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Question
Given below is a diagram depicting a defect of the human eye. Answer the questions that follow:
- Give the scientific term for the defect.
- Mention one possible reason for the defect.
- What type of lens can be used to correct the defect?
Solution
- Myopia (short-sightedness)
- There are two possible reasons for myopia one is the eyeball is lengthened from front to back and the other is the lens is too curved. Both these reasons might as well occur together.
- Myopia can be corrected by using a suitable concave (diverging) lens which causes the light rays to diverge before they strike the lens of the eye.
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| Column - I | Column - II | ||
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