Practice question
MCQ
Question
A convex lens has a power of \( +5 \, \text{D} \). What is its focal length in centimeters?
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Choose one · Correct answer highlightedExplanation
**Power of lens** P (D) = 1/f (m), +5 D => f=1/5=0.2 m=20 cm. Virtual magnified image by convex lens when object within focal point, u
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