Visualising Solid Shapes
Class 8th Mathematics CBSE Solution
- For each of the given solid, the two views are given. Match for each solid the…
- For each of the given solid, the three views are given. Identify for each solid…
- For each given solid, identify the top view, front view and side view A. B. C.…
- Draw the front view, side view and top view of the given objects. A. A military…
- Look at the given map of a city Answer the following. A. Color the map as…
- Draw a map of your class room using proper scale and symbols for different…
- Draw a map of your school compound using proper scale and symbols for various…
- Draw a map giving instructions to your friend so that she reaches your house…
- Can a polyhedron have for its faces (i) 3 triangles? (ii) 4 triangles? (iii) A…
- Is it possible to have a polyhedron with any given number of faces? (Hint:…
- Which are prisms among the following? (i) (ii) (iii) (iv) infinity…
- (i) How are prisms and cylinders alike? (ii) How are pyramids and cones alike?…
- Is a square prism same as a cube? Explain
- Verify Eulers formula for these solids. (i) m (ii) delta
- Using Eulers formula find the unknown Faces ? 5 20 Vertices 6 ? 12 Edges 12 9 ?…
- Can a polyhedron have 10 faces, 20 edges and 15 vertices?
Exercises 10.1
Question 1.For each of the given solid, the two views are given. Match for each solid the corresponding top and front views. The first one is done for you
Answer:
The matched respective side and top views are as follows:
Question 2.
For each of the given solid, the three views are given. Identify for each solid the corresponding top, front and side views
Answer:
(a)
(i) Front (ii) Side (iii) Top
(b)
(i) Side (ii) Front (iii) Top
(c)
(i) Front (ii) Side (iii) Top
(d)
(i) Front (ii) Side (iii) Top
Question 3.
For each given solid, identify the top view, front view and side view
A. 
B. 
C. 
D. 
E. 
Answer:
A.
(i) Top (ii) Front/Side (iii) Side/Front
B.
(i) Side (ii) Front (iii) Top
C.
(i) Top (ii) Side (iii) Front
D. 
(i) Side (ii) Front (iii) Top
E.
(i) Front/Side (ii) Top (iii) Side/Front
Question 4.
Draw the front view, side view and top view of the given objects.
A. A military tent 
B. A table 
C. A nut 
D. A hexagonal block
E. A dice 
F. A solid
Answer:
A. Military tent:
Front view:
Top view:
Side view:
B. Table:
Front view:
Top view:
Side view:
C. A nut
Front view:
Top view:
Side view:
D. A hexagonal block
Front view:
Top view:
Side view:
E. A dice
Front view:
Top View:
Side View:
F. A Solid
Top View:
Front View:
Side View:
Exercises 10.2
Question 1.Look at the given map of a city
Answer the following.
A. Color the map as follows: Blue-water, red-fire station, orange-library, yellow- schools, Green - park, Pink - College, Purple - Hospital, Brown - Cemetery.
B. Mark a green ‘X’ at the intersection of Road ‘C’ and Nehru Road, Green ‘Y’ at the intersection of Gandhi Road and Road A.
C. In red, draw a short street route from Library to the bus depot.
D. Which is further east, the city park or the market?
E. Which is further south, the primary school or the Sr. Secondary School?
Answer:
(a) The required colored map is as follows:
(b) Marks can be put in the following way:
(c) The shortest route of the given condition is as follows:
(d) The City Park is further east between the Market and the City Park
(e) Sr. Secondary School is further south between the Primary School and the Sr. Secondary School
Question 2.
Draw a map of your class room using proper scale and symbols for different objects
Answer:
Activity to individual students and they have to do by their own
1. Draw the layout of the classroom. i.e the outer portion of the classroom, with windows and doors and the type of roof.
2. Draw the various things in the classroom. Like Board, chairs, desks and other things present in the classroom.
Question 3.
Draw a map of your school compound using proper scale and symbols for various features like play ground main building, garden etc.
Answer:
Activity to individual students and they have to do by their own
Question 4.
Draw a map giving instructions to your friend so that she reaches your house without any difficulty
Answer:
Activity to individual students and they have to do by their own
Exercises 10.3
Question 1.Can a polyhedron have for its faces
(i) 3 triangles?
(ii) 4 triangles?
(iii) A square and four triangles?
Answer:
(i) No, such a polyhedron is not possible. A polyhedron has minimum 4 faces
(ii) Yes, a triangular pyramid has 4 triangular faces
(iii) Yes, a square pyramid has a square face and 4 triangular faces
Question 2.
Is it possible to have a polyhedron with any given number of faces? (Hint: Think of a pyramid)
Answer:
A polyhedron has a minimum of 4 faces
Question 3.
Which are prisms among the following?
(i) 
(ii) 
(iii) 
(iv) 
Answer:
(i) It is not a polyhedron as it has a curved surface. Therefore, it will not be a prism also
(ii) It is a prism
(iii) It is not a prism. It is a pyramid
(iv) It is a prism
Question 4.
(i) How are prisms and cylinders alike?
(ii) How are pyramids and cones alike?
Answer:
(i) A cylinder can be thought of as a circular prism i.e., a prism that has a circle as its base
(ii) A cone can be thought of as a circular pyramid i.e., a pyramid that has a circle as its base
Question 5.
Is a square prism same as a cube? Explain
Answer:
A square prism has a square as its base. However, its height is not necessarily same as the side of the square. Thus, a square prism can also be a cuboid
Question 6.
Verify Euler’s formula for these solids.
(i) 
(ii) 
Answer:
(i) Number of faces = F = 7
Number of vertices = V = 10
Number of edges = E = 15
We have,
F + V - E = 7 + 10 - 15
= 17 - 15
= 2
Hence, Euler's formula is verified
(ii) Number of faces = F = 9
Number of vertices = V = 9
Number of edges = E = 16
F + V - E = 9 + 9 - 16
= 18 - 16
= 2
Hence, Euler's formula is verified
Question 7.
Using Euler’s formula find the unknown
Answer:
By Euler's formula, we have
F + V - E = 2
(i) F + 6 - 12 = 2
F - 6 = 2
F = 8
(ii) 5 + V - 9 = 2
V - 4 = 2
V = 6
(iii) 20 + 12 - E = 2
32 - E = 2
E = 30
Thus, the table can be completed as:
Question 8.
Can a polyhedron have 10 faces, 20 edges and 15 vertices?
Answer:
Number of faces = F = 10
Number of edges = E = 20
Number of vertices = V = 15
Any polyhedron satisfies Euler's Formula, according to which, F + V - E = 2
For the given polygon,
F + V - E = 10 + 15 - 20
= 25 - 20
= 5 ≠ 2
Since Euler's formula is not satisfied, such a polyhedron is not possible