电子学(北京交通大学) 中国大学mooc答案满分完整版章节测试

1 电子学基础 第1单元测验

1、 What is the input resistance between terminals B and G in the circuit shown below? (The voltage vx is a test voltage with the input resistance Rin defined as Rin ≡ vx / ix.)

答案:

2、 A signal source has an open-circuit voltage of 10mV and a short-circuit current of 10μA. The source resistance is          kΩ
答案: 1

3、 An amplifier has a voltage gain of 100 V/V and a current gain of 1000 A/A.  The power gain in decibels is           dB
答案: 50

4、 An amplifier operating from a single 15-V supply provides a 12-V peak-to-peak sine-wave signal to a 1-kΩ load and draws negligible input current from the signal source. The dc current drawn from the 15-V supply is 8 mA. The power dissipated in the amplifier is              mW.
答案: 102

5、 The output voltage of a voltage amplifier has been found to decrease by 20% when a load resistance of 1 kΩ is connected. The value of the amplifier output resistance is              Ω
答案: 250

2 运算放大器 第2单元测验

1、 The circuit shown in Fig. (a) can be used to implement a transresistance amplifier. Find the value of the input resistance , the transresistance , and the output resistance  of the transresistance amplifier. If the signal source shown in Fig. (b) is connected to the input of the transresistance amplifier, find its output voltage.

答案:

2、 Use the idea presented in the figure below to design a weighted summer that providesWhich choice is correct?

答案:

3、 What is the output voltage of the following circuit?

答案:

4、 Assuming ideal op amps, what is the voltage gain and the input resistance?

答案: -10V/V, 10 kΩ

5、 The expression for the voltage gain of the following circuit is             .

答案:

6、 Consider an inverting amplifier with a nominal gain of 1000 constructed from an op amp with an input offset voltage of 3 mV and with output saturation levels of ±10 V.  The peak sine-wave input signal that can be applied without output clipping is            mV.(approximately)
答案: 7

7、 Consider an inverting amplifier circuit designed using an op amp and two resistors, R1 = 10 kΩ and R2 = 1 MΩ. If the op amp is specified to have an input bias current of 100 nA and an input offset current of 10 nA. The output dc offset voltage resulting is              V
答案: 0.1

8、 A noninverting amplifier with a gain of 200 uses an op amp having an input offset voltage of +2 mV. When the input is 0.01V, the output is          V
答案: 2.4

9、 An op amp connected in a closed-loop inverting con-figuration having a gain of 1000 V/V and using relatively small-valued resistors is measured with input grounded to have a dc output voltage of –1.4 V. Its input offset voltage is                      mV
答案: -1.4

10、 The op amp in the circuits shown below has offset voltage of 1mV, the output voltage is            V.
答案: 5.005