Equilibrium depends on

Question

Accepted Answer

The correct option is (1):
Wider base of the object is the primary factor that dictates the stability and equilibrium of an object, according to biomechanical principles. Equilibrium, particularly static equilibrium, is achieved when an object is at rest and its center of gravity (COG) is in a low, stable position relative to its base of support (BOS). The principle of stability states that the wider the base of support, the more stable the object becomes because the line of gravity (an imaginary vertical line passing through the COG) has a greater area to move before it falls outside the base. When the line of gravity extends beyond the base of support, the object loses its balance and begins to topple. Thus, widening the base, such as by standing with feet apart, fundamentally increases an individual's or object's resistance to angular momentum and external forces, thereby promoting better equilibrium.

The incorrect option is (2):
More height of the object is actually a factor that *decreases* the equilibrium or stability of an object. Stability is inversely proportional to the height of the center of gravity above the base of support. Raising the height of an object also raises its center of gravity. When the center of gravity is high, a smaller angular displacement is required for the line of gravity to fall outside the base of support. This makes the object top-heavy and easier to destabilize. For maximum stability, engineers and athletes alike seek to keep the center of gravity as low as possible.

The incorrect option is (3):
Light weight of the object does not inherently promote better equilibrium; in fact, a heavier object generally has greater inertia, which helps resist changes in motion, including being knocked off balance by an external force. While weight is a component of stability (a heavier object is harder to move), the most crucial structural determinant of *equilibrium* is the relationship between the center of gravity and the base of support. A very light object can still possess great equilibrium if it has an extremely wide base and low center of gravity. For example, a light, flat disc is far more stable than a heavy, tall rod. Therefore, weight is secondary to the base area and COG height in determining an object's static equilibrium.

The incorrect option is (4):
Narrow base and light weight of the object represents the combination of features that results in the *least* amount of equilibrium and maximum instability. A narrow base provides a minimal area for the line of gravity to fall within, making it very easy to tip the object over with even a slight push or angular displacement. Simultaneously, a light weight means the object offers minimal inertial resistance to any external force applied to it. Consequently, an object with a narrow base and light weight is structurally predisposed to falling and has the poorest static and dynamic stability.