Q14 of 56 Page 1

(a) What is meant by the power of accommodation of an eye?

(b) A person with a myopia eye cannot see objects beyond 1.2 m directly. What should be the type of the corrective lens used? What would be its power?

(a) Power of the accommodation of an eye is defined as the ability of an eye to change its focal length so as to focus the distant objects as well as nearby objects on the retina.

(b) Myopia eye


Image distance, v= 1.2 m


In cm , v = -120 cm


V = 1.2 m =-120


Object distance for a myopic eye, u = (infinity)


Applying the lens formula






F = -120 cm =-1.2 m


Since focal length is negative, so lens is concave lens.


Power is defined by the relation


P = 1/ f


P =


P =-0.83 D


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