MCQ
For the myopic eye, the defect is cured by
  • A
    Convex lens
  • Concave lens
  • C
    Cylindrical lens
  • D
    Toric lens

Answer

Correct option: B.
Concave lens
b
(b) In myopia, $u = \infty ,$ $v = d = $ distance of far point

By $ = \frac{{1}}{{f}} =  \frac{{1}}{{v}} -  \frac{{1}}{{u}},$ we get $f = - \;d$

Since $f$ is negative, hence the lens used is concave.

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