Certified Ophthalmic Technician (COT) Practice Test 2026 - Free COT Practice Questions and Study Guide

When a sound wave travels from one medium to another, the phenomenon that occurs is known as refraction. This process involves the bending of the sound wave as it enters a different medium, such as from air into water, which has different physical properties like density and elasticity.

Refraction occurs because the speed of sound varies in different media. For instance, sound travels faster in water than in air. When the wavefronts of the sound travel from air to water, they change speed, causing the direction of the sound wave to bend at the boundary between the two media. This bending of the sound wave results in a change in the angle at which the sound propagates.

Other phenomena related to sound waves, such as interference, occur when multiple sound waves meet and overlap, leading to areas of constructive or destructive interference. Diffraction refers to the bending and spreading of waves around obstacles or through openings, while an echo is the reflection of sound waves off a surface, returning to the listener. Although these processes are significant in the study of sound, they do not pertain to the specific behavior of sound waves transitioning between different media, which is accurately described by refraction.