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Homework Help: Power - Ferris Wheel with friction

  1. Apr 12, 2010 #1
    1. The problem statement, all variables and given/known data
    A motor keep a Ferris wheel (with moment of inertia 8.95X10^7 kg X m^2)rotating at 6.3 rev/hr. When the motor is turned off, the wheel slow down (because of friction) to 3.5 rev/hr in 25 s. What was the power of the motor that kept the wheel rotating at 6.3 rev/hr despite friction? Answer in units of W.

    2. Relevant equations
    P = [tex]\Delta[/tex]W/[tex]\Delta[/tex]t

    3. The attempt at a solution
    Well, if I interpret it correctly, I guess I have to convert 3.5 rev/hr to rad/s. Correct? And find W by FD? Sorry, I am too sure what to do. Thanks for your help.
  2. jcsd
  3. Apr 12, 2010 #2
    SORRY, someone else posted it already
  4. Apr 12, 2010 #3
    You wouldnt by chance be in Professor Woods' class?
  5. Apr 23, 2010 #4
    I am in his class. I can tell you are since you have "Bull" in your username. ;)
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