1. Curved Mirrors

2. Curved Mirrors Terminology center of curvature - C; the center of the
original sphere
radius of curvature - r;
distance from center of curvature to the mirror
vertex - V; the center of the mirror

3. principal axis - a line through C and V
principal focus - F; the point on the
principal axis where light rays parallel
and close to the principal axis converge;
or from where they appear to diverge
focal length - f; distance from V to F

4. Ray Diagrams Concave (Converging) Mirrors
rays parallel to the principal
axis reflect through the focus
2. rays passing through the focus reflect
parallel to the principal axis
C F

5. Convex (Diverging) Mirrors
1. rays parallel and close to the principal
axis reflect away from the focus
2. rays heading toward the principal focus
reflect parallel to the principal axis
F C

6. Click here to view these three rays that are important in the formation of images in concave (converging) and convex (diverging) mirrors.
Also view reflection
from curved mirrors
here, here,and here.

7. di/do = hi/ho 1/f = 1/do + 1/di Mirror Equation Magnification
Diverging rays must be extended as dotted lines
behind the mirror in order to locate some images.
Mirror Equation
Magnification
di/do = hi/ho
1/f = 1/do + 1/di
f = focal length; positive for converging
mirrors, negative for diverging mirrors
do = object distance; usually positive
di = image distance; can be positive or negative
ho = object height
hi = image height

8. Images formed by concave (converging) mirrors may be:
1. real, virtual, or non-existent
2. upright or inverted
3. reduced, enlarged, or same size
4. in front or behind the mirror
Learn more about concave mirror images here.
The image properties depend on the
object’s location with respect to the
mirror, focus, and center of curvature.

9. Learn more about characteristics of convex mirror images here.
Images formed by convex (diverging) mirrors
are always:
1. virtual
2. upright
3. reduced
4. located behind the mirror between the
vertex and focus

10. General Image Trends Real Images Virtual images Inverted
Front of mirror
positive image distance
Virtual images
always upright
behind the mirror
negative image distance