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Homework Help: V(t) and x(t)

  1. Oct 14, 2009 #1
    1. The problem statement, all variables and given/known data

    an object moves to the right with a constant speed v, the ovbject then enters a region where the resistive force is -bv2, find v(t) & x(t)

    2. Relevant equations

    3. The attempt at a solution

    Fx = ma = -bv2

    v = (ma/-b).5

    how do i get t in there
  2. jcsd
  3. Oct 14, 2009 #2


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    Science Advisor
    Homework Helper

    You are treating "a" and "v" as independent now.
    However, the acceleration is related to the velocity as a = dv/dt.
    So your equation is actually:
    m dv/dt = - b v2

    You are going to have to solve a differential equation.
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