Rules for image formation by concave mirror/convex mirror
Rules for image formation by concave mirror/convex mirror :- The image is formed at the point where any two of the following four reflected rays meet or appear to meet/diverge after reflection from the spherical mirror. When the rays actually meet, a real image is formed which is always inverted and if the rays only seem to meet, then a virtual (imaginary) image is formed which is always upright.
(1) Incident ray parallel to principal axis :-
A ray of light which is incident parallel to the principal axis passes through the focus (concave mirror) or appears to pass (convex mirror) after reflection from the mirror.
(2) The ray passing through the focus :-
A ray of light which passes through the focus (concave mirror) or directed towards the focus (convex), becomes parallel to the principal axis after reflection from the mirror.
(3) Ray passing through the center of curvature :-
A ray of light which passes through the center of curvature (concave mirror) or appears to pass (convex mirror), after reflection from the mirror, returns back following the path of incidence.
(4) Ray incident at pole :-
A ray of light which is incident at the pole of the mirror, after reflection from the mirror, returns in the opposite direction at the same angle (with the principal axis).
Next Topics :-
Image Formation By Mirrors