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Question
Give scientific reason:
We cannot clearly see an object kept at a distance less than 25 cm from the eye.
Solution
- The muscles attached to the eye lens (ciliary muscles) help in fine adjustments of the focal length of the lens.
- The capacity of these muscles to contract or relax to adjust the focal length (i.e., power of accommodation) has a limit.
- The minimum distance of an object from a normal eye for which the eye lens can decrease its focal length to the least possible value, is 25 cm.
Hence, we cannot clearly see an object kept at a distance less than 25 cm from the eye.
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