alt Hacker NewsFor some reason I cannot reply to your comment wizzwizz4.
We are talking about dynamic friction in it's simplest form. You can treat it as simple math problem too. Let's consider two extreme cases:
A: Side slip is 1m/s and wheel spin zero or very small.
B: Side slip is 1m/s and wheel spin extremely big, let's say 1000m/s.
I think we can agree that friction is always opposite to surface speed. If wheel spin is on x axis and side slip on y:
On A case friction is (0, 1).normalized() * friction-coefficiency => (0, friction-coefficiency)
On B case friction is (1000, 1).normalized() * friction-coefficiency => [approximately] (friction-coefficiency, 0)
On classroom teacher says that slip does not matter. What teacher actually means that slip does not effect into -magnitude- of friction but this is left behind because problem is presented in context of 1D. Tho in 1D slip still matters little bit because there is difference is slip 1m/s or -1m/s.
> I think we can agree that friction is always opposite to surface speed.
This isn't intuitively obvious to me. One explanation says "must be true", another explanation says "might be false". I'd want to run an experiment with a toy car on a polished surface. Unfortunately, I'm quite a way from the nearest place I could set up such an experiment.