问题 选择题

一个矩形线圈在匀强磁场中匀角速度转动,产生的交变电动势的瞬时表达式为e=10sin4πtV,则:

A.该交变电动势的频率为2Hz

B.t=0s时刻线圈平面与磁场平行

C.t=0.25s时,e达到最大值

D.在1s时间内,线圈中电流方向改变100次

答案

答案:A

本题考查的是交流电的相关问题,根据交流电表达式可知,该交变电动势的频率为2Hz,A正确;t=0s时刻线圈平面与磁场垂直,B错误;t=0.125s时,e达到最大值,C错误;在1s时间内,线圈中电流方向改变2次,D错误;

完形填空
完形填空。
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