Page 216 - Maths Skills - 7

214 Maths

NETS OF SOLIDS
A net of a solid is another way of representing a 3D solid on a 2D surface.
It is the arrangement of faces of a solid in such a manner that they can form
a solid when folded or glued together.

Net of a cube
Fig. (a)

Draw 6 squares of equal dimensions as shown in the Fig. (a) and fold it from the edges shown as dotted lines. You
will get a cube.
A A
l
b h

B C
Step 1 Step 2 Step 3 B C
Net of a cuboid Net of a cone
Fig. (b) Fig. (c)

Net of a cylinder Net of a prism
Fig. (d) Fig. (e)

Net of a square pyramid Net of a triangular pyramid

Fig. (f) Fig. (g)

VISUALISING SOLIDS
A 3D object can be visualised in various ways.

By Cutting or Slicing the Solid
Let us take an example of an ice cream brick which after being given a vertical
cut gives a square face. This is called a cross-section.
Square
Vertical cut

When the same ice cream brick is given
a horizontal cut, we get a rectangular
Rectangle face this time.
Horizontal cut