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

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

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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