一质量为m的带电液滴以竖直向下的初速度v0进入某电场中。由于静电

一质量为m的带电液滴以竖直向下的初速度v0进入某电场中。由于静电力和重力的作用,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.静电力力对液滴做的功为

B.液滴克服静电力做的功为+mgh

C.液滴的机械能减少mgh

D.液滴的机械能减少量为-mgh

答案

B

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