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In Figure 8-45 a 1.2-kg block is held at rest against a spring with a force constant k = 730 N/m. Initially, the spring is compressed a distance d When the block is released, it slides across a surface that is frictionless except for a rough patch of width 5.0 cm that has a coefficient of kinetic friction μk = 0.44. Find d such that the block’s speed after crossing the rough patch is2.3m/s
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