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Homework Help: Intro to Physics problem dealing with speed and distance

  1. Feb 27, 2013 #1
    1. The problem statement, all variables and given/known data

    A bug crawls outward from the center of a CD spinning at 200 revolutions per minute. The coefficient of static friction between the bug’s sticky feet and the disc surface is 1.2. How far does the bug get from the center before slipping? What is the speed of the bug just before it starts slipping?

    2. Relevant equations

    Edited my work as I would use this in class. May post on request.

    r = a / w2

    3. The attempt at a solution

    r = 2.6666 cm

    The bug gets 2.66 cm from the center before slipping.

    Q: Does the above seem right? How do I do the second part of the problem where I have to find the speed of the bug before it starts slipping?
    Last edited: Feb 27, 2013
  2. jcsd
  3. Feb 27, 2013 #2


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    How fast is the edge of a circle radius 2.66cm moving if it's rotating at 200rpm?
  4. Feb 27, 2013 #3
    Oh thank you. I got the correct answer with formula, v = ( r ) ( w ). My teacher put the correct answer on the problem for some reason. Thank you.
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