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Homework Help: Calculate RPM

  1. Nov 10, 2009 #1
    1. I need to find out the kinetic energy of a wheel, mass 15kg, diameter 1.2m, radius of gyration 0.4m travelling at 4ms. To do this I need to find RPM

    2. Kinetic Energy = 0.5 Iw^2, I = mk^2

    3. I = 15 x 0.4^2 = 15 x 0.16 =2.4kgm^2

    KE = 0.5 x 2.4 x w^2

    W = rpm x 2pi/60
    How can I find rpm
  2. jcsd
  3. Nov 10, 2009 #2


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    Hi Kev1n! :smile:

    (have an omega: ω and try using the X2 tag just above the Reply box :wink:)
    Is this a rolling wheel?

    If so, it will have both rotational kinetic energy and ordinary kinetic energy.

    And the speed is 4 m/s, and the diameter is 1.2m, so how far does the wheel move when it goes round one revolution? :smile:
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