What occurs during the phenomenon of refraction?

Refraction occurs when light passes from one medium to another, resulting in a change in speed, which causes the light to bend. This bending of light is dictated by the refractive indices of the two media involved. When light enters a medium with a different density—such as moving from air into water or glass—the change in speed causes the light to change direction. This phenomenon can be observed in everyday situations, such as when a straw appears bent when placed in a glass of water.

In contrast, bouncing off a surface describes reflection, not refraction. Absorption involves light being taken in by a material, leading to energy transformation rather than a change in direction. Lastly, light does not travel at a constant speed through all mediums; its speed varies depending on the optical density of the medium, which is crucial for understanding how refraction works. Thus, the correct understanding of how light behaves between different media is essential, highlighting the bending aspect of refraction as a fundamental concept in optics.