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A pig hanging from a string going in a circle.

  1. Nov 13, 2011 #1
    1. The problem statement, all variables and given/known data
    This is me paraphrasing. It's about uniform circular motion. The question involves a pig on a string dangling below a motor. It rotates in a circle below the horizontal.

    Resolve the tension vector into components. The vertical component of tension is equal to the weight. The horizontal component is equal to the centripetal force. Find centripetal force.

    I'm not really concerned with the numbers I have but just if my logic is correct.

    2. Relevant equations

    Using the angle the string makes with the vertical not the horizontal.

    T* cosθ = mg eq 1

    T*sinθ = centripetal force. eq 2

    3. The attempt at a solution

    Dividing equation 2 by equation one gives you

    T*tanθ = centripetal force/mg

    So m*g*T*tanθ = centripetal force.
    Last edited: Nov 13, 2011
  2. jcsd
  3. Nov 13, 2011 #2
    Did I phrase the question poorly. If so my apologies.

    It's a pig on a string that is hanging from the ceiling. It's spinning around, but not fast enough that it spins completely horizontally.
  4. Nov 14, 2011 #3
    your equations and logic are correct
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