Antiprism

bgcolor=#e7dcc3 colspan=2|Pentagonal antiprism
lign=center colspan=2|
Click on picture for large version.
gcolor=#e7dcc3 colspan=2|Heptadecagonal antiprism
lign=center colspan=2|
Click on picture for large version.
gcolor=#e7dcc3|Type Antiprism
gcolor=#e7dcc3|Faces 2 n-gons, 2n triangles
gcolor=#e7dcc3|Edges 4n
gcolor=#e7dcc3|Vertices 2n
gcolor=#e7dcc3|Vertex configuration n,3,3,3
gcolor=#e7dcc3|Symmetry group Dnd
gcolor=#e7dcc3|Dual polyhedron trapezohedron
gcolor=#e7dcc3|Properties convex, semi-regular (vertex-uniform)
An antiprism is a polyhedron composed of two parallel copies of some particular polygon, connected by an alternating band of triangles. Antiprisms are similar to prisms except the bases are twisted relative to each other. Regular right antiprisms form an infinite series of vertex-uniform polyhedra, as do the regular right prisms. The octahedron is a particular type of right triangular antiprism which is also edge- and face-uniform, and so counts among the Platonic solids. The dual polyhedra of the antiprisms are the trapezohedra. Their existence was first discussed and their name was coined by Johannes Kepler. Canonical coordinates for an antiprism with n-gons are (sin(2πk/n), cos(2πk/n), a) with k ranging from 0 to n-1, where
a=\sqrt{\frac{\cos\frac{\pi}{n}-\cos\frac{2\pi}{n}}{2}}.

External links

 

<< PreviousWord BrowserNext >>
aegir
antibiotic
arnold schwarzenegger
actium
amide hydrolysis
amway
adam smith
a plus
antoine lavoisier
alan cox
a roll
adolph wilhelm hermann kolbe
april 18
april 23
amitabh bachchan
allomorph
allophone
affix
allegory
allotropy
agathocles
industry in alberta
augustin louis cauchy
archimedes
alternative medicine
archimedean solid
ecology of africa
geography of africa
approval voting
aromatic compound
arizona state university
april 14
astoria, oregon
alf
alarums and excursions
alfred jarry
amalric
amalric i of jerusalem
amalric ii of jerusalem
anthemius of tralles
absalon
adhemar of le puy
alphonse of toulouse
alphonse i of toulouse