Question

State whether true or false:
A concave lens, if kept at a proper distance from an object, can form its real image.
(A) True
(B) False

Answer 1

Hint:A concave lens is a lens which has both of the side curved inwards (like front face of the spoon). It is also called diverging lens, because when refracted they get diverged outwards.A concave lens always forms a virtual, erect and diminished image whatever may be the position of the object.

Complete step by step answer:
There are two case of image formation for concave lens:
Case 1. When Object is at infinity:

When an object is kept at infinity, the image is formed at the focus and virtual. The size of the image is much smaller than that of the object (highly diminished).
Case 2. When object is placed at any finite distance between pole and infinity:

The image is formed between the pole and optical center, and it is very small.
So, we can observe that a concave lens always forms a virtual, erect and diminished image whatever may be the position of the object.Because the image is actually formed by the intersection of virtually extended refracted rays. So, we can infer that the concave lens can never form a real image.
Therefore, answer is false.

Note:Sometimes students get confused in between concave and convex lens so remember that convex lens is thicker at center and thin at the edges we can feel this by touching.Concave lens is thinner at the center while thick at the edges so whenever you have been given an unknown lens then you can identify it with the help of this information.