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Homework Help: Centripetal force/acc problem

  1. Feb 26, 2007 #1
    1. The problem statement, all variables and given/known data
    What angular velocity would cause a centripetal acceleration of 3 g's if the radius were 2.5 m?

    i have a test 2moro on this stuff... yea i need to know =D thx

    2. Relevant equations

    i guess m(v^2)/r or mW^2r

    3. The attempt at a solution

    no idea. srry :confused:
  2. jcsd
  3. Feb 26, 2007 #2
    What is the W? And what do you calculate with mW^2r?
  4. Feb 26, 2007 #3
    W is rotational velocity.. sryy for not making that clear.
    (MASS)(W^2)(radius)=centripetal Force
    W^2R= Centripetal Acceleration
    I just plugged numbers in 29.4= W^2(2.5) and i got 3.4radian/sec for W.
    this looks 2 easy... if someoen could verify please =D
  5. Feb 26, 2007 #4
    Yes, very good, your answer is correct. But you should also write down the units, for example acceleration is in m/s^2 and radius in m. This allows you to check whether your result is correct.

    For example if you calculated W as something with 1/s^2, you know you made a mistake because the unit must be 1/s (or radian/sec).
    Last edited: Feb 26, 2007
  6. Feb 26, 2007 #5
    thanks tons edgardo!
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