Chapter 23 Light

1. Chapter 23 Light

2. 23.1 Ray Model of Light • Light travels in straight lines • Ray model of light - light travels in straight line paths called rays • geometric optics - straight line rays reflect at various angles • light can be absorbed, reflected or pass through objects Chapter 23

3. 23.2 Reflection • Light reflected off object • angle of incidence • angle of reflection • Law of Reflection • angle of incidence equals the angle of reflection Chapter 23

4. diffuse reflection - light reflected in many directions due to rough surface • plane mirror page 686 fig 23-6 • virtual image - brain interprets any rays entering eye as following a straight line path • image distance = object distance • Example 23.1 mirror • Example 23.2 photo Chapter 23

5. 23.3 Spherical mirrors • convex - reflecting surface on outer surface of sphere demagnified - wide field of view • concave - reflecting surface in inner surface of sphere - magnified image • focal point - rays from a concave mirror meet at a single point Chapter 23

6. figure 23-13 principle axis beyond focal point - image inverted • focal length - distance between focus and center of mirror • convex mirror - focal point is at F behind mirror • figure 23-17 Chapter 23

7. 23.5 Refraction : Snell’s Law • Light passing from one medium to another • figure 23-18 • ex. 23-8 refraction through flat glass • ex. 23-9 depth of pool Chapter 23

8. 23.6 Fiber Optics • total internal reflection • glass and plastic fibers as thin as a few micrometers • light can be transmitted along it with almost no losses • fiber optic cables - telecommunications & medicine • modulated light beam - transmitted at a higher rate and with less loss and interference than an electrical signal Chapter 23

9. Chapter 23