Curved Spherical Mirrors Images in Curved Mirrors n

Curved / Spherical Mirrors

Images in Curved Mirrors n Concave mirrors are shaped like part of the inside of a sphere, with the centre further from the object than the edges. n Convex mirrors are shaped like part of the outside of a sphere, with the centre closer to the object than the edges.

Convex

n Concave

n n The Centre of Curvature ‘C’ is the centre of the sphere of which the curved mirror forms a part. The Pole ‘P’ is the midpoint of the mirror. The Principal Axis is the straight line passing through the pole and the centre of curvature of a spherical mirror. The Normal at any point of a curved mirror is the straight line joining that point with the centre of curvature C of the mirror.

n A tangent is a line that touches a curve at exactly one point without going through it. Tangent Normal Centre of Circle

Focus on the Concave Mirror n n Rays of light parallel to the principal axis of a mirror, reflect through a point (in case of a concave mirror) on the principal axis. This point is the focus or focal point ‘f’ of the mirror. A concave mirror is also known as a converging mirror The focus is in front of the mirror. The focus is real as the rays of light after reflection converge at the focus.

Focus on the Convex Mirror n n In a convex mirror, rays of light (parallel to the principal axis of a mirror), appear to diverge from a point on the principal axis. This point is the focus or focal point ‘f’ of the mirror. A convex mirror is also known as a diverging mirror The focus is behind the mirror The focus is virtual as the rays of light after reflection appear to come from the focus behind the mirror