Calculate speed of vehicle vs distance of pedestrian traveled

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To calculate the speed of a vehicle based on the distance a pedestrian was thrown, several factors must be considered, including the weights of both the vehicle and pedestrian, the distance traveled by the pedestrian, and the height difference at the impact site. The discussion highlights the need for professional expertise in crash-scene investigations, as various forces can influence the results. Typical methods for estimating vehicle speed involve analyzing pedestrian throw distances and applying relevant physics formulas. The original poster acknowledges the limitations of the forum for such technical inquiries but seeks guidance on further investigation. Ultimately, accurate calculations require comprehensive data and professional analysis to ensure reliability.
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I would like to calculate the above. Here are the factors. This has real life repercussions, and if further variables are required I will provide them if possible.

Vehicle weight (x=4986LB) includes 120LB driver, plus 50lb child and 60lb child
Pedestrian weight (p=320LB)
speed of vehicle (v=?)
distance p traveled (d=90ft)
difference in height (h=15ft) lower than impact because impact was on a hill and p landed in ditch
time (t=?)
acceleration (a=?)
gravity (g=9.81m/s squared)

please include formula/s used and how they applied. Thanks in advance.
 
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It sounds like you are trying to make a case for something in real life.
This is not a good forum to do this in.

Since this is important, you should employ a professional crash-scene or scene-of-accident investigator.

Aside:
You appear to want to know how fast a vehicle was going from the distance a pedestrian was thrown.
Typical approaches include:
http://jneades.com/downloads/Pedestrian%20throw.pdf
http://autoaccidentreconstructionguide.com/pedestrian-collision-investigators-guide-in-investigating-pedestrian-collisions/
... care has to be taken with these as there may be forces acting other than the impact and gravity.
 
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You are correct, and I agree this may not be the best place, and I apologize for that. Perhaps there is a "good" place somewhere, I just haven't found it yet.

The investigation is over as far as they are concerned, and they did not complete certain areas of investigation, like indicated above. This is why I am here.

You have given me a few leads, I will do my best with that. Thanks.
 
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