Page 223 - ICSE Math 7

(d) The number of edges in the given solid is ______________.
(i) 12 (ii) 14
(iii) 16 (iv) 18

(e) The number of unit cubes present in
the combination is ______________.
(i) 20 (ii) 21
(iii) 19 (iv) 13

2. Write True or False. Side
(a) The shadow of a 3D object is 2 dimensional. Front

(b) The net of a solid is unique.
(c) If a right-angled triangle is revolved around one of its legs, a cone is generated.
(d) A cylinder has 2 faces.
(e) In an isometric sketch, line segments of different lengths can represent the sides of a cube.

3. Fill in the blanks.
(a) The base of pyramid is a and its other faces are
having a common vertex.
(b) The two faces of a solid meet to form an .

(c) A point where three or more faces meet is called a .
(d) A solid that has congruent and parallel polygons as top and base joined by rectangular faces
is known as .
(e) A solid having no vertex and no edge is a .

(f) A pyramid having 4 equilateral triangles as its faces is called a .
(g) A polyhedron having 20 faces and 12 vertices will have edges.

PRACTICE TIME

1. Which of these nets will make a square pyramid? Verify by tracing, cutting and folding the
shape.

(a) (b) (c) (d) (e)

2. Draw isometric sketches of the following shapes.

(a) (b)

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