Which factor influences the effect of air resistance on a falling object most significantly?

The factor that most significantly influences the effect of air resistance on a falling object is the shape and area of the object. This is because air resistance, also known as drag force, depends largely on how an object interacts with the air through which it is falling. The shape of the object determines how streamlined it is; a more aerodynamic shape allows it to move through the air with less resistance, whereas a bulkier or irregular shape generates more drag.

In addition, the surface area plays a crucial role in determining how much air the object displaces as it falls. A larger cross-sectional area increases the impact of air resistance because it encounters more air molecules during its descent. This interaction affects the terminal velocity — the constant speed achieved when the force of air resistance equals the gravitational force; a larger area can lead to a lower terminal velocity.

Weight and mass affect the gravitational force acting on the object, but they do not change the nature of the drag force directly. While height can contribute to the time the object has to accelerate, it does not directly influence the drag experienced at any given moment. Speed, just before impact, is a consideration for calculating drag, but it is primarily the shape and area that define how much drag the object experiences during its entire fall