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Question
Explain two possible reasons of myopia. How can it be corrected? Explain with a suitable diagram.
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Solution
Possible reasons of myopia:-
(i) Ciliary muscles do not relax sufficiently. Therefore, the converging power of the eye lens becomes high.
(ii) The distance between the eye lens and the retina increases (relative to the normal eye) as the eyeball is lengthened (elongated) or the eye lens is curved.
Correcting myopia:-
(i) Myopia is corrected using a suitable concave lens. Light rays are diverged by the concave lens before they strike the eye lens.
(ii) A concave lens of appropriate power is chosen to produce the required divergence. Hence, after the converging action of the eye lens, the image is formed on the retina.
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