The refractive index of the material of a concave lens is $$\mu$$. It is immersed in a medium of refractive index $$\mu_1$$. A parallel beam of light is incident on the lens. The path of the emergent rays when $$\mu_1 > \mu$$ is:

Solution

When the refractive index of the surrounding medium is greater than that of the lens, the nature of the lens reverses. As shown in option (A), the concave lens stops diverging light and instead acts as a converging lens, causing the parallel incident rays to meet at a point.