Refractive Index

MyGCSE Science Video about Refractive Index

http://www.my-gcsescience.com

Specification reference:
P3.1.3 Lenses

• Refraction is the change of direction of light as it passes from one medium to another.
• A lens forms an image by refracting light
• refractive index =  sin i /sin r, where i is the angle of incidence and r is the angle of refraction

P3.1.4 The Eye

• The focal length of a lens is determined by:
•  the refractive index of the material from which the lens is made, and
•  the curvature of the two surfaces of the lens
• For a given focal length, the greater the refractive index, the flatter the lens. This means that the lens can be manufactured thinner.