This equation provides the x-component (`x_c` = `z_c`) of the centroid, c, shown in the diagram.

No inputs are required as `x_c` = `z_c` are always zero. 1
The centroid of a three dimensional shape is the arithmetic mean ("average") position of all the points in the shape.
Cylinder (solid) - Radius of Gyration about x-axis
Cylinder (solid) - Radius of Gyration about y-axis