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Homework Help: Drag of Copper ball problem

  1. Feb 19, 2006 #1
    It asks to find the vertical force needed to pull the ball in an unknown fluid at a constant velocity. What formulas do I combine and use to find this? They give you the proportionality constant (0.95 kg/s), the constant speed (6cm/s), and the radius of the ball(1.5cm). I already have:

    F (y direction)= F-(mass)(gravity)-Constant(V)

    I found mass from the density and volume. The proportionality constant was given as was the velocity.

    So... F=(mass)*(gravity)-Constant(V)

    Is this right? Because I haven't been able to find the correct answer using it.
    Last edited: Feb 19, 2006
  2. jcsd
  3. Feb 19, 2006 #2


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    Science Advisor
    Homework Helper

    It is unclear what you mean by F(y direction) and F. Define your terms.
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