The eyes of a person are focused (i) on a nearby object, and (ii) on a distant object, turn by turn. In which case :
(a) the focal length of eye-lens will be the maximum ?
(b) the converging power of eye-lens will be the maximum ?

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Solution

When the eye focuses on a near object, the ciliary muscle contracts. As a result, both lens surfaces become more curved and thicker(more convex)

When the eye focuses on a distant object, the ciliary muscles will relax which causes the lens to be flatten and thinner(less convex)

(a)When the eyes is focused on a distant object
(a)When the eyes is focused on a nearby object

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The eyes of a person are focused (i) on a nearby object, and (ii) on a distant object, turn by turn. In which case : (a) the focal length of eye-lens will be the maximum ? (b) the converging power of eye-lens will be the maximum ?

The eyes of a person are focused (i) on a nearby object, and (ii) on a distant object, turn by turn. In which case :
(a) the focal length of eye-lens will be the maximum ?
(b) the converging power of eye-lens will be the maximum ?