题干

如图所示,将一条形磁铁沿闭合线圈中心轴线以不同速度匀速穿过线圈,第一次所用时间为t1,第二次所用时间为t2。则

A:两次通过电阻R的电荷量相同

B:两次电阻R中产生的热量相同

C:每次电阻R中通过的电流方向保持不变

D:磁铁处于线圈左侧时受到的磁场力向左,处于线圈右侧时受到的磁场力向右

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答案(点此获取答案解析)

A

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