fbpx

Floyd: MCQ in Power Amplifiers

(Last Updated On: August 22, 2019)
MCQ for Power Amplifiers

This is the Multiple Choice Questions in Power Amplifiers from the book Electronic Devices – Electron Flow Version and Conventional Current Version 8th Edition by Thomas L. Floyd. If you are looking for a reviewer in Electronics Engineering this will definitely help. I can assure you that this will be a great help in reviewing the book in preparation for your Board Exam. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.

Online Questions and Answers Topic Outline

  • MCQs in Power Amplifiers
  • MCQs in Class A Power Amplifier
  • MCQs in Class A Power Amplifier
  • MCQs in Class AB Push-Pull Amplifiers
  • MCQs in Class C Power Amplifier

Practice Exam Test Questions

Choose the letter of the best answer in each questions.

1. For BJT power transistors, the collector terminal is always connected to the transistor’s case

A) for easy circuit connection.

B) to prevent shorts.

C) because the collector terminal is the critical terminal for heat dissipation.

D) because the collector terminal is located nearest the case.

View Answer:

Answer: Option C

Solution:

2. Quiescent power is the power dissipation of a transistor

A) with no signal input.

B) with no load.

C) under full load.

D) along the dc load line.

View Answer:

Answer: Option A

Solution:

3. A class B amplifier operates in the linear region for

A) slightly more than 180° of the input cycle.

B) 360° of the input cycle.

C) slightly less than 180° of the input cycle.

D) much less than 180° of the input cycle.

View Answer:

Answer: Option C

Solution:

4. In a class AB amplifier, if the VBE drops are not matched to the diode drops or if the diodes are not in thermal equilibrium with the transistors, this can result in

A) a current mirror.

B) diode separation.

C) crossover distortion.

D) thermal runaway.

View Answer:

Answer: Option D

Solution:

5. Which amplifier is commonly used as a frequency multiplier?

A) class A

B) class B

C) class C

D) all of the above

View Answer:

Answer: Option C

Solution:

6. The least efficient amplifier among all classes is

A) class B.

B) class A.

C) class AB.

D) class C.

View Answer:

Answer: Option A

Solution:

7. A class A amplifier has a voltage gain of 30 and a current gain of 25. What is the power gain?

A) 30

B) 25

C) 1.2

D) 750

View Answer:

Answer: Option D

Solution:

8. You have an application for a power amplifier to operate on FM radio frequencies. The most likely choice would be a ______ amplifier.

A) class A

B) class B

C) class C

D) class AB

View Answer:

Answer: Option C

Solution:

9. A class A amplifier with RC = 3.3 kΩ and RE = 1.2 kΩ has a VCC = 20 V. Find IC(sat).

A) 4.4 mA

B) 6.1 mA

C) 16.7 mA

D) 20 mA

View Answer:

Answer: Option A

Solution:

10. Refer to Figure 7-1. The dc voltage on the collector, VC, is

MCQ in Power Amplifiers Fig. 01

Figure 7-1

A) 5.4 V.

B) 6.6 V.

C) 12 V.

D) 0 V.

View Answer:

Answer: Option A

Solution:

11. Refer to Figure 7-1. This amplifier is operating as a ______ amplifier.

A) class A

B) class B

C) class AB

D) class C

View Answer:

Answer: Option A

Solution:

12. Refer to Figure 7-2. This amplifier is operating as a ______ amplifier.

MCQs in Power Amplifiers Fig. 02

Figure 7-2

A) class A

B) class B

C) class AB

D) class C

View Answer:

Answer: Option C

Solution:

13. Refer to Figure 7-2. The approximate voltages on the base, collector, and emitter, respectively, are

A) 0.7 V, 6.8 V, 0 V.

B) 0 V, 0 V, 0 V.

C) 0.7 V, 15 V, 0 V.

D) 0.7 V, 0 V, 15 V.

View Answer:

Answer: Option C

Solution:

14. Refer to Figure 7-2. The maximum efficiency of this amplifier is

A) about 25%.

B) about 78%.

C) about 70%.

D) about 100%.

View Answer:

Answer: Option B

Solution:

15. Refer to Figure 7-3. Determine VB1.

MCQs in Power Amplifiers Fig. 03

Figure 7-3

A) 0 V

B) 0.7 V

C) 9.3 V

D) 10.7 V

View Answer:

Answer: Option D

Solution:

16. Refer to Figure 7-3. Calculate VB2.

A) 0 V

B) 0.7 V

C) 9.3 V

D) 10.7 V

View Answer:

Answer: Option C

Solution:

17. Refer to Figure 7-3. You have an oscilloscope across RL and it shows a zero signal voltage. The problem might be that

A) C3 is open.

B) BE1 is open.

C) BE2 is open.

D) R1 is open.

View Answer:

Answer: Option A

Solution:

18. Refer to Figure 7-3. You find that this amplifier only shows the negative alternation at the output. The possible trouble might be that

A) C3 is shorted.

B) BE1 is open.

C) BE2 is open.

D) R1 is open.

View Answer:

Answer: Option B

Solution:

19. Refer to Figure 7-3. You find that there is no output signal. You measure the dc voltage of Q1 emitter and find it equal to 0 V. The trouble might be

A) D1 is shorted.

B) D2 is shorted.

C) R1 is open.

D) no trouble, everything is normal.

View Answer:

Answer: Option C

Solution:

20. Refer to Figure 7-3. You find that there is an input signal on the base of Q1 and Q2. However, there is no output signal. You then measure the dc voltages on Q2 and find them to be all 0 V. The possible trouble might be

A) C3 is shorted.

B) C1 is open.

C) RL is shorted.

D) VCC is 0 V.

View Answer:

Answer: Option D

Solution:

21. A class C amplifier has a tank circuit in the output. The amplifier is conducting only 28°. The output voltage is

A) 0 V.

B) a dc value equal to VCC.

C) a sine wave.

D) a square wave with a frequency determined by the tank.

View Answer:

Answer: Option C

Solution:

22. In practice, the efficiency of a capacitively coupled class A amplifier is about _____%.

A) 25

B) 40

C) 70

D) 10

View Answer:

Answer: Option D

Solution:

23. The Q-point is at cutoff for class _____ operation.

A) A

B) B

C) C

D) AB

View Answer:

Answer: Option B

Solution:

24. Class _____ amplifiers are normally operated in a push-pull configuration in order to produce an output that is a replica of the input.

A) A

B) B

C) C

D) AB

View Answer:

Answer: Option D

Solution:

25. The maximum efficiency of a class B amplifier is _____ percent.

A) 50

B) 25

C) 70

D) 79

View Answer:

Answer: Option D

Solution:

26. A class _____ amplifier is biased slightly above cutoff and operates in the linear region for slightly more than 180º of the input cycle.

A) A

B) B

C) C

D) AB

View Answer:

Answer: Option D

Solution:

27. Which class of amplifier operates in the linear region for only a small part of the input cycle?

A) A

B) B

C) C

D) AB

View Answer:

Answer: Option C

Solution:

28. The principal advantage(s) of MOSFETs over BJTs is (are)

A) their biasing networks are simpler.

B) their drive requirements are simpler.

C) they can be connected in parallel for added drive capability.

D) all of the above

View Answer:

Answer: Option D

Solution:

29. The principal advantage(s) of BJTs over MOSFETs is (are) that

A) voltage drop across the transistor is important.

B) they are not as prone to ESD.

C) both of the above

D) none of the above

View Answer:

Answer: Option C

Solution:

30. The class _____ amplifier is biased below cutoff.

A) A

B) AB

C) B

D) C

View Answer:

Answer: Option C

Solution:

Check your work.

Complete List of Chapter Quiz in Floyd’s Electronic Devices

If you liked this, then please subscribe to our YouTube Channel for engineering video tutorials. You can also find us on Twitter and Facebook.

Add Comment

© 2014 PinoyBIX Engineering. © 2019 All Rights Reserved | How to Donate? | Follow me on Blogarama DMCA.com Protection Status
mcq in computer fundamentals
➡️ MCQ in Computer Fundamentals Series | ECE Board Exam
mcq in industrial electronics
➡️ MCQ in Industrial Electronics Series | ECE Board Exam
MCQ in Power Generators (Cells and Batteries) Part 5 | ECE Board Exam
➡️ MCQ in Power Generators, Sources, Principles, Applications Series | ECE Board Exam
mcq in electrical circuit
➡️ MCQ in Electrical Circuit Series | ECE Board Exam