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Homework Help: Velocity and resistance problem. diff Eq type

  1. Oct 4, 2005 #1
    A body moving with velocity V enounters a resistance in the form of dV/dT=-k*V^(3/2). Show that

    V(t)=(4v.)/(k*t*sqrt(v.)+2)^2
    v. is the same as v(subscript 0)


    When i solve the differential equation i keep getting V(t)=4/(k*t-v')^2

    I have no idea how to get from dv/dt to the given v(t)
     
  2. jcsd
  3. Oct 4, 2005 #2
    try an intergal
     
  4. Oct 5, 2005 #3
    oh wow I would have never though to that!

    since i figured it out on my own, you verify from v(t) that v(0)=v. solve the diff eq then set t=0 and set it = to v. solve for constant C sub back into equation and get the anwser.
     
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