Shape 

Copyright David & Cynthia Thomas, 2009

 

Visualizing 3-Dimensional Objects--Directed Activity: Slicing Platonic Solids

                                          

Focus

2-Dimensional Slices of the Platonic Solids

Technologies

·        Platonic Solids-Slicing model (See Figure 6.7) at the National Library of Virtual Manipulatives (NLVM) website.

Background

In Flatland, the hero of the story couldn’t imagine the intersection of a 2-dimensional plane with a 3-dimensional sphere.  Try your luck imaging the intersection of a 2-dimensional plane with the Platonic Solids. 

Figure 6.7: NLVM Platonic Solids-Slicing Model

Tasks

Using the NLVM model Platonic Solids-Slicing, investigate the 2-dimensional shapes created when a plane intersects each solid.  For each Platonic Solid, list the fundamental shapes obtained (e.g., triangle, trapezoid, parallelogram, and so on) and which, if any, of the regular polygons appear as cross sections.