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Question
A thin converging lens of focal length 5cm is used as a simple microscope. Calculate its magnifying power when image formed lies at:
- Infinity.
- Least distance of distinct vision (D = 25 cm).
Solution
(a) At infinity,
M = `"D"/"f"`
M = `(25 "cm")/(5 "cm")`
M = 5
(b) At least distance of distinct vision
M = 1 + `"D"/"f"`
M = 1 + 5
M = 6
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