CHAPTER 13 SPHERICAL MIRRORS Location of images from concave mirrors
Using the rules of incident/reflected rays and the concept of real and virtual images, we can now describe the types of images produced by concave mirrors.
We need only show the intersection of two rays to find an image. From rule 4, the part of the object on the principal axis will strike the pole with an angle i = 0°, giving r = 0°. This means it will reflect back along its own path.
In Fig. 13.8, the object is the solid blue arrow, and the corresponding image is the blue dashed arrow. The type and position of the image depends on the placement of the object in front of the mirror.
C
F
C
F
C
F
FIG. 13.8a
Object: • outside C Image: • real • inverted • diminished
FIG. 13.8b
Object: • at C Image: • real • inverted • same size
FIG. 13.8c
Object: • between C and F Image: • real • inverted • magnified
C
F
C
F
FIG. 13.8d
Object: • at F Image: •
FIG. 13.8e rays travel parallel to infinity • no image
Object: • between F and the pole Image: • virtual • upright • magnified
