What occurs when a wave bends as it passes into a different medium?

When a wave bends as it passes from one medium into another, this phenomenon is known as refraction. This behavior occurs because waves travel at different speeds in different media. For example, light travels slower in water than in air. As the wave enters the new medium, its speed changes, which causes the wave to change direction.

The extent to which the wave bends depends on the angle at which it hits the interface between the two media, as well as the properties of both media, such as their densities and refractive indices. This bending effect is responsible for various optical phenomena, such as the apparent bending of a straw in a glass of water or the formation of rainbows.

Understanding refraction is crucial in many fields, such as optics, acoustics, and various engineering applications. It contrasts with other wave behaviors like reflection, where the wave bounces back into the original medium, diffraction, which involves the spreading of waves around obstacles or through openings, and interference, where waves superpose to form a resultant wave pattern. Each of these phenomena has distinct characteristics and occurs under different circumstances.