HW$2$:

You must use Thin$-$Walled approximation to get credit.

P$\mathrm{.}15\mathrm{.}5$ A thin$-$walled beam has the cross section shown in Fig. P$\mathrm{.}15\mathrm{.}5.$ If the beam is subjected to a bending moment $\backslash ($ M$\_\{$x$\}\backslash )$ in the plane of the web $23,$ calculate and sketch the distribution of direct stress in the beam cross section.

Assume the centroid of the section is at the mid$-$point of the web

Fig. P$.15\mathrm{.}5$