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An astrnomical telescope having angular magnification 5 consists of two thin lenses 24cm apart. Find the power of it's lenses. |
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Answer» magnifying POWER = 5 2 thin LENSES = 24 cm apart fο + fe = 24 to find = focal length. solution = here we consider the fο and fe as a focal length of objects. fο + fe = 24cm (.1) M = fο / fe = 5 fο = 5 fe (2) fe = 24cm / 6 = 4cm ___ from the above 2 equations fο= 5fe = 5(4cm) = 20cm the focal length of the lens is 20cm |
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