Engineering Board Exam Reviewer · Physics · medium
A lens has a focal length of +25 cm. What is its power?
- +0.04 diopters
- +25 diopters
- −4 diopters
- +4 diopters
Answer
D. +4 diopters
Solution
P = 1/f (m) = 1/0.25 = +4 D.
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