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maths question

Discussion in 'The Pub' started by waedwe, Jan 9, 2009.

  1. Math Question:

    A Backhoe weighing 8 tons is on top of a flatbed trailer and 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 at 1 foot vertical spacing.

    Solve: When the shovel arm hits the overpass, how fast do you have to be going to slice the bridge in half?? (Assume no effect for headwind and no braking by the driver...)

    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?

    Yes, you can neglect friction.




    I couldn't solve it either......but who cares;

    the pictures are great!

  2. Yes pics are great but the topic header will get this removed unless you change it to not all caps.
  3. It's not really yelling. They are just big letters.
  4. bloody caps lock :deal:
  5. At a guess, I'd say about 40km/h, if the driver doesn't hit the emergency brake. Those things don't move very fast, but they've got enough torque to take anything else with them that gets in the way.