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प्रश्न
A student is unable to see clearly the words written on the black board placed at a distance of approximately 3 m from him. Name the defect of vision the boy is suffering from. State the possible causes of this defect and explain the method of correcting it.
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उत्तर
The boy is suffering from nearsightedness i.e. Myopia. The possible causes for this defect are Elongation of the eyeball.
Excessive curvature of the eye lens
This defect can be corrected by placing a concave lens in front of the eye.

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संबंधित प्रश्न
Which defect of vision can be rectified:
by using a concave lens?
A man can read the number of a distant but clearly but he finds difficulty in reading a book.
From which defect of the eye is he suffering?
Write whether the following is true or false:
A convex lens is used for correcting myopia.
Explain the Term: Cataract
Give Technical Term:
The type of lens used to correct myopia is
Mention, if the following statement is True or False
Hypermetropia is a defect of the eye caused due to the eyeball elongation
Observe the given below the figure, correct it and explain and write about the concept depicted in this figure.

Myopia may arise due to ____________.
When do we consider a person to be myopic or hypermetropic? Explain using diagrams how the defects associated with myopic and hypermetropic eye can be corrected?
A person is unable to see clearly a poster fixed on a distant wall. He however sees it clearly when standing at a distance of about 2 m from the wall.
- Draw ray diagram to show the formation of image by his eye lens when he is far away from the wall.
- List two possible reasons of this defect of vision.
- Draw ray diagram to show the correction of this defect using appropriate lens.
