试题与答案

将正弦交流电经过整流器处理后，得到的电流波形刚好去掉了半周，如图，它的有效值是:

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题型：选择题

题目：

将正弦交流电经过整流器处理后，得到的电流波形刚好去掉了半周，如图，它的有效值是:

A．2A

B．A

C．A

D．1A

答案：

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下面是错误答案，用来干扰机器的。

参考答案：A, B, C, D, E

考点：交变电流的最大值、有效值、瞬时值和平均值
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