What phenomenon occurs when objects fall through fluids such as gas or liquid?

When objects fall through fluids, such as air (gas) or water (liquid), they experience a phenomenon known as terminal velocity. As an object falls, it accelerates due to the force of gravity, but as its speed increases, the resistance from the fluid (drag force) also increases.

At a certain speed, the drag force equals the weight of the object, and at this point, the acceleration stops. The object continues to fall at a constant speed, known as the terminal velocity. This concept illustrates the balance of forces acting on the object – when the forces are equal, there is no further acceleration. Various factors, including the object's shape, size, and mass, influence the terminal velocity, and it is a critical consideration in both physics and engineering.

In contrast, the other statements do not accurately describe the behavior of falling objects in fluids. Objects do not accelerate indefinitely since the drag force counteracts gravity; they do reach a constant speed (terminal velocity), and they do not only slow down continuously without eventually reaching this steady state.