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The two blocks in Figure P7.69 are connected by a massless rope that passes over a pulley. The pulley is 12 cm in diameter and has a mass of 2.0 kg. As the pulley turns, friction at the axle exerts a torque of magnitude 0.50 N · m. If the blocks are released from rest, how long does it take the 4.0 kg block to reach the floor?
Figure P7.69
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