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Homework Help: Lever system - brake (counting of forces)

  1. Nov 6, 2012 #1
    I tried to solve this question:
    So F1D1=F2D2. Thus:
    60N/ 0,06m x 0,2 m= f/0,02m x 0,04m
    =100 Newton applied to the piston, but this doesn't fit to the answers offered.
    What did I wrong?:(
  2. jcsd
  3. Nov 6, 2012 #2
    Why are you dividing the 60 N force by 6 cm?
  4. Nov 6, 2012 #3
    Because it applies some force on the area, isnt it?

    It's so easy, that I just need to divide 60N by 0,2M?
  5. Nov 6, 2012 #4
    I think you are mixing the lever rule with the hydraulic press (Pascal principle).
    The question is about forces. You don't need pressures. And dividing by 6 cm will not give pressure anyway (it's piston's diameter not its area).
    Are there more questions related to the same diagram?
  6. Nov 6, 2012 #5
    No, only this one.
    Have you managed to solve it?
  7. Nov 6, 2012 #6
    Use the equation for the lever or just equilibrium of torques around the pivot.
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