The rat trap shown in the figure uses two opposite-image torsion springs. The wire has a diameter of 0.081 in, and the outside diameter of the spring in the position shown is ½ in. Each spring has 11 turns. Use of a fish scale revealed a force of about 8 lbf is needed to set the trap.
(a) Find the probabable configuration of the spring prior to assembly.
(b) Find the maximum stress in the spring when the trap is set.