Concentric circles

Concentric circles are a set of two or more circles in the same plane that share a common center but have different radii. The distance between the circles at any point is equal to the difference of their radii.

Important properties

• Concentric circles never intersect.

• The region between two concentric circles forms an annulus (a ring-shaped area).

• All radii drawn from the common center to any of the circles are collinear.

• Any line passing through the common center is an axis of symmetry for all the concentric circles.