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A 1.0 kg block initially traveling at 6.0 m/s slides up an incline, reaching a vertical height of 0.40 m in 3.0 seconds. The block is still moving at 2.0 m/s when it reaches this higher point. The average power exerted by kinetic friction on the block during this segment of motion is W.
An ideal spring with k=8 N/m is initially compressed 0.40 m. One end is attached to a wall and the other is attached to a 1.0 kg block. The block is released from rest and slides 0.20 m on the horizontal surface before coming to rest (the spring is still compressed by 0.20 m at this time). The coefficient of kinetic friction between the block and surface is
An ideal spring hangs vertically from the ceiling. A 1.0 kg block is attached to the bottom end and released from rest with the spring initially unstretched. The block reaches its lowest point when the spring is stretched by 0.40 m. The spring constant is N/m.