Recognition of Solids
ICSE Class 6 · Mathematics · Chapter 31
What this chapter covers
- Solid shapes around you
- Faces, edges and vertices
- Cube, cuboid, cylinder, sphere and cone
- Prisms and pyramids
- Nets of solids
Key points
- A solid has length, breadth and height and takes up space; a plane figure is flat.
- A face is a surface of a solid, an edge is where two faces meet, and a vertex is a corner point or the sharp tip of a cone.
- A cube and a cuboid each have 6 faces, 12 edges and 8 vertices.
- A cylinder has 3 faces, 2 edges and no vertex; a cone has 2 faces, 1 edge and 1 vertex.
- A sphere has 1 curved face and no edge or vertex.
- A triangular prism has 5 faces, 9 edges and 6 vertices; a square prism is like a cuboid.
- A triangular pyramid (tetrahedron) has 4 faces; a square pyramid has 5 faces.
- A net is a flat shape that folds into a solid, with each face appearing once.
- Nets: cube (6 squares), cuboid (6 rectangles), cylinder (rectangle and 2 circles), cone (a curved slice and a circle), tetrahedron (4 triangles).
Questions answered
Name the solid shape of a brick.
A cuboid.
How many faces, edges and vertices does a cube have?
6 faces, 12 edges and 8 vertices.
Which solid has no edge and no vertex? Give one example.
A sphere, such as a football or a marble.
A candle is shaped like a cylinder. How many flat faces and how many curved faces does it have?
2 flat faces and 1 curved face.
What is the other name of a triangular pyramid, and how many faces does it have?
A tetrahedron. It has 4 faces, all triangles.
Rohan says a square pyramid has 4 faces. Is he right?
No. It has 5 faces: 1 square base and 4 triangular faces.
What shapes make up the net of a cylinder?
One rectangle and two equal circles.
Name the solid shape of a camping tent and count its edges.
A triangular prism. It has 9 edges.