题干
—Hello! May I speak to Lucy，please?
—Sorry，I’m afraid you have the wrong ．
—Sorry，I’m afraid you have the wrong ．
A：way
B：name
C：number
D：telephone
答案(点此获取答案解析）
C
沿垂直于电场方向射入平行板之间，则带电粒子在电场区域内运动的轨迹是(设负极板B固定不动，带电粒子始终不与极板相碰)（ ） 