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| 1 | Sound waves are longitudinal waves that require a medium for transmission. |
 | A) | True |
| B) | False |
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| 2 | If a tree falls in a forest, there is no sound unless an ear can pick up the vibrations. |
| A) | True |
| B) | False |
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| 3 | Sound waves travel faster in air than in metals because the air is less dense. |
| A) | True |
| B) | False |
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| 4 | The speed of sound is increased significantly with rising temperatures. |
| A) | True |
| B) | False |
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| 5 | The quality of different sounds is demonstrated by the difference in tones when a C note is sounded on a flute, a violin, and a trumpet. |
| A) | True |
| B) | False |
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| 6 | A sound of intensity level 40 dB is twice as intense as a sound of 20 dB. |
| A) | True |
| B) | False |
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| 7 | Sound that fluctuates in intensity because of the simultaneous output of two sources is a consequence primarily of the Doppler effect. |
| A) | True |
| B) | False |
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| 8 | In applying Doppler’s equation, speeds are reckoned as positive for speeds of approach and negative for speeds of recession. |
| A) | True |
| B) | False |
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| 9 | Opening the end of a closed pipe will double the frequency produced. |
| A) | True |
| B) | False |
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| 10 | The speed of sound in gases is larger for the gases with higher molecular masses. |
| A) | True |
| B) | False |
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| 11 | The speed of sound is greatest when the medium is |
| A) | a vacuum |
| B) | air |
| C) | water |
| D) | metal |
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| 12 | Which of the following is a sensory effect rather than a measurable physical quantity? |
| A) | Frequency |
| B) | Quality |
| C) | Intensity |
| D) | Waveform |
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| 13 | For a closed pipe, the second overtone is the |
| A) | second harmonic |
| B) | third harmonic |
| C) | fourth harmonic |
| D) | fifth harmonic |
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| 14 | The physical property that is most responsible for resonance is |
| A) | waveform |
| B) | frequency |
| C) | quality |
| D) | intensity |
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| 15 | Which of the following sounds is loudest? |
| A) | 40 dB |
| B) | 10-5M
µW/cm² |
| C) | 10-10 W/m² |
| D) | 3 B |
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| 16 | The speed of sound in air at 0°C is 331 m/s. Its speed at 30°C is approximately |
| A) | 331 m/s |
| B) | 343 m/s |
| C) | 349 m/s |
| D) | 350 m/s |
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| 17 | The fundamental frequency for a 20-cm closed pipe when the speed of sound is 340 m/s is |
| A) | 4.25 Hz |
| B) | 8.25 Hz |
| C) | 425 Hz |
| D) | 825 Hz |
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| 18 | The intensity level in decibels of a sound whose intensity is 2 X -10-6µW/cm² is approximately |
| A) | 27 dB |
| B) | 43 dB |
| C) | 50 dB |
| D) | 103 dB |
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| 19 | A car horn emits sound at a frequency of 200 Hz. The pitch heard when the car is moving at 31 m/s toward an observer in air at 0°C is approximately |
| A) | 221 Hz |
| B) | 219 Hz |
| C) | 181 Hz |
| D) | 183 Hz |
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| 20 | Two tuning forks of 340 and 343 Hz are sounded together. The resulting beats per second will be |
| A) | 1 |
| B) | 2 |
| C) | 3 |
| D) | 4 |
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| 21 | The closed end of a pipe must be a displacement ; the open end must be a displacement . |
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| 22 | The velocity of sound waves in a liquid is equal to the square root of the ratio of its to its . |
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| 23 | The three physical properties of sound that correspond to loudness, pitch, and quality are , , and , respectively. |
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| 24 | The represents the standard zero of sound intensity. Its value is W/cm². |
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| 25 | Sound waves having frequencies below the range of audible sound are termed ; sounds having frequencies above this range are termed . |
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| 26 | For a closed pipe, only the harmonics are possible. Thus, the seventh harmonic will be the overtone. |
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| 27 | The power transmitted by a sound wave through a unit of area is a measure of . |
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| 28 | The refers to the apparent change in frequency of a source of sound when there is relative motion between the source and the observer. The pitch heard by an observer is when a sound approaches her or him and when the sound leaves. |
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| 29 | Beats are the product of alternating and interference of sound waves of slightly different frequency. |
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| 30 | When the intensity I1 of one sound is 10 times as great as the intensity I2 of another, the difference in intensity levels is said to be 1 . |