Book 7, Question 122
Why Does Glass Make Light Bend?
Look through a glass of water, and a straw can seem broken or bent! Light slows down when it travels into glass or water. That change in speed bends its path, and that is why glass makes light bend!
More fun facts
- Light travels slower in air than in empty space, and even slower in water.
- When light bends as it passes from one material into another, it's called refraction.
- Different colors of light slow down by different amounts, so they bend at different angles.
- When you look at a friend through a window, the light from their face has been bent by the glass.
- A rule called Snell's law describes exactly how much light bends.
- You can measure the speed of light in gelatin with a laser pointer, using how much the beam bends.
Sources: NASA Science, Science News Explores
Questions kids ask
What is refraction?
Light bending as it passes from one material into another.
Does light travel slower in water?
Yes. It travels slower in water than in air.