An artist designs a kinetic wind sculpture consisting of a uniform horizontal carbon-fibre rod of weight WWW, supported by a frictionless pin-joint at its exact center.
Figure 1 shows the balanced arrangement of the sculpture in calm air.
Suspended from the left side of the rod is an ornamental brass leaf.
Suspended from the right side of the rod is a rough volcanic rock counterweight.
The entire system is in static equilibrium.
State the relationship between the clockwise moment of the force exerted by the volcanic rock and the anticlockwise moment of the force exerted by the brass leaf about the central pin-joint.