$$ \begin{array}{l}{\text { Data } : \mathrm{P}=6 \mathrm{kN} \quad \sigma=110 \mathrm{N} / \mathrm{mm}^{2}} \ {\text { Find: } \mathrm{d}_{\min }=?} \ {\sigma_{\max }=\frac{p_{\max }}{A_{\min }}} \ {A_{\min }=\frac{p_{\max }}{\sigma_{\min }}}\end{array} $$ $$ \begin{array}{l}{A_{\min }=\frac{6 \times 10^{3}}{110}=54.54 m m^{2}} \ {\frac{\pi}{4} \times d^{2} \min =54.54 m m^{2}} \ {d^{2} \min =54.54 \times \frac{4}{\pi}=69.442}\end{array} $$ $$ d_{\min }=8.33 m m $$