Question

A prismatic bar with rectangular cross-section (25mmX45mm) and length 3m is subjected to an axial tensile force of 70KN. The measured deformation of the bar is 1.2mm. Calculate the tensile stress and strain in the bar.

Answer 1

The stress

$$\sigma=\frac{F}{A}=\rm\frac{70\;000\: N}{0.025\: m\times 0.045\: m}=6.2\times 10^7\: Pa$$

The strain

$$\varepsilon=\frac{\Delta L}{L_0}=\rm\frac{0.0012\: mm}{3 \: m}=0.0004$$