What is the mechanical advantage of a Gun tackle?

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Multiple Choice

What is the mechanical advantage of a Gun tackle?

Explanation:
The main idea is that mechanical advantage equals how many rope segments are directly supporting the load. In a gun tackle, three rope segments bear on the moving block (to which the load is attached), so the upward force from the rope is three times the tension you apply. That means, in an ideal system (neglecting friction and pulleys’ weight), a pulling effort equal to one-third of the load will hold or lift it, giving a 3:1 purchase. This setup uses the rope path to create that extra supporting strand on the moving block, increasing the gain beyond a simple 2:1 arrangement but not reaching the four-part systems. Real-world factors like friction and rope/pulley weight will reduce the effective MA slightly.

The main idea is that mechanical advantage equals how many rope segments are directly supporting the load. In a gun tackle, three rope segments bear on the moving block (to which the load is attached), so the upward force from the rope is three times the tension you apply. That means, in an ideal system (neglecting friction and pulleys’ weight), a pulling effort equal to one-third of the load will hold or lift it, giving a 3:1 purchase. This setup uses the rope path to create that extra supporting strand on the moving block, increasing the gain beyond a simple 2:1 arrangement but not reaching the four-part systems. Real-world factors like friction and rope/pulley weight will reduce the effective MA slightly.

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