P3 Revision - Reflection

-For light moving from gas to air, the angle of refraction gets closer to 90°, as the angle of incidence decreases

-The angle of incidence (i) is at the critical angle (C) when the angle of refraction (r) is at 90°. Light is refreacted along the boundary

-Different materials have different critical angles. Diamond has the lowest at 24°, which is why it reflects so much light.

- Refractive Index = 1 / sin C

  sin C = 1 / n

Endoscopes:

Medical - to transmit pictures of the inside of the body (eg. bronchoscopy/airways, arthroscopy/joints)

Industrial - to transmit pictures of the inside of complex machinery

Lasers - energy source for cutting, cauterising and burning

Communications - to transmit data over long distances without transmission loss (eg. optical fibres)