题干

如图所示为一速度选择器,内有一磁感应强度为B,方向垂直纸面向外的匀强磁场,一束粒子流以速度v水平射入,为使粒子流经磁场时不偏转(不计重力),则磁场
区域内必须同时存在一个匀强电场,关于这个电场的场强大小和方向的说法中,正确的是

A:大小为B/v,粒子带正电时,方向向上

B:大小为B/v,粒子带负电时,方向向下

C:大小为Bv,方向向下,与粒子带何种电荷无关

D:大小为Bv,方向向上,与粒子带何种电荷无关

上一题 下一题 0.0难度 选择题 更新时间:2016-03-22 05:55:23

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D

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