FORMATION OF IMAGES BY SPHERICAL MIRRORS
The best method for formation of images by mirror is through ray tracing. The point at which reflected rays will intersect gives the location of images.
(a) A ray parallel to the axis, after reflection, passes through the focal point of a concave mirror or appears to come from the focal point of a convex mirror.
(b) A ray from (or proceeding towards) the focal point is reflected parallel to the axis.
(c) A ray along the centre of curvature intersects the surface normally and is reflected back along its original path.
(d) A ray incident to the pole is reflected with equal angles with the principal axis.
In any given situation, only two of these rays are sufficient to locate the image.