The document discusses image formation using convex mirrors. It notes that convex mirrors always produce virtual, upright images that are located behind the mirror and are smaller than the object. As the object distance decreases, both the image distance and size increase. So as an object approaches a convex mirror, its virtual image also approaches the mirror and becomes larger. Additionally, the relationship between object and image distances is such that the distance between the image and mirror is always less than between the object and mirror for convex mirrors.

1. IMAGE
FORMATION
BY CONVEX
MIRRORD R . S A N I A A S L A M O D
L E C T U R E R O P TO M E T R Y K F U E I T

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3. THE DIAGRAMS ABOVE SHOW THAT
IN EACH CASE, THE IMAGE IS
located behind the convex mirror
a virtual image
an upright image
reduced in size (i.e., smaller than the object)
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4. Unlike concave mirrors, convex mirrors always produce
images that share these characteristics. The location of the
object does not affect the characteristics of the image. As
such, the characteristics of the images formed by convex
mirrors are easily predictable
Another characteristic of the images of objects formed by
convex mirrors pertains to how a variation in object
distance affects the image distance and size. The diagram
below shows seven different object locations (drawn and
labeled in red) and their corresponding image locations
(drawn and labeled in blue).
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6. The diagram shows that as the object distance is
decreased, the image distance is decreased and the image
size is increased. So as an object approaches the mirror, its
virtual image on the opposite side of the mirror
approaches the mirror as well; and at the same time, the
image is becoming larger.
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7. IMAGE FORMED BY CONCAVE MIRROR
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8. IMAGE FORMED BY CONVEX MIRROR
The image of an object kept in front of the mirror is formed
behind the mirror.
It is smaller than the object , erect and virtual.
The distance between the image and the mirror is less than
between the object and the mirror.
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9. BEHAVIOUR OF IMAGES IN RELATION TO
POSITION OF THE OBJECT
• The image formed by
CONVEX and PLANE mirrors
are virtual
• The image formed by
CONCAVE mirrors can be real
or virtual
The distance between mirror and the image is least in CONVEX mirror, most
in CONCAVE mirror and equal in PLANE mirror
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