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Homework Help: Design of a simple fence post remover

  1. Aug 16, 2009 #1
    Design of a simple fence post remover

    I have been given an assignment of designing a simple fence post remover. Here is what the question says.
    “A farmer wishes to remove several fence posts. Each post is buried 18 inches in the ground and will require a maximum force of 175lb to remove it. He can use his truck to develop the force but he needs to devise a method for their removal without breaking the posts. Design a method considering that the only material available is a strong rope and various pieces of wood of different size and length.”
    I am allowed to neglect the friction.
    I have planned to use two planks of wood as a support. The planks will be place on equal distances from the post and that distance will be of their height. The rope will be tied to one plank and will pass through the fence post (using a hole or hook in the post) and above the second plank and tied to the truck. But I am confused about 2 issues.
    1. Distribution of Force in the rope.
    2. Moments
    Please help A.S.A.P.
  2. jcsd
  3. Aug 16, 2009 #2
    Attached is the idea sketch

    Attached Files:

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