Page 4 - Lesson note reflection through spherical mirror

From the figure given above it can be clearly seen that the light rays passes through
principle focus in case of concave mirrors and appears to diverge from principle
focus in case of concave mirror.

(2) Rule 2

A ray of light passing through the center of curvature of the curvature of the concave
mirror or directed in the direction of the center of curvature of a convex mirror, is
reflected back along the same path as shown below in the figure

This happens because the incident rays fall on the mirror along the normal to the
reflecting surface.

(3) Rule 3

A ray passing through principle focus of a concave mirror or a ray which is directed
towards the principal focus of a convex mirror, becomes parallel to the principle axis
after reflection and is shown below in the figure

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