Types of Polyhedrons

Q.

What are convex polyhedrons?

Q.

Draw a net of a triangular pyramid.

Q. Match the nets with the appropriate solids: [4 MARKS]

Q.

Question 63 (iv)

How many faces does the following solid have?

Octahedron

Q.

Which among the figures is not a convex polyhedron?

1. 

2. 

3. 

4. 

Q.

Question 81

Complete the table given below by putting tick mark across the respective property found in the solids mentioned.
$\begin{array}{cccccc}& \text{Properties}& \text{Cone}& \text{Cylinder}& \text{Prism}& \text{Pyramid}\\ 1.& \text{The figure is a polyhedron.}& & & & \\ 2.& \text{The figure has diagonals.}& & & & \\ 3.& \text{The shape has curved edges.}& & & & \\ 4.& \text{The base of figure is a polygon.}& & & & \\ 5.& \text{The bases are congruent.}& & & & \\ 6.& \text{The base of figure is a polygon and other}& & & & \\ & \text{faces meet at a single point.}& & & & \\ 7.& \text{The base of figure is a curved edge and other}& & & & \\ & \text{faces meet at a single point.}& & & & \end{array}$

Q. Question 45

State whether the following statement is True or False.

Regular octahedron has 8 congruent faces which are isosceles triangles.

Q. Which of the following is not a prism?

1. 
2. 
3. 
4. 

Q. Polyhedrons that are made up of convex polygons are called

1. non-convex polyhedron
2. concave polyhedron
3. non-concave polyhedron
4. convex polyhedron

Q.

What is the least number of planes that can / enclose a solid? What is the name of the solid.

Q.

Which among the figures is not a convex polyhedron?

1. 

2. 

3. 

4. 

Q.

Question 63 (i)

How many faces does the following solid have?

Tetrahedron

Q. Name the regular polyhedron.

1. octahedron
2. tetrahedron
3. dodecahedron
4. icosahedron

Q. The end on which a prism may be supposed to stand is called ___ of the prism.

1. base
2. height
3. length
4. side

Q. In which polyhedron, any plane section is a convex polygon?

1. convex polyhedron
2. concave polyhedron
3. non-convex polyhedron
4. non-concave polyhedron

Q. The following figure represents a

1. Polygon
2. Cylinder
3. Convex polyhedron
4. None of these

Q.

Name the solids whose nets are shown below:

Q. In the above figure, if only the shaded cubes are visible from the top, draw the base layer.

Q. Solid Geometry. Problems on Proof.
Prove that two triangular pyramids are equal or symmetric; if their respective edges are equal.

Q. Write down the number of faces of each of the following figures:
(i) Cuboid
(ii) Cube
(iii) Triangular prism
(iv) Square pyramid
(v) Tetrahedron

Q. A icosahedron has ........... faces.

Q.

how many faces does Icosahedron has?

Q.

What is the least number of planes that can enclose a solid? What is the name of the solid?

Q. How many faces does a solid with 5 vertices and 10 edges have?

1. 5
2. 3
3. 12
4. 7

Q.

Which among the figures is not a convex polyhedron?

1. 

2. 

3. 

4. 

Q. The end on which a prism may be supposed to stand is called ___ of the prism.

1. base
2. height
3. length
4. side

Q.

Draw nets for each of the following polyhedrons:

Q. Which are prisms among the following?

Q. All platonic solids are

1. regular polyhedron
2. concave polyhedron
3. convex polyhedron
4. irregular polyhedron

Q. Which of the following is the other name of a cube?

1. Square antiprism
2. Cuboctanedron
3. Tetrahedron
4. Regular hexahedron