forwarded by email today:
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Problem: A backhoe weighing 8 tons is on top of a flatbed trailer heading east on Interstate 70 near Hays, Kansas ? The extended shovel arm is made of hardened refined steel and the approaching overpass is made of commercial-grade concrete, reinforced with 1 1/2 inch steel rebar spaced at ?6 inch intervals in a criss-cross pattern layered with 1 foot vertical spacing.

Solve: ? When the shovel arm hits the overpass, how fast does the trailer with the backhoe have to be going to slice the bridge in half?? (Assume no headwind and no braking by the driver who is oblivious of the situation . . . )

Extra Credit: Solve for the time and distance required for the entire rig to come to a complete stop after hitting the overpass at the speed calculated above .
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Answer: Scroll down..........
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Answer -? ? It doesn't really matter... ? The point is that the trucking company just bought themselves a bridge...