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प्रश्न
A person needs a lens of power –4.5 D for correction of her vision.
- What kind of defect in vision is she suffering from?
- What is the focal length of the corrective lens?
- What is the nature of the corrective lens?
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उत्तर
- The negative power of the lens suggests that she must be suffering from myopia.
- Power, P = ─4.5 D, focal length, f = ?
Now, P = 1/ f
⟹ f = 1/ P = 1/ −4.5 = −0.222 m = − 22.2 cm - Myopia is corrected using a concave or divergent lens.
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संबंधित प्रश्न
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Explain the terms ‘adaptation’ and ‘accommodation’ with reference to the eye.
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Given alongside is a diagram depicting a defect of the human eye. Study the same and then answer the questions that follow:
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Differentiate between:
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Draw a neat labeled diagram to show how hypermetropia can be rectified.
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