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A plano-convex lens fits exactly into a plano-concave lens. Their surfaces are parallel to each other if the lenses are made of different materials. Will the combination act as a lens? If so, what is its focal length? Is it convergent or divergent ? |
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Answer» Solution :LET R be the radius of curvature `(1)/(f_(1)) = - ((n_(1) - 1))/(R) and "" (1)/(f_(2)) = - ((n_(2) - 1))/(R)` `therefore (1)/(f) = (1)/(f_(1)) + (1)/(f_(2)) = (n_(2) - n_(1))/(R) ne 0"" because n_(2) ne n_(1)` Since F has finite VALUE, The combination ACTS as a LENS, It will be conversent if `n_(2) gt n_(1)` and divergent if `n_(2) lt n_(1)` |
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