Plane and Solid Geometry

ISBN: 9781334014338 出版年：2016 页码：492 George Wentworth David Eugene Smith Forgotten Books

That is, a physical solid can be touched and handled; a geometric solid is the space that a physical solid is conceived to occupy. For example, a stick is a physical solid but if we put it into wet plaster, and then remove it, the hole that is left may be thought of as a geometric solid although it is filled with air.