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> 起重机将质量为m=5x10 3 kg的物体由静止竖直吊起，起吊过程中做匀加速直线运动a=0.2m/s 2，当起重机输出功率达到其允许的最大时，保持该功率直到重物以V m=1.02m/s做匀速运动，g="10" m/s 2，不计其他额外功（1）、起重机允许输出的最大功率（2）、重物做匀加速运动所经历的时间和起重机在第2秒末的输出功率

问题：

发布时间：2024-09-12

起重机将质量为m=5x10 ³ kg的物体由静止竖直吊起，起吊过程中做匀加速直线运动a=0.2m/s ²，当起重机输出功率达到其允许的最大时，保持该功率直到重物以V _m=1.02m/s做匀速运动，g="10" m/s ²，不计其他额外功
（1）、起重机允许输出的最大功率
（2）、重物做匀加速运动所经历的时间和起重机在第2秒末的输出功率

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