Question

An air bubble is present in a glass $(\mu$ = 1.5) at a distance of $3\text{cm}$ from the curved convex surface of radius $5\text{cm}$. Position of the image of bubble is
($\mu$ is refraction index)

• A. $1.67\text{cm}$
• B. $2.5\text{cm}$
• C. $3.8\text{cm}$
• D. $6\text{cm}$

Answer 1

The correct option is B $2.5\text{cm}$

As we know that the refraction through curved surface is given by,
$\frac{{\mu }_2}{v}-\frac{{\mu }_1}{u}=\frac{{\mu }_2-{\mu }_1}{R}$

$\frac{1}{v}-\frac{1.5}{-3}=\frac{1-1.5}{-5}$

$\frac{1}{v}+0.5=0.1$

$\frac{1}{v}=-0.4$

$v=\frac{-1}{0.4}\text{cm}=-2.5\text{cm}$