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Thank god he was wearing his helmet, or it could have been really nasty!

Lord Revan wrote:

Darth Wong wrote:

Lord Revan wrote:just did a quick calculation and 184 miles per hour comes out as 278842 J of KE(if my numbers are correct), so it's no wonder that the guy was for all intents and purposes shreded.

How did you get such a precise estimate of his body weight that you could perform that calculation with so many significant figures?

I guessed, so it not precice (forgot to acount for the bike too).

Sciency procedure caveat: when you GUESS something, the potential error should be reflected in some zeroes at the end of the figure.

In this case we're given:
Speed=184mph=296km/h= ~82.3m/s (three figures to start->three figures all through, even though I could have written 84.30452675 m/s and it would have been mathematically accurate, and having all those didgets hanging around suggests I know EXACTLY what I'm talking about. Which I don't.)
Mass of guy= here's where we're approximating a lot. Nothing good to scale him against, and there isn't enough of him connected together to be able to say how tall he was if there were. He seems pretty average American in typical shape (judging from ...uh, that intact thigh), so we'll call it 80kg.

If we throw those together, we get 270961.4 J, but since we approximated his mass with an error of about 10kg, we've only really got enough data to say what the first one or two digits are. So, say ~270KJ and call it a day. If we were given his mass as 80.000kg (if, say, he was on his way home from a physical with unusually precise scales) we'd still need to call it 271KJ because we only have three figure accuracy WRT speed.

Now you can say you learned something today!

It's sort of an interesting exercise in anatomy. Is that his liver on his chest?

Sriad wrote:Now you can say you learned something today!

I was wondering about something. I think that it is preferable to hold-off any rounding until the end of the operations. In other words, I would have used 84.3045 m/s in my calculations. I got 284289.95 J, and using significant digits, put ~280 KJ as the final solution. We have a slight difference between the two of us, who is more accurate?

Gah, I used 82.3 instead of 84.3! (you can see the typo if you re-read my first post.)

If I'd been doing it right the difference would have been trivial. I would have gotten

a: .5mv^2=.5*80*84.3^2="284259.6"
vs. yours:
b: .5mv^2=.5*80*84.3045^2="284289.9"

For a CORRECTED difference of a petty 30.3 J. Well within the margin that's discarded at the end.

You know what? I read the warnings, and when I Saw the actual pictures, I laughed. The guy is so mangled up to me that he's barely recognizable as a human being, and that, to me, takes a lot of the horror away. If you showed me the picture from ogrish of a shotgun suicide it would unsettle me, because that guy was largely intact except for the head.

I don't think there's anything wrong with me- I get very emotional normally over stuff like this. It just has to be something I can relate to.

Although if the body was in largely the same condition but in a massive pool of blood, it would be far more disturbing to me.

EDIT: I wanted to say that what made me laugh was the fact that my mind conjured up something far worse. I still feel for the guy and his family.

Speaking of blood, where did all of it go? Did most of it get flung out of camera-shot? (I can see some made it on his clothes.) Probably, as I see the skidmark the assorted bodyparts made.

The interesting thing about the 280 kJ figure is that you eat at least 2000 calories worth of chemical potential energy per day in food, and a food calorie is actually a kilocalorie (4186 J), which means that you're consuming chemical energy well into the megajoule range on a daily basis. As a sheer quantity of energy it's actually not that much; it's the manner and speed in which it is applied to your body.

I was driving back from New York today with my father, and we heard a report of an accident on Route 80 West. We were already committed to that route, so we had to suffer through it. Three lanes were closed down, multiple police cruisers were on scene along with an ambulance, supported by night road work lights. As we were merging into the only lane left, we saw another set of emergency lights and sirens come up from behind us. A large black van labelled "Medical Examiner".

When we got a better view of the area, we saw a wrecked sport bike and a white cloth draped over what appeared to be remains of the rider.

Yet another object lesson on the matter.

It seems like the roads just bring out the stupid in people.

I was driving to my father's house a week ago, and drove by a major accident site. Apparently some idiot's car broke down on the I-75 median, and he thought it would be a good idea to run accross the freeway to use a phone................. At midnight, when it was pitch black.

All I saw of him was a red streak on the pavement.

Lord Revan wrote:I guessed, so it not precice (forgot to acount for the bike too).

Why would you assume that the rider has to absorb the kinetic energy of the bike?

Holy shit! Someone I know drives a motorcycle. I could never bring myself to get on one of those things.