• To study the vertical equilibrium of a two and three wire suspension system.
  • To examine the action of the central vertical redundant force.


  • Verification of equilibrium where sums of horizontal and vertical forces are zero; investigate redundancy of vertical tie in a three wire suspension system.
  • The apparatus consists of a bench mounted free standing backboard with 3 wires attached at approx. 45 degrees, 60 degree and 90 degree to the horizontal and all meeting at a common ring.
  • Load hanger attached to the common ring to load the system.
  • Each wire incorporates a direct reading, linear spring balance to measure its tension.
  • An instruction manual for student and lecturer provided.
  • Set of weights.

This apparatus consists of a free standing block that is mounted on a worktable. Within the free standing block, there are 3 wires attached at different angles, weight ring and a universal ring and some load hangers. The three wires are attached in a 45*, 60* and 90* to the user. The wires meet at the weight ring. A wire suspension scheme is used to verify the equilibrium when the sum of horizontal and vertical forces is zero. Each wire is also installed with a linear spring to get value of extension due to load individually. The length of each suspender can be adjusted with the help of threaded rod attached to a spring balance. The load hanger is attached to the universal ring and known weights are available to apply load to the wires.