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प्रश्न
A young man has to hold a book at arm's length to be able to read it clearly. The defect of vision is:
(a) astigmatism
(b) myopia
(c) presbyopia
(d) hypermetropia
उत्तर
hypermetropia
Hypermetropia is the defect of vision the young man is suffering from, because of which he finds it difficult to see nearby objects.
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संबंधित प्रश्न
Name one defect of vision (or eye) which cannot be corrected by any type of spectacle lenses.
A person cannot see the distant objects clearly (though he can see the nearby objects clearly). He is suffering from the defect of vision called:
(a) cataract
(b) hypermetropia
(c) myopia
(d) presbyopia
Enumerate the common defects of vision, their causes and the possible methods of correcting them.
Given below is a diagram depicting a defect of the human eye? Study the same and answer the question that follow:
Give two possible reasons for this defect of the eye in human beings.
A person is unable to see objects distinctly placed within 50 cm from his eyes.
(a) Name the defect of vision the person is suffering from and list its two possible causes.
(b) Draw a ray diagram to show the defect in the above case.
(c) Mention the type of lens used by him for the correction of the defect and calculate its power. Assume that the near point for the normal eye is 25 cm.
(d) Draw a labeled diagram for the correction of the defect in the above case.
What type of lens is used to correct Astigmatism?
In Myopia the human eye _______.
Assertion: Myopia is the defect of vision in which a person cannot see distant objects clearly.
Reason: This due to eye-ball being too short.
Observe the figure and answer the following questions:
- Name the defect of vision represented in the above figure.
- State the reasons for this defect.
- How is it corrected?
- Draw the diagram to show the correction of this defect.
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.