The far point of a myopic person is 80 cm in front of the eye. What is the nature and power of the lens required to correct the problem?
Focal length of the myopic person is given, 80 cm. The focal length should be in meters and the person has the eye defect of myopia so the focal length would be in minus (-).
So, Focal length (f) = 80 cm. = -0.8 m.
Formula used, Power of the lens (P) = 1/ f
P = 1/ -0.8
P = - 1.25 D , where D is the dioptre
The image will not formed on retina in this defect it will form in the front of retina. And, this defect can be corrected by the concave lens of the suitable power.
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