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Question
Given alongside is a diagram depicting a defect of the human eye. Study the same and answer the questions that follow:
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- Name the defect shown in the diagram.
- Give two possible reasons for this defect.
- Name the parts labelled 1 to 4.
- Name the type of lens used to correct this eye defect.
- Draw a labelled diagram to show how the above mentioned defect is rectified using the lens named above.
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Solution
- Shortsighted, or myopia.
- The eyeball becomes long from front to back. The lens becomes too curved/convex.
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- Vitreous humour
- Blind spot
- Lens
- Pupil
- Concave lens
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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:
Give two possible reasons for this defect of the eye in human beings.
Solve the following question:
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A person cannot see distinctly objects kept beyond 2 m. This defect can be corrected by using a lens of power:
