Answer
The center of mass of the system is below the wire. When the system tilts in one direction or the other, the torque from gravity rotates the system back toward its equilibrium position in the middle.
Work Step by Step
The center of mass of the system is below the wire. When the system tilts in one direction or the other, the torque from gravity rotates the system back toward its equilibrium position in the middle.
If the center of mass was above the wire, the torque from gravity would make the system rotate away from the equilibrium position and the object would fall over easily.
