> That sounds pretty awesome. We never got quite *that* far. I think our 
> experiments weren't so precise we had to worry about anything more funky 
> than the total rolling friction of the cars.

Yeh that's fine for linear motion when you don't accelerate or brake too 
hard, but when you are trying to calculate whether the front wheels or rear 
wheels will start to skid first during a sharp corner you have to consider 
how the tyre deforms.  The simple model you can use is to assume the tyre 
surface is like a paint brush - covered in bristles all pointing outwards at 
rest, but they have some stiffness (so they can bend in all directions).

The key point then is that when you start to steer (or brake or accelerate) 
the bristles in contact with the road will bend a certain way, and the ones 
near the edge of the "contact patch" will actually slide across the road 
because they have a very low vertical loading.  As you 
steer/brake/accelerate harder the % of bristles that are sliding across the 
tarmac increase (in a positive feedback loop after a certain point) until 
the whole tyre is skidding across the road.

> We didn't calculate the deformation of the track or anything like that.

For railway cars it's exactly the same situation, just that obviously steel 
is more stiff than rubber, and the track deforms significantly as well.

> Altho I do remember that at one time I knew how to calculate the speed of 
> light given the mass and charge of an electron, and why it worked that 
> way.

I can't even figure out how a black hole manages to bend light when photons 
have no mass :-(

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