고체역학 (Gere) — Axially Loaded Members: Problem 2.3-21

2.3-21 A slightly tapered bar \(AB\) of solid circular cross section and length \(L\) is supported at end \(B\) and subjected to a tensile load \(P\) at the free end \(A\). The diameters of the bar at ends \(A\) and \(B\) are \(d_A\) and \(d_B\), respectively. Determine the length of the bar if the elongation of the bar due to the load \(P = 200 \text{ kN}\) is \(0.5 \text{ mm}\). Assume that \(E = 72 \text{ GPa}\). (From figure: \(d_A = 100 \text{ mm}\), \(d_B = 200 \text{ mm}\))