What are light bends?

Light bends when it moves from one material to another, just like when you slide from a smooth floor to a carpet.

Imagine you're pushing your toy car across the room. It goes fast on the smooth floor, but then it slows down and changes direction when it hits the bumpy carpet. That’s what happens with light: it changes speed and direction when it moves into a new material, like from air to water or from glass to plastic.

Think of light as a group of tiny, fast runners. When they run through air, they're free to move quickly. But if they suddenly have to run through something thicker, like water, they slow down. Since some parts of the light hit the new material first, they slow down before others do. This causes the whole beam of light to change direction, it bends.

You can see this happen when you look at a straw in a glass of water. The straw looks bent even though it's straight, that’s because light bends as it moves from water to air on its way into your eye! Light bends when it moves from one material to another, just like when you slide from a smooth floor to a carpet.

Imagine you're pushing your toy car across the room. It goes fast on the smooth floor, but then it slows down and changes direction when it hits the bumpy carpet. That’s what happens with light: it changes speed and direction when it moves into a new material, like from air to water or from glass to plastic.