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Homework Help: Homework questions - Newton's Laws

  1. Mar 15, 2012 #1
    (1)A "swing" ride at a carnival consists of chairs that are swung in a circle by 10.0 m cables attached to a vertical rotating pole at an angle of 60 degrees with respect to the pole. Suppose the total mass of a chair and its occupant is 200 kg. (a) Determine the tension in the cable attached to the chair. (b) Find the speed of the chair.

    (2)At an amusement park there is a ride in which cylindrically shaped chambers spin around a central axis. People sit in seats facing the axis, their backs against the outer wall. At one instant the outer wall moves at a speed of 3.62 m/s, and an 88.9-kg person feels a 507-N force pressing against his back. What is the radius of a chamber?


    Can anybody help me with how to start negotiating this problem? I'm not sure how to begin. I was taught to draw free body diagrams first but that doesn't seem to get me anywhere.
  2. jcsd
  3. Mar 15, 2012 #2


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    Homework Helper

    welcome to physicsforums, tbtheqt!

    Free body diagrams are the right method. Start with the first question. Write down the free body force diagram for the chair. and then the question tells you that the chair swings in a (horizontal) circle, so what does this tell you about the sum of the horizontal forces? And also, you know the chair does not accelerate vertically, so this tells you something about the sum of the vertical forces
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