Solution to Problem 105 | Normal Stress

By symmetry:
$P_{br} = P_{st} = \frac{1}{2}(7848)$

$P_{br} = 3924 \, \text{ N}$

$P_{st} = 3924 \, \text{ N}$
 

 

For bronze cable:
$P_{br} = \sigma_{br} A_{br}$

$3924 = 90 \, A_{br}$

$A_{br} = 43.6 \, \text{mm}^2$           answer
 

For steel cable:
$P_{st} = \sigma_{st} \, A_{st}$

$3924 = 120 \, A_{st}$

$A_{st} = 32.7 \, \text{mm}^2$           answer