An old man cannot see objects closer than 1 m from the eye clearly. Name the defect of vision he is suffering from. How can it be corrected? Draw ray diagram for the (i) defect of vision and also (ii) for its correction.

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Solution

The man is suffering from hypermetropia, or farsightedness. He cannot see nearby objects clearly because the eyelens does not have enough converging power to converge the light from nearby objects on the retina. Hence an external converging lens is used to focus on the nearby objects.

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