Refraction
Physics: Edexcel IGCSE, topic 3.2.3
Refraction of Light
Light is refracted when it travels from one medium to another and changes speed.
Optically dense materials
- If light slows down as it enters a new medium, this medium is “more optically dense”.
- When light enters a more optically dense medium, it is refracted closer to the normal.
- This means that the angle of refraction is smaller than the angle of incidence.
Less optically dense materials
- If light speeds up on entering a new medium, this medium is “less optically dense”.
- The light is refracted further from the normal - the angle of refraction is larger than the angle of incidence.
Test yourself on Refraction
What happens to the angle of refraction when light enters a less optically dense medium and speeds up?