[SOLVED] Cables help please! Hi, I don't think this is really a 'homework' question but more of a theory related question. I am currently a self-learner on engineering statics and at the moment I am reading up on cable theory and analysis, in particular the catenary problem. I am not used to physically interpreting mathematical equations/data and was wondering if someone could be of help? Okay so basically, lets consider a perfect inextensible and flexible cable of length 2L, suspended by its ends from two supports B and B' a distance 2l apart and at the same height. We define c = T_o/mu (sorry I am not a use of Latex) and the equation for the catenary shape has been derived to be y = c cosh (x/c) after choosing A to be our lowest point of the cable as co-ordinate (0,c). Also by using the arc length formula we find the arc length s (from A to B) is s = c sinh (x/c) => L = c sinh (l/c) since from A to B = L and x = l What I don't understand is the next part where we have non-dimensional variables. could someone explain to me: 1) What is the purpose of non-dimensionalizing? 2) Why on the diagram is there an asymptotic line x = 1? Why is L always greater than 1? 3) Why is it a reasonable physical explanation that L > l? Sorry for the silly questions but I've never really had the right set of mind in understanding physical interpreations and math results. Thanks all in advance! And as I am reading from a text and notes, I have just summarised the theory and results. If anything is unclear please let me know and I will try to explain more fully.