Block and tackle.

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(A)Mechanics - A+80: Mechanical Advantage

Block and Tackle. Block and Tackle: the Mechanical Advantage is 4, thus W2=4W1 for there to be equilibrium. If W1 > .25W2, then W1 goes down and W2 is lifted up.
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A+80+30
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A+80+40 Block and tackle: Bosun's chair.