1. Mirrors and Lenses Section 1 Mirrors
A. Light is necessary for eyes to see
1. Light waves spread in all directions from a light.
2. The brain interprets light waves as traveling in a straight line.
B. Plane mirror—flat, smooth mirror
1. Light strikes an object and is reflected off the object to the mirror and then back to the object.
2. Virtual image—no light waves pass through the image

2. Reflection in a Plane Mirror

3. Reflection in a Plane Mirror

4. Brain and Mirror Reflection

5. Virtual Image

6. Mirrors and Lenses C. Concave mirror—mirror surface is curved inward
1. Optical axis—imaginary straight line drawn perpendicular to the center of the mirror’s surface
2. Focal point—point on the optical axis through which parallel light rays are reflected
3. Distance from the mirror center to the focal point is the focal length.
4. Real images—light rays converge to form the image

7. Concave Mirror

8. Real Image

9. Concave Mirror

10. Mirrors and Lenses D. Convex mirror—mirror is curved outward
1. Light rays diverge when they are reflected.
2. Images are virtual, upright, and smaller than the actual object.

11. Convex Mirror Image

12. Convex Mirror Image

13. Convex Mirror Image

14. Convex Mirror Image

15. Mirrors and Lenses Section 2 Lenses
A. Lens—transparent material with a curved surface that refracts light rays
B. Convex lens—thicker in the middle than at the edges
1. When an object is more than two focal lengths from the lens, its image is real, reduced, and inverted.
2. When an object is between one and two focal lengths from the lens, its image is real, enlarged, and inverted.
3. When an object is less than one focal length from the lens, its image is virtual, enlarged, and upright.

16. Mirrors and Lenses Section 2 Lenses
B. Convex lens—thicker in the middle than at the edges

17. Mirrors and Lenses Section 2 Lenses
C. Concave lens—thinner in the middle and thicker at the edges; forms a virtual, upright, reduced image

18. Convex versus Concave Lens

19. Concave Lens Refracts

20. Human Eye

21. Lens of Eye Changes

22. Farsighted Eye

23. Corrected Farsighted Eye

24. Nearsighted Eye

25. Corrected Nearsighted Eye

26. Mirrors and Lenses

27. Mirrors and Lenses

28. Mirrors and Lenses