Square pyramid
Appearance
Square pyramid | |
---|---|
Type | Johnson J92 - J1 - J2 |
Faces | 4 triangles 1 square |
Edges | 8 |
Vertices | 5 |
Vertex configuration | 4 of 32.4 1 of 34 |
Symmetry group | C4v |
Dual polyhedron | self |
Properties | convex |
In geometry, the square pyramid, a pyramid with a square base and equilateral sides, is one of the Johnson solids (J1).
The 92 Johnson solids were named and described by Norman Johnson in 1966.
It is worth noting that the Johnson solid "square pyramid" is specifically the one square pyramid whose triangular sides are all equilateral triangles. Other square pyramids, such as the Great Pyramid of Giza, are not similar to the Johnson solid; the pyramid at Giza, for example, has isosceles sides of base 756 feet and slant height 719 feet. (That pyramid has the interesting property that the area of each triangular face is equal to the square of its height.)
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