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Homework Help: What do I do for these problems ?

  1. Feb 4, 2012 #1
    What do I do for these problems!!?

    1. The problem statement, all variables and given/known data
    1.A merry-go-round makes one complete revo-
    lution in 12.2 s. A 49.4 kg child sits on the
    horizontal floor of the merry-go-round 2.3 m
    from the center.
    Find the child’s acceleration. The accelera-
    tion of gravity is 9.8 m/s2 .
    Answer in units of m/s2

    2.Find the horizontal force of friction that acts
    on the child.
    Answer in units of N

    3.What minimum coefficient of static friction is
    necessary to keep the child from slipping?


    2. Relevant equations

    f=M*A
    a=(Tangential speed)^6/r
    Tangential speed=2pi r/time

    3. The attempt at a solution
    Don't know how to get acceleration
     
    Last edited: Feb 4, 2012
  2. jcsd
  3. Feb 4, 2012 #2

    cepheid

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    Re: What do I do for these problems!!?

    Welcome to PF,

    If the child moves in a CIRCLE at a constant speed, then what MUST be true about the child's acceleration? In other words, what kind of acceleration must he/she be experiencing? How do you go about computing this type of acceleration?
     
  4. Feb 4, 2012 #3
    Re: What do I do for these problems!!?

    Is it the centrapical Acceleration?
     
  5. Feb 4, 2012 #4
    Re: What do I do for these problems!!?

    Help?
     
  6. Feb 4, 2012 #5

    cepheid

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    Re: What do I do for these problems!!?

    Yeah, it's the centripetal acceleration. Now, how do you calculate that (given the parameters of the circular motion)?
     
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