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Homework Help: GPE and a ball

  1. Nov 5, 2005 #1
    Can anyone help me with this problem?

    A 1.70 kg ball is attached to a ceiling by a 1.15 m long string. The height of the room is 3.00 m. What is the gravitational potential energy of the ball relative to the ceiling and floor?

    I'm having trouble finding the displacement. I know that its going to be mass x gravity x displacement... so thats 1.70 x 9.8 x displacement... i thought it was 3-1.15 but that didnt work
     
  2. jcsd
  3. Nov 5, 2005 #2
    It has a GPE relative to the ceiling (its displacement is the distance to the ceiling) and a GPE relative to the floor (its displacement is the distance to the floor).
     
  4. Nov 5, 2005 #3

    lightgrav

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    Homework Helper

    " Potential Energy" is named that because we can imagine scenarios in which a Force would "potentially" do Work, if the process occurred.
    I can imagine that somebody hits the yo-yo sideways so that it swings up to the ceiling.
    But then, the string might break ... .
     
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