Gyroelongated pentagonal cupolarotunda
{{Short description|47th Johnson solid}}
{{Infobox polyhedron
|image=gyroelongated_pentagonal_cupolarotunda.png
|type=Johnson
{{math|gyroelongated pentagonal bicupola – J{{sub|47}} – gyroelongated pentagonal birotunda}}
|faces=7x5 triangles
5 squares
2+5 pentagons
|edges=80
|vertices=35
|symmetry={{math|C{{sub|5}}}}
|vertex_config={{math|5(3.4.5.4)
2.5(3.5.3.5)
2.5(3{{sup|4}}.4)
2.5(3{{sup|4}}.5)}}
|dual=-
|net=Johnson solid 47 net.png
}}
In geometry, the gyroelongated pentagonal cupolarotunda is one of the Johnson solids ({{math|J{{sub|47}}}}). As the name suggests, it can be constructed by gyroelongating a pentagonal cupolarotunda ({{math|pentagonal orthocupolarotunda}} or {{math|pentagonal gyrocupolarotunda}}) by inserting a decagonal antiprism between its two halves.
{{Johnson solid}}
The gyroelongated pentagonal cupolarotunda is one of five Johnson solids which are chiral, meaning that they have a "left-handed" and a "right-handed" form. In the illustration to the right, each pentagonal face on the bottom half of the figure is connected by a path of two triangular faces to a square face above it and to the left. In the figure of opposite chirality (the mirror image of the illustrated figure), each bottom pentagon would be connected to a square face above it and to the right. The two chiral forms of {{math|J{{sub|47}}}} are not considered different Johnson solids.
Area and Volume
With edge length a, the surface area is
:
and the volume is
:
External links
- {{Mathworld2 | urlname =GyroelongatedPentagonalCupolarotunda | title =Gyroelongated pentagonal cupolarotunda | urlname2 = JohnsonSolid | title2 = Johnson solid }}
{{Johnson solids navigator}}