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Cuboid A cuboid has 6 faces, 8 vertices Example: E F
and 12 edges. 6 faces are: ABCD, EFGH, ABEH, H G
CDGF, ADGH, and BCFE
8 vertices are: A, B, C, D, E, F, G, B C
and H A D
12 Edges are: AB, BC, CD, DA, AH, HG, GD, EF, FG,
HE, BE, and CF

Cylinder A cylinder has 3 faces (2 flat and Example:
1 curved face), 2 edges (curved), Edge 1 Face 1
and 0 vertex.
Face 2
Edge 2
Face 3
Cone A cone has 1 vertex, 2 faces (1 Example: Vertex
plane and 1 curved), and 1 edge.
Curved
face

Flat face Curved edge

Sphere A sphere has only 1 face which Curved
is curved. It has no edges and no Example: face
corners.

Prism
A prism is a 3-dimensional solid object which has identical flat faces at both ends. The other
faces are also flat. A prism is named after its base. The faces of the prism are parallelograms or
rectangles and the bases of the prism could be triangle, square, rectangle or any n-sided polygon.
Prism based on the shape of base are

Triangular Prism: A prism with triangular base. It has 5 faces (3 rectangles and 2 triangles), 9
edges and 6 vertices.

Rectangular prism: A prism with rectangular base. It has 6 faces, 12 edges and 8 vertices.
Square Prism: A prism with square base. It has 6 faces (2 squares and 4 rectangles), 12 edges and
8 vertices.

Pentagonal Prism: A prism with pentagonal base. It has 7 faces, 15 edges and 10 vertices.
There are many more prisms other than the above. Some Examples of prism are:

Triangular prism Square prism Rectangular prism Pentagonal prism Hexagonal prism

Maths Talk

If a prism has a triangle as its base, it will have 5 faces: 2 triangular faces and 3 rectangular faces. Now,
if the base is a rectangle, the prism will have 6 faces: 2 rectangular faces and 4 lateral rectangular faces.
What happens if the base has more sides, like a hexagon or heptagon? Can you find a pattern? Can
you generalise the pattern and find the number of faces of a prism if the base is a polygon with n sides?

261 Visualising Solid Shapes