The document discusses refraction and how light behaves when passing from one medium to another with different densities. It defines refraction as light bending or changing speed due to traveling through different mediums. Snell's law is introduced to relate the angle of incidence and refraction based on the refractive indices of the materials. The critical angle is defined as the angle at which total internal reflection occurs, with the refractive index calculated from it. Homework questions ask about using fiber optics instead of copper wires for communication and drawing a diagram showing how signal intensity changes with distance.

1. A Clear View Glass and Light May 29, 2009

4. Refraction

5. Refraction Refraction is when waves ____ __ or slow down due to travelling in a different _________. A medium is something that waves will travel through. When a ruler is placed in water it looks like this: In this case the light rays are slowed down by the water and are _____, causing the pen to look odd. The two mediums in this example are ______ and _______. Words – speed up, water, air, bent, medium

6. Wave diagrams of Refraction Waves change direction when changing speed Waves are slowed down when entering glass

10. Using the Critical Angle… 1) Ray gets refracted 4) Ray gets internally reflected 3) Ray still gets refracted (just!) 2) Ray still gets refracted THE CRITICAL ANGLE