电路如图所示，20Ω电阻两端的电压U（ ）。http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/37eeb8f471b14fa39bd164502652fd41.png
举一反三
- 电路如图所示，20Ω电阻两端的电压U（ ）。<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/37eeb8f471b14fa39bd164502652fd41.png" /> A: -40V B: 20V C: 30V D: 10V
- 源电压放大倍数与电压放大倍数的关系是 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/2f6b445b00df4646b4edacaddd79a7af.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/4a0b0c930f934ecdb98e4d8b0c3fe3b4.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/d873f32851bf4ff196a2acbb25974b7e.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/a5405728c76b40e9ba50a7cf3fd20f7b.png" />
- 理想运算放大器的主要特征为 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/8ec216c374814f48ad60b00627bee3d6.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/b36e9dfc39a748b1b652e9b3c1a762ed.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/2a93dfdbeb804030ac0da51eed08943e.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/a01ee7baba84489f886c43cc5d5c5169.png" />
- 图示有侧移结构，设横梁的水平侧移为<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/5b1b0d2260734afd9d372476eccd0a52.png"/>，计算约束状态下杆件的固端弯矩，正确的是（ ）<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/0bb431e37a424b1f841ad9350d80f241.png"/> A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/ef65ff72dc6b4179bee92ce4ff148aad.png"/> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/5ca987b52284485a986cb954a09b51a0.png"/> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/0c7f5a6de2714ac0bbb5a243d9b8da4b.png"/> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/94aab58ed2f94f90af7c4ea00aecf764.png"/>
- 负反馈系统的开环传递函数为<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/a7ed7837bacb42a0bc3a3b685f1f59ca.png" />，若要绘制参数<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/20abe260498a4ba4ac78f48ef331ea76.png" />的根轨迹，其等效开环传递函数应该是（ ）。 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/3fd90fdfd9534f81b6f4b6052f381f27.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/c39a9d3fb81b47bead514a12c4ad843d.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/916d03716ed144c58426442cc710f9fa.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/2f2d63241a46476a9ece1e3ccd8e96e5.png" />