Introduction to Electronics complete course is currently being offered by Georgia Institute of Technology through Coursera platform and is taught by: Dr. Bonnie H. Ferri and Dr. Robert Allen Robinson, Jr.

This course introduces students to the basic components of electronics: diodes, transistors, and op amps. It covers the basic operation and some common applications.
Introduction to Electronics Week 2 Quiz Answers
Q 1)

Introduction to Electronics Week 4 Quiz Answers

Introduction to Electronics Week 5 Quiz Answers

Question 1)

Consider a diode circuit shown below.

Assume that each diode can be modeled as an ideal diode in series with a voltage source, having Vf=0.7V.

The resistor has a value of R1=10Î©.

Check all statements that are true

• When any of the diodes are ON, the voltage across that diode is 0.7 V.
• When Vin is in between the positive and negative limits of Vout, Vo=Vin.
• If V1=2.3V and V2=2.3V, then Vo has a positive limit of 3 Volts and a negative limit of -3 Volts.
• When R1 is replaced with a resistor with higher resistance, the Voltage Transfer Characteristics (VTC) curve changes.

Question 2)

Which of the following are TRUE? Select all that apply.

• To have a smoother output voltage from an ac to dc converter, one must use a smaller filter capacitor.
• The order of stages in a DC power supply from input to output is a transformer, rectifier, then lastly a filter.
• If the input is a sinusoidal signal, the output of a half-wave rectifier will have the same frequency as the input.
• If the input is a sinusoidal signal, the output of a full-wave rectifier will have the same frequency as the input.
• If the diodes in the rectifiers are non-ideal, the output voltage of a full-wave rectifier is smaller than that of a half-wave rectifier.

Question 3)

A limiter is implemented using two non-ideal diodes, each modeled as an ideal diode in series with a voltage Vf volts. If the input voltage is a 5V amplitude sine wave, what is the minimum output voltage?

• 2Vf
• ​−5
• Vf
• ​-5 + 2Vf

Question 4)

In the rectifier below, the resistance Rs of the voltage source has been included to see how it affects the output voltage. If R=300Î©, RS= 100Î©, and Vin  is a sinusoidal voltage with amplitude 10V, what is the maximum output voltage Vout in volts?

The diodes are ideal.

(It may help to redraw the circuit with diodes replaced by short and open circuits as appropriate)

Question 5)

For the circuit shown and the given input voltage, which of the following plots is the correct output voltage versus time? The diode in the circuit is modeled as an ideal diode in series with a voltage source Vf = 0.65V.

• D
• C
• A
• B

Question 6)

A diode circuit and sinusoidal input signal are shown. The diode is modeled as an ideal diode in series with a voltage source Vf = 0.7V.

What value resistor should be used so that the maximum diode current is 10 mA? Give your answer in ohms to the nearest ohm.

Question 7)

For the circuit and input of problem 6:

If R = 510 â„¦, what is the magnitude of the diode current at t = 400Î¼s? Give your answer in milliamps.

Question 8)

For the circuit and input of problem 6:

If R = 510 â„¦, what is the magnitude of the diode current at t = 700Î¼s? Give your answer in milliamps.

Question 9)

Select all of the statements that are NOT true.

• Loading of a voltage source may be reduced by lowering the source resistance.
• A diode circuit with three regions of operation (three states) has three corners on its VTC plot.
• The envelope of an AM voltage waveform is a plot of the peak voltage of the carrier signal versus frequency.
• A diode envelope detector with a relatively large time constant can act as a peak detector.
• The voltage transfer characteristic of an ideal voltage regulator is a line of slope 1.

Question 10)

For the input and output waveforms shown, which of these sets of (Vin, Vout) points contains only points that are on the VTC?

• 0.5,2) (3,3) (-2,0)
• (1.5,5) (0.5,0.5) (3,2)
• (0,0) (5,2) (-0.5,0)
• (-2,-1) (0,0) (4,2)

Introduction to Electronics Week 6 Quiz Answers

Question 1)

In the n-channel MOSFET circuit, RD = 12kÎ©, and the supply voltage VDD = 10V.

The transistor has the parameters K = 1.56mA/V2 and VTO = 1.4V.

What must the gate voltage VG be to set the drain voltage VD to 5V ?

Question 2)

A portion of a common source amplifier is shown in the figure. It is given that the source voltage VS = -4V,

Determine the dc bias current through R3.(in mA)

Question 3)

For the partial CS amplifier circuit of problem 2,

Determine the dc bias current through RS. (in mA)

Question 4)

For the partial CS amplifier circuit of problem 2,

Determine the dc bias current of the transistor ID. (in mA)

Question 5)

The binary inputs to the circuit below are A = 1, B = 0. Enter the corresponding value of C.

Question 6)

The binary inputs to the circuit below are A = 0, B = 0, D = 0. Enter the corresponding value of E.

Question 7)

For the CS amplifier shown, VDD = 15V, VSS = -15V, K = 1.1mA/V2, VTO = 2V, R = 15kohm,

What is the dc gate voltage to two decimal places?

Question 8)

For the CS amplifier of problem 7, what is the MOSFET drain current in mA to two decimal places?

Question 9)

For the CS amplifier of problem 7, what is the dc drain voltage VD in volts to two decimal places?

Question 10)

For the CS amplifier of problem 7, what is the magnitude of the ac midband gain to two decimal places?

Introduction to Electronics Week 7 Quiz Answers

Q 1)

The dc bias circuit for a common emitter amplifier is shown in the figure. In the circuit,

VCC = 12V, RB2 = 105.8kÎ©, VC = 6V, VE = 3V, VB = 3.65V, IE = 2mA, and B = 75.

Q 2)

For the circuit of question 1,

Solve for the collector resistor RC. (In kilo ohms to two decimal places)

Q 3)

For the circuit of question 1,

Solve for the base bias resistor RB1. (In kilo ohms to two decimal places)

Q 4)

In the CE amplifier shown,

Solve for the collector current in milliamps to two decimal places.

Q 5)

For the CE amplifier of question 4, solve for the midband gain to one decimal place.

Q 6)

In the BJT CE amplifier of question 4, as the emitter resistor RE2 is increased,

• the midband gain increases and the dc collector current increases.
• the midband gain increases and the dc collector current decreases.
• the midband gain decreases and the dc collector current remains constant.
• the midband gain decreases and the bias point of the transistor changes.

Q 7)

Select all of the below statements that are true.

• A CE amplifier may behave as an attenuator for signals at some frequencies.
• As the collector current of a particular biased BJT is decreased, its transconductance decreases.
• The overdrive factor used when designing a BJT switch is to ensure that the BJT remains in cutoff no matter what load is placed on the switch.
• The saturation current parameter of a BJT may be determined from a point on its transfer characteristic curve.
• A curve tracer may be used to measure the collector current of a BJT for different values of VCE as the base current is held constant.