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Why does a hypermetropic eye have its near point farther than 25 cm?
AThe retina is too thick
BThe eyeball is too long
CThe eyeball is too short or the lens is too flat
DThe pupil is too small in general usage
Answer & Solution
Correct answer: C. The eyeball is too short or the lens is too flat
1. In hypermetropia the eye's converging power is too weak.
2. This happens when the eyeball is too short relative to the lens.
3. Alternatively the lens may be too flat (low curvature).
4. Near rays converge behind the retina, giving a blurred image.
5. So the near point shifts farther than 25 cm.
6. A convex lens compensates by adding converging power.
_Source: NCERT Class 10 Science Ch 11 'Human Eye and the Colourful World'_
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