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www.GOALias.blogspot.comFig. 15.3 Reflection of objects in waterat a lighted candle first througha straight pipe and then througha bent pipe (Fig. 15.2). Why wasBoojho not able to see the candleflame through a bent pipe?This activity showed thatlight travels along straight lines.How can we change the pathof light? Do you know, whathappens when light falls on apolished or a shiny surface?15.2 REFLECTIONOF LIGHTOne way to change the directionof light is to let it fall on a shinysurface. For example, a shiningstainless steel plate or a shiningsteel spoon can change thedirection of light. The surface ofwater can also act like a mirrorand change the path of light.Have you ever seen the reflectionof trees or buildings in water(Fig. 15.3)?Any polished or a shiny surface canact as a mirror. What happens whenlight falls on a mirror?You have learnt in Class VI that amirror changes the direction of light thatfalls on it. This change of direction by amirror is called reflection of light. Canyou recall the activity in which you gotthe light of a torch reflected from amirror? Let us perform a similar activity.Activity 15.1Take a torch. Cover its glass with a chartpaper which has three slits as shown inFig. 15.5. Spread a sheet of chart paperPaheli remembers the story of the lion and therabbit from the Panchtantra, in which therabbit fooled the lion by showing him hisreflection in water (Fig. 15.4).Fig. 15.4 Reflection of the lion in water175LIGHT175