【单选题】
单结晶体管的结构中有___个基极。
A. 3
B. 4
C. 2
D. 1
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答案
C
解析
暂无解析
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【单选题】
单结晶体管在电路图中的文字符号是___。
A. SCR
B. VT
C. VD
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集成运放的输出级通常由___构成。
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D. 共集电极放大电路
【单选题】
理想集成运放输出电阻为___
A. 10Ω
B. 100Ω
C. OΩ
D. 1KΩ
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固定偏置共射极放大电路,已知RB=300KΩ,RC=4KΩ,Vcc=12V,β=50,则UCEQ为___V 。
A. 3
B. 6
C. 8
D. 4
【单选题】
分压式偏置共射放大电路,更换β大的管子,其静态值UCEQ会___
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固定偏置共射放大电路出现饱和失真,是___
A. Rc偏小
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多级放大电路之间,常用共集电极放大电路,是利用其___特性。
A. 输入电阻大、输出电阻小
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C. 输入电阻小、输出电阻小
D. 输入电阻大、输出电阻大
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共射极放大电路的输出电阻比共基极放大电路的输出电阻是___。
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能用于传递交流信号且具有阻抗匹配的耦合方式是___。
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【单选题】
要稳定输出电流,增大电路输入电阻应选用___负反馈。
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音频集成功率放大器的电源电压一般为___伏。
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RC选频振荡电路,当电路发生谐振时,选频电路的幅值为___。
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C. 2
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LC选频振荡电路达到谐振时,选频电路的相位移为___度。
A. 90
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串联型稳压电路的调整管接成___电路形式。
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单相半波可控整流电路电感性负载接续流二极管,α=90°时,输出电压Ud为___
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单相桥式可控整流电路电感性负载带续流二极管时,晶闸管的导通角为___
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单相桥式可控整流电路电感性负载,控制角α=60°时,输出电压Ud是___
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【单选题】
___触发电路输出尖脉冲。
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【单选题】
晶闸管两端___的目的是实现过压保护。
A. 串联快速熔断器
B. 并联快速熔断器
C. 并联压敏电阻
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This passage is primarily about __________.___
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D. To state the primary uses of TV.
【单选题】
Television, as a source of entertainment, is ________.___
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C. quite dangerous            
D. relatively cheap
【单选题】
Why are some people against TV?___
A. Because TV programs are not interesting.
B. Because TV viewers are totally passive.
C. Because TV prices are very high.
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【单选题】
One of the most obvious advantages of TV is that _________.___
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D. Beverage companies should be responsible for collecting and reusing discarded plastic soda bottles.
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【单选题】
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 The underlined word "they" in "... together they threaten to confuse." (Para.5) refers to ____________.___
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B. was designed and constructed in a scientific way
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【单选题】
What made the Ouchidas' new house a horrible dream?___
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B. Gas leakage in the kitchen.
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【单选题】
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Why were cracks in old houses not a big concern?___
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【单选题】
Which of the following could be used as a motivation to do our assignments?___
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【单选题】
What can help us to keep refreshed throughout the day?___
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【单选题】
Which of the following could be the best title for this article?___
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【单选题】
It is implied in the text that it is hard to ________.___
A. carry life learning though  
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According to the author, the schooling framework often ________.___
A. produces slow students with poor memories
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【单选题】
Life learners recognize that learning will not be difficult if they are _________.___
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【单选题】
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【单选题】
Through life learning, children ________.___
A. will grow without the assistance from parents
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