(Product number: HFC3)
A sturdy base board, supports a circular table above the bench top. The table supports a large protractor and central pin. Around the edge of the table can be secured movable pulleys. These pulleys can be secured at varying angles. Cords run over the pulleys and secure to a central ring, and Load hanger. The central ring sits over the central pin when the loads are being applied to the hangers. When the central ring is removed from the central pin, the system rests in its equilibrium position, and the lines of action of the forces are recorded by drawing along the weighted cords onto a piece of paper attached to the pulley table.
The loads are applied using the hangers and cords provided, with the cords easily connecting to the shapes by the use of the small hooks provided.
Two additional shapes are provided to expand the student learning into link polygons for three or more non-concurrent coplanar forces.