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Physics

Refraction of Light

Quick fact

Refraction can make objects appear displaced, split white light into a rainbow, and even allow light to travel along curved paths in fiber-optic cables—all because light changes speed when crossing between transparent substances.

Why this is interesting

Have you ever noticed a straw in a glass of water appearing to bend or break? This isn’t an illusion—it’s a clue to how light moves through different materials.