11.9 Blog: Images in Curved Mirrors

The Terminology of Concave Mirrors
A concave mirror, which is also known as a converging mirror is a mirror that is shaped like the mirror is curving outwards. A convex mirror, which is also known as a diverging mirror is a mirror shaped like the mirror is curving inwards. The centre of curvature of a mirror is when the spheres surface is used to make the mirror. The principal axis of the mirror is a line which goes through the centre of curvature and the centre of the mirror.The vertex is where the principal axis meets the mirror.

principal axis

How to Locate an Image in a Concave Mirror

To find out what the image of an object that is in front of a concave mirror, you will have to draw two or more incident rays beginning at the top of an object. The rays might form an image and reflect off the mirror.

1. To determine the focus a light ray parallel to the principal axis is reflected through the focus.
2. When a light ray goes through the centre of curvature (C) it's then reflected back onto itself.
3. When a light ray goes through F it will reflect parallel to the principal axis..
4. When a light ray is directed at the vertex it will follow the law of reflection. The surface of the mirror is vertical to the principal axis so the angle of incidence will be measured easily.

How to Locate an Image in a Convex Mirror

To find out 

1. When a light ray is parallel to the principal axis it is reflected as if it went through the focus.
2. When a ray is directed toward the centre of curvature it is reflected back to itself.
3. When a ray is directed toward the focus it is reflected to the principal axis.

examples of concave mirrors: a car headlight, a searchlight and a flashlight.
examples of convex mirrors: security mirrors,

Link on how to locate the image in a convex mirror
http://www.physicsclassroom.com/class/refln/u13l4b.cfm


Link on how to locate the image in a concave mirror
http://www.physicsclassroom.com/class/refln/u13l3d.cfm




By: M.B.