What type of friction force acts on rolling objects?

The friction force that acts on rolling objects is known as rolling friction. This type of friction occurs when an object rolls over a surface, rather than sliding. Rolling friction is generally lower than static or sliding friction, which makes it easier for objects to roll. It is primarily due to the deformation of the rolling object and the surface it rolls on.

For example, when a wheel rolls on the ground, there is a slight deformation at the contact point, which allows the wheel to maintain movement without excessive resistance. This characteristic of rolling friction is what makes vehicles more efficient compared to ones that slide or skid, such as those that rely heavily on sliding friction. This efficiency is significant in applications where energy conservation is important, as rolling motion allows for smoother and more controlled movement.