When an object is moving without slipping over another surface, the frictional force acting on it depends on the applied force and the coefficient of friction between the surfaces. In this scenario, the frictional force opposes the motion and acts in the direction opposite to the applied force.
If the object is moving without slipping, it means that the applied force and the frictional force are in equilibrium. The magnitude of the frictional force is equal to the magnitude of the applied force but acts in the opposite direction. This balance between the applied force and the frictional force ensures that the object can move without slipping.
This situation signifies that the frictional force is static friction. Static friction is a type of friction that occurs between two surfaces in contact when there is no relative motion between them. It prevents the object from slipping and enables it to move smoothly without sliding or skidding.
In contrast, if the applied force exceeds the maximum value of static friction, the object will start to slip or slide. In that case, the frictional force transitions from static friction to kinetic friction, which is typically lower in magnitude than static friction.
In summary, when an object is moving without slipping, the frictional force acts in the direction opposite to the applied force and is equal in magnitude to prevent slipping. This signifies the presence of static friction, which enables the object to move smoothly over the surface.