一道大学物理题,求电势和带电量.
一有厚度导体球壳A（内外部球径分别为R2,R3,R3>R2）,同心的罩在接地导体球B上（半径为R1）,现在给A球壳带负电-Q,求B球所带电荷Qb及A球所带所带电势Ua.
答案为Q(R1+R2)/(R1R2+R2R3-R1R3)和Q(R2-R1)/4πε.（R1R2+R2R3-R1R3）；求过程.
纠正一下答案为QR1R2/(R1R2+R2R3-R1R3)和Q(R2-R1)/[4πε(R1R2+R2R3-R1R3）]