如图所示，AC、BD为圆的两条互相垂直的直径，圆心为O，半径为R．电荷量均为Q的正、负点电荷放在圆周上，它们的位置关于AC对称，+Q与O点的连线和OC间夹角为30°．下列说法正确的是_刷题宝

题干

如图所示，AC、BD为圆的两条互相垂直的直径，圆心为O，半径为R．电荷量均为Q的正、负点电荷放在圆周上，它们的位置关于AC对称，+Q与O点的连线和OC间夹角为30°．下列说法正确的是（）

A：O点的场强大小为 $\frac{\sqrt{3} k Q}{2 R^{2}}$

B：O点的场强大小为 $\frac{\sqrt{3} k Q}{R^{2}}$

C：B，D两点的电势关系是：ϕ_B＞ϕ_D

D：电荷量为+q的点电荷在A点的电势能小于在C点的电势能

上一题下一题 0.0难度选择题更新时间:2019-08-24 04:59:08

答案(点此获取答案解析）

C

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