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Homework Help: Spinning Disk - Angular Speed

  1. Mar 16, 2008 #1
    1. The problem statement, all variables and given/known data

    A disk with a radial line painted on it is mounted on an axle perpendicular to it and running through its center. It is initially at rest, with the line at theta 0 = -90°. The disk then undergoes constant angular acceleration. After accelerating for 3.1 s, the reference line has been moved part way around the circle (in a counterclockwise direction) to theta f = 130°.

    Given this information, what is the angular speed of the disk after it has traveled one complete revolution (when it returns to its original position at -90°)?

    2. Relevant equations

    w = lim(change in theda)/(change in time)

    3. The attempt at a solution

    change in theda is 140 degrees

    change in time is 3.1 seconds
  2. jcsd
  3. Mar 16, 2008 #2


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    Homework Helper
    Gold Member

    This is a problem involving a constant angular acceleration and you need to use that information to solve this problem.


    Can you state the kinematic equations for rotational motion?
    Last edited: Mar 16, 2008
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