Pentagonal gyrocupolarotunda

Pentagonal gyrocupolarotunda
Type Johnson
J32 - J33 - J34
Faces 3.5 triangles
5 squares
2+5 pentagons
Edges 50
Vertices 25
Vertex configuration 10(32.4.5)
5(3.4.5.4)
2.5(3.5.3.5)
Symmetry group C5v
Dual polyhedron -
Properties convex
Net

In geometry, the pentagonal gyrocupolarotunda is one of the Johnson solids (J33). Like the pentagonal orthocupolarotunda (J32), it can be constructed by joining a pentagonal cupola (J5) and a pentagonal rotunda (J6) along their decagonal bases. The difference is that in this solid, the two halves are rotated 36 degrees with respect to one another.

The 92 Johnson solids were named and described by Norman Johnson in 1966.

Formulae

The following formulae for volume and surface area can be used if all faces are regular, with edge length a:[1]

V=\frac{5}{12}(11%2B5\sqrt{5})a^3\approx9.24181...a^3

A=(5%2B\frac{1}{4}\sqrt{1900%2B490\sqrt{5}%2B210\sqrt{75%2B30\sqrt{5}}})a^2\approx23.5385...a^2

References

  1. ^ Stephen Wolfram, "Pentagonal gyrocupolarotunda" from Wolfram Alpha. Retrieved July 24, 2010.

External links