11. A particle with charge Q is on the y axis a distance a from the origin and a particle with charge q is on the x axis a distance d from the origin. The value of d for which the x component of the force on the second particle is the greatest is:
(A)0
(B)a
(C)\( \sqrt{2}a \)
(D)a/2
(E)\( a/\sqrt{2} \)
答案:登入後查看
統計: 尚無統計資料
統計: 尚無統計資料