Tag Archives: Force

Crane Rigging Angles


 Model Description This demonstration depicts the importance of rigging angles during crane lift operations on a construction site.  Reducing rigging angles results in a significant amplification of forces in the rigging, potentially leading to failure.  By varying the connection points and sling length, students will be able to calculate the predicted forces and analyze the […]

Zero Force Members


 Model Description This is a simple model that will demonstrate the use of zero force members (ZFM) in trusses. Wooden beams are attached with dowels to form a simple truss, which is acted on by an external force. The zero force members are identified by placing a load on a truss and then removing pins […]

Varignon’s I-Beam


 Model Description Introduce Varignon’s theorem to students as a simple way to determine the moment about a point. This demonstration should take 5-7 minutes. Engineering Principle Varignon’s Theorem states that the moment of a force is equal to the sum of the moments of that force’s components about the same point. where is the perpendicular […]

The Persuader


 Model Description Use this daunting looking model to set the stage for a lesson on 3-D equilibrium and eventually persuade your students that it’s easier than it looks!  This demonstration should take 20 minutes. Engineering Principle 3-D equilibrium for a non-concurrent force system requires the simultaneous solution of six equations of equilibrium, three equations for […]

Frame Demos


 Model Description Introduce the concept of a frame and use a good free body diagram and the equations of equilibrium to solve for the forces and reactions acting on the frame.  This demonstration should take 5-10 minutes. Engineering Principle Frames and Machines are one way to classify a structure.  As opposed to Trusses, Frames and […]