SACE Stage 2 Physics Practice Exam 2025 - Free Physics Practice Questions and Study Guide

The drag force is the type of force that acts to oppose motion through a medium, such as air or water. When an object moves through a fluid, it encounters resistance due to the fluid's particles. This resistance is termed drag, which increases with the speed of the object and the density of the fluid. Drag force acts in the opposite direction to the object's motion, thereby hindering its movement and affecting its acceleration.

In addition, the nature of drag force varies depending on factors like the shape of the object, its surface texture, and the flow characteristics of the fluid (laminar or turbulent). An understanding of drag is crucial in fields such as aerodynamics and hydrodynamics, as it directly impacts the efficiency of vehicles, projectiles, and any object moving through a medium.

While gravity, friction, and normal force are all important concepts in physics, they do not specifically denote a force that opposes motion due to a medium in the same way that drag does. Gravity acts downward on an object, while normal force acts perpendicular to a surface to support an object resting on it. Friction opposes the relative motion between two surfaces in contact, but it doesn't apply to motion through a fluid medium in the same context as drag. Therefore