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Nonuniform circular motion merry-go-round

  1. Oct 27, 2007 #1
    1. The problem statement, all variables and given/known data
    A 5.0-m-diameter merry-go-round is initially turning with a 4.0 s period. It slows down and stops in 20 s.
    a. Before slowing, what is the speed of a child on the rim?
    b. How many revoluotions does the merry-go-round make as it stops?
    ( Can i know what is a merry-go-round)

    2. Relevant equations

    3. The attempt at a solution

    I solved a) like that:

    V= 2(Pi)r/T
    V= 2(pi)(2.5)/4
    V= 3.93 m/s

    b) I think this is the correct equation:
    ([tex]\theta[/tex])f = [tex]\theta[/tex]o + [tex]\omega[/tex]o t + a/2r ( t^2)

    but i can't find [tex]\omega[/tex]o or a
  2. jcsd
  3. Oct 27, 2007 #2
    http://www.worldsfinestshows.com/equipment/images/MerryGoRound_1.jpg [Broken]
    Last edited by a moderator: May 3, 2017
  4. Oct 27, 2007 #3
    initially turning with a 4.0 s period ---> T
    α = △ω/△T

    θf = θo + ωo t + α/2( t^2)
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