Question

Draw suitable rays by which we can guess the position of image formed by a concave mirror?

Answer 1

We choose the following rays emanating from the object in order to decide the position of the object. We keep the object on the principal axis in an erect position.

1. Ray from top of the object B towards the mirror, paraxially. reflects thru Focus.
2. Ray from top of the object B  towards the pole of the mirror.
3. Ray from top of the object B through center C of mirror, retraces its path after reflection.
4. Ray from the bottom of the object A, along the principal axis.

See diagram

Answer 2

Answer:

The following rays are used to guess the position of the image formed by a concave mirror. i) A ray parallel to the principal axis passing through principal focus (F) after reflection from a concave mirror. ii) A ray passing through 'F' becomes parallel to principal axis after reflection from a concave mirror.