题30图所示电路引入的反馈是（）。https://assets.asklib.com/psource/2015110209240014869.jpg

A . 串联电压负反馈 B . 串联电流负反馈 C . 并联电压负反馈 D . 串联电压正反馈

A . 串联电压负反馈 B . 正反馈 C . 并联电压负反馈

A .https://assets.asklib.com/psource/2015110209580674404.jpg B .https://assets.asklib.com/psource/2015110209582145651.jpg C .https://assets.asklib.com/psource/2015110209583531555.jpg D .https://assets.asklib.com/psource/2015110209584911393.jpg

A . 串联电流负反馈 B . 并联电流负反馈 C . 串联电压负反馈 D . 正反馈

<img src='https://img2.soutiyun.com/shangxueba/ask/17874001-17877000/17875143/2015110209075654816.jpg' /> A．15 B． 10 C． 7 D． 12

<img src='https://img2.soutiyun.com/ask/2020-10-09/971112968507991.png' /> <img src='https://img2.soutiyun.com/ask/2020-10-09/971112900716113.jpg' />

<img src='https://img2.soutiyun.com/shangxueba/ask/17862001-17865000/17862233/2015110209254329436.jpg' /> A．<img src='https://img2.soutiyun.com/shangxueba/ask/17862001-17865000/17862233/2015110209260250234.jpg' /> B．<img src='https://img2.soutiyun.com/shangxueba/ask/17862001-17865000/17862233/2015110209262636595.jpg' /> C．<img src='https://img2.soutiyun.com/shangxueba/ask/17862001-17865000/17862233/201511020926411982.jpg' /> D．<img src='https://img2.soutiyun.com/shangxueba/ask/17862001-17865000/17862233/2015110209265736798.jpg' />

已知题9-4图所示电路中u_s=16√2sin(ωt+30°)V，电流表A的读数为5A。ωL=4Ω，求电流表A₁、A₂的读数。 <img src='https://img2.soutiyun.com/ask/2020-11-30/975592647422898.png' />

<img src='https://img2.soutiyun.com/ask/2020-10-10/971172420596861.png' /> <img src='https://img2.soutiyun.com/ask/2020-10-10/971172435008685.jpg' />

为了用低值电阻实现高放大倍数的比例运算，常用T型电阻网络代替反馈电阻R_f，电路如下图所示，试证明<img src='https://img2.soutiyun.com/ask/2019-05-23/927450645342966.png' /><img src='https://img2.soutiyun.com/ask/2019-05-23/927450653422385.png' />

<img src='https://img2.soutiyun.com/ask/2019-04-22/92482398653108.png' /><img src='https://img2.soutiyun.com/ask/2019-04-22/924823993098692.png' />

<img src='https://img2.soutiyun.com/ask/uploadfile/5406001-5409000/c630e547205761d766a5a68bcf02d8c6.png' />

是 否

A、使输入电阻减小，输出电阻减小 B、使输入电阻增大，输出电阻增大 C、使输入电阻减小，输出电阻增大 D、使输入电阻增大，输出电阻减小

A．电流串联负反馈 B．电压并联负反馈 C．电流并联负反馈 D．电压串联负反馈

题8-16图所示电路中<img src='https://img2.soutiyun.com/ask/2020-09-02/967908620890949.png' />。求电压<img src='https://img2.soutiyun.com/ask/2020-09-02/967908643298231.png' />。 <img src='https://img2.soutiyun.com/ask/2020-09-02/967908658092077.png' />

<img src='https://img2.soutiyun.com/shangxueba/ask/17868001-17871000/17868863/2015110209404832241.jpg' /> A．1 B． -1 C． 2 D． -2

<img src='https://img2.soutiyun.com/shangxueba/ask/17868001-17871000/17868888/2015110209513078451.jpg' /> A．0.25 B． 0.5 C． 2 D． 4

证明<img src='https://img2.soutiyun.com/ask/2020-07-01/962449441023258.jpg' /> 并说明负反馈抑制干扰的能力。 <img src='https://img2.soutiyun.com/ask/2020-07-01/96244945329896.jpg' />