… for cables#

The differential equation for equilibrium relations for cables is based on the infinitesimal small loaded cables:
leading to :
\[{q_z} = - \frac{{{d}V}}{{{d}x}}\]
\[{V} = H\frac{{{d}z}}{{{d}x}}\]
This is treated in chapter 14.1.3 of the book Engineering Mechanics Volume 1 (Hartsuijker and Welleman, 2006).