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Question
What does sign of power (+ve or –ve) indicate?
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Solution
Positive power (+ve) of a lens indicates converging ability of a lens as in the case of convex lens, and negative power (−ve) of a lens indicates its diverging ability as in the case of concave lens.
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RELATED QUESTIONS
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Fill in the following blank with suitable word:
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| Column - I | Column - II | ||
| 1 | Retina | a | Path way of light |
| 2 | Pupil | b | Far point comes closer |
| 3 | Ciliary muscles | c | near point moves away |
| 4 | Myopia | d | Screen of the eye |
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