The discussion revolves around calculating the required force to initiate the movement of a sliding door weighing 100 kg that operates on two rollers. Participants explore the forces acting on the system, including friction and potential rolling resistance, and seek clarification on the appropriate formulas to use.
Participants express differing views on the applicability of rolling friction versus rolling resistance, and there is no consensus on the best approach to calculate the friction between the wheel and axle. The discussion remains unresolved regarding the correct methodology for these calculations.
Participants mention inconsistencies in values for rolling friction from various sources, indicating that the values should only be used for approximate calculations. There is also uncertainty about the role of bearings in the system.
This discussion may be useful for individuals interested in mechanical engineering, physics, or anyone involved in designing or analyzing systems that involve rolling motion and friction. It may also benefit those seeking to understand the complexities of calculating forces in practical applications.
tiny-tim said:Hi johnpaul! Welcome to PF!
There's no such thing as "rolling friction", since a pair of rolling surfaces don't move with respect to each other.
There's rolling resistance, which is essentially energy lost due to deformation of the wheel, but I shouldn't think three's much of that with steel.
The main problem will be friction between the wheel and the axle though its centre.