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Homework Help: Blimp Work Problem

  1. Oct 25, 2007 #1
    1. The problem statement, all variables and given/known data

    BlimpWork A blimp of mass 100 kg is pulled at an angle [tex]\phi[/tex] = 27[tex]^{o}[/tex] downwards with respect to the horizontal for d = 10 km on level ground at a constant velocity v = 12 m/s. If the coefficient of drag (K in F = Kv^2) is 0.5 kg • m, how much work in Joules is done by the puller?


    2. Relevant equations
    W=Force * Distance

    3. The attempt at a solution
    This is an example I found and the work they show is:

    Force = Kv^2 = 0.5 kg/meter • (12 meters/second)^2
    Distance = 10 km
    0.5 kg/meter • (12 meters/second)^2 • 10 km= 720000 J

    and obviously the last part doesn't multiply correctly. Is this problem worked incorrectly or am I missing something? I am trying to do a similar problem but, I get the wrong answer when I emulate the above... If the example is wrong how do you work the problem? If not, what am I missing? Also, what about cos [tex]\theta[/tex]?
     
    Last edited: Oct 25, 2007
  2. jcsd
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