28.1. Catenary

In a catenary the tension in the line changes due to the weight of the line. Given that there is only its own weight, the Horizontal component of the tension does not change and is the same at each segment. The change in Vertical force is caused by the increase in weight of the segment and this changes the angle of the line. The catenary equation describes a natural curvature of lines which is common in nature and in this example is immediately recognizable.

A fine balance arises from the restoring force and the line’s shape, both suspended and in contact with the seabed: