Question

Observe the given figure carefully. The given figures show the path of light through lenses of two different types, represented by rectangular boxes A and B. What is the nature of lenses A and B?

Fig \( 15.1 \)

Answer 1

Converging or convex lens

1. A converging lens is a lens that converges parallel light rays coming towards them.
2. It forms the real image
3. Convex lens is another name for a converging lens.

Diverging lens or concave lens

1. A diverging lens is a lens that diverges parallel light rays coming toward them
2. It forms the virtual image.
3. Concave lens is another name for a diverging lens.

Diagrams of a convex and concave lens

Diagram of a converging lens Diagram of a diverging lens

Identification of lenses A and B

1. In figure A, the lens is converging the parallel light rays in the point of direction, so the given lens is a converging lens or convex lens.
2. In figure B, the lens is diverging the parallel light rays from the point of direction, so the given lens is a diverging lens or concave lens.

Therefore, lens A is a convex lens and lens B is a diverging lens.