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> 如图所示，将质量m=2kg的一个小钢球（可看成质点）从离地面H=2m高处由静止开始释放，落人泥潭并陷入泥中h=5cm深处，不计空气阻力（g取10m/s 2），则下列说法正确的是（　　） A．整个过程中重力做功为40J B．整个过程中重力做功为41J C．泥对小钢球的平均阻力为800N D．泥对小钢球的平均阻力为820N

问题：

发布时间：2024-09-12

如图所示，将质量m=2kg的一个小钢球（可看成质点）从离地面H=2m高处由静止开始释放，落人泥潭并陷入泥中h=5cm深处，不计空气阻力（g取10m/s ²），则下列说法正确的是（　　）

A．整个过程中重力做功为40J

B．整个过程中重力做功为41J

C．泥对小钢球的平均阻力为800N

D．泥对小钢球的平均阻力为820N

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