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Homework Help: Free response

  1. May 6, 2007 #1
    A pendulum consisting of a small heavy ball of mass m at the end of a string at length L is released from a horizontal position. When the ball is at point P, the string forms an angle of 30 degrees with the horizontal.
    a.) what are the forces acting on the ball and their directions
    b.)Determine the speed of the ball at P.
    c.)Determine the tension in the string at P.
    d.)Determine the tangential acceleration of the ball at P

    I think the cetripetal force acts diagonally to the right and the force of gravity points downward

    I am confused on what to do for b c and d
  2. jcsd
  3. May 6, 2007 #2
    i would really appreciate some help
  4. May 6, 2007 #3
  5. May 6, 2007 #4


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    Homework Helper

    You haven't shown much work here. You should try to at least show some equations or something!

    For (b) you could use conservation of energy. If you take the potential energy to be zero at P, what is the potential energy when the ball is raised to the horizontal position? What does that tell you about the kinetic energy of the ball when it is at P after being released?
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