Dwan Hall
07-09-2006, 12:32 PM
Got this in an e-mail from a frend, Dwan
A Backhoe weighing 8 tons is on top of a flatbed trailer and heading east
on Interstate 70 near Hays, Kansas. Its 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 at 1 foot vertical (depth)
spacings.
Solve: If the shovel arm hits the overpass, how fast would it have to be
going to slice the overpass completely in half? (Assume no effect for headwind and no breaking by the driver...) ...its pure physics: F=MA
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.
(yeah, I know there isn't nearly enough data to solve this, but if we had details and this example was used as an imperial test, we might get close to an answer to the writer's supposition.
..Jim)
A Backhoe weighing 8 tons is on top of a flatbed trailer and heading east
on Interstate 70 near Hays, Kansas. Its 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 at 1 foot vertical (depth)
spacings.
Solve: If the shovel arm hits the overpass, how fast would it have to be
going to slice the overpass completely in half? (Assume no effect for headwind and no breaking by the driver...) ...its pure physics: F=MA
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.
(yeah, I know there isn't nearly enough data to solve this, but if we had details and this example was used as an imperial test, we might get close to an answer to the writer's supposition.
..Jim)