Short Overview of Polyhedra Systems: Static and Dynamic

5 Platonic "Solids" And Friends

NAME VERTICES EDGES FACES

TETRA. BASED
VOLUME EQU.
F=Edge Freq.


SHELL GROWTH
2×N×F2 + 2
F=Edge Freq.
EULER'S EQUATION
V + F = E + 2
V=Num. Vertices
F=Num. Faces   
E=Num. Edges   
V×360° - ∑Surf.A. = 720°
Tetrahedron 1 F3 2×(1)× F2 + 2 V = 4
F = 4
E = 6
4 + 4 = 6 + 2
4×360° - 4×3×60°
1440° - 720° = 720°
Octahedron 4 F3 2×(2)× F2 + 2 V = 6
F = 8
E = 12
6 + 8 = 12 + 2
6×360° - 8×3×60°
2160° - 1440° = 720°
Hexahedron
(Cube)
3 F3 2×(3)× F2 + 2 V = 8
F = 6
E = 12
8 + 6 = 12 + 2
8×360° - 6×4×90°
2880° - 2160° = 720°
Rhombic
Dodecahedron
6 F3 2×(6)× F2 + 2 V = 14
F = 12
E = 24
14 + 12 = 24 + 2
5040° - 4320° = 720°
Icosahedron ≈18.51...F3 2×(5)× F2 + 2 V = 12
F = 20
E = 30
12 + 20 = 30 + 2
12×360° - 20×3×60°
4320° - 3600° = 720°
Dodecahedron ≈ 65.02...F3   V = 20
F = 12
E = 30
20 + 12 = 30 + 2
20×360° - 12×5×108°
7200° - 6480° = 720°
Rhombic
Triacontahedron
≈104.46...F3   V = 32
F = 30
E = 60
32 + 30 = 60 + 2
11520° - 10800° = 720°

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Copyright September, 2007 by Robert W. Gray