Gere & Goodno — Axially Loaded Members: Problem 2.7-6

2.7-6 The truss \(ABC\) shown in the figure is subjected to a horizontal load \(P\) at joint \(B\). The two bars are identical with cross-sectional area \(A\) and modulus of elasticity \(E\). (a) Determine the strain energy \(U\) of the truss if the angle \(\beta = 60^\circ\). (b) Determine the horizontal displacement \(\delta_B\) of joint \(B\) by equating the strain energy of the truss to the work done by the load.