POINTS TO REMEMBER RELATED TO
THREE DIMENSIONAL SHAPES :
CLASS 5TH, 6TH, 7TH, 8TH, 9TH & 10TH
READ : REPEAT : LEARN
MUST KNOW THESE POINTS :
1) An object that occupies space is called a solid.
2) Shapes of solids are known as three – dimensional shapes.
CUBOID
3a) A cuboid has length, breadth and height.
b) A cuboid has 6 rectangular faces, 12 edges and 8 vertices.
c) A matchbox, a chalk box, a brick are examples of a cuboid.
CUBE
4a) A cube has equal length, breadth and height.
b) A cube has 6 square faces, 12 edges and 8 vertices.
c) Ice cubes, sugar cubes, dice are examples of a cube.
CYLINDER
5a) A cylinder has a curved lateral surface and two circular faces at its ends.
b) It has no corner or vertex.
c) It has two plane faces , namely, the top and the bottom and one curved face.
d) It has two circular edges.
e) The distance between its two end faces is called its length.
f) Objects like circular pillar, a circular pipe, a measuring jar, a gas cylinder, a test tube are
examples of a cylinder.
SPHERE
6a) Objects in the shape of a ball are known as spheres.
b) A sphere has a curved surface only.
c) It has no vertex and no edge.
CONE
7a) A cone has a plane circular end as the base and a curved surface tapering into a point called
its vertex.
b) It has one plane face and one curved face.
c) It has one circular edge and one vertex.
d) Objects like conical tent, ice- cream cone , conical vessel are examples of cone.
TRIANGULAR PRISM
8a) A solid with rectangular lateral faces and congruent triangles as bases is called a triangular
prism.
b) It has 6 vertices, 3 rectangular faces, 2 triangular bases and 9 edges.
SQUARE PYRAMID
9a) A solid whose base is a square and whose side faces are triangles having a common vertex
is called a square pyramid.
b) It has 4 lateral triangular faces and 8 edges.
TRIANGULAR PYRAMID
10a) A solid whose base is a triangle and side faces are triangles having a common vertex is
called a triangular pyramid.
b) It has 3 triangular lateral faces, one triangular base and 6 edges.