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Homework Help: Finding ω and T of a Pendulum With No Numbers

  1. Dec 9, 2012 #1
    1. The problem statement, all variables and given/known data

    All this problem says is to find ω and T of a pendulum with a length L and mass m.
    There's a picture of a pendulum labeling the arc length, length, mass, and angle θ with just symbols.

    2. Relevant equations



    3. The attempt at a solution

    I tried solving algebraically to find T using ƩFy=T-mg=0. I don't know if I made any real progress; I'm not very good at these kinds of problems. I need numbers to really understand these kinds of problems. I'm almost concerned that the correct answer might be a number.
     
  2. jcsd
  3. Dec 9, 2012 #2

    SteamKing

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    Do you know what the variable symbols mean? What is T for instance?
     
  4. Dec 9, 2012 #3
    T is tension. ω is angular velocity. It uses θ for the angle, s for arc length, L for length of the rope/string of the pendulum, and m for mass.
     
  5. Dec 9, 2012 #4
    There's a possibility I'm over-thinking it. My instructor likes to go all-out with some questions, but this might just be him checking out understanding. I'm not sure.
     
  6. Dec 9, 2012 #5

    haruspex

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    Drawing the free body diagram for the pendulum bob when the pendulum is at angle θ to the vertical, what expression do you get for the tension?
     
  7. Dec 9, 2012 #6

    SteamKing

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    Are you sure T stands for tension? Are pendulums important in physics because they measure tension?
     
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