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Cable tension question

  1. Mar 11, 2009 #1
    1. The problem statement, all variables and given/known data
    A uniform 20-kilogram beam is supported in a horizontal position by a pin and cable as shown in the figure. Masses M1 and M2 are suspended from the beam. If M1 = 40 kg and M2 = 20 kg, what is the tension in the cable?

    2. Relevant equations

    3. The attempt at a solution
    I don't understand
  2. jcsd
  3. Mar 11, 2009 #2
    I am sorry. I can not see a figure so I have no idea what the situation is like :(
  4. Mar 11, 2009 #3
    james, sum the forces and sum the torques.

    Break the forces into X and y components before you set up your equations

    Then figure out which forces actually have torque and set up a ∑tau equation for that. At that point just solve for T. There is an example in your textbook of a problem similar to this one, use that as a model.
  5. Mar 11, 2009 #4
  6. Mar 11, 2009 #5
    Which example are you talking about?
  7. Mar 11, 2009 #6
    the one with the man standing on the beam. the only difference is that now you have the forces from the two masses as opposed to just one from the man.
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