1. Properties of Curved Mirrors

2. Properties of the Image (MALT)
MAGNIFICATION (M)
M=hi ÷ ho
ATTITUDE (A)
Upright or inverted
LOCATION (L)
Distance from mirror
In front of mirror or behind mirror
TYPE (T)
Real or virtual

3. CURVED MIRRORS Concave (Converging) Convex (Diverging)
Reflective surface CURVES AWAY from object
“go INTO a CAVE”
Convex (Diverging)
Reflective surface CURVES TOWARD object
“to VEX is to FLEX”

4. Concave mirror

5. Convex mirror

6. Concave Mirror
The centre of curvature, C, of a concave mirror is on the reflective side (“in front”) of the mirror.
Focal point, F, is also on the reflective side of the mirror, half way between C and the surface of the mirror.
The focal length, f, is half of the radius. R = 2f
The vertex, V, is the point on the mirror which is on the principal axis

7. Significance of the focal point
All incident light rays that are parallel to the principal axis will strike the reflective surface and reflect through the focal point
All incident light rays that pass through the focal point will strike the reflective surface and reflect parallel to the principal axis

8. Finding the Image made by a concave mirror
Step 1
Step 2
Step 3
Step 4

10. 4 useful rays for curved mirrors

11. Image characteristics for an object outside of the center of a concave mirror
M: The image is smaller!
A: the image is inverted, in the sense that the direction of the arrow has been changed
L: the image is in front of the mirror (same side of the mirror as the object) and located between C and F
T: the image is real (in front of the mirror)

12. Image from a concave mirror: case 1

13. Animation for case 1

14. Image for a concave mirror: case 2

15. If the object is in between the center and the focal point, the image is
Real
Inverted
Magnified in the sense that the image is bigger than the real object.
The direction of the light rays can be reversed and the result is still physically possible! (or the image and object interchanged)

16. Animation for case 2

17. Image from a concave mirror: case 3

18. Image from a concave mirror: case 3

19. Animation for case 3

20. Properties of the image
If the object is closer to the mirror than the focal point F, the image is
Virtual, it is behind the mirror
Upright, not inverted
Magnified
Can be used for shaving!

21. Concave (Converging) Mirror Worksheet

23. Page 421

24. Summary for Concave Mirror

25. Java Applet

26. Convex (Diverging) Mirror
Always produces the same kind of image, regardless of the location of the object!
Image Characteristics
Magnification
Smaller
Attitude
Upright
Location
Closer to & behind mirror
Type
virtual

27. CURVED MIRRORS Concave (Converging) Convex (Diverging)
Reflective surface CURVES AWAY from object
“go INTO a CAVE”
Convex (Diverging)
Reflective surface CURVES TOWARD object
“to VEX is to FLEX”

28. Concave mirror

29. Applications of a concave mirror
If a point source of light is located at F, then all rays will be reflected back parallel to the principal axis of mirror producing a parallel beam!
Applications: flashlight, car headlights
Conversely, incoming parallel rays will all be reflected through F. So all light energy is focused to one point!
Applications: reflecting telescope, solar cooker

30. CONCAVE APPLICATIONS

31. Solar Cooker

32. Parabolic Solar Collectors
Can be used to generate electricity

33. Makeup Mirror

34. Light bulb mirage

36. How it works

37. Piggy Mirage

38. Convex mirror

39. CONVEX APPLICATIONS