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David Morin, in "Introduction to Classical Mechanics" says that friction does not exert a force on a car because the ground is fixed but that KE of the car is changing to internal kinetic energy in the form of heat and he mentions Hybrid cars , which convert kinetic energy into chemical potential energy in a battery.

But pages earlier, he mentions the famous example of friction on a sliding book: friction does no work on the cars but does work on the book. although the ground is not moving in both cases.

He says that ".. force acts over zero distance", albeit friction is so intuitively simple it contains so many subtleties that I find it hard to master it.

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The contact point between the wheel and the car is stationary - there is no "rubbing" there (well there is because the contact point is really a patch but let's keep it simple). To do work you need "force times distance" - and without relative motion there is no "distance".

When you apply the brakes in a car you have sliding of the pads relative to the rotors - and work converted to heat (or, in a hybrid, when you use regenerative braking, to electrical / chemical energy)

Floris
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