在图P4.9所示电路中,已知T₁~T₃管的特性完全相同,β＞＞2;反相输入端的输入电流为i_I1,同相输入端的输入电流为i_I2.试问:<img src='https://img2.soutiyun.com/ask/2021-01-09/979039538307596.png' />

在图4.4.1(a)和(b)所示的互补对称电路中，已知Vcc=6V，R_L=8Ω，假设三极管的饱和管压降U_CES=1V。 ①试估算电路的最大输出功率P_om; ②估算电路中直流电源消耗的功率P_V和效率η。 并将两个电路的估算结果进行比较。 <img src='https://img2.soutiyun.com/ask/2020-09-10/968622476866462.png' />

在图3-23所示的电路中，已知<img src='https://img2.soutiyun.com/ask/2020-11-14/974192768614519.png' />试求I₃。 <img src='https://img2.soutiyun.com/ask/2020-11-14/974192781086232.png' />

试用网孔分析求解图题8-10所示电路中的正弦稳态电流i₁(t)和i₂(t)。已知u_s(t)=9cos(5t)V。 <img src='https://img2.soutiyun.com/ask/2020-08-27/967411508475994.png' />

<img src='https://img2.soutiyun.com/ask/2020-09-11/9687068705288.png' />

<img src='https://img2.soutiyun.com/ask/2021-01-21/980070260607023.jpg' />

在图3.17所示电路中，已知R=2Ω，Z₁=-j10Ω，Z₂=(40+j30)Q，<img src='https://img2.soutiyun.com/ask/2020-12-15/976893137697925.png' /><img src='https://img2.soutiyun.com/ask/2020-12-15/976893148823561.png' /> <img src='https://img2.soutiyun.com/ask/2020-12-15/976893181116408.png' />

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' />

求图题11-6所示电路中的i₁和i₂，已知u_s(t)=100cos(10³+t+30°)V。 <img src='https://img2.soutiyun.com/ask/2020-08-31/967729012341469.png' />

在图10-6非对称式多谐振荡器电路中,已知G₁和G₂为74系列反相器7404,它们的输出高电平<img src='https://img2.soutiyun.com/ask/2020-12-25/977745494489401.png' />,输出低电平<img src='https://img2.soutiyun.com/ask/2020-12-25/977745585165587.png' />阈值电压<img src='https://img2.soutiyun.com/ask/2020-12-25/977745593373057.png' />输入钳位电压<img src='https://img2.soutiyun.com/ask/2020-12-25/977745603765651.png' />,内部电阻<img src='https://img2.soutiyun.com/ask/2020-12-25/977745616267366.png' />给定R=1.5kΩ,C=0.01μF,试求电路的振荡频率. <img src='https://img2.soutiyun.com/ask/2020-12-25/977745644900004.png' />

在图9-1所示机构中,已知:x=250mm,y=200mm,l_AS2=128mm,F为驱动力,Q为有效阻力.m₁=m₃=2.75kg,m₂=4.59kg,Js₂=0.0l2kg·m²,又原动件3以等速v=5m/s向下移动,试确定作用在各构件上的惯性力. <img src='https://img2.soutiyun.com/ask/2020-12-31/978270790835882.png' />

在图LP4-69所示的共集电极电路中,已知晶体三极管在I_CQ=2mA时的参数为r_bb=50Ω,<img src='https://img2.soutiyun.com/ask/2020-10-26/97255806712955.png' />试求高频电压传递函数<img src='https://img2.soutiyun.com/ask/2020-10-26/972558082050404.png' />的表示式. <img src='https://img2.soutiyun.com/ask/2020-10-26/972558092714014.png' />

<img src='https://img2.soutiyun.com/ask/2020-09-14/968971604757546.png' />

①试估算电压放大倍数和 <img src='https://img2.soutiyun.com/ask/2020-09-10/968621949195281.png' />输入、输出电阻R_i、R₀; ②如果不接旁路电容Ca，则=？ <img src='https://img2.soutiyun.com/ask/2020-09-10/968621959958897.png' />

题7-27图所示电路中，已知i_S=10e(t)A，R₁=1Ω，R₂=2Ω，C=1μF，u_C(0-)=2V，g=0.25s。求全响应i₁(t)、i_C(t)、u_C(t)。 <img src='https://img2.soutiyun.com/ask/2020-09-02/967900598791111.png' />

在图NP2-17(a)所示的T型匹配网络中，已知输出负载电阻为R_L，放大器要求的匹配阻抗为R_e。 <img src='https://img2.soutiyun.com/ask/2021-02-24/983011823810775.png' /> <img src='https://img2.soutiyun.com/ask/2021-02-24/983011845538018.png' />

<img src='https://img2.soutiyun.com/ask/2021-02-26/983184210538544.png' />

在图NT6-4所示锁相解调电路中，若将环路滤波器改为简单RC滤波器，则当环路的输入信号v_i(t)=V_imsin(ω_rt+M_fsin_Ωt)时，试证:为实现不失真解调，必须满足下列关系式<img src='https://img2.soutiyun.com/ask/2021-02-26/983187125725284.png' /> <img src='https://img2.soutiyun.com/ask/2021-02-26/983187147945554.png' />

<img src='https://img2.soutiyun.com/ask/2021-02-02/981108857928113.png' />

在图2-16所示结构中,已知个构件的长度,构件1以角速度<img src='https://img2.soutiyun.com/ask/2020-12-29/978113751128932.png' />₁逆时针方向回转.现已给出求受解机构在图示位置时构件5上E点的速度v_E的速度多边形图.试写出求解v_E的过程.(包括求解时所用的矢量方程式,各量的方向及大小的表达式) <img src='https://img2.soutiyun.com/ask/2020-12-29/978114330770086.png' />

(1)最大输出功率P_om和效率ƞ各为多少？ (2)晶体管的最大功耗P_Tmax为多少？ (3)为了使输出功率达到P_om,输入电压的有效值约为多少？ <img src='https://img2.soutiyun.com/ask/2021-01-09/97906063889348.png' /> 图p9.2

在图2-13所示的五杆机构中,已知各构件尺寸(尺寸比例尺u₁=0.001m/mm)和<img src='https://img2.soutiyun.com/ask/2020-12-29/978113751128932.png' />₁、<img src='https://img2.soutiyun.com/ask/2020-12-29/978113751128932.png' />₄的大小和方向.试用作图法分析构件2的角速度<img src='https://img2.soutiyun.com/ask/2020-12-29/978113751128932.png' />₂和角加速度<img src='https://img2.soutiyun.com/ask/2020-12-29/978114214119414.png' />₂. <img src='https://img2.soutiyun.com/ask/2020-12-29/978114010615774.png' />

<img src='https://img2.soutiyun.com/ask/2020-10-26/972564163704254.jpg' />

练习题6-5图所示RL电路，已知u_s(t)=12e(t)V试求阶跃响应i_L、u₁和u。 <img src='https://img2.soutiyun.com/ask/2020-08-25/967204134099058.png' />