Chapter No. 7. Lenses.
What are the differences between farsightedness and nearsightedness?
Farsightedness
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Nearsightedness
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A person suffering from this defect can see distant object clearly but is unable to see nearby objects.
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A person suffering from this defect can see nearby objects clearly but is unable to see distant objects.
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Diagrammatic representation:
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Diagrammatic representation:
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Image is formed behind the retina.
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Image is formed before the retina.
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The distance between the eye lens and the retina decreases.
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The distance between the eye lens and the retina increases.
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It can be corrected by using spectacles having convex lenses of suitable focal length.
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It can be corrected by using spectacles having concave lenses of suitable focal length.
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