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Need help with these questions A.S.A.P

  1. Dec 9, 2004 #1
    I really need some help solving these two questions. Any help is appreciated!

    1) A tapered(non-uniform) power pole has a mass of 350 kg and a length of 12.2m. A cable attached to the smaller end has a tension of 1110N just as the end is about to ris from the ground. Where would the cable have to be attached in order for the pole to rise horizontally?

    2)If a power-lifter was to lift 263.5kg mass over his head using a 1.3m long barwith weights on the end, (assuming the centre of gravity for the bar and weights is at the center) what is the force each hand exerts if they are both 0.27m from each end?

    I'm not asking for the answers to be given to me, I just need some help setting up the questions, and also i cant figure out where I should put the pivot points. Thanks again for any help!
  2. jcsd
  3. Dec 9, 2004 #2


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    Homework Helper

    General rule: The location of the pivot point is irrelevant to the final answer. in other words, you can put it anywhere you want and you'll get the same thing. This having been said, it's generally a good idea to put the pivot point at the location of an unknown force if you have more than one. If you only have one unknown, then put it at the location of a known one. The force at the location of the pivot cancels out of the torque equations.
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