Physics - Geometrical Optics Question with Solution | TestHub

We know that;

$\frac{{\text{μ}}_2}{\text{v}}-\frac{{\text{μ}}_1}{\text{u}}=\frac{{\text{μ}}_2-{\text{μ}}_1}{\text{R}}$

$\frac{1}{\text{v}}-\frac{3}{2\times 30}=\frac{1-\frac{3}{2}}{+20}$

$\frac{1}{\text{v}}=-\frac{1}{40}+\frac{1}{20}=+\frac{1}{40}$

$\mathrm{v}=40 \mathrm{cm}$.