Question

What is the relation between refractive indices ${\mu }_1,{\mu }_2\text{and}{\mu }_3$ if the behaviour of light rays is as shown in the figure. The refractive index of medium to the left of the lens is ${\mu }_1$ , that of lens is ${\mu }_3$ and that of medium to the right of lens is ${\mu }_2$ .

• A. ${\mu }_3<{\mu }_2,{\mu }_1={\mu }_3$
• B. ${\mu }_2<{\mu }_1,{\mu }_2={\mu }_3$
• C. ${\mu }_3<{\mu }_2<{\mu }_1$
• D. ${\mu }_3>{\mu }_2>{\mu }_1$

Answer 1

The correct option is A

${\mu }_3<{\mu }_2,{\mu }_1={\mu }_3$

The central ray goes undeviated, so, ${\mu }_2={\mu }_1\text{Also},{\mu }_3<{\mu }_2$