OT Posts...Arghhh...

[RU848789]

Lol. As soon as the vehicle is rapidly vaulted upwards, the totally upright tire is visible. I get why you would think this unlikely since an upright tire has a higher center of gravity (harder to get under) and the perspective from a moving vehicle messes with the perception of the actual energy in the spinning tire. Intuitively one might think that a rapidly moving car can pull up on a car carrier that is moving slightly slower; but that is not the case. Once those front tires hit the car carrier and friction is engaged, the spinning energy must be conserved, and the car would be vaulted forward at nearly twice the speed (assuming no heat friction losses). Think of how a pitching machine works, only the tire is much more massive than the wheels used in those machines. The front frame of the Kia only needed to be punched enough so it was raised above the center of gravity of the tire for it to vault over.

Now, for a tire with 70 mph forward momentum to fall to its side and then neatly exit under the vehicle upright goes against Occum's Razor.

Yep, the tire coming out from under vertically does make the tire sliding under the front seem less likely as I said in my original post, but it's still possible and both scenarios are possible and I don't think we can know which occurred without more info. Also, there's no way the car would be vaulted forward at twice its original speed, as the momentum imparted by a tire weighing ~20 pounds simply is not enough to make a car weighing ~200 times that (~4000 pounds) suddenly double its forward speed, since momentum = mass x velocity, so the momentum of the tire will roundly be 200x less than that of the car, since they're both traveling relatively similar speeds. And you can see that the car doesn't really accelerate more than a little, looking at its position relative to the car in front and the truck (which was moving slower than the car to begin with).

 

[RutHut]

Yep, the tire coming out from under vertically does make the tire sliding under the front seem less likely as I said in my original post, but it's still possible and both scenarios are possible and I don't think we can know which occurred without more info. Also, there's no way the car would be vaulted forward at twice its original speed, as the momentum imparted by a tire weighing ~20 pounds simply is not enough to make a car weighing ~200 times that (~4000 pounds) suddenly double its forward speed, since momentum = mass x velocity, so the momentum of the tire will roundly be 200x less than that of the car, since they're both traveling relatively similar speeds. And you can see that the car doesn't really accelerate more than a little, looking at its position relative to the car in front and the truck (which was moving slower than the car to begin with).

I was just trying to illustrate that the spinning tire has a lot of energy which can be directed upward. I don't think it's intuitive to many that a rolling tire has a lot of angular momentum, but if you were to see the tire spinning horizontally at a rate of 15 rotations per second, but not moving, you would sense that it can rip your arm off. There no use discussing anymore, your mind is made up.

 

[RU848789]

I was just trying to illustrate that the spinning tire has a lot of energy which can be directed upward. I don't think it's intuitive to many that a rolling tire has a lot of angular momentum, but if you were to see the tire spinning horizontally at a rate of 15 rotations per second, but not moving, you would sense that it can rip your arm off. There no use discussing anymore, your mind is made up.

My mind isn't made up at all about whether the tire was vertical and the car rode up over it or if the tire slid under and the car rode up on it, but differently (both are plausible to me). With regard to the "twice the speed" comment you made, it was simply wrong, as it would defy the laws of physics given the relative momentum of the two bodies in contact, since the mass of the car is so much more than the tire (but yes, a tire on a car moving 60 mph or 90 ft/sec, at the tread can do some damage).

 

[RU4Real]

Y'all can argue about tires, but all I know is those SUVs can get airborne and land upside down with uncanny consistency.

 

[RutHut]

Y'all can argue about tires, but all I know is those SUVs can get airborne and land upside down with uncanny consistency.

I know, that damned wind propels them 10' in the air!

 

[MADHAT1]

I know, that damned wind propels them 10' in the air!

this subject is tiring and starting to smell with all the hot air being passed .