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www.GOALias.blogspot.com15.4 P15.4 PLAYINGWITH SPHERICALMIRRORSPaheli and Boojho were waiting for theirdinner. Boojho lifted a stainless steelplate and saw his image in it. Oh! Thisplate acts as a plane mirror. My imageis erect and is of the same size. Pahelisaw her image using the back of a steelspoon. “Boojho look here! I can also seemy erect image though it is smaller insize. This spoon also acts as a mirror ofsome kind”, said Paheli.You can also use a spoon or anycurved shining surface to see yourimage.Activity 15.5Take a stainless steel spoon. Bring theouter side of the spoon near your faceand look into it. Do you see your imagein it (Fig. 15.10)? Is this image differentfrom what you see in a plane mirror? Isthis image erect? Is the size of the imagethe same, smaller or larger?Now look at your image using theinner side of the spoon. This time youmay find that your image is erect andlarger in size. If you increase the distanceof the spoon from your face, you maysee your image inverted (Fig. 15.11). Youcan also compare the image of your penor pencil instead of your face.Fig. 15.11 Image from the inner side of a spoonThe curved shining surface of aspoon acts as a mirror. The mostcommon example of a curved mirror isa spherical mirror.If the reflecting surface of a sphericalmirror is concave, it is called a concavemirror. If the reflecting surface is convex,then it is a convex mirror (Fig. 15.12).(a)(b)Fig. 15.10 Image from the outer side of a spoonFig. 15.12 A concave and a convex mirror179LIGHT179