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A pin is placed 0.1 m in front of a convex lens of focal length 0.2 m and refractive index 1.50. The surface of the lens farther away from the pin is silvered and has a radius of curvature of 0.22 m. How far from the lens is the final image formed ? |
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Answer» Solution :(b) `|(1)/(F)| = (2)/(f_(1))+(1)/(f_(m))=(2)/(20)+(2)/(22)` `therefore "" |F| = (110)/(21) cm` The convex lens with a silvered surface behaves as a concave mirror of effective focal length. `therefore "" F = (-100 cm)/(21)` and mu = - 10 cm By mirror formula, `(1)/(v) + (1)/(u) = (1)/(F)` `rArr "" (1)/(v) = - (21)/(110) + (1)/(10)` v = - 11 cm. |
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