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प्रश्न
Observer the following diagram and answer the questions.
a) Which eye defect is shown in this diagram?
b) What are the possible reasons for this eye defect?
c) How this defect is corrected, write it in brief?
उत्तर
a) Myopia or Nearsightedness
b) Possible reasons of defect
i. The curvature of the cornea and the eye lens increases. The muscles near the lens cannot relax so that the converging power of the lens remains large.
ii. The eyeball elongates so that the distance between the lens and the retina increases
c) correction of defect: this defect can be corrected using spectacles with concave lens. This lens diverges the incident rays and these diverged rays can be converged by the lens in the eye to form image on the retina.
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(b) short-sight
(c) hind-sight
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Name the parts labeled 1 to 4.
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|
Column I
|
Column II
|
Column III
|
|
(i) Myopia
|
Old age problem
|
Bifocal lens
|
|
(ii) Presbyopia
|
Nearsightedness
|
Concave lens.
|
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 |
- Name the defect shown in the diagram.
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