That is, r 1 + r 2 > d
Therefore for intersecting circles, sum of the lengths of radii is greater than the
distance between their centers.
Two embossed intersecting circles may be prepared on a sheet of paper and the child
may be facilitated to explore. Once the child conceptualizes the idea of intersecting
circles the distance between their radii may be explained orally. The child can also
measure the radius of each circle separately, add them, and measure the distance
between the centres and realise that r 1 + r 2 > d.
- Non-intersecting circles
Two circles which neither touch nor intersect each other are called non-intersecting
circles.
If r 1 and r 2 denote the radii of the two non-intersecting circles and ādā is the distance
between their centers then, r 1 + r 2 < d. Therefore, for two non-intersecting circles, the
sum of the lengths of their radii is less than the distance between their centers.
Two embossed non-intersecting circles be prepared on a thick sheet of paper and
child be provided with that. On exploration the child will be able to understand that
the sum of their radii is less than the distance between their centers.
- Circles touching externally
Two circles touching each other externally at a single point are said to be circles
touching externally.
O 1 O 2
