题图7-8（a)所示单口网络可以等效为题图7-8（b)所示的单口网络，试求等效电感L和等效电容C的数值。

A . 1点 B . 2点 C . 3点 D . 4点

A . 1点 B . 2点 C . 3点 D . 4点

若题图所示电路中二端口网络的A参数已知，则11&39;端口的输入电阻Z_in=______。 <img src='https://img2.soutiyun.com/ask/5499001-5502000/7cc3154445ed13f2c39a3500448c50d8.jpg' />

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电路如题图5-7所示，已知电源电压为正弦电压，电流I₁=I₂=10A，试<img src='https://img2.soutiyun.com/ask/2021-01-03/978529327380181.png' />和<img src='https://img2.soutiyun.com/ask/2021-01-03/978529340109909.png' />，设<img src='https://img2.soutiyun.com/ask/2021-01-03/978529340109909.png' />的初相角为零。 <img src='https://img2.soutiyun.com/ask/2021-01-03/978529357270891.png' />

如题图3-2所示，在边长为a的正方形的顶点上，分别有质量为m的4个质点，质点之间用轻质杆连接，求此系统绕下列转轴的转动惯量: <img src='https://img2.soutiyun.com/ask/2020-04-03/954753207114551.png' /> (1)通过其中一个质点A，并平行于对角线BD的转轴; (2)通过质点A并垂直于质点所在平面的转轴。

<img src='https://img2.soutiyun.com/ask/2020-07-06/962894436190544.png' /><img src='https://img2.soutiyun.com/ask/2020-07-06/962894441876869.png' />

题图10-50所示单口网络工作于正弦稳态，已知us(t)=<img src='https://img2.soutiyun.com/ask/2020-07-07/96297017944186.png' />试求单口网络的戴维宁等效电路。 <img src='https://img2.soutiyun.com/ask/2020-07-07/962970193210647.png' /><img src='https://img2.soutiyun.com/ask/2020-07-07/962970201021094.png' /><img src='https://img2.soutiyun.com/ask/2020-07-07/962970211392687.png' />

试证明题图13-17(a)所示耦合电感的电压电流关系，在k=1和L1变为无穷大时，会变成题图13-17(b)所示理想变压器的电压电流关系。 <img src='https://img2.soutiyun.com/ask/2020-07-08/963047437573226.png' />

在题图所示电路中，F与A、B的逻辑关系是() <img src='https://img2.soutiyun.com//1/2021-05-26/990876016471773.png' /> <img src='https://img2.soutiyun.com//1/2021-05-26/990876028690504.png' />

试写出题图12-4(a)、(b)所示双口网络的转移电流比，并用计算机程序画出电阻R=1kΩ和电容C=1μF时电路的幅频特性曲线。 <img src='https://img2.soutiyun.com/ask/2020-07-07/962979932609709.png' /><img src='https://img2.soutiyun.com/ask/2020-07-07/962979942033248.png' /><img src='https://img2.soutiyun.com/ask/2020-07-07/962979947940586.png' /><img src='https://img2.soutiyun.com/ask/2020-07-07/962979953660913.png' /><img src='https://img2.soutiyun.com/ask/2020-07-07/962979959421242.png' />

在圆柱形空间内有一-磁感应强度为B的均匀磁场,如题图10. 1(5)所示,B的大小均匀减小,有一弧形导线<img src='https://img2.soutiyun.com/ask/2020-04-07/955120586552917.jpg' />如图放置,下述正确的是() <img src='https://img2.soutiyun.com/ask/2020-04-07/955120627014368.jpg' /> A.<img src='https://img2.soutiyun.com/ask/2020-04-07/955120668347352.jpg' /> B.<img src='https://img2.soutiyun.com/ask/2020-04-07/955120720159102.jpg' /> C.<img src='https://img2.soutiyun.com/ask/2020-04-07/955120766873058.jpg' /> D.<img src='https://img2.soutiyun.com/ask/2020-04-07/955120793043421.jpg' />

题图8-9所示电路中，开关在a点为时已久，t=0时开关倒向b点，试求t≥0时的电容电压uC(t)和电感电流iL(1)。 <img src='https://img2.soutiyun.com/ask/2020-07-07/962962293498809.png' />

<img src='https://img2.soutiyun.com/ask/5166001-5169000/3ebd1625a9a7dfba676ca32ec09e6099.jpg' />

有如下定义： int b[10]={1,2,3,4,5,6,7,8,9,10},*q=b; 则数值为8的表达式是()。 A．*q+8 B．*(q+7) C． *q+=8 D．q+7

<img src='https://img2.soutiyun.com/ask/2020-07-07/962978361111824.png' /><img src='https://img2.soutiyun.com/ask/2020-07-07/962978376321694.png' /><img src='https://img2.soutiyun.com/ask/2020-07-07/962978383913128.png' />

<img src='https://img2.soutiyun.com/ask/2020-07-07/962980707934055.png' /><img src='https://img2.soutiyun.com/ask/2020-07-07/962980722925912.png' />

<img src='https://img2.soutiyun.com/shangxueba/ask/18093001-18096000/18095888/2016031714334914854.jpg' /> A．低通滤波器 B． 高通滤波器 C． 带通滤波器 D． 带阻滤波器

(1)A、B板上的电荷分别在P点产生的场强E_A、E_B; (2)A、B板上的电荷在P点产生的合场强E; (3)拿走B板后P点处的场强E'。 <img src='https://img2.soutiyun.com/ask/2020-10-09/971112721135842.jpg' />

题图5-6(a)(b)分别为10MHz和25MHz的晶体振荡器。试画出交流等效电路，说明晶体在电路中的作用，并计算反馈系数。 <img src='https://img2.soutiyun.com/ask/2020-08-28/967471398192681.png' />

<img src='https://img2.soutiyun.com/ask/2020-07-06/962892737449381.png' /><img src='https://img2.soutiyun.com/ask/2020-07-06/96289274775397.png' />