What is the net force on an object in either static or dynamic equilibrium?

In the context of static or dynamic equilibrium, the net force on an object is defined as being zero. This is because equilibrium implies that all the forces acting on an object are balanced.

In static equilibrium, an object is at rest, and the forces acting on it sum to zero, resulting in no acceleration and no movement. Similarly, in dynamic equilibrium, an object is moving at a constant velocity, which also indicates that the forces acting on it cancel each other out completely, leading to a net force of zero. This principle is grounded in Newton's First Law of Motion, which states that an object will remain at rest or in uniform motion unless acted upon by a net external force.

Identifying the net force as zero is crucial for analyzing real-life situations, such as when a book rests on a table or when a car travels at a constant speed on a straight road. The concept of force balance is foundational in physics, as it allows for calculations and predictions regarding the motion of objects.