• 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.

The apparatus includes a free standing back plate mounted on a worktable, 3 wires at different angles, load hangers, weight and a universal ring. Wire suspension scheme is used to verify the equilibrium where sum of horizontal and vertical forces are zero.

Three wires attached at 45 degree; 60 degree and 90 degree meet at common ring. Load hanger is attached to the universal ring. Each wire includes a linear spring balance to get the value directly. Length of each suspender can be adjusted with the help of threaded rod attached to the spring balance. Known weights are available to apply load to the wires.