Which amongst the following is not a polyhedron?
(a) 
(b) 
(c) 
(d) 

Solution:

We have to find a figure which is not a polyhedron.

A solid is a polyhedron if it is made up of only polygonal faces, the faces meet at edges which are line segments and the edges meet at a point called vertex.

We observe that the figures in option a, b and d, consist of faces, vertices and edges.

In figure c, the faces are not polygons and there is a circular base.

It is a two dimensional figure.

Therefore, the figure c is not a polyhedron.

✦ Try This: Which amongst the following is not a polyhedron?

(a) 

(b) 

(c) 

(d) 

☛ Also Check: NCERT Solutions for Class 8 Maths Chapter 10

NCERT Exemplar Class 8 Maths Chapter 6 Problem 1

Which amongst the following is not a polyhedron?

Summary:

Option (c) is not a polyhedron.

☛ Related Questions:

• Which of the following will not form a polyhedron? (a) 3 triangles, (b) 2 triangles and 3 parallelog . . . .
• Which of the following is a regular polyhedron? (a) Cuboid, (b) Triangular prism, (c) Cube, (d) Squa . . . .
• Which of the following is a two Dimensional figure? (a) Rectangle, (b) Rectangular Prism, (c) Square . . . .