelength is inversely proportional to the speed of light.
* Other Phenomena: Refraction can also lead to other phenomena like:
* Total Internal Reflection: When light moves from a denser medium to a less dense medium, at a certain angle of incidence, it can be reflected back into the denser medium.
* Dispersion: Different colors of light have slightly different speeds in a medium. This causes white light to separate into its constituent colors when passing through a prism.
In summary: Light waves change speed and direction when they move from one medium to another. This is due to the change in the medium's index of refraction and results in phenomena like refraction, total internal reflection, and dispersion.
