A light source is kept in air $(n \approx 1)$ at a distance of 200 cm from a convex spherical glass surface $\left(n=\frac{3}{2}\right)$ such that light falls on it. If the radius of curvature of the surface is 40 cm, the position of the image is at
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → +200 cm
$\mu_2=\frac{3}{2}, \mu=1$
R = 40 cm
u = -200 cm
$\frac{\mu_2}{v}-\frac{\mu_1}{u}=\frac{\mu_2-\mu_1}{R}$
$\frac{1.5}{v}+\frac{1}{200}=\frac{1.5-1}{40}$
$\frac{1.5}{v}=\frac{5}{400}-\frac{1}{200}$
v = 200 cm