The unsymmetrical $I-$section shown in Fig. $9\mathrm{.}16$ is subjected to a bending moment of $70$ kN $-$m$.$

Draw the variation of bending stress across the section.

$[$Ans$.$ Stress at top $=144\frac{N}{m}{m}^2,$ stress at bottom $=102\mathrm{.}86\frac{N}{m}{m}^2]$

$[$Note: $I=6\mathrm{.}80533{10}^{6}m{m}^4,y_b=100mm]$