题干

如图所示,一导线折成动长为a的正三角形闭合回路,虚线MN右侧有磁感应强度为B的匀强磁场,方向垂直于回路所在的平面,回路以速度v向右匀速进入磁场,边长CD始终与MN垂直,从D点到达边界开始到C点进入磁场为止,下列结论中正确的是(   )

A:导线框受到安培力方向始终向上

B:导线框受到安培力方向始终向下

C:感应电动势的最大值为 32Bav

D:感应电动势平均值为 34Bav

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答案(点此获取答案解析)

C,D

同类题4

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