Question

a person need a lens of power -4.5 D for the . 1) what kind of defect in vesion is see sufring from . 2) what is the focal length of the caractive lens . 3) what is the nature of carative lens.

Answer 1

P = 1 /f

-4.5 = 1 /f

f = -1 /4.5

f = -0.22 m

He is suffering from Myopia.

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