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> 质量为2kg的物体在光滑水平面上受到与水平方向成30°角的拉力F=3N的作用，经过10s（取g=10m/s 2） [ ] A．力F的冲量为30N·s B．物体的动量的变化是30kg·m/s C．重力的冲量是零 D．弹力的冲量是18N·s

问题：

发布时间：2024-09-12

质量为2kg的物体在光滑水平面上受到与水平方向成30°角的拉力F=3N的作用，经过10s（取g=10m/s ²）
[ ]
A．力F的冲量为30N·s
B．物体的动量的变化是30kg·m/s
C．重力的冲量是零
D．弹力的冲量是18N·s

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