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Per NCERT, a combination of two lenses of power +2.0 D and +0.25 D in contact is equivalent to a SINGLE lens of power what?
A+2.25 D (= sum of individual powers)
B+1.0 D
C+0.50 D (= product)
D+1.75 D (= difference)
Answer & Solution
Correct answer: A. +2.25 D (= sum of individual powers)
Per NCERT §9.3.8 example, +2.0 + 0.25 = +2.25 D. Optician's algebra during eye testing.
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