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Homework Help: Velocity Of The Ice As It Hits The Ground?

  1. Jan 21, 2008 #1
    The John Hancock Center In Chicago Is The Tallest Building In The United States In Which There Are Residential Apartments. The Hancock Center Is 343m Tall. Suppose A Resident Accidentally Causes A Chunk Of Ice To Fall From The Roof. What Would Be The Velocity Of The Ice As It Hits The Ground? Neglect The Air Resistance
     
    Last edited by a moderator: May 9, 2015
  2. jcsd
  3. Jan 21, 2008 #2

    Integral

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    Seem pretty stright forward, what is your question?
     
  4. Jan 21, 2008 #3

    rock.freak667

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    1) What did you try?
    2) See above
    3) Think energy
     
  5. Jan 21, 2008 #4
    Ok I Tried


    D=343m
    Vi=0
    A= -9.8 M/s


    Looking For Vf=


    Vf^2=0^2+2 X -9.8 X 343

    And Then I Solved It From There
     
  6. Jan 21, 2008 #5
    Looks like.
     
  7. Jan 22, 2008 #6
    s=343 u=0 a=9.8


    v^2=u^2+2as

    v^2=2as

    v^2=2*343*9.8
    v^2=6722.8
    v=82 m/s

    the mistake you've made is putting gravity as -9.8 when it is actually 9.8 as the object is accelerating towards the earth.
     
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