What occurs when light passes from water into air?

When light travels from water into air, it encounters a change in the medium, which affects its speed and direction. The process is governed by the principles of refraction.

As light moves from a denser medium (like water) to a less dense medium (like air), it bends away from the normal line. The normal line is an imaginary line perpendicular to the surface at the point of contact between the two media. This bending away from the normal occurs because light travels faster in air than in water, resulting in a change in direction as it exits the water and enters the air.

Understanding this concept is crucial for anyone studying optics, particularly in applications such as designing lenses or understanding the behavior of light in different environments. The ability to predict how light will behave when transitioning between different media allows for more effective manipulation of light in optical devices. This knowledge is fundamental in the field of optometry and opticianry, where precise control of light is often necessary.