Question
How are we able to see nearby and also the distant objects clearly?
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Answer
Human eyes have power of accommodation. When we have to see distant objects, the eye muscles relax and lens becomes thin. Due to this, the focal length of the lens increases and the eye is able to see distant objects. When we have to see nearby objects, the eye muscles contract and lens becomes thick. Due to this, the focal length of the lens decreases and the eye is able to see nearby objects.
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