IHS Acoustics and Sound

Question 1

What is the standard unit used to measure sound frequency?

Accepted Answer

Hertz (Hz)

Answer

Decibel (dB)

Answer

Pascal (Pa)

Answer

Watt (W)

Question 2

Compared to a 0 dB SPL reference, a 20 dB SPL sound is how many times more intense?

Accepted Answer

100 times

Answer

2 times

Answer

10 times

Answer

1,000 times

Question 3

Which frequency range is most critical for speech intelligibility?

Accepted Answer

500–4,000 Hz

Answer

125–500 Hz

Answer

4,000–8,000 Hz

Answer

8,000–12,000 Hz

Question 4

Approximately how fast does sound travel through air at 20°C (68°F)?

Accepted Answer

343 meters per second

Answer

760 meters per second

Answer

1,125 meters per second

Answer

1,500 meters per second

Question 5

Which of the following best describes a pure tone?

Accepted Answer

A single-frequency sinusoidal sound wave

Answer

A broadband noise signal spanning all frequencies

Answer

A complex waveform with multiple harmonics

Answer

A tone consisting of two simultaneous frequencies

Question 6

What is the mathematical relationship between the frequency and wavelength of a sound wave?

Accepted Answer

Inversely proportional

Answer

Directly proportional

Answer

Exponentially proportional

Answer

Independent of each other

Question 7

What is the commonly cited threshold of pain for sound pressure level in humans?

Accepted Answer

140 dB SPL

Answer

85 dB SPL

Answer

100 dB SPL

Answer

120 dB SPL