Which statement best describes a stable equilibrium situation?

• A. The object returns to its original position after a small tilt
• B. The object moves away from its original position after a small tilt
• C. The object remains exactly in the tilted position
• D. The object becomes unstable and falls over quickly

Answer: (A)

Stable equilibrium occurs when a small disturbance produces restoring forces that bring the system back to its original position. That’s why returning to the starting point after a tiny tilt is the best description. It shows a restoring tendency: after you nudge the object, gravity or other forces work to minimize the displacement and bring it back to balance, like a marble rolling back to the bottom of a curved bowl.

If the object moved further away after a small tilt, that would indicate unstable equilibrium—the forces push the system away from the original position. If it stayed tilted with no tendency to return or move further, that would be neutral equilibrium—the forces don’t prefer the original or the tilted position. If it becomes unstable and falls over quickly, that’s another sign of instability, not stability.