Question 2.1: A bar having two different cross sectional areas is loaded b......

As it is clear from Figure 2.15 that the portions AB and BC of the bar are in tension and tensile stresses will prevail in them.

Normal stress in portion AB =\sigma_{ AB }=\frac{P}{A}

\begin{aligned} & =\frac{100 \times 10^3}{\left(\pi \cdot 25^2\right) / 4} \\ & =203.71  N / mm ^2 \end{aligned}

Normal stress in portion BC =\sigma_{ BC }=\frac{P}{A}

\begin{aligned} & =\frac{100 \times 10^3}{\left(\pi \cdot 40^2\right) / 4} \\ & =79.57  N / mm ^2 \end{aligned}