Triangular prism
From Freepedia
| Triangular prism | |
|---|---|
| Image:Triangular prism.png | |
| Type | Semiregular polyhedra |
| Faces | 2 triangles 3 square |
| Edges | 9 |
| Vertices | 6 |
| Vertex configuration | 3.4.4 |
| Wythoff symbol [1] | 2 3 | 2 |
| Symmetry group | D3h |
| Dual polyhedron | Triangular_dipyramid |
| Properties | convex |
| Image:Triangular prism vertfig.png Vertex Figure | |
In geometry, a triangular prism or three-sided prism is a polyhedron made of a triangular base, a translated copy, and 3 faces joining corresponding sides. Equivalently, it is a pentahedron of which two faces are parallel, while the surface normals of the other three are in the same plane (which is not necessarily parallel to the base planes). These three faces are parallelograms. All cross-sections parallel to the base faces are the same triangle.
For a right triangular prism the plane of the surface normals of the three planes the three planes is parallel to the base planes. In this case the parallelograms are rectangles.
A right triangular prism is semiregular if the base faces are equilateral triangles, and the other three faces are squares.
The dual of a triangular prism is a 3-sided bipyramid.
The symmetry group of a right 3-sided prism with regular base is D3h of order 12. The rotation group is D3 of order 6.
The symmetry group does not contain inversion.
See also
- Set of prisms
- Cube Square-capped prism
- Pentagonal prism
- Hexagonal prism
