(a) A person cannot see nearby objects, then write name of eye defect. Write name of lens used to correct this eye defect.
(b) In brief define 'Tyndall effect'.

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Solution

A. Hypermetropia is the defect of vision in which a person can see distant objects clearly and distinctively, but is not able to see nearby objects comfortably and clearly. In this defect, the rays coming from object converge at point behind the retina. Since a convex lens has the ability to converge incoming rays, it can be used to correct this defect of vision
B. The Tyndall effect, also known as Willis–Tyndall scattering, is light scattering by particles in a colloid or in a very fine suspension.

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(a) A person cannot see nearby objects, then write name of eye defect. Write name of lens used to correct this eye defect.(b) In brief define 'Tyndall effect'.

(a) A person cannot see nearby objects, then write name of eye defect. Write name of lens used to correct this eye defect.
(b) In brief define 'Tyndall effect'.