What is the effect of a wave passing from a less dense medium to a more dense medium?

When a wave travels from a less dense medium, such as air, to a more dense medium, like water or glass, two key effects occur: the wave slows down and changes direction or bends. This phenomenon is known as refraction.

The speed of a wave is influenced by the medium through which it travels. In a more dense medium, the molecules are packed closer together, which affects the wave's propagation. This results in a decrease in wave speed as it enters the more dense medium. According to Snell's Law, as the wave slows down, it also bends towards the normal, which is the line perpendicular to the boundary between the two media.

This combination of slowing down and bending is important in various applications, including optics, where it explains how lenses work. Understanding this behavior helps in predicting how waves interact with different materials and is fundamental to studying wave mechanics.