p=mv ...Its just a simple matter of momentum and velocity - Here's a good link for simple details - I just love how bicycles give us a better understanding of truly important physics...
Lets also not forget I=mrr ...Mass moment of inertia overcoming street surface resistance is why the heavy guy gets to the bottom faster...
http://www.physicsclassroom.com/class/momentum/u4l1a.cfm
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No matter where you're at... There you are... Δf:=f(1/2)-f(-1/2)
Last edited by zandoval; 07-15-12 at 11:48 PM.