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Maximum velocity of buoyant object

  1. Jul 2, 2009 #1
    I have a plastic ball 2.75" in diameter weighing 16 grams submerged at 6 feet depth. I am trying to determine the maximum velocity achieved when I release the ball? Also, if I tether (30) balls together with fishing line at 1/2" spacing how will that affect velocity? I really appreciate any help and input on this. Thank you!
  2. jcsd
  3. Jul 2, 2009 #2

    Andy Resnick

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    Terminal velocity is reached when the buoyant force equals the viscous drag force, which may not occur over the 6 feet. I would start with the full dynamic equation: ma = f_b + f_drag, where f_b is buoyancy and f_d the drag term. Assume Stokes flow for the drag term, and solve for the velocity as a function of depth. You will also have to assume that Stokes flow hold for each sphere in the chain in order to keep this problem easy.
  4. Jul 2, 2009 #3
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