Light – Reflection and Refraction PDF

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...

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 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. Activity 9.6 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