Refraction explains the bending of light in water or air by showing how light changes speed and direction when it moves between different media.
Why it bends:
- When light passes from one medium to another (like from air to water or water to air), its speed changes.
- This change in speed causes the light to change direction — a phenomenon known as refraction.
How it behaves:
- From air to water (less dense to more dense):
- Light slows down.
- It bends toward the normal (an imaginary line perpendicular to the surface).
- From water to air (more dense to less dense):
- Light speeds up.
- It bends away from the normal.
Real-life examples:
- A straw in a glass of water looks bent or broken at the surface.
- A fish in water appears closer to the surface than it really is.
- Mirages form when light bends due to temperature differences in air layers.
In simple terms, refraction bends light because its speed changes when it enters a different material, helping us understand many everyday optical illusions.