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动量定理

> 如图，两车厢的质量相同，其中一个车厢内有一人拉动绳子使两车厢相互靠近．若不计绳子质量及车厢与轨道间的摩擦，下列对于哪个车厢里有人的判断，正确的是（） A．绳子的拉力较大的那一端车厢里有人 B．先到达两车中点的车厢里没有人 C．先开始运动的车厢里没有人 D．不去称量质量无法确定哪个车厢有人

问题：

发布时间：2020-03-13

如图，两车厢的质量相同，其中一个车厢内有一人拉动绳子使两车厢相互靠近．若不计绳子质量及车厢与轨道间的摩擦，下列对于哪个车厢里有人的判断，正确的是（）

A．绳子的拉力较大的那一端车厢里有人

B．先到达两车中点的车厢里没有人

C．先开始运动的车厢里没有人

D．不去称量质量无法确定哪个车厢有人

参考答案：

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