The discussion centers on the conservation of energy in a rolling wheel, specifically addressing the role of static friction. It is established that static friction does not perform work, thus energy is conserved as long as there is no slipping between the surfaces. The conversation highlights the distinction between static friction and rolling resistance, the latter being a factor due to deformation of the wheel and road, which is often overlooked in basic physics education.
PREREQUISITESStudents studying physics, educators teaching mechanics, and anyone interested in the principles of energy conservation in motion.
The force is 'trying' to move the surfaces in relation to each other. Does it succeed?paalfis said:Linear integral of scalar product between force and the direction of motion. But does THIS force does any work? Because after all, it is static, but its point of action is changing with time, that is my confusion.
Correct.paalfis said:Energy won't be conserved if there is any slipping between the surfaces, correct?
There is some truth in that. In the case of a rolling wheel, there are losses associated with the deformation of the road and wheel as the load shifts. But this is referred to as rolling resistance, not friction. It is generally ignored in 'school', in the same way that air drag is ignored in most ballistics questions.paalfis said:I think static force as 'pressure' applied by each body to the other body, somehow using energy to change the molecular state of the other body's structure