Final answer:
The neutral zone is significant for the placement of objects in neutral equilibrium, where their center of gravity remains unchanged upon displacement.
Step-by-step explanation:
The neutral zone should be established for the placement of objects that exhibit neutral equilibrium. In physics, when an object is in neutral equilibrium, its center of gravity (cg) does not change position when it is displaced. An example of this can be seen in a sphere resting on a flat surface as shown in Figure 9.15(a); irrespective of where the sphere is on the surface, its center of gravity remains vertically above the point of support. Similarly, a pencil with a circular cross-section is in neutral equilibrium for displacements perpendicular to its length, as indicated in Figure 9.15(b). When such objects are displaced, they will stay put instead of returning to their original position or falling over, which characterizes neutral equilibrium.