【单选题】【消耗次数:1】
机械特性指的是电机的电磁转矩和转速间的关系,下边以他励和串励电机为例说明。
正确
错误
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相关题目
【判断题】 交流发电机的励磁方法为:先他励,后自励。()
①  正确
②  错误
【判断题】 直流电机励磁绕组不与电枢连接,励磁电流由独立的电源供给,称为他励电机。
①  正确
②  错误
【单选题】 关于他励直流发电机功率关系说法正确的是:()。
①  <imgwidth="235"height="60"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD12038.png">
②  <imgwidth="215"height="60"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD12148.png">
③  <imgwidth="247"height="60"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD12260.png">
【单选题】 关于他励直流发电机功率关系说法正确的是:()。
【单选题】 起动机中直流串励电机的功能是( )
①  将电能转变为机械能;
②  将机械能变为电能;
③  将电能变为化学能。
【判断题】 机械特性表征转速和电磁转矩的关系,直流电动机的机械特性是一条直线。
①  正确
②  错误
【单选题】 直流发电机中电磁转矩与转速方向?
①  相同
②  相反
③  两者都是
④  都不是
【单选题】 并励直流发电机的电磁功率与输出功率之差等于()
①  励磁铜耗和转子铜耗之和
②  铁耗和附加损耗之和
③  +
【单选题】 交流发电机所采用的励磁方法是( )。
①  自励
②  他励
③  先他励后自励
【单选题】 负载运行的凸极同步发电机,励磁绕组突然断线,则电磁功率为零 。
①  正确
②  错误
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【单选题】 A: Can you keep an eye on my bag? B: [填空] A: No. Im going to the bathroom.
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④  Hi, John. This is Linda
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【单选题】 A: Shall we go out for dinner tonight? B: [填空].
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②  Have a nice time
③  Thats a good idea
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②  Turn it over
③  Keep it down
④  Bring it up
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①  Sorry to keep you out
②  Many happy returns of the day
③  Youre too polite
④  Me too
【单选题】 A: [填空]. Where was I? B: You were talking about your trip to South Africa.
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①  It doesnt matter
②  Thank you just the same
③  Do as you please
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【单选题】 A: Would you rather watch TV or go for a walk? B: The TV program is good today. [填空] A: Cool. Lets go.
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④  You know what I mean.