半径为R1和R2(R2>R1)的两无限长同轴圆柱面,单位长度上分别带有电量q和-q,试求:(1)r

问题描述:

半径为R1和R2(R2>R1)的两无限长同轴圆柱面,单位长度上分别带有电量q和-q,试求:(1)r