My grandfather uses a bifocal lens in his spectacles. Explain why… - Vidyadip

Question

My grandfather uses a bifocal lens in his spectacles. Explain why.

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Answer

In old age, people usually suffer from both myopia and hypermetropia. Therefore, they need spectacles having bifocal lenses.

The upper part of a bifocal lens is a concave lens to correct myopia. The lower part of a bifocal lens is a convex lens to correct hypermetropia.

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