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प्रश्न
Power of a lens is – 4D, then its focal length is
विकल्प
4m
–40m
–0.25 m
–2.5 m
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उत्तर
– 0.25 m
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संबंधित प्रश्न
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Match the following:
| 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 |
| 5 | Hypermetropia | e | Power of accommodation |
