MCQ
An air bubble in sphere having $4 \mathrm{~cm}$ diameter appears $1 \mathrm{~cm}$ from surface nearest to eye when looked along diameter. If $\mu=1.5$, the distance of bubble from refracting surface is
  • $1.2 \mathrm{~cm}$
  • B
    $3.2 \mathrm{~cm}$
  • C
    $2.8 \mathrm{~cm}$
  • D
    $1.6 \mathrm{~cm}$

Answer

Correct option: A.
$1.2 \mathrm{~cm}$
$v=1\ cm, R=2\ cm$
By using
$u=-\cdot c m$
$\frac{\mu_2}{v}-\frac{\mu_1}{u}=\frac{\mu_2-\mu_1}{R} $
$\frac{1}{-1}-\frac{1.5}{u}=\frac{1-1.5}{-2} $
$\Rightarrow 1.2$

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