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 fact underli1hpdpic-7p0fk b2 o9wes the operation of essentially all el4r qzn4uxuu 75ectric motors?quzx4u 5 nu74r
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
| 
