【单选题】【消耗次数：1】
在三相交流电路的不对称星型连接中，中线的作用是
①
使不对称的相电流保持对称
②
使不对称的相电压保持对称
③
使输出功率更大
④
线电压与相电压同相
参考答案：
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相关题目
【单选题】
在三相交流电路中，当负载为对称且星型连接时，线电压与相电压的相位关系是
①
线电压超前相电压30度
②
线电压滞后相电压30度
③
线电压与相电压同相
④
线电压与相电压反相
【单选题】
在三相交流电路中，当负载为对称且三角型连接时，线电流与相电流的相位关系是
①
线电压超前相电压300
②
线电压滞后相电压300
③
线电流超前相电流300
④
线电流滞后相电流300
随机题目
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Well done. Congratulations on your success.
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Thank you very much
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Oh, no, no
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No, I didn’t do very well
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Sorry, I couldn’t any better
【单选题】
Good morning, sir. May I help you?
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No, I don’t buy anything
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No, I don’t need your help
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Yes, I need some sugar
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Oh, no. That’s OK
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I’d like to take you to the coffee house on the corner.
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Thank you. You shouldn’t’ do that
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Thanks, I’d like to go with you
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No, you can’t say so
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No, no, You can’t do that
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He’s determined to finish the job __________ long it takes.
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no matter
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however
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wherever
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whatever
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-- Could I speak to John Harris, please.
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Oh, how are you
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I’m John
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I’m listening
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Why don’t you travel to New York on vacation?
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I don’t want to go
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Excuse me, because I can’t
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I want to, but I haven’t got enough money
④
Because I’m going to school today
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Could you help me with my homework, please?
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No, no way
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No, I couldn’t
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No, I can’t
④
Sorry I can’t. I have to go to a meeting right now
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Determined to __________ as if everything were normal, he responded with a kind of indifference.
①
carry on
②
account for
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bring up
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Mary, your dress is really beautiful. How is John?
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Thank you very much
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No, no, John is not bad
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Thank you. He is fine
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Don’t say that. It’s ugly. John is good
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Excuse me, sir. Where is Dr. Brown’s office?
①
You can’t ask me
②
Pardon? I have no idea
③
Please don’t say so
④
Sorry I don’t know, but you can ask the man over there