How does rotational interia affect the cornering ability
of a vechile?
Does this relationship change depending on the surface, weight, or speed
of the car?
Rotational inertia is an objects resistance to having its rotational
velocity changed. It is difficult to cause an object of high rotational
inertia to start rotating. Once such an object is rotating, it is difficult
to stop it. To turn a corner, a car must rotate exactly 90 degrees. As the
car begins to turn, it begins to rotate. When the car comes out of the
turn, it stops rotating. A car going through a turn slowly has plenty of
time to start and stop rotating. A car going through a turn quickly must
start and stop rotating in much less time.
Rotational inertia depends on mass and how it is distributed. It is easiest
to control the rotation of a yardstick when rotated around an axis from
end-to-end. When rotating it in the more "traditional" way, around an axis
perpendicular to the stick, starting and stopping quickly become much more
difficult to cause.
Surface has nothing to do with rotational inertia. Surface is a factor in
the torque the car can obtain from the ground. Torque is the rotational
coutnerpart of force. It is how hard something is twisted rather than how
hard something is pushed.
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Update: June 2012