National League for Nursing (NLN PAX) Practice Exam

The phenomenon that occurs when waves change direction as they pass from one medium into another is known as refraction. This process is fundamentally related to the change in wave speed as the wave travels from one medium to another, such as from air into water. As the wave enters the new medium, it slows down or speeds up, causing it to bend or change direction.

Refraction can be observed with light waves when they pass from air into water; this bending effect is responsible for the apparent displacement of objects submerged in water. The extent and direction of the bending depend on the indices of refraction of the two media involved.

The other phenomena mentioned do not involve a change in direction due to a change in medium: diffraction involves the bending of waves around obstacles and openings, reflection involves the bouncing back of waves when they hit a barrier, and interference occurs when waves overlap and combine to form a new wave pattern.