• A curved mirror can be formed

from part of a sphere.

• There are two general types of curved mirrors.– A concave mirror causes light rays that are

parallel to the principal axis to converge, ormeet, at one point (the focus).

– A convex mirror causes parallel light rays to diverge, or spread apart.

11.9PROPERTIES OF CURVED MIRRORS

concave

(converging)mirror

principal axis

converge

focus

centre of curvature

vertex

convex (diverging)

mirror

diverge

principal axis

centre ofcurvature

vertex

• There are four imaging rules that you can use to locate the image of an object

in a converging mirror.

11.9HOW TO LOCATE THE IMAGE IN ACONVERGING (CONCAVE) MIRROR

A light ray through the centre of curvature is reflected back onto itself.

A light ray parallel to the principal axis is reflected through the focus. This is how the focus is defined.

A ray through F will reflect parallel to the principal axis.

A ray aimed at the vertex will follow the law of reflection.

• Images in converging mirrors can be described using the same characteristics

as with plane mirrors: size, attitude, location, and type.

• The image characteristics change, depending on where the object is located

relative to the mirror.

11.9IMAGE CHARACTERISTICS INCONVERGING MIRRORS

• There are three imaging rules that you can use to locate the image of an object

in a diverging mirror.

11.9HOW TO LOCATE THE IMAGE INA DIVERGING (CONVEX) MIRROR

• Images in diverging mirrors can be described using the same characteristics as

with converging mirrors: size, attitude, location, and type.

• The image characteristics are always the same, no matter where the object is

located relative to the mirror.

• The image is smaller, upright, behind the mirror, and virtual.

11.9IMAGE CHARACTERISTICS INDIVERGING MIRRORS

• We use curved mirrors in many ways.

11.9APPLICATIONS OF CURVED MIRRORS

Type of Mirror Where Mirror is Used Where Object is Located

converging mirror parabolic solar collector, parabolic solar cookercar headlightflashlightsearchlightreflecting telescoperadio telescopesatellite dish

beyond F

shaving mirrormakeup mirror

between F and mirror

diverging mirror security mirrorside-view mirror on a vehicle

any location