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Question:

71.0-kg painter is on a uniform 22.0-kg scaffold supported from above by ropes. How close to the left can he approach safely?

There is a 6.0-kg pail of paint to one side.How close to the left end can he approach safely? How close to the right end can he approach safely? Can someone help me with this problem, I keep working and reworking it and coming to the same answer. I must be consistently making the same mistake. If someone can help me work through it I would really appreciate it. The answers I got were:Left: dmin, left = .54mRight: dmin, right = .77m

Answer:

At the threshold of danger, the tension on the far rope reaches zero. (a) Distance from left edge = x; then summing moments about the left rope gives ΣM = 0 = 71.0kg * g * (1m - x) - 22.0kg * g * 2.0m - 6.0kg * g * 1m The g term cancels, and the rest solves to x = 0.296 m ? (b) Distance from right edge is X; summing about the right rope, and knowing the g terms will cancel, ΣM = 0 = 22.0kg * 2m + 6.0kg * 3m - 71.0kg * (1m - X) leads to X = 0.127 m ? Hope this helps!

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