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> 一质量为m的带电液滴以竖直向下的初速度v 0进入某电场中．由于电场力和重力的作用，液滴沿竖直方向下落一段距离h后，速度为0．以下判断正确的是（　　） A．电场力对液滴做的功为 1 2 mv 20 B．液滴克服电场力做的功为 1 2 mv 20 +mgh C．液滴的机械能减少mgh D．电场力对液滴的冲量大小为mv0

问题：

发布时间：2024-09-09

一质量为m的带电液滴以竖直向下的初速度v ₀进入某电场中．由于电场力和重力的作用，液滴沿竖直方向下落一段距离h后，速度为0．以下判断正确的是（　　）

A．电场力对液滴做的功为

1

2

mv 20

B．液滴克服电场力做的功为

1

2

mv 20

+mgh

C．液滴的机械能减少mgh

D．电场力对液滴的冲量大小为mv₀

参考答案：

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