问题 选择题

决定电路中感应电动势的大小的是穿过这一电路的(  D  )

A.磁场

B.磁通量

C.磁通量变化量

D.磁通量变化率

答案

答案:D

磁通量的变化率指的是磁通量的变化量和所用时间的比值;△φ/t

1磁通量的变化率是表示磁通量的变化快慢的物理量;

2磁通量的变化率由磁通量的变化量和时间共同决定;

3磁通量变化率大,感应电动势就大

阅读理解

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