Question

A concave lens made of material of refractive index of n1 is kept in medium of refractive index n2. A parallel beam of light is incident on the lens. Complete the path of rays of light emerging from the concave lens if,

• A. n1 > n2
• B. n1 = n2
• C. n1 < n2
• D. none of these

Answer 1

The correct option is A n1 > n2

In this case, $n_1>n_2$, i.e, medium of concave lens is denser than the medium from where light ray is incident on it.

Therefore , at entering surface, the light ray bends towards the normal $n_1$, while leaving the lens, the ray again goes under refraction at leaving surface and in this situation it bends away from the normal $n_2$.

$\therefore$ Option $A$ is correct.