Question

A rectangular acrylic plane mirror bent in such way that it acts as a concave mirror with out changing its length and breadth can we change its focal length guess and write

Answer 1

Answer:

This is not a biology question

This is a physics one

Answer 2

The focal length can be changed by-

Focal length - the distance between the centre of mirror(pole) and the point where the reflected rays converge.

The focal length of a plane mirror is infinity because there's no focal point for the rays to converge.

As soon as it is bent to a concave mirror, the reflected rays meet at the focal point away from the pole and the focal length becomes definite.

Hence, length or breadth of the mirror is not changed but still the focal length changes.