Which phenomenon is responsible for the bending of light rays when they pass from air into water?

The phenomenon responsible for the bending of light rays when they transition from air into water is refraction. Refraction occurs because light travels at different speeds in different media. When light enters water from air, it slows down due to the higher density of water compared to air. This change in speed causes the light rays to bend at the interface between air and water, following Snell's law, which relates the angle of incidence to the angle of refraction based on the refractive indices of the two media.

In the case of air and water, the light rays bend towards the normal line (an imaginary line perpendicular to the surface) as they move into the water. This bending effect is crucial for various optical applications, including the design of lenses and understanding natural phenomena like the visual distortion of objects submerged in water.

Understanding refraction is essential in optics because it helps explain how lenses focus light, how we perceive images in water, and the behavior of light as it passes through various mediums.