Polyhedron of Soccer Balls Used by UEFA for European Soccer Competitions.

A polyhedron above was used to make a soccer ball. It consists of 92 faces – 12 regular pentagons, 20 hexagons and 60 triangles. For each regular pentagon there are corresponding 5 neighboring triangles. These 6 faces are made with only one piece of material. They are colored with one color. That is why this polyhedron looks like:

With a little difference: instead of blue color there is a black color, instead of yellow color there is a white color.

Let us mention here that not so long time ago a different type of polyhedrons was used for soccer balls production. This was a semi-regular polyhedron built of regular hexagons and regular pentagons:

This polyhedron is also presented on the page of ‘Literka’ example of a semi-regular polyhedron.

This design was used for FIFA international competitions (it was colored with one color – white).

Let us consider why these designs were changed. Of course a soccer ball must remind a ball in an ordinary geometrical sense. A high pressure inside ball causes that the surface reminds more a sphere rather than a polyhedron. But still a good soccer ball must be round even without this pressure.

‘Literka’ was considering what determines a value of design of a soccer ball. Let us consider a ratio of the radius of inscribed sphere of a polyhedron to the radius of the circumscribed sphere. This ratio must be as much close to 1 as possible. Of course this ratio is the best for a new design.

On the other hand, a ball cannot have too many joints. This limits the number of faces of a design polyhedron.

Return to the main geometrical page of 'Literka'.

Return to the main page of ‘Literka’.