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Homework Help: Yo Yo Problem

  1. Oct 16, 2006 #1
    A yo-yo of mass .3 Kg with a radius .03 m spins on an axel of radius .02 meters. It is dropped a distance .8 m, what is its final velocity?

    I started:

    mg -T=ma
    mr(0)t = I(alpha)-->(alpha)= a/r

    So:

    mg - (Ia)/mr(0)^2 = ma

    a = mg/ (m + I/(mr(0)^2)

    I = 1/2 mR(1)^2

    I checked over this numerous times and was unable to find my error, but I keep getting 2.06 for acceleration. The acceleration that would lead to the correct answer is 4.6 (m/s^2).
     
  2. jcsd
  3. Oct 16, 2006 #2

    OlderDan

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    Science Advisor
    Homework Helper

    Everything you have said looks correct. I cannot see an error that would lead to the answer you got, but you must have made an algebra mistake. I got a = 4.6m/s^2
     
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