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Question
With the help of a ray diagram, show how a compound microscope forms a magnified image of a tiny object, at least distance of distinct vision. Hence derive an expression for the magnification produced by it.
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Solution
Image formation by compound microscope at the least distance of distinct vision:
Expression for magnification:
For objective,
Magnification = mo = `"P'Q'"/"PQ" = (-"v")/"u"`
When the image is formed at the least distance of distinct vision, then
Magnification = me = `(1 + "D")/"f"_"e"`
So, final magnification = m = mo × me = `"v"/"u" (1 + "D"/"f"_"e")`
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