Question

A converging beam from water to air is shown in figure. Beam after deviating due to refraction will converge at what distance from surface of water? (refractive index of water is $\frac{4}{3}$)

• A. 18 cm
• B. 32 cm
• C. $\infty$
• D. 16 cm

Answer 1

The correct option is A 18 cm

$\frac{n_r}{v}=\frac{n_i}{u}$
$\frac{1}{v}=\frac{4/3}{24}$
$\frac{1}{v}=\frac{4}{3\times 24}=\frac{1}{18}$
$v$ = 18 cm