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动量定理

> 一质量为m的滑块沿光滑的水平面以速度V 0运动．遇到竖直的墙壁被反弹回来，返回的速度变为 1 2 V 0，则以下说法正确的是（　　） A．滑块的动量改变量的大小为 1 2 mV0 B．滑块的动量改变量的大小为 3 2 mV0 C．滑块的动量改变量的方向与V0的方向相反 D．重力对滑块的冲量为零

问题：

发布时间：2024-09-10

一质量为m的滑块沿光滑的水平面以速度V ₀运动．遇到竖直的墙壁被反弹回来，返回的速度变为

1

2

V ₀，则以下说法正确的是（　　）

A．滑块的动量改变量的大小为

1

2

mV0

B．滑块的动量改变量的大小为

3

2

mV0

C．滑块的动量改变量的方向与V₀的方向相反

D．重力对滑块的冲量为零

参考答案：

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