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Question
A person can read a book clearly only if he holds it at an arm's length from him. Name the defect of vision:
if the person is a young man
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Solution
If the person is a young man, the defect of vision is hypermetropia. Hypermetropia occurs either because the eye lens has low converging power or because the eyeball is too short. This makes the near vision defective.
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Rewrite the following table so as to match second and third column with first column.
|
Column I
|
Column II
|
Column III
|
|
(i) Myopia
|
Old age problem
|
Bifocal lens
|
|
(ii) Presbyopia
|
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|
Concave lens.
|
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