Final answer:
The net force acting on an object at rest is zero newtons (N), as per Newton's First Law of Motion, which describes a state of equilibrium where balanced forces result in no acceleration.
Step-by-step explanation:
According to Newton's First Law of Motion, an object at rest is in a state of equilibrium where the net force acting upon it is zero. This is because the forces are balanced, meaning there's no acceleration happening to the object. In the specific case of an object being at rest, the sum of all forces equals 0 N (newtons).
When a car is parked, for example, the weight of the car is balanced by the normal reaction force from the ground, resulting in a net force of zero. This keeps the car stationary unless an additional force is applied to change its state of motion. As per Newton's first law, as long as the net external force is zero, the velocity of the car will be zero, indicating the car is at rest.