MCQ
A short sighted person can see distinctly only those objects which lie between $10 \mathrm{~cm}$ and $100 \mathrm{~cm}$ from him. The power of the spectacle lens required to see a distant object is
  • A
    $+0.5 D$
  • $-1.0 \mathrm{D}$
  • C
    $-10 \mathrm{D}$
  • D
    $+4.0 \mathrm{D}$

Answer

Correct option: B.
$-1.0 \mathrm{D}$
$f=-d=-100 \mathrm{~cm}=-1 \mathrm{~m}$
$\therefore P=\frac{1}{f}=\frac{1}{-1}=-1 D$

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