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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.
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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