The figure shows a compound axial member consisting of a larger cylindrical segment A B which is marked 1 having a length of 1800 millimeters flanged to another cylindrical segment B C which is marked 2 having a length of 800 millimeters. Segment 1 is fixed to a wall at the point A. The x axis is taken along the common axis of the two cylindrical members and the y axis is taken perpendicular to the x axis along the wall. The tension load at the free end of segment 2 is P which equals 50 kilo newtons oriented in the positive x direction.

The maximum elongation that is acceptable for segment (2) is δ2=2.14 mm. Rearrange the axial force-deformation equation to solve for the minimum acceptable area A2.

A2=π4d2

d2=4πA2=4π(267.02 mm2)=339.98 mm2

d=18.44 mm