Tue March 01, 2011 By: Ansh Arvind

Can we say that the focal length of the human eye is 25cm?

Expert Reply
Tue March 01, 2011
Dear student,
the near point of a normal human eye is 25cm,so our eyes cannot focus clearly on the objects near than 25cm. When the ciliary muscles are relaxed, the eye lens becomes thin, the focal length increases, and the distant objects are clearly visible to the eyes. To see the nearby objects clearly the ciliary muscles contract making the eye lens thicker.Hence, by observations, it s found that the near point of our human eye is 25cm.
Hope this helps.
Thanking you
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