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Modiefied Atwood Machine Problemneed help.

  1. Apr 28, 2009 #1
    1. A wheel is rotating about an axis perpendicular to the plane of the wheel and passing through the center of the wheel. The angular speed of the wheel is increasing at a constant rate. Point A is on the rim of the wheel and point B is midway between the rim and the center of the wheel. For each of the following quantities, it is the magnitude larger at A or at B, or is it the same at both points: a) angular speed, b) tangential speed, c) angular acceleration, d) tangential acceleration, and e) centripetal acceleration. Justify your answers.

    2. Relevant equations

    (tangential speed) v= rw
    (angular speed) w=v/r or 2π/t
    (tangential acceleration) = r * (change in w/ change in t)
    (angular accel.) =change in w/ change in t

    3. The attempt at a solution

    I know that the further a point is from the center, the faster its velocity.
    the closer a point is to the center, the slower its velocity.
    Therefore, the magnitude will always be greater at point A?????
    I think Point a = r(radius) and point B= 1/2r.....
    I dont know how to approach the problem...
  2. jcsd
  3. Apr 28, 2009 #2


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    Homework Helper

    When the wheel is moving every particle on the wheel describes the same angle at the center. Then what happen to the angular speed?
    The tangential velocity has the same magnitude but it changes the direction. Then what happens to the tangential speed?
    Proceed in the same manner for other quantities.
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