This is the Multiple Choice Questions (MCQs) in Chapter 31: Acoustics, Audio, and High Fidelity from the book Teach Yourself Electricity and Electronics, 5th edition by Stan Gibilisco. If you are looking for a reviewer in Electronics Engineering this will definitely help you before taking the Board Exam.
Start Practice Exam Test Questions
1. Acoustics is important in the design of:
- A. Amplifier power supplies.
- B. Speaker enclosures.
- C. Cables that connect components of a hi-fi system together.
- D. Graphic equalizers.
2. Electromagnetic interference to a hi-fi amplifier can be caused by:
- A. A nearby radio broadcast station.
- B. Improperly designed receiving antennas.
- C. Excessive utility voltage.
- D. Improper balance between the left and right channels.
3. The midrange audio frequencies:
- A. Are halfway between the lowest and highest audible frequencies.
- B. Represent sounds whose volume levels are not too loud or too soft.
- C. Are above the treble range but below the bass range.
- D. Are between approximately 0.2 and 2 kHz.
4. An indoor concert hall such that sound reaches every listener’s ears perfectly at all audio frequencies requires:
- A. A suspended ceiling with acoustical tile completely covering it.
- B. Numerous baffles on the walls and ceiling.
- C. A level of engineering beyond reasonable expectation.
- D. Avoidance of excessive background noise.
5. A sound volume change of -3 dB represents:
- A. A doubling of acoustic power.
- B. A threefold increase in acoustic power.
- C. A tenfold increase in acoustic power.
- D. No change in acoustic power.
6. A sound whose wavelength is 6in in the air has a frequency of:
- A. 550 Hz.
- B. 1100 Hz.
- C. 2200 Hz.
- D. It is impossible to calculate from this information.
7. A sound wave that travels at 335 m per second has a frequency of:
- A. 335 Hz.
- B. 3350 Hz.
- C. 33.5 Hz.
- D. It is impossible to calculate from this information.
8. The relative phase of two acoustic waves, as they arrive at your ears, can affect:
- A. How loud the sound seems.
- B. The direction from which the sound seems to be coming.
- C. Both A and B.
- D. Neither A nor B.
9. In an acoustic sine wave:
- A. The frequency and phase are identical.
- B. The sound power is inversely proportional to the frequency.
- C. The sound power is directly proportional to the frequency.
- D. All of the sound power is concentrated at a single frequency.
10. Vinyl disks are:
- A. Susceptible to physical damage.
- B. Useful primarily in high-power sound systems.
- C. Digital media.
- D. Preferred for off-the-air sound recording.
11. If an amplifier introduces severe distortion in the waveforms of input signals, then that amplifier is:
- A. Not delivering enough power.
- B. Operating at the wrong frequency.
- C. Operating in a nonlinear fashion.
- D. Being underdriven.
12. If a 10-watt amplifier is used with speakers designed for a 100-watt amplifier:
- A. The speakers are capable of handling the amplifier output.
- B. The amplifier might be damaged by the speakers.
- C. Electromagnetic interference is likely to occur.
- D. The speakers are likely to produce distortion of the sound.
13. Which of the following frequencies cannot be received by an AM/FM tuner?
- A. 830 kHz.
- B. 95.7 kHz.
- C. 100.1 MHz.
- D. 107.3 MHz.
14. A woofer:
- A. Is especially useful for reproducing the sounds of barking dogs.
- B. Is designed to handle short, intense bursts of sound.
- C. Should not be used with a graphic equalizer.
- D. Is designed to reproduce low-frequency sounds.
15. Suppose you have an amateur radio station and its transmitter causes EMI to your hi-fi system. Which of the following would almost certainly not help?
- A. Buy a radio transmitter that works on the same frequencies with the same power output, but is made by a different manufacturer.
- B. Reduce the transmitter output power.
- C. Use shielded speaker wires in the hi-fi system.
- D. Move the radio transmitting antenna to a location farther away from the hi-fi system.
16. A tape recording head:
- A. Converts sound waves to radio signals.
- B. Converts sound waves to fluctuating electric current.
- C. Converts audio-frequency currents to a fluctuating magnetic field.
- D. Converts direct current to audio-frequency currents.
17. A microphone:
- A. Converts sound waves to radio signals.
- B. Converts sound waves to fluctuating electric current.
- C. Converts audio-frequency currents to a fluctuating magnetic field.
- D. Converts direct current to audio-frequency currents.
18. An audio mixer:
- A. Cannot match impedances.
- B. Cannot make an amplifier more powerful.
- C. Will eliminate EMI.
- D. Allows a microphone to be used as a speaker.
19. Which of the following media or devices use digital-to-analog conversion?
- A. A CD player.
- B. A speaker.
- C. A microphone.
- D. A vinyl disk.
20. Phase quadrature is sometimes used to:
- A. Increase the output from a microphone.
- B. Reduce the susceptibility of a hi-fi system to EMI.
- C. Create the illusion of four-channel stereo when there are really only two channels.
- D. Convert an analog signal to a digital signal, or vice-versa.
Post a Comment
EmoticonClick to see the code!
To insert emoticon you must added at least one space before the code.