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Nov 17, 2008

Problem 6/194 - animation





Shown above are animations for two speeds of the auto: the upper frame is a speed slightly below the critical speed, and the lower frame is a speed above the critical speed. 

In both cases, the angular momentum about point O before impact is not due to rotation of the auto but is given by HO = m(rG/O x vG). 

Note that, on impact, the velocity of the center of mass changes instantaneously from directly to the right (at "1") to a direction that is perpendicular to line OG (at "2"). Having the velocity being perpendicular to OG shows that the auto is rotating about point O.

After impact, the angular momentum about O is due to the auto's rotation and is given by HO = IO*omega.

In the upper frame, the speed of G drops to zero slightly before G passes over O. In the lower frame, G has enough speed to make it over the top, and therefore the auto flips on its side.

[Note that I have modeled the curb as a small obstacle so as to not interfere with the tire as the auto tips.]




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