Test Bank for Introduction to Audiology, 13th Edition

Chapter 2 Sound and Its Measurement Sound may be regarded objectively if we consider its waves in terms of their frequency, intensity, phase, and spectrum. Sounds may also be studied subjectively, in terms of pitch, loudness, or the interactions of signals producing masking or localization. In discussing sound energy it is always important to specify precisely the various aspects and appropriate measurement references, such as hertz, decibels (IL, SPL, HL, or SL), mels, sones, or phons. LEARNING OBJECTIVES Understanding this chapter requires no special knowledge of mathematics or physics, although a background in either or both of these disciplines is surely helpful. From this chapter, readers should be able to 2.1 Describe sound waves and their common attributes, and express the way these characteristics are measured. 2.1 Discuss the basic interrelationships among the measurements of sound and demonstrate the ability to perform simple calculations (although at this point it is more important to grasp the physical concepts of sound than to gain skill in working equations). 2.2 Understand the different references for the decibel and when they are used. 2.3 State the difference between physical acoustics and psychoacoustics. 2.4 Discuss the reasons for audiometer calibration and what this may entail in general terms. Vocabulary Items American National Standards Institute Aperiodic Artificial mastoid Bel Cancellation Components Amplitude Artificial ear Beats Brownian motion Complex wave Compression 1 Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved Cosine wave Decibel Elasticity Force Formant Free vibration Fundamental frequency Hearing level Intensity International Organization for Standardization Joule Localization Longitudinal waves Loudness level Mass reactance Newton Ohm Overtones Phase Pitch Power Quality Ratio Resonance Sensation level Sinusoidal Sound pressure level Stiffness Threshold Velocity Watts Waves Damping Dyne Erg Forced vibration Fourier analysis Frequency Harmonics Hertz Intensity level Inverse square law Kinetic energy Logarithm Loudness Mass Microbar Octave Oscillation Period Phon Potential Pressure Rarefaction Reactance Resonant frequency Sinewaves Sound level meter Spectrum Stiffness reactance Transverse wave Vibration Wavelength Work 2 Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved Chapter 2 Test Items Essay Questions 1. Describe what is meant by Sound Pressure Level, Hearing Level and Sensation Level and how these are used. 2. How would you calibrate an audiometer for air conduction and bone conduction, both with and without electroacoustic equipment? Short Answer Questions 1. Sound travels through air in the form of ____. 2. Three types of waves discussed in this book are ____, ____, and ____. 3. Waves are described as a series of ____ and ____. 4 Two types of vibration described above are ____ and ____ 5. The two major effects on frequency are ____ and ____. 6. The velocity of sound is its ____. 7. The formula for wavelength is ____. 8. The number of beats per second is determined by the difference between two ____. 9. The lowest frequency of vibration in a complex sound is called the ____. 10. Formant frequencies of the human voice are determined by the ____. 11. Two sine waves may be contrasted by their differences in ____, ____, and ____. 12. Decibels cannot be simply added or subtracted because they are ____. 3 Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved 13. The decibel reference on audiometers is ____. 14. Any discussion of decibels must include their ____. 15. The psychological correlate of frequency is ____. 16. The ability to localize sound requires that the individual have ____. 17. The threshold shift of one sound that is caused by the introduction of a second sound is called ____. 18. Audiometer earphones are used to test hearing by ____. 19. An oscillator is placed on the forehead or mastoid to test hearing by ____. 20. The decibel reference used in sound-level meters is ____. Multiple Choice Questions 1. The zero dB reference level for most sound level meters is a. 20 dynes per cm squared b. 20 micropascals c. 0 dB d. 40 watts 2. One parameter not looked at in electroacoustic calibration of audiometers is a. frequency b. intensity c. duration of tonal presentation d. attenuator linearity 3. The alternating regions of low pressure and high pressure produced by an object’s vibration are called, respectively: a. constructive, destructive b. rarefactions, condensations c. condensations, compressions d. troughs, valleys 4 Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved 4. When a sound source produces energy at more than one frequency, the result is a _____ sound. a. sinusoidal b. simple c. loud d. complex 5. The reference value for sound power is: a. 10-16 watt/cm2 b. 10-4 watts/cm2 c. 20Pa d. 10-12 dynes/cm2 6. A complex sound is found to have the following frequency components: 100 Hz, 200 Hz, 300 Hz, 400 Hz, and 500 Hz. Its fundamental frequency is: a. 50 Hz b. 100 Hz c. 300 Hz d. 500 Hz 7. Complete cancellation of a sound may occur when a _____ encounters a _____ a. rarefaction, rarefaction b. condensation, condensation c. rarefaction, condensation d. deflection, reflection 8. An object has one frequency at which it will vibrate at its greatest amplitude. This frequency is known as the _____ a. peak amplitude b resonant frequency c. octave frequency d. harmonic frequency 9. Frequency and intensity are ______ measurements of sound. a. physical b. perceptual c. intuitive d. reflective 10. Pitch and Loudness are ___________ measurements of sound. a. physical 5 Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved b. reflective c. intuitive d. perceptual 11. The amount of time it takes a waveform to complete one cycle is called its ______ a. wavelength b. phase c. period d. duration 12. The _____ of a sine wave is determined by the number of cycles completed in one second. a. phase b. frequency c. duration d. wavelength 13. An increase of _____ dB corresponds to a doubling of sound pressure. a. 2 b. 4 c. 6 d. 12 14. At its resonant frequency, a mass vibrates a. With the least amount of applied energy b. With the greatest amount of applied energy c. At its least possible amplitude d. As a free vibration 15. The velocity of sound in air is said to be a. 20 mph b. 1130 ft/sec c. 5286 ft/sec d. 14.7 mph 16. The period of a sound can be calculated as a. Period = 1/frequency b. Period = frequency/1 c. Period = 1/π d. Period = frequency/20Pa 17. Masking may take place when a. The masker precedes the signal 6 Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved b. The signal precedes the masker c. The masker and signal coexist in time d. All of the above 18. If the fifth harmonic of a sound is 500 HZ, the fundamental frequency is a. Indeterminable from the above information b. Determined by wavelength c. 100 Hz d. 250 Hz 19. The unit of measurement in equal loudness contorus is a. mel b. sone c. decibel d. phon 20. The period of a 100 Hz tone is a. 1/1000 sec b. 1/100 sec c. 1/10 sec d. 1 sec 7 Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved Chapter 2 Test Item Answer Key Essay Items 1. In addition to defining SPL, HL and SL, the student’s answer should show an understanding how these relate for audiometric testing. 2. A complete response should include discussion of the different purposes between an artificial ear and artificial mastoid and the need for intensity level calibration as well as frequency and attenuator linearity calibration. The response should include mention of the different couplers for supra-aural earphones and insert receivers as well as acknowledgement that the SPL to reach audiometric zero differs for these two transducers and what this means clinically. Finally, recognition of the difference between electroacoustic calibration and biologic calibration and the need for both should be demonstrated in the answer. Short Answer Items 1. waves 2. transverse, longitudinal, sine 3. compressions, rarefactions 4. forced, free 5. mass, stiffness 6. speed 7. w=v/f 8. frequencies 9. fundamental frequency 10. vocal tract 11. frequency, intensity, phase 12. logarithmic 13. Hearing Level (HL) 14. references 15. pitch 16. similar hearing sensitivity in both ears 17. masking 18. air conduction 19. bone conduction 20. sound-pressure level Multiple Choice Items 1. 2. 3. 4. 5. 6. 7. b c b d a b c 8. b 9. a 10. d 11. c 12. b 13. c 14. a 15. b 16. a 17. d 18. c 19. d 20. b 8 Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved 2 Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved