Elongated pentagonal gyrocupolarotunda explained

Type:Johnson
Faces:3x5 triangles
3x5 squares
2+5 pentagons
Edges:70
Vertices:35
Dual:-
Properties:convex
Net:Johnson solid 41 net.png

In geometry, the elongated pentagonal gyrocupolarotunda is one of the Johnson solids . As the name suggests, it can be constructed by elongating a pentagonal gyrocupolarotunda by inserting a decagonal prism between its halves. Rotating either the pentagonal cupola or the pentagonal rotunda through 36 degrees before inserting the prism yields an elongated pentagonal orthocupolarotunda .

Formulae

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

V=5
12

\left(11+5\sqrt{5}+6\sqrt{5+2\sqrt{5}}\right)a3 ≈ 16.936...a3

A=1
4

\left(60+\sqrt{10\left(190+49\sqrt{5}+21\sqrt{75+30\sqrt{5}}\right)}\right)a2 ≈ 33.5385...a2

Notes and References

  1. [Stephen Wolfram]