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Question
Find the power of a convex lens of focal length of + 25 cm.
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Solution
Given: Focal length (f) = 25 cm = 0.25 m
To find: Power of the lens (P)
Formula: P = `1/("f"("m"))`
Calculation: From formula, P = `1/0.25` = 4 D
The power of the convex lens is 4 D.
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