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-   -   Collision in Western Australia, Australia (http://www.physicsforums.com/showthread.php?t=204117)

Psalter Dec11-07 08:00 PM

Collision in Western Australia, Australia
 
As i am new to these forums i do not have any idea of how many of the members might be from Australia. But here is the scenario, it happened 2 days ago i beleive.

A lady was killed when a drunk driver was heading down the free way... in the wrong direction . She was going (v)= 27.77m/s. he was going (v)= 41.66m/s

Assuming that each of their vehicle collided directly and their was no impact force dissapated or redirected by "riccochet" What would be the impact force be if both their vehicles weighed 1000kg each. (including driver)

If you have any queries or need clarification please don't hesitate. I don't have any idea how to calculate the following or i would

cesiumfrog Dec11-07 08:20 PM

You cannot calculate the "force" without much more detailed information about each vehicle. Are your four significant figures appropriate? Is this a hypothetical (homework) problem, or some morbid fascination with recent tragedy? Why is nationality relevant?

russ_watters Dec11-07 10:26 PM

The force depends on the deformation of both cars and is pretty difficult to calculate. That's what crash tests are for. But you might try assuming the pair decelerates linearly from its 70m/s closing speed to zero in 2 meters (1 for each car), and plug that into the newtonian motion equations.

Psalter Dec11-07 11:09 PM

What about pure amount of force at the moment of impact, not over a lineal time frame ?

As you can tell i am very much a physics noob --.--, didn't pay enough attention at school and then decided to drop out and become a chef.... big mistake .

As for the deceleration, i think that would be a appropriate to say that they decelerated from 70m/s to zero in 2 meters

For this instance should we say that crumple points do not exist on the cars and compensate for that by taking off 25% of the resulting force in the calculations to take into account crumple points, as inaccurate as this may be.

In reply to Csfrogs post,

I only mentioned nationality because chances are if you were in australia you would of heard about the crash.
Its a morbid fascination
The figures specified are appropriate, from my my previous knowledge in physics i know the general velocity unit of measurement is m/s so i took the time to convert the speeds.

Off topic question, Why did you pick Caesium?

Psalter Dec16-07 10:19 PM

Still would like some help with this please guys


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