Limiting Friction & Centripetal Force: Explained

[sophiecentaur]

It makes physical sense with the triangular teeth model. The diagonal teeth can slip and at the same time can catch.

If they are slipping and catching at the same time, it would imply that the angles were not uniform. Fair enough but then there would be fewer teeth that were actually catching which would imply less net friction force. We are reaching a familiar stage in this discussion where the questioner seems more determined to make their personal view work than to accept where there are flaws.
Your suggestion that you could have vertical movement of the V teeth without horizontal movement is ignoring the fact that there is a slope. Your model also would have to include a flexible structure if different things happen in different places.
But how can you call one of your forces 'static' if there is movement?
Have you read about this stuff recently? Why not look at the wiki article and then widen your reading with the reading list or just a determined google search? Q and A is not a good way to get a general education about a topic.

 

[pgardn]

If they are slipping and catching at the same time, it would imply that the angles were not uniform. Fair enough but then there would be fewer teeth that were actually catching which would imply less net friction force. We are reaching a familiar stage in this discussion where the questioner seems more determined to make their personal view work than to accept where there are flaws.
Your suggestion that you could have vertical movement of the V teeth without horizontal movement is ignoring the fact that there is a slope. Your model also would have to include a flexible structure if different things happen in different places.
But how can you call one of your forces 'static' if there is movement?
Have you read about this stuff recently? Why not look at the wiki article and then widen your reading with the reading list or just a determined google search? Q and A is not a good way to get a general education about a topic.

The bolded above is patently false. I don't like my model. It's just the only one I had.

 

[pgardn]

If they are slipping and catching at the same time, it would imply that the angles were not uniform. Fair enough but then there would be fewer teeth that were actually catching which would imply less net friction force. We are reaching a familiar stage in this discussion where the questioner seems more determined to make their personal view work than to accept where there are flaws.
Your suggestion that you could have vertical movement of the V teeth without horizontal movement is ignoring the fact that there is a slope. Your model also would have to include a flexible structure if different things happen in different places.
But how can you call one of your forces 'static' if there is movement?
Have you read about this stuff recently? Why not look at the wiki article and then widen your reading with the reading list or just a determined google search? Q and A is not a good way to get a general education about a topic.

Yep I see that now.

 

[pgardn]

It makes physical sense with the triangular teeth model. The diagonal teeth can slip and at the same time can catch.

Again if you model the vertical component of the teeth you get some static friction (which really is a lot like a normal force like in the peg picture I drew. It's possible the peg like tooth could just sheer after exerting a static force. Like if one puts a more massive load on plane of wood till it breaks. Even when something slips this could still exist with the model I already presented using diagonal teeth.The horizontal component of the tooth would allow for the classic slip. I can see different parts of a larger body slipping while others remain static.

Now I may to read more about shearing, compression etc... as I may have ideas about this that are horribly wrong.

But if my simplified model does not fit experiment and observation then it's no good. It's much simpler actually to use your idea of you are static or you are not.

PS

I realize I am not very good at expressing my ideas with English. I'm much better with a face to face sit down while drawing pictures. I tend to think visually before mathematically. So sorry for this.

Admitted I have stepped into deeper water and need to read.

The end. Did not realize I expressed myself obstinately. Sorry.

 

[sophiecentaur]

The end. Did not realize I expressed myself obstinately. Sorry.

Not at all. It's just that we all try to hang onto ideas that we have come to love. You are right to resist a change of view without reasonable cause. A conservative approach is needed or Science would be doing Brownian motion all the time.
Your English is pretty good, aamof. You were getting your ideas across well enough.