Refraction

Science

Definition

Refraction is the bending of a wave as it passes from one medium to another due to a change in speed. Light slows down when entering a denser medium and bends toward the normal; it speeds up and bends away from the normal when entering a less dense medium.

Examples

  • A straw appearing bent when placed in a glass of water
  • A prism splitting white light into a rainbow of colors
  • Mirages on hot roads caused by light bending through layers of air at different temperatures
Key Fact

Snell's law: n₁sinθ₁ = n₂sinθ₂

Related Terms

Reflection Lenses and mirrors Wave properties Electromagnetic spectrum

Study This Concept

Practice refraction with free review games in these units:

Physics Unit 7: Light and Optics