1. Refraction

2. Learning goals We are learning why light bends.
We are learning to calculate the index of refraction.

3. terms
Medium: the substance or material that light is travelling through
Refraction: the change in direction of light when it crosses a boundary between two media
Refracted Ray: the ray after crossing a boundary between two media
Angle of Refraction: the angle between the refracted ray and the normal

4. refraction
When light enters a new medium it changes speed

5. Cause of refraction
Light will bend towards the normal when its speed decreases
Light will bend away from the normal when its speed increases

6. Apparent depth
The depth an object appears to be at due to refraction of light in a transparent medium

7. Total internal reflection
The reflection of all the incident light off the boundary
Only when going from more dense to less dense mediums

8. The critical angle
TIR: when the angle of incidence is greater than the critical angle
The critical angle is the angle where the light refracts along the boundary

9. Water demo!!!

10. TIR Examples

11. Learning goals We are learning why light bends.
We are learning to calculate the index of refraction.