I always struggled to gain intuition about how pulley problems, so I asked my physics major friends for help. One of them delivered (and then some).

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	A wooden block, A, slides on a frictionless table when pulled by a hanging box, B, using the pulley system shown in the figure below. If the mass of the wooden block is 4.0 kg, the mass of the hanging box is 5.0 kg, and the pulley system (both the string and the pulleys) are massless, what is the acceleration of block A as it slides on the table?

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