Coast Guard Exams
Question 584Deck General70% to pass

The greatest strain, when lifting a load with the jumbo purchase, is on _______________.

AI Explanation
The correct answer is B) the hauling part because it must absorb the frictional losses of all the sheaves. In a jumbo purchase system, the hauling part is the line that the operator pulls to lift the load. This line must overcome the frictional losses of all the sheaves (pulleys) in the system, which creates the greatest strain on this part of the rigging. The standing part (the line directly connected to the load) does not experience this additional strain from the sheave friction. The other options are incorrect because: A) the standing part does not experience the greatest strain, C) the parts in the movable block do not experience the greatest strain, and D) the load is not equally divided among all the parts.

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