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    "The wall is smooth and the floor is rough",
    "θ is the angle with the floor",
    "Not a person on the ladder, a rough wall, a wedge, a screw, or a belt"
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      "title": "Hibbeler, Engineering Mechanics: Statics",
      "section": "Dry friction — ladder against a smooth wall",
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        "convention": "Uniform ladder, weight at mid-length. θ is the angle with the floor. The wall is smooth. F is the floor friction toward the wall, N is the floor normal, and B is the wall reaction. μ_min = F/N."
      },
      "tol": 1e-9
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