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Question
Given below is a diagram showing a defect of vision. Name the defect of vision and draw an accurately labelled diagram to correct this defect.
Solution
Name of defect: Farsightedness or hypermetropia
Correction of Farsightedness:
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if the person is an old man
A person can read a book clearly only if he holds it at an arm's length from him. Name the defect of vision:
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What is meant by optical illusion? Give one example.
You do not enjoy watching a movie from a very short distance from the screen in a cinema hall. Why?
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Name the defect shown in the diagram.
Have a look at the posture of this girl who is reading a book and answer the questions which follow:
Name the problem she is facing.
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Given alongside is a diagram depicting a defect of the human eye. Study the same and then answer the questions that follow:
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Given below is a diagram depicting a defect of the human eye? Study the same and answer the question that follow:
Draw a labeled diagram to show how the above mentioned defect is rectified using the lens named above.
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
|
Nearsightedness
|
Concave lens.
|
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Give Reason:
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An inability to focus on nearby objects due to loss of elasticity of the lens with age is called Iris.
Nearsightedness: elongated eyeball : : farsightedness: _______
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Name the following:
Two kinds of accomodations.
