CBSE notes-Light

CBSE notes-Light

Principal focus of concave and convex mirror.

:Principal focus of a concave mirror
(i) The principal focus of a concave mirror is a point on its principal axis to which all the light rays, which are parallel and close to the axis, converge after reflection from the concave mirror.

(ii) A concave mirror has real focus.

Principal focus of a convex mirror
(i) The principal focus of a convex mirror is a point on its principal axis from which
a beam of light rays, initially parallel to the axis, appear to diverge after being
reflected from the convex mirror.

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