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Homework Help: Static Equilibrium-Balancing Forces and Torque

  1. Oct 20, 2011 #1
    1. The problem statement, all variables and given/known data
    Two children of masses 45 kg and 30 kg are playing on a teeter-totter of length 4.0m and mass 30.0kg, pivoted at its centre. The heavier child sits 1.75 m from the centre of the teeter-totter that is 0.50 m from the ground. a) What torque does the teeter-totter apply to each of its sides? With this knowledge, how could you simplify any further calculations.

    2. Relevant equations

    T=r x Fsin(theta)

    3. The attempt at a solution
    The example says:
    T=rF sin (theta)
    T=(1.0 m)(30.0 kg)(9.8 N/kg)
    t-t  147 N·m

    I don't understand where the one metre is coming from.
    Can anyone help me?
  2. jcsd
  3. Oct 21, 2011 #2
    The question is too vague to answer. It doesn't specify the coordinates of the other child.
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