Refraction

Real World Example

Imagine you're walking briskly on a sidewalk and suddenly step onto a sandy beach, causing your pace to slow down and your path to veer slightly. This change in direction and speed as you transition from pavement to sand is similar to how light bends, or refracts, when it moves from air into water. Just as your feet adjust to the new terrain, causing you to change direction, light changes speed and direction when it moves from one medium to another—like from air into water—because each medium has different properties, much like the sidewalk and sand.