问题
选择题
交流发电机在工作时的电动势为
，若将其电枢的转速提高1倍，其他条件不变，则其电动势变为：（ ）
A．
B．2
C．2
D．
答案
答案：C
根据电动势E=NBSω，当转速提高1倍，则E′=2E，电动势变为2
，C正确。
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交流发电机在工作时的电动势为，若将其电枢的转速提高1倍，其他条件不变，则其电动势变为：（ ）
A．
B．2
C．2
D．
答案：C
根据电动势E=NBSω，当转速提高1倍，则E′=2E，电动势变为2，C正确。
| 选用下面框中的词汇完成句子，注意使用正确的形式及时态。 | |
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