Microwave Oven on 6/10/2007 at 00:35
You know, this whole thing started because I knew CSI is a joke. To me it's like a comedy, but with murder. So when I busted out laughing at the absolutely wrong statement that the tire fragment was moving 120 relative to the guy's head, my friend (who takes CSI *very* seriously) asked me what was so funny. I explained how the relative motion of all the parts of the scenario could not possibly add up to such a high number. My friend refused to believe me and tried to convince me that I was completely wrong and that the writers had gotten it right. Which then led to a loud half hour debate. Oy.
Now, my friend isn't a dummy (CSI fanhood aside) and has a doctorate (not in physics though), so when they are that adamant about something, I usually take their word for it. However, on the subject of physics, I'm on steady ground, and I didn't back down. Which led to shouting.
I asked here because I really just needed a check to see if I wasn't missing something completely obvious about physics, and I didn't waste 30 minutes making an ass of myself.
37637598 on 6/10/2007 at 04:22
It also depends on whether or not the tire shredded apart right away, or if it just tore, deflated, and fell off. I'll be right back with my view...
Chade on 6/10/2007 at 06:35
Perhaps the go-kart rider was head-banging at 60 mph?
rachel on 6/10/2007 at 13:02
Quote Posted by 37637598
It also depends on whether or not the tire shredded apart right away, or if it just tore, deflated, and fell off. I'll be right back with my view...
The tire did not shred, it rolled on a tire debris that was there on the road. It's that debris that was projected backwards.
Mortal Monkey on 6/10/2007 at 13:06
This thread reminded me of a similar question:
What gives you the highest chance of survival, a head-on collision with a big tree at 40 MPH, or a 40 MPH head-on collision with a completely identical car going the same speed in the opposite direction?
LesserFollies on 6/10/2007 at 15:14
In answer to raph's question, the "recreation" had him throwing up his hand (he only lost one) to ward off the blow, thus the loss of his hand. Speaking of dodgy science, there was an episode where they solved a murder by "playing" a textured hand-thrown pot... the idea being that a conversation was recorded in the grooves while it was on the wheel, like with a phonograph record. That can't be right. Can it?
edit: page 2 at 120 mph
Muzman on 6/10/2007 at 15:24
Quote Posted by Microwave Oven
Now, my friend isn't a dummy (CSI fanhood aside) and has a doctorate (not in physics though), so when they are that adamant about something, I usually take their word for it. However, on the subject of physics, I'm on steady ground, and I didn't back down. Which led to shouting.
James "The Amazing" Randi once surmised that the Phd parchment, for any field, is dipped in a peculiar psycho-active chemical that, when grasped passes through the skin into the bloodstream, racing into the brain. There it damages or destroys the part of the brain responsible for the notions "I don't know" and "I was wrong".
Ever noticed how the clerks handing out the parchments are wearing gloves. :weird:
Jeshibu on 6/10/2007 at 15:45
Quote Posted by LesserFollies
In answer to raph's question, the "recreation" had him throwing up his hand (he only lost one) to ward off the blow, thus the loss of his hand. Speaking of dodgy science, there was an episode where they solved a murder by "playing" a textured hand-thrown pot... the idea being that a conversation was recorded in the grooves while it was on the wheel, like with a phonograph record. That can't be right. Can it?
Mythbusters tried and failed to do that. There was some sound imprinted by shouting at it, but they couldn't "play" it to sound like a voice of any kind.
heywood on 6/10/2007 at 17:01
Quote Posted by Mortal Monkey
This thread reminded me of a similar question:
What gives you the highest chance of survival, a head-on collision with a big tree at 40 MPH, or a 40 MPH head-on collision with a completely identical car going the same speed in the opposite direction?
The head-on collision. That one's easy.
Pyrian on 7/10/2007 at 05:20
Quote Posted by raph
The tire did not shred, it rolled on a tire debris that was there on the road. It's that debris that was projected backwards.
Ah. Well, if the tire wasn't exploding, than it's harder to find a likely cause of high-velocity backwards motion. But it's still not
impossible. Grab a small object and squeeze it between two fingers until it shoots out of your hand. The common in-thread assertion that the movement speed of the cars and any given part of the tire forms some sort of upper limit to the velocities that can result from their interaction is flat-out false. The weight of the truck compared to the weight of the tire fragment can provide for a potentially very high velocity.
You'd need oil on the road and on part of the fragment. Specifically, you'd need oil on the "forward" part of the fragment such that the rubber-to-rubber would grip as the tire started over it, then suddenly give when the tire was on the other side. At that point, you'd have tremendous pressure on the tire fragment and very little friction keeping it in place - it could then shoot out backwards.
