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Let's catch up with the 3D crew to learn about the properties of 3D shapes!

3D shapes have three dimensions - length, width and depth. 3D shapes have different properties:

Faces - A face is a flat surface on a 3D shape. For example a cube has 6 faces.

Edges - An edge is where two faces meet. For example a cube has 12 edges.

Vertices - A vertex is a corner where edges meet (the plural is vertices). For example a cube has 8 vertices.

Take a look at these common 3D shapes and their properties:

Sphere

Balls are shaped like a sphere.

Properties:

• 1 curved face
• No vertices
• No edges

Cube

Dice and sugar cubes are shaped like cubes.

Properties:

• 6 faces (all shaped like squares)
• 12 edges
• 8 vertices

Cuboid

Fridges and wardrobes are usually shaped like cuboids.

Properties:

• 6 faces (all rectangular, or a mixture of rectangles and squares)
• 12 edges
• 8 vertices

Square-based pyramid

The pyramids in Egypt look like square-based pyramids. They are called square-based pyramids because the face on the bottom is a square.

Properties:

• 5 faces (1 square and 4 triangular)
• 8 edges
• 5 vertices

Cone

Ice cream cones, traffic cones and birthday hats are shaped like cones.

Properties:

• 2 faces (1 circular at the base and 1 curved)
• 1 edge around the base
• 1 vertex

Cylinder

These look like tubes and toilet rolls.

Properties:

• 3 faces (2 circular and 1 curved)
• 2 edges
• 0 vertices

Tetrahedron

A tetrahedron can also be called a triangular-based pyramid.

Properties:

• 4 faces (all triangular)
• 6 edges
• 4 vertices

Triangular prism

Door stops and tents are examples of triangular prisms.

Properties:

• 5 faces (2 triangular and 3 rectangular)
• 9 edges
• 6 vertices

Prisms have two ends that are the same shape and size.

They have the same cross-section all along the shape. If you cut through them at any point you would see the same 2D shape as at either end.

There are other examples of prisms, including hexagonal prisms, like the one below.

Fill in the gaps to identify the different 3D shapes.

Match the shapes with their 3D properties.