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Question
the biological/technical terms for the lens of eye losing flexibility resulting in a kind of long-sightedness in middle aged people.
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Solution
The lens of eye losing flexibility resulting in kind of long-sightedness in middle aged people – Presbyopia
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RELATED QUESTIONS
Describe the mechanism of focusing the image of a distant object in your eye when you raise your head after reading a book.
Rewrite the following table so as to match second and third column with first column.
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Column I
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Column II
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Column III
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(i) Myopia
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Old age problem
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Bifocal lens
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(ii) Presbyopia
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Nearsightedness
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Concave lens.
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Give Reason:
When you enter into a dark room from bright because of sunlight, you can not see things for a few seconds.
Draw a neat labeled diagram to show how hypermetropia can be rectified.
Name the following:
The defect of the human eye caused due to the uneven surface of the cornea.
Myopia may arise due to ____________.
Draw ray diagram showing myopic eye.
Correlate the given sequence:
Hypermetropia : Convex lens : ______ : Concave lens
A person is unable to see clearly a poster fixed on a distant wall. He however sees it clearly when standing at a distance of about 2 m from the wall.
- Draw ray diagram to show the formation of image by his eye lens when he is far away from the wall.
- List two possible reasons of this defect of vision.
- Draw ray diagram to show the correction of this defect using appropriate lens.
Observe the following diagram and answer questions following it:
- Identify the defect of vision shown.
- List its two causes.
- Name the type of lens used for the correction of this defect.
