1. 3D objects
Saturday, 17 November 2018

2. Pyramids
Definition: A pyramid is a solid in which the cross-sectional area reduces to a point.
In other words if the base was a polygon then of each side of the polygon would be a triangular face which all meet at a common vertex.
vertex
face
face

3. 5 8 5 1. square-based pyramid Properties Number of faces =
Number of edges =
Number of vertices =
Has planes of symmetry
Has rotational symmetry from a given axes. 5 8 5

4. Planes of symmetry

5. 4 6 4 2. Tetrahedron Properties Number of faces = Number of edges =
Number of vertices =
Has planes of symmetry
Has rotational symmetry from a given axes. 4 6 4

6. Planes of symmetry

7. 2 3. Cone Properties Number of faces = Has planes of symmetry
Has rotational symmetry from a given axes. 2

8. Planes of symmetry

9. Spheres
Definition: A sphere is not like any prism or pyramid and so is in a category all of its own. A sphere is a perfectly round shape.
Properties
Has an infinite number of planes of symmetry
Has rotational symmetry from a given axes.