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Old 12-21-2009, 01:29 AM   #74 (permalink)
winkosmosis
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Quote:
Originally Posted by Christ View Post
That is quite a possibility, but I can't infer something from it that's not in words already, as I would only be guessing.



That's a gimme, basic physics. Force is equal to Pressure*Area, so if you increase either of those variables, force increases, and with more force, you get a higher friction coefficient.

This is why it's harder to slide your hand against any surface the harder you push down, to borrow an analogy earlier used in this thread.
No, in basic physics the coefficient stays the same which is what you're talking about with the hand example. Theoretically you press down 2x, and friction increases 2x because the coefficient doesn't change. That's why people are arguing that you can reduce contact patch and end up with the same traction.

With the motorcycle tire example, you press down 2x, and the traction force increases 1.8x. Reduce by your contact patch by 1/2x, and your traction force is 10% less.

He says it's not linear, so it's probably different from 10% for the average car.
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