Activity 9.6

Activity . Observe the image of a distant object, say a distant tree, in a plane mirror. Could you see a full-length image? Table . 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 Try with plane mirrors of different sizes. Did you see the entire object in the image? Repeat this Activity with a concave mirror. Did the mirror show full length image of the object? Now try using a convex mirror. Did you succeed? Explain your observations with reason. You can see a full-length image of a tall building/tree in a small convex mirror. One such mirror is fitted in a wall of Agra Fort facing Taj Mahal. If you visit the Agra Fort, try to observe the full image of Taj Mahal. To view distinctly, you should stand suitably at the terrace adjoining the wall. Uses of convex mirrors Convex mirrors are commonly used as rear-view (wing) mirrors in vehicles. These mirrors are fitted on the sides of the vehicle, enabling the driver to see traffic behind him/her to facilitate safe driving. Convex mirrors are preferred because they always give an erect, though diminished, image. Also, they have a wider field of view as they are curved outwards. Thus, convex mirrors enable the driver to view much larger area than would be possible with a plane mirror.