- #1
sganesh88
- 286
- 0
I'm driven crazy by this question these days. so here it goes.
Consider a ball sliding on a frictionless surface with some velocity U. If it encounters a surface with friction after some time, then it starts rolling (thats what my intuition says). Meaning that a new rotation component has been added to its motion along with translation. But we know that rotation can be initiated only in the presence of an opposite force that's not inline with friction (non zero lever arm). So how can it roll? It should just keep sliding with decreasing velocity. I know the question could appear silly but please bear. :-)
Consider a ball sliding on a frictionless surface with some velocity U. If it encounters a surface with friction after some time, then it starts rolling (thats what my intuition says). Meaning that a new rotation component has been added to its motion along with translation. But we know that rotation can be initiated only in the presence of an opposite force that's not inline with friction (non zero lever arm). So how can it roll? It should just keep sliding with decreasing velocity. I know the question could appear silly but please bear. :-)