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Question
What eye defect is hypermetropia? Describe with a ray diagram how this defect of vision can be corrected by using an appropriate lens.
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Solution
Hypermetropia is a defect of vision in which a person cannot see nearby objects clearly, but has no problems in seeing distant objects. Corrected vision for a hypermetropic eye by using a convex lens:
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RELATED QUESTIONS
What is the other name for
hypermetropia
Though a woman can see the distant object clearly, she cannot see the nearby objects clearly. She is suffering from the defect of vision called:
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Rods and cones (sensitivity).
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(a) Name the defect of vision the person is suffering from and list its two possible causes.
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(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.
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Short-sightedness and Long-sightedness.
Study the following diagram carefully and then answer the questions that follow. The diagram is depicting a defect of the human eye :
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(ii) Give two possible reasons for the above defect.
Nearsightedness : concave lens : : farsightedness : _______
Observe the figure and answer the following questions:
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- State the reasons for this defect.
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- Draw the diagram to show the correction of this defect.
