What is the minimum number of rays required for locating the image formed by a concave mirror for an object ? Draw a ray diagram to show the formation of a virtual image by a concave mirror.

Explanation

A minimum of two rays are required for locating the image formed by a concave mirror for an object. When the object AB is held between pole P and principal focus F of the concave mirror, the image formed, A'B' is virtual, erect and magnified as