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(d) Cylinder (iv)

(e) Square Pyramid (v)

(f) Tetrahedron (vi)

3. With the help of given figure of cube, answer the following questions. H
(a) Which edge is the intersection of faces EFGH and EFBA? G
(b) Which faces intersect at edge FB? E F
(c) Which three faces form the vertex A? C
(d) Which vertex is formed by the faces ABCD, ADHE and CDHG? A D B
(e) Write all the edges that are parallel to edge AB.
(f) Give all the edges that are perpendicular to edge AB.
4. Since the opposite faces of a die always have
a total of seven dots on them. Here are three 1 1 2
nets to make dice; the numbers inserted in each 2 3 4 5 3
square indicate the number of dots in that box.
6
Fill in the suitable numbers in the blanks,
remembering that the number on the opposite faces should have a total 7.
5. A cube has 6 faces. But the given figure shows the incomplete net of a cube.
Complete it in two different ways.
6. Draw a net of a cuboid having same breadth and height, but length double the breadth.

Drawing Solids on a Flat Surface

When we see the pictures of some 3D objects like moving cars, walking lions, running tigers, or a
sketch of a buildings on a paper, then we have visual illusion and due to this on a 2-dimensional
plane, they appear to be three-dimensional. Here, we will learn how to draw solids on a flat surface.
There are two methods that help us to draw a 3D object on a 2D surface like paper.
(1) Oblique sketch (2) Isometric sketch

Oblique Sketches

An oblique sketch is drawn on squared (lines or dots) paper. It gives a clear idea of how the solid
object looks like when seen from the front. Let us draw an oblique sketch for a cube of 3 units.
Step 1: Draw the front face by making a Step 2: Draw the opposite face. The sizes of
square of 3 units. the faces have to be same, but the sketch is
somewhat off-set from step 1.

265 Visualising Solid Shapes