CBSE 2025 · Region 6 · Set 1 · Q32 · 3 marks
A person uses lenses of +$\displaystyle 2.0$ D power in his spectacles for the correction of his vision.(a)Name the defect of vision the person is suffering from.(b)List two causes of this defect.(c)Determine the focal length of the lenses used in the spectacles.
A person uses lenses of +$\displaystyle 2.0$ D power in his spectacles for the correction of his vision.
(a)
Name the defect of vision the person is suffering from.
(b)
List two causes of this defect.
(c)
Determine the focal length of the lenses used in the spectacles.
Marking-scheme solution
(a) Hypermetropia
(b) Two causes:
Eye ball has become too small /Eye ball is shortened
The focal length of the eye Lens is long / eye lens becomes
less convergent(c) \[\begin{aligned}
\text { Focal length } & =\frac{1}{P} \\
& =\frac{1}{2}=+0.5 \mathrm{~m}
\end{aligned}
\]
The Human Eye and the Colourful WorldDefects of Vision and their CorrectionApplyshort_answereasy
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CBSE Class 10 Science past-paper question from the 2025board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.