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Homework Help: Angular Momentum problem

  1. May 21, 2010 #1
    1. The problem statement, all variables and given/known data

    A 1.9 kg ball attached to a string whose length is 1.8 m moves counterclockwise (as viewed from above) in a horizontal circle (see figure below). The string makes an angle θ = 30° with the vertical.
    (a) Determine both the horizontal and vertical components of the angular momentum of the ball about the point of support P. (Use variables w,t and directions i, j, and k as necessary.)
    horizontal 1
    vertical 2

    (b) Find the magnitude of d/dt.
    3 N*m

    2. Relevant equations

    the equations is what I am trying to solve for.

    3. The attempt at a solution
    I have no idea how to attempt solving this equation :(
  2. jcsd
  3. May 21, 2010 #2

    Andrew Mason

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    Science Advisor
    Homework Helper

    Do a free-body diagram.

    What are the forces acting on the ball. Draw them as vectors. What do all the forces add up to?

    How is that result related to the tangential or angular speed of the ball?

    When you get that far, you may be able to solve the rest.

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