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Homework Help: Easy problem giving me trouble

  1. Apr 1, 2008 #1
    A string trimmer is a tool for cutting grass and weeds; it utilizes a length of nylon "string" that rotates about an axis perpendicular to one end of the string. The string rotates at an angular speed of 42 rev/s, and its tip has a tangential speed of 46 m/s. What is the length of the rotating string?
  2. jcsd
  3. Apr 1, 2008 #2
    there is a specific relationship between angular speed and tangential speed. Find the section in your textbook that deals with angular kinematics. Once you find it you will want to hit yourself.

    If it helps, imagine a particle moving in a circle of radius 5 meters, with a tangential speed of 1 m/s. How many revolutions would this particle make in one second?
  4. Apr 1, 2008 #3
    Its just not clicking, I tried this and it didn't work w = 2pi*42/60
    r = 46/w
  5. Apr 1, 2008 #4
    i got it and boy do i feel like an idiot, thank buddy
  6. Apr 1, 2008 #5
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