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An image of a linear object due to a convex mirror is 1/4 th of the length of the object . If focal length of the mirror is 10 cm , find the distance between the object and the image. The linear object is kept perpedicular to the axis of the mirror. |
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Answer» Solution :Mgnification of image `m = - (v)/(U) = (H.)/(h) = 1/4` `THEREFORE v = - u/4` Here, f = 10 cm ,`m = 1/4` v = ? , u +v = ? Using Gauss LAW `1/f = 1/u + 1/v` `therefore 1/10 = 1/u -(4)/u` `therefore1/10 = - (3)/u` `therefore u = - 30 cm ` Againusing Gauss law , `(1)/(v) = 1/f - (1)/(u) = (1)/(10) + (1)/(30)` `thereforev = 30/4 = 7.5 cm` `therefore ` Distance between object and image ` h = u + v = | - 30 | + 7.5` `thereforeu + v = 37.5 cm ` |
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