1. OPTICS PROJECT 5% of your mark Due next week Friday
Option of doing either one of the following:
Making a 3D model
Making a brochure

2. 10.3 Images in Concave Mirrors
(Page 419)
How does a concave mirror change the size, shape, and orientation of objects reflected in it?
Copyright © 2010 McGraw-Hill Ryerson Ltd.

3. What is a concave mirror?
A.K.A. “Converging mirror”
Causes light rays to meet at a single point in front of the mirror

4. Properties of Concave Mirrors
(Page 420)
A concave mirror has reflecting surfaces that curve inward (like a cave)
Vocabulary terms that will help you understand how concave mirrors work:
The principal axis is the line that passes through the centre of curvature (C) of the mirror and is normal to the centre of the mirror.
The focal point (F) is the point on the central axis through which reflected rays pass when the incident rays are parallel to and near the principal axis.
The focal length (f) is the distance between the vertex (V) of a mirror and the focal point.
The vertex (V) is the middle point of a curved mirror
The centre of curvature (C) is located at 2X the focal
length (f) on the principal axis.
**Note: All incident rays that pass through the centre
of curvature will reflect back on themselves
Copyright © 2010 McGraw-Hill Ryerson Ltd.

5. If it helps, think of this: Concave mirror = many small flat mirrors side by side
Focal point

6. Concave Mirror Ray Diagrams
It is vitally important that you use a ruler or the straight side of your protractor to draw STRAIGHT lines
Textbook reference:
Page

7. Concave Mirror Reflections
5 Cases for location of OBJECT (not image!)
Object is greater than 2 focal lengths from the mirror (do>2f) – note: 2f = C
Object is at 2 focal lengths/Centre of Curvature (2f/C)
Object is between 1 and 2 focal lengths from the mirror (f<do<2f)
Object is at the focal point (do=f)
Object is between the mirror and the focal point (V<do<f)

8. Case 1: Object beyond 2f/C
Location
Orientation
Size
Type
F<di<2F
Inverted
Reduced
Real

9. Case 2: Object at 2f/C At C Inverted Same Real Location Orientation
Size
Type
At C
Inverted
Same
Real

10. Case 3: Object between 2f and F
Location
Orientation
Size
Type
di>C
Inverted
Enlarged
Real

11. Case 4: Object at F
Location
Orientation
Size
Type
No Image Formed!

12. Case 5: Object between F and V
Location
Orientation
Size
Type
Opposite side of mirror
Upright
Enlarged
Virtual

13. Ray Diagrams for Concave Mirrors (object between F and the mirror)
(Page 422)
Copyright © 2010 McGraw-Hill Ryerson Ltd.

14. Ray Diagrams for Concave Mirrors (object between F and the mirror)
(Page 422)
Copyright © 2010 McGraw-Hill Ryerson Ltd.

15. Ray Diagrams for Concave Mirrors (object between F and C]
(Page 423)
A real image is an image that is formed when reflected rays meet.
Copyright © 2010 McGraw-Hill Ryerson Ltd.

16. Ray Diagrams for Concave Mirrors (object between F and C)
(Page 423)
Copyright © 2010 McGraw-Hill Ryerson Ltd.

17. Ray Diagrams for Concave Mirrors (object beyond C]
(Page 424)
Copyright © 2010 McGraw-Hill Ryerson Ltd.

18. Ray Diagrams for Concave Mirrors (object beyond C)
(Page 424)
Copyright © 2010 McGraw-Hill Ryerson Ltd.

19. HOMEWORK
Page 425 # 1 - 4
Page 430 # 1, 2, 4, 8