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marsm
Jun17-07, 02:49 PM
1. The problem statement, all variables and given/known data

An idealised car (meaning: a cube with a = 2m) skids sideways toward a curb (height of the curb doesn't matter). At which maximum velocity v must it skid to just about turn over?

Sorry, but the forum didn't generate the TeX for me, so here it is on mathbin.net:

http://www.mathbin.net/11540
1. The problem statement, all variables and given/known data



2. Relevant equations



3. The attempt at a solution

andrevdh
Jun18-07, 04:37 AM
The weight of the car does work while it is rotating about the contact point with the curb. This means that the rotational speed will decrease as it turns over. The work done by it will also change during the rotation. So you have to use

W = \int \tau _{weight} \ d\theta

to calculate the work done and check if the angle is more that fourty five degrees (work-energy theorem).

marsm
Jun18-07, 06:33 AM
Thank you very much, andrevdh, that was a great help!!

My initial calculation was quite wrong, obviously.