Page 146 - NCERT Science Class 10 English Medium

Activity 9.59.5
Activity 9.5
Activity
Activity
9.5
Activity 9.5
n Take a convex mirror. Hold it in one hand.
n Hold a pencil in the upright position in the other hand.
n Observe the image of the pencil in the mirror. Is the image erect or
inverted? Is it diminished or enlarged?
n Move the pencil away from the mirror slowly. Does the image
become smaller or larger?
n Repeat this Activity carefully. State whether the image will move
closer to or farther away from the focus as the object is moved
away from the mirror?

We consider two positions of the object for studying the image formed
by a convex mirror. First is when the object is at infinity and the second
position is when the object is at a finite distance from the mirror. The ray
diagrams for the formation of image by a convex mirror for these two
positions of the object are shown in Fig.9.8 (a) and (b), respectively. The
results are summarised in Table 9.2.

Figure 9.8 Formation of image by a convex mirror
Figure 9.8
Figure 9.8
Figure 9.8
Figure 9.8
Table 9.2 Nature, position and relative size of the image formed by a convex mirror
Position of the Position of the Size of the Nature of the
object image image image
At infinity At the focus F, Highly diminished, Virtual and erect
behind the mirror point-sized

Between infinity Between P and F, Diminished Virtual and erect
and the pole P of behind the mirror
the mirror
You have so far studied the image formation by a plane mirror, a
concave mirror and a convex mirror. Which of these mirrors will give the
full image of a large object? Let us explore through an Activity.
9.6
Activity 9.6
Activity 9.69.6
Activity
Activity 9.6
Activity
n Observe the image of a distant object, say a distant tree, in a
plane mirror.
n Could you see a full-length image?

Light – Reflection and Refraction 141

2024-25