Final answer:
When a net force is negative, it means that the force is acting in the opposite direction of the chosen positive direction. This indicates that the forces are causing the object to slow down or move in the opposite direction.
Step-by-step explanation:
In physics, when a net force is negative, it means that the force is acting in the opposite direction of the chosen positive direction. A negative net force indicates that the forces acting on an object are causing it to slow down or move in the opposite direction. For example, if a net force of -200 N is applied to an object, it means that the forces acting on the object are causing it to move in the opposite direction with a magnitude of 200 N. Understanding the sign convention for forces is important in physics to accurately analyze and interpret the motion of objects.