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a. At what distance should the lens be ...

a. At what distance should the lens be held in Exercise 27 in order to view the squares distinectly with the maximum possible magnifying power ?

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a. V = - 25 cm, f = 10 cm
`(1)/(v) - (1)/(u) = (1)/(f), (1)/(-25) - (1)/(u) = (1)/(10) `
Solving `rArr u = (-50)/(7) = - 7.14 ` cm
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