A 7 kg. mass is moved across table at 25 m/sec. What force caused the acceleration?
A push or a pull
The only way an object accelerates is if there is a net force acting on it.
When something is at constant velocity(no acceleration), then there is no net force on the object.
No Net force means when you draw a diagram of all the forces on an object, the magnitude of the forces has to cancel out.
Having Net force means when you draw a diagram of all the forces on an object, one of the forces outweigh the other creating a acceleration.