图(甲)所示的实验表明__________导体在磁场中会受到力的作用;依据图(乙)所揭示的实验原理可以制成___________________。
通电;发电机
--Sally is a middle school girl. She is in Class 6, Grade 7. How old is she?
--______[ ]
A. The thirteen.
B. Thirteenth.
C. Thirty.
D. Thirteen.
电动机匝间短路会引起电机()温升过高。