Moving Tire Behavior
I've been told that when the tires of an automobile hit something, let's say a small animal, the animal would be thrown forward, in the direction that the car is heading. However, with the gripping treads on the tires, shouldn't the thing be pulled under the tire, and crushed by the immense weight of the vehicle? Thanks in advance.
It depends on how high up from the ground the point of contact is.
At the top of the tire, the tread is moving forward at twice the speedof the car. At the bottom, the tread is at rest with respect to the road (unless the car is skidding or laying rubber). In between, the forward component of the tread's velocity varies sinusoidally with
height, and there is a downward component that reaches a maximum when the tread is at the height of the axle.
If the animal is tall enough, it's going to get thrown forward; if it's short enough, it'll just get squished. If it's in between, it'll get thrown forward and into the ground, and then get squished.
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Update: June 2012