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Question
Why is a normal eye not able to see clearly the objects placed closer than 25 cm?
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Solution 1
A normal eye is unable to clearly see objects placed closer than 25 cm because the ciliary muscles of the eyes are unable to contract beyond a certain limit.
Solution 2
A normal eye can see clearly at a distance of no less than 25 cm. So, anything closer than 25 cm will be too close for a normal eye to see clearly.
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