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Old 04-10-2018, 02:50 PM   #20 (permalink)
Ecky
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Quote:
Originally Posted by RedDevil View Post
Sorry, but tire size has no effect on rotational inertia.
A taller tire has quadratically (not exponentially) more inertia for its bigger size, but the speed relation is also quadratical - and it rotates less fast than a smaller tire would for the same speed of the car, so these effects precisely cancel each other out.
Correct me if I'm wrong, but circumference is Pi*diameter(or 2r), whereas inertia is mass * radius (of rotational average center of gravity, or whatever the proper term for that is) squared. So, a wheel with twice the circumference would have twice the radius, and be spinning half as fast. It would have four times the rotational inertia at a given speed, but since it's spinning half as fast, its inertia is only doubled.

What am I missing?
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