Hi students, welcome to **Amans Maths Blogs (AMB)**. On this page, you will get the short notes and important question of **CBSE Class 8 Chapter 10 Visualizing Solid Shapes**. These short notes and important questions are taken from the NCERT text books and other books. If you want to get the **NCERT Solution for class 8 Maths Visualizing Solid Shapes Chapter**, then **click here**. If you need sample questions based on visualizing solid shapes for practice, then you are at right place.

Contents

# SHAPES

Geometrical figures are known as shapes. There are three types of shapes.

One Dimensional shape: Line

Two Dimensional shape: Rectangle cancel etc.

Three Dimensional shape: Polyhedron etc.

# POLYHEDRON

A solid shape bounded by the polygons is called Polyhedron. The plural word for polyhedron are Polyhedron, polyhedrons or polyhedral. Polyhedrons are described by three components

Faces: polygons forming a polyhedron are known as faces.

Edges: the line segments formed by the intersection of two faces of a polyhedron known as Edges.

Vertices: the points of intersection of edges of a polyhedron are known as vertices.

Figure

# EULER’S FORMULA

A formula which relates the number of faces (F)the number of vertices (V) and the number of edges (E) of a polyhedron is known as Euler’s Formula. Thus, F + V = E + 2 or F + V – E = 2.

In cube, F = 6, V = 8, E = 12. Thus, F + V – E = 6 + 8 -12 = 2 Hence, cube is a polyhedron.

The Euler’s formula is only for polyhedrons, not for non- polyhedrons like cylinder cone etc.

# NON–POLYHEDRONS

The solids which are not made of polygons are known as Non-polyhedrons.

Example:

Figure

Now polyhedrons are of two types: convex polyhedrons and concave polyhedrons.

# CONVEX POLYHEDRONS S CONCAVE POLYHEDRONS

If the line segment joining any two ports on the surfaces of a polyhedron entirely lies aside or on the polyhedron, then it is said to be a convex polyhedron otherwise it is known as concave polyhedron.

Figure 2

# REGULAR’S IRREGULAR POLYHEDRONS

A polyhedron is a regular polyhedron if its faces are formed by the regular polygons and the same number of meet at each vertex. otherwise, it is an irregular polyhedron.

Figure 2

# PRISM

A prism is a solid whose faces are parallelograms and the ends are congruent parallel two Dimensional’s shapes A prism has both and congruent polygon (two dimensional figures). Now, the prism are of two types.