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Homework Help: Am i going about this angular acceleration question the right way?

  1. Nov 25, 2008 #1
    1. The problem statement, all variables and given/known data
    A 0.023 g 1.0 inch long second hand on a wristwatch. Find its average angular acceleration?

    2. Relevant equations

    3. The attempt at a solution

    so would i just do 0.023 g divided by 1 minute?
  2. jcsd
  3. Nov 25, 2008 #2


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    Gold Member

    this is an oddly phrased question.

    If the second hand goes around smoothly, it won't have any acceleration just a constant velocity.

    If it's one of those watches that delivers an impulse every second then the hand would move 1/60th of 360 degrees every second. In this case you could use the angular version of the distance equation and solve for a, but you'd have to consider that the second hand goes from 0 to some alpha, then from that alpha back to zero (starting and stopping).

    note: (alpha is angular acceleration)
    Last edited: Nov 25, 2008
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