MCQ
An air bubble in sphere having $4 \,cm$ diameter appears $1 \,cm$ from surface nearest to eye when looked along diameter. If $_a\mu_g = 1.5$, the distance of bubble from refracting surface is.....$cm$
- ✓$1.2$
- B$3.2$
- C$2.8 $
- D$1.6$
✓
Answer
Correct option: A.
$1.2$
a
(a) $v = 1 \,cm, R = 2 \,cm$
By using
$\frac{{{\mu _2}}}{v} - \frac{{{\mu _1}}}{u} = \frac{{{\mu _2} - {\mu _1}}}{R}$
$\frac{1}{{ - 1}} - \frac{{1.5}}{u} = \frac{{1 - 1.5}}{{ - 2}}$
$ \Rightarrow u = - 1.2\,cm$
(a) $v = 1 \,cm, R = 2 \,cm$
By using
$\frac{{{\mu _2}}}{v} - \frac{{{\mu _1}}}{u} = \frac{{{\mu _2} - {\mu _1}}}{R}$
$\frac{1}{{ - 1}} - \frac{{1.5}}{u} = \frac{{1 - 1.5}}{{ - 2}}$
$ \Rightarrow u = - 1.2\,cm$
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