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Homework Help: Spinning wheel

  1. Nov 21, 2005 #1
    In “Rumpelstiltskin,” the miller’s daughter is spinning straw into gold on a spinning wheel that turns at a speed of 7.5 m/s, making one revolution every 0.50 s. How long is a strand of gold that makes one complete turn around the wheel?

    I know I am supposed to be telling what I know, but frankly I have no idea how to do this. I do no know the equation. I also do not understand how the wheel spins at one speed; isn't it supposed to spin at different speeds in different parts??

  2. jcsd
  3. Nov 21, 2005 #2


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    You have to assume that the 7.5m/s refers to the speed of the perimeter of the wheel. Knowing that the perimeter of the wheel goes at 7.5m/s and that it makes one full revolution in 0.5 seconds, does that help? Applying only simple geometry now ^^
  4. Nov 21, 2005 #3
    have you learned dimensional analysis?

    multiplying 7.5 m by .5 s gives you the number of meters in one revolution, which is what you're looking for.
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