Homework 1 1. The following data are collected during a tensile test in which the starting gage length = 125.0 mm and the cross- sectional area = 62.5 𝑚𝑚2 :

Homework 1 1. The following data are collected during a tensile test in which the starting gage length = 125.0 mm and the cross- sectional area = 62.5 𝑚𝑚2 : Load (N) 0 17,793 23,042 27,579 28,913 27,578 20,462 Length (mm) 0 125.23 131.25 140.05 147.01 153 160.10 The maximum load is 28,913 N and the final data point occurred immediately prior to failure. (a) Plot the engineering stress strain curve. Determine: (b) yield strength Y, (c) modulus of elasticity E, (d) tensile strength 𝑇𝑆 . 2. Derive an expression for true strain as a function of D and Do for a tensile test specimen of round cross-section. Given: V = AoLo = AL ; A = 𝐷 2 3. Show that true strain = ln(1 + e).