Page 625 - (DK) The Ultimate Visual Dictionary 2nd Ed.
P. 625

S hape S
          Shapes: Solid




          Three-dimensional shapes are known as solid shapes and                      surface areas and
          include spheres, cubes, and pyramids. A solid shape with a                       Volumes
          polygon at each face is called a polyhedron.                               Volume refers to the
                                                                                     amount of space that a
                                                                                     solid object occupies. Its
                                                                                     surface area is the sum of
                                                                                     the area of each of its faces.




                                                                                             h



               tetrahedron                 cube                  octahedron                     r
           A four-sided polyhedron. A   A regular hexahedron.   A polyhedron with
          regular tetrahedron is shown.   All sides are equal and   eight sides.
                                       all angles are 90º.
                                                                                            cylinder
                                                                                          Surface area =
                                                                                        2 x π x r x h + 2πr 2
                                                                                        Volume = π x r  x h
                                                                                                   2
                                                                                            Height = h
                                                                                            Radius = r




                   prism                  pyramid                   torus
            A polyhedron of constant   A polygonal base and   A doughnutlike, ring shape.          l
             cross-sections in planes   triangular sides that meet                           h
              perpendicular to its        at a point.
               longitudinal axis.
                                                                                                  r


                                                                                              cone
                                                                                          Surface area =
                                                                                          π xr x l + πr 2
                                                                                                     2
                                                                                      Volume = ⅓ x π x r  x l
                                                                                            Height = h
                  sphere                 hemisphere               spheroid                  Radius = r
             A round shape, as in a   Formed when a sphere   An egg-shaped solid object      Side = l
              ball or an orange.      is cut exactly in half.   whose cross-section is a circle
                                                                  or an ellipse.


                                                                                                       a
                                                                                      c
                                                                                             b

                                                                                        rectangular block
                                                                                           Surface area =
                   cone                right cylinder               helix              2 (a x b + b x c + a x c)
             An elliptical or circular   A tube-shaped, solid   A twisted curve. The    Volume = a x b x c
           base with sides tapering to a   figure. A right cylinder has   distance moved in one
                single point.            parallel faces.       revolution is its pitch.    Sides = a, b, c
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   US_622-623.indd   623                                                                             19/05/11   6:53 PM
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