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Homework Help: Weird globe

  1. Nov 5, 2008 #1
    1. The problem statement, all variables and given/known data
    there is a block sliding down a big globe in Italy.

    2. Relevant equations


    3. The attempt at a solution

    does the globe have its own gravity?

    i'm thinking its A and C.

    Attached Files:

  2. jcsd
  3. Nov 5, 2008 #2


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    No, the globe doesn't have any significant gravity of it's own. Just use the Earth's gravity.
  4. Nov 5, 2008 #3
    and so it is a and c


    once the block leaves the globe

    nothing is pushing the box up (but friction) and nothing is slowing the box down in the horizontal direction (but friction)

    and so the only force is the earth?

  5. Nov 6, 2008 #4


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    Yes, the only force is the Earth's gravity. (So no friction.)
  6. Nov 6, 2008 #5
    ok the next questions asks about about momentum

    im thinking

    centripital acceleration cannot be zero becuz

    is it zero? i dont think so becuz its traveling on a circular path prior to leaving the globe

    normal force must be zero becuz nothing is pushing up

    the net acceleration is down and its velocity is going right and down

    the kinetic energy cannot equal its potential energy becuz you cannot tell if the box is halfway down the globe right?

    so the only choice is normal force right?


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