1. Mirrors

2. Mirrors and Images (p 276) Light travels in straight lines, this is the reason shadows and images are produced (p 277) Real images are images that can be projected onto a screen (p283) The law of reflection states: the angle of reflection equals the angle of incidence (p283 add) Mirrors are a practical application of the law of reflection

3. (p 283 add) there are 3 types of mirrors: Plane : Concave : Convex :

4. The law of reflection applies to all types of mirrors as well as rough and smooth surfaces (normal reflection) (add to p 283) On smooth surfaces parallel light rays are reflected parallel from the surface:

5. (add to p 283) On rough surfaces the law of reflection still applies but parallel rays are not reflected from the surface as parallel rays. This is called diffuse reflection:

6. Plane Mirrors (p 287) your image in a plane mirror seems to be as large as you are and just as far behind the mirror as you are in front of it For all mirrors: d i image distance d o object distance h i image height h o object height To locate an image you need to draw 2 rays The image is located where the rays meet

7. For a plane mirror you only need a mirror half the height of an object to see the whole object:

8. Ray diagram for a Plane Mirror (p 288) The image for a plane mirror is: erect same size virtual

9. Curved Mirrors (p 294) There are 2 types of curved mirrors: concave and convex a.concaveb. convex

10. (p 294)When we draw a concave or convex mirror we show the center of curvature (C) The center of curvature is the center of the sphere: A line drawn through the center of the curve and the center of the mirror is called the principle axis

11. (p 294) The focal point is half-way between the center of curvature (C) and the mirror Rays of light drawn parallel to the principle axis reflect from a concave mirror through the focal point Concave mirror converge (bring together) light rays In the same way rays of light parallel to the principle axis will reflect from a convex mirror as if they came from the focal point (p 295) Convex mirrors diverge (spread apart) light rays

12. (p 295) real images can be projected onto a screen, virtual imaged cannot be projected Focal point: Concave:Convex: “f” is positive “f” is negative Focal length: distance between “f” & mirror

13. Spherical Aberration (p 296) Spherical mirrors have a defect called spherical aberration The rays parallel to the principle axis that reflect near the edge of the mirror do not reflect through the focal point To correct this problem the shape of the mirror may be adjusted to a parabolic shape (add) In lenses there is a similar problem called chromatic aberration

14. Diagram of Spherical Aberration

15. Ray Diagrams for Concave Mirrors (p 297) to find the image draw the 2 rays : Parallel (to principle axis) and to or from “f” to or from “f” and parallel (to principle axis)

16. (p 298) a.) Object beyond “C”; image: inverted smaller real

17. Ray Diagram for Concave Mirror, Object outside “C” The image is: inverted, smaller, real

18. b.) Object at “C”; image: inverted same size real

19. c.) Object between “C” & “F”; image: inverted larger real

20. e.) Object between “F” & mirror; image:erect larger virtual

21. Ray Diagram for a Concave Mirror, object between “F” & mirror The image is erect, larger, virtual

22. (p 298)d.) Object at “F”; NO image is produced (p297b) a ray coming from “C” will be reflected back through “C”: Sign Conventions for Mirrors (p 299) Real (in front of mirror) focal points or images: + (“f” & “d i ” are positive) Virtual (behind mirror) focal points or images: - (“f” & “d i ” are negative) Erect images: + “h i ” Inverted: - “h i ”

23. (p 299) Convex Mirror-Virtual Image: the image is always: erect, smaller, virtual

24. Ray Diagram for a Convex Mirror The image is erect, smaller, virtual

25. Mirror Equations (p300) 1 = 1 + 1 f d i d o Magnification M = h i = - d i h o d i See example problems 1 and 2 (p 58, 59) (p301) 1. the + value for d i indicate image is real, all real images are inverted 2. (p302)The - value for di indicate image is real, all real images are inverted

26. Review: Image formed with Flat Mirrors

27. Focal Length Shown by Parallel Rays

28. Image Formed by a Convex Mirror