本题目来源于试卷: Physics Unit20: Magnetism，类别为 通用国际物理
[单选题]
What fundamental fac6 7 f. a vjfg): tgaudt4hq+l.mpzng+9t underlies the operation of essentially all electric motorlme puy4,t( tpflps ;tb0b*-wxv 2;+gs+tt tbl4l ,sgxbw u(v0 pp*;fe-mp2y;?
A. Opposite electric charges attract and like charges repel.
B. A current-carrying conductor placed perpendicular to a magnetic field will experience a force.
C. Alternating current and direct current are both capable of doing work.
D. Iron is the only element that is magnetic.
E. A magnetic north pole carries a positive electric charge, and a magnetic south pole carries a negative electric charge.
参考答案: B
本题详细解析:
暂无
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