Beam Me Down : Cross Section Exploration
So just what did modern engineers start discovering around the end of the 19th century? First, we need to define some terms, and among those is Cross Section. The cross section of a beam (or any object) is the view you get if you look at a slice of the beam from the end. For example, wood used in house construction is measured in cross section, eg. a 2x4. The numbers indicate its size if you look at it from the end. And for a 2x4, which is solid, the simple exterior measurements completely define the cross section.
You can use the Beam Applet or Beam Activity or Beam activity with accessibility to experiment with drawing cross sections. The applet is a simplified drawing program in which you click to add squares, 'units', to the design, and click again to remove them.
Modern engineers developed and began using various formulas, many of which are now available for you, behind the scenes, in tools like the applet. Thanks to them, we no longer have to build large structures the same way the Egyptians and Romans did.