Author Archives: homadmin

Ruler Truss

 

 Model Description This demonstration shows the simplicity of a truss. The equipment consists of a single triangle made of two rulers and string – forming a truss. The truss is held on two desks by students and given a load by another student. This shows the innate strength of the simple triangular shape used in […]

Pulleys: The Equilibriator Challenge!

 

 Model Description This is a simple demonstration of the mechanical advantage associated with pulleys and a solution method for pulley problems.  By building a pulley system in the classroom, students can gain a physical appreciation for the problem at hand.  This demonstration should take 15-20 minutes. Engineering Principle This training aid demonstrates mechanical advantage obtained […]

Moments and Couples

 

 Model Description Introduce the concept of Moment and couples to your students by providing hands-on examples that they can relate to.  Demonstrate how levers use the concept of moment to provide a mechanical advantage.  This demonstration should take 5-10 minutes. Engineering Principle The Moment caused by a force about any point is defined by the […]

Lug Wrench vs. Breaker Bar

 

 Model Description Introduce Varignon’s theorem to students as one way to determine the moment about a point.  Show how moments are free vectors. This demonstration should take 10 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 […]

Fun with Friction

 

 Model Description Investigate slipping and tipping for Coulomb Friction.  This demonstration should take 5-10 minutes. Engineering Principle These training aids provide a vehicle to discover the need to consideration three possibilities when investigating friction problems: 1) Nothing happens 2) Slipping occurs, 3) Tipping occurs. What You Need Item Quantity Description/Clarification Ramp 1 A board or […]

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 […]

Distributed Student Loading

 

 Model Description This model will get your students on their feet during class and help them visualize the concept of distributed loading. This demonstration should take 5-7 minutes. Engineering Principle In order to get students to begin to get a feel for load transfer and modeling loading, it is helpful to show an example. This […]

Belt Friction

 

 Model Description Investigate belt friction.  This demonstration should take 3-5 minutes. Engineering Principle These training aids provide a vehicle to discover the forces acting on a belt or rope when pulled over a fixed drum. The basic equation for belt friction: where coefficient of friction (either static or kinetic and angle of surface contact between […]

Amazing Weight Loss Program

 

 Model Description This is a simple and rapid demonstration of the perpendicular and parallel components of a force vector on an inclined plane.  By weighing a student or instructor first on the floor and then at some inclination, a “loss of weight” is observed.  This demonstration should take 5-8 minutes. Engineering Principle Spring scales are […]

K’NEX Trusses

 

 Model Description This simple pair of K’NEX models can demonstrate how trusses greatly increase the strength/stiffness of structures without adding much weight. The trusses are built out of K’NEX pieces and topped with construction paper to produce a roadway. Text books are used to load the trusses to demonstrate its strength to weight ratio.  This […]