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动量定理

> 现代技术常用的“水刀”是将水从高压水枪中射出，形成一个很细的水束，水喷射速度达到2000m/s ，它被用来切割各种物体。“水刀”能切割物体是因为水 A．有很大的动能 B．有很大的动量 C．和物体接触时有很大的动量变化 D．和物体接触时单位面积上的动量变化率很大

问题：

发布时间：2024-09-10

现代技术常用的“水刀”是将水从高压水枪中射出，形成一个很细的水束，水喷射速度达到2000m/s ，它被用来切割各种物体。“水刀”能切割物体是因为水

A．有很大的动能

B．有很大的动量

C．和物体接触时有很大的动量变化

D．和物体接触时单位面积上的动量变化率很大

参考答案：

提问用户：NI***4Es

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