問題詳情
20．a、b、c、d是匀强电场中的四个点，它们正好是一个矩形的四个顶点。电场线与矩形所在的平面平行。已知a点的电势是20V，b点的电势是24V，d点的电势是4V，如图。由此可知，c点的电势为（ ） 
(A)4V
(B)8V
(C)12V
(D)24V 第
(A)4V
(B)8V
(C)12V
(D)24V 第
參考答案
答案：B
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)
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