Question

why is a concave lens called diverging lens

Answer 1

The concave lens is also known as diverging lens because it diverges the light rays passing towards it like the image.

Answer 2

Answer:

Because it diverges all rays of light parallel to the principal axis such that they appear to meet at the principal focus.

Explanation:

A concave lens is thinner at its center than at its edges.

It is also known as a diverging lens because it always diverges all rays parallel to the principal axis such that they appear to meet at the principal focus.

In the attached figure, point A is the Principal Focus of the concave lens.