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An object of length 10cm is placed at right angles to the principal axis of a mirror of radius of curvature 60 cm such that its image is virtual, erect and has a length 6 cm. What kind of mirror is it and also determine the position of the object? |
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Answer» Solution :Since the image is virtual, erect and of a SMALLER size, the given mirror is ` (##AKS_ELT_AI_PHY_XII_V02_C_C02_SLV_006_S01.png" width="80%"> convex.(concave mirror does not form an image with the said description). Given`R= +60cmf= (R )/( 2) =30cm` Transverse magnification, ` m=(1)/(O)= (6)/(10) =+ (3)/(5 ) ` further`m=-(v)/(U )= 3/5` `thereforev= ( 3u )/(5)` USING`(1)/(v )+ (1 )/(u ) = (1)/(f)""(-5)/(3u ) +(1)/(u )= (1)/(30)` `(-5+3)/( 3u) = (1)/(30)thereforeu=- 20 cm ` Thus the object is at a distance 20 cm (from the pole) in front of the mirror. |
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