电路如图 4 所示，电流 I 为 。http://image.zhihuishu.com/zhs/onlineexam/ueditor/201804/48dcfd6292e44a329c2d5b04973679d8.png
举一反三
- 电路如图4所示，电流I为。<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201804/48dcfd6292e44a329c2d5b04973679d8.png" /> A: 0A B: –2.5A C: 3A D: –3A
- 电路如图5所示，运算放大器构成 。http://image.zhihuishu.com/zhs/onlineexam/ueditor/201804/ad0dc8cc2e8547ccb31a035a818c1d8d.png
- 已知电路如图 4 所示，运算放大器构成http://image.zhihuishu.com/zhs/onlineexam/ueditor/201804/0547d1e3e7b44b5d8201447c92ed6e29.png
- 如图所示电路中的电流I为（）。http://image.zhihuishu.com/zhs/onlineexam/ueditor/201804/c8058a61bb7a4d17aff3c25f16756370.png
- 电路如图5所示，若输入信号ui为方波，则输出波形为 。http://image.zhihuishu.com/zhs/onlineexam/ueditor/201804/ad0dc8cc2e8547ccb31a035a818c1d8d.png