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प्रश्न
Name the physical quantity whose unit is dioptre.
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उत्तर
The power of a lens is a physical quantity with dioptre as it's unit.
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संबंधित प्रश्न
What is meant by a power of a lens? Define its SI unit.
Find the focal length of a lens of power −2.0 D. What type of lens is this?
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Give the usual name for the following:
A point inside a lens through which the light passes undeviated.
Which of the two has a greater power: a lens of short focal length or a lens of large focal length?
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Answer the following questions from the given information:
- Identify the type of lenses used in her spectacle.
- Identify the defect of vision Surabhi is suffering from.
- Find the focal length of the lenses used in her spectacle.
If there is a convex lens of focal length 75 cm and a concave lens of focal length 40 cm, then calculate their combined power and combined focal length.
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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 |
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Show the formation of the image by the sphere.
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