1. Reflection and Mirrors

2. Law of Reflection  i  r

3. Hero of Alexandria "Principle of least distance" How does a ray "know" which path to follow? AB AB All “incorrect” paths are longer!!

4. Flat Mirrors “Ray Tracing”

5. What size mirror do you need?

6. Question: Does your distance matter?

7. Some Physics of Metals Metals conduct electricity because electrons can move around. Electrons re-arrange themselves to prevent a light wave from entering the surface of the metal. In non-conducting materials, electrons are tied to a positive charge and are not free to roam through the material.

8. Reflectivity of Metals

9. Why the Different Colors? Silver - essentially all colors are reflected Gold - does not reflect blue; reflected light looks reddish-yellow Copper - does not reflect blue or green; reflected light looks reddish in color

10. How are Radio Waves Similar?

11. Spherical Mirrors Shaving/makeup mirrors Telescopes Car side-view mirrors Spoons, pots, etc.

12. Spherical Mirrors C F - focus of mirror F C – center of curvature

13. Image Formation-Concave Mirror reflects to the left C F O Ray through the focus reflects parallel to the axis Incoming ray parallel to axis reflects through the focus Image

14. Image Formation-Concave C F O As the object gets farther away, the image appears closer to the focus.

15. Image Formation-Concave C F I O If the object is inside the focal point, The image will be virtual and upright.

16. Image Formation-Convex C F O (truck appears far away) Mack truck Demagnified image,