# Curved Mirror

### Curved Mirror

1. A curve is part of a circle. Therefore
1. the centre of the circle will also be the centre of the curve and is called the centre of curvature, and
2. the radius of the circle will be equal to the radius of the curve, called the curvature radius.

#### Important Terms

 Centre of curvature, C The geometric centre of a hollow sphere of which the concave or convex mirror is a part. Pole of mirror, P The centre point on the curved mirror. Principal axis A line which passes through the centre of curvature, C and the pole of a curved mirror, P. Radius of curvature, r Distance between the pole, P and the centre of curvature, C. Principal focus, F A point through which all rays travelling parallel to the principal axis converge to or appear to diverge from after reflection by the mirror. Focal length, f The distance between the principal focus, F and the pole of the curved mirror, P. Aperture of mirror The portion of the surface of the mirror that reflects light. Object distance, u Distance of object from the pole of the mirror, P. Image distance, v Distance of image from the pole of the mirror,