Question

A concave lens _____rays of light whereas convex lens ______ rays of light.
A. Converges, diverges
B. Diverges, diverges
C. Converges, converges
D. Diverges, converges

Answer 1

Hint: To answer this question, we should know the focusing properties of both convex and concave lenses when a beam of light falls on it. These lenses have a property to either converge or diverge a beam of light which falls on it. Concave lens possesses a surface which is curved inside whereas a convex lens possesses a surface which is curved outside. Based on their surfaces, the beam of light either diverges or converges.

Complete step by step answer:
A concave lens is also known as a diverging lens. It is called so because it has a surface which is curved inside and when the parallel beam of light falls on it gets diverged at one point.
A convex lens is also known as a converging lens. It is called so because it has a surface which is curved outside and when the parallel beam of light falls on it gets converged at one point.
Hence, a concave lens diverges rays of light whereas a convex lens converges rays of light.

So, the correct answer is option D i.e. diverges and converges.

Note:
The converging and diverging nature of the lens depends upon the thickness of the lens and also on the refractive index of the lens. Students must understand that the concave lens can be used as a converging lens when the surrounding medium has a refractive index more than that of the material of the lens. A concave lens always forms a virtual image of the object. Whereas the image formed due to a convex lens is always real.