# Visualising Solid Shapes Chapter 15 Class 7 Maths NCERT Textbook With Solutions PDF

NCERT Solutions for Class 7 Maths Chapter 15′ PDF Quick download link is given at the bottom of this article. You can see the PDF demo, size of the PDF, page numbers, and direct download Free PDF of ‘Ncert Class 7 Maths Chapter 15 Exercise Solution’ using the download button.

### Chapter 15: Visualising Solid Shapes

the concepts discussed in this chapter.

• Introduction to Plane Figures and Solid Figures
• Faces, Edges and Vertices
• Nets for Building 3-D Shapes
• Drawing Solids on a Flat Surface
• Oblique Sketches
• Isometric Sketches
• Visualising Solid Objects
• Viewing Different Sections of a Solid
• One way to View an Object By Cutting or Slicing
• Another Way is By Shadow Play

#### 15.1 INTRODUCTION: PLANE FIGURES AND SOLID SHAPES

In this chapter, you will classify figures you have seen in terms of what is known as dimension.

In our day-to-day life, we see several objects like books, balls, ice-cream cones, etc., around us which have different shapes.

One thing common about most of these objects is that they all have some length, breadth, and height or depth.

That is, they all occupy space and have three dimensions. Hence, they are called three-dimensional shapes. Do you remember some of the three-dimensional shapes (i.e., solid shapes) we have seen in earlier classes?

#### 15.4 DRAWING SOLIDS ON A FLAT SURFACE

Your drawing surface is paper, which is flat. When you draw a solid shape, the images are somewhat distorted to make them appear three-dimensional. It is a visual illusion.

You will find here two techniques to help you. 15.4.1 Oblique Sketches Here is a picture of a cube (Fig 15.11). It gives a clear idea of what the cube looks like, Fig 15.11 when seen from the front. You do not see certain faces.

In the drawn picture, the lengths are not equal, as they should be in a cube. Still, you are able to recognize it as a cube. Such a sketch of a solid is called an oblique sketch.

How can you draw such sketches? Let us attempt to learn the technique. You need squared (lines or dots) paper.

Initially practicing to draw on these sheets will later make it easy to sketch them on a plain sheet (without the aid of squared lines or dots!) Let us attempt to draw an oblique sketch of a 3 × 3 × 3 (each edge is 3 units) cube (Fig 15.12).

### NCERT Solutions Class 7 Maths Chapter 15 Visualising Solid Shapes

Q2. The dimensions of a cuboid are 5 cm, 3 cm and 2 cm. Draw three different
isometric sketches of this cuboid.

Q3. Three cubes each with 2 cm edge are placed side by side to form a cuboid.
Sketch an oblique or isometric sketch of this cuboid.

Q5. Give (i) an oblique sketch and (ii) an isometric sketch for each of the
following:
(a) A cuboid of dimensions 5 cm, 3 cm and 2 cm. (Is your sketch unique?)
(b) A cube with an edge 4 cm long.
An isometric sheet is attached at the end of the book. You could try to make
on it some cubes or cuboids of dimensions specified by your friend.