Q. 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
A) 1.2 $cm$
B) 3.2 $cm$
C) 2.8 $cm$
D) 1.6 $cm$
Explanation
(a) $v = 1\ cm,\ R = 2\ cm$
By using
$\frac{\mu_{2}}{v} - \frac{\mu_{1}}{u} = \frac{\mu_{2} - \mu_{1}}{R}$
$\frac{1}{- 1} - \frac{1.5}{u} = \frac{1 - 1.5}{- 2}$
$\Rightarrow u = - 1.2\ cm$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.