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Homework Help: Potential enrgy problem

  1. Mar 6, 2008 #1
    A particle has the potential energy shown in the figure. See link below. What is the x-component of the force on the particle at x =5, 15, 25, and 35 cm?

    All answers are in N

    http://img111.imageshack.us/img111/4988/figure2vn4.jpg [Broken]

    i know i should be using -dU/dx
    but i keep getting the wrong answers when x = 5 cm
    I get F = 1N
     
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Mar 6, 2008 #2

    Doc Al

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    Staff: Mentor

    Did you take into account the fact that the x-axis is marked in cm?
     
  4. Mar 6, 2008 #3
    oh, thank you :tongue:
     
  5. Mar 6, 2008 #4
    I'm actually having trouble when x = 25 cm. Is there any advice on how to figure it out?
     
  6. Mar 6, 2008 #5
    -dU/dx means the slope of U-r graph
    slope of U-r graph between 20cm-40cm are the same.
     
  7. Mar 7, 2008 #6

    Doc Al

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    Staff: Mentor

    Use the same method used at x = 5 cm.
     
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