Class 7 Maths Visualising Solid Shapes | Faces, Edges and Vertices |

__Faces, Edges and Vertices__

Let us consider a cube.

Each side of the cube is a flat surface called a flat face or simply a face.

When two faces meet at a line segment then it is called an edge.

Three edges meet at a point called a vertex.

__Problem:__ How many faces, edges and vertices are in a cylinder?

Solution:

**If the cylinder is a solid object, then**

The cylinder has three faces - two circular faces at the two ends and the third a curved face.

It has 2 edges, both curved at the two ends.

It has no vertex.

**If the cylinder is a hollow object, like a pipe**

The cylinder has two faces - one internal and the other external.

It has 2 edges, both curved at the two ends.

It has no vertex.

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