Table of contents  
Plane Figures and Solid Shapes  
Faces, Edges and Vertices of 3D Shapes  
Nets for Building 3D Shapes  
Drawing Solids on a Flat Surface  
Viewing Different Sections of a Solid 
Look at the picture of the pencil box given below. You can only see its length and width. This picture would be a 2D image because it has only two dimensions: length and width. It's like looking at a flat drawing of your pencil box on a piece of paper.
Now, if you could see your pencil box from all sides, including the top, bottom, front, back, and sides, you would have a 3D image. A 3D image shows all three dimensions: length, width, and height. It's like holding your pencil box in your hands and being able to see it from every angle.
In simple terms, a 2D image is like a flat drawing, and a 3D image is like seeing the real object in front of you.
Visualizing solid shapes is an essential concept in mathematics, particularly in geometry. Solid shapes, also known as threedimensional (3D) shapes, exist in physical space and have three dimensions: length, width, and height. Unlike twodimensional shapes, such as squares and circles, which exist on a flat plane, solid shapes have volume and occupy space.
The table shows the number of the faces, edges and vertices of some shapes.
The net of a threedimensional solid is a twodimensional skeleton outline, which, when folded, results in the threedimensional shape. Net is used for making 3D shapes.
Nets of 3D Shapes
There are two techniques to create the illusion, of threedimensionality when drawing solid shapes on a flat surface, such as paper.
There are many methods to view different sections of a solid:
(a) Slicing and Cutting: This method reveals the inside of a solid by slicing it into crosssections.
(b) Shadow Casting: This technique creates a twodimensional representation of a threedimensional object by casting its shadow.
(c) Viewing from Different Angles: Observing a solid from various perspectives, such as front, side, and top views, offers valuable insights into its shape and structure.
Example: Different viewpoints of a building are illustrated below.
76 videos345 docs39 tests

1. What are the main components of a 3D shape? 
2. What is a net in relation to building 3D shapes? 
3. How can one draw solids on a flat surface? 
4. How can one view different sections of a solid shape? 
5. What is the importance of visualizing solid shapes in mathematics? 

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