IHS Acoustics and Sound

Question 1

What is the standard unit used to measure sound frequency?

Accepted Answer

Hertz (Hz)

Answer

Hertz (Hz) measures the number of complete sound wave cycles per second and is the universally accepted unit for sound frequency.

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

The decibel scale is logarithmic; each 10 dB increase represents a tenfold increase in intensity, so 20 dB equals 100 times the intensity of the reference level.

Question 3

Which frequency range is most critical for speech intelligibility?

Accepted Answer

500–4,000 Hz

Answer

The 500–4,000 Hz range contains the most important frequencies for speech intelligibility, encompassing the primary energy of most vowels and consonants.

Question 4

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

Accepted Answer

343 meters per second

Answer

Sound travels at approximately 343 meters per second (about 1,125 feet per second) through air under standard room-temperature conditions.

Question 5

Which of the following best describes a pure tone?

Accepted Answer

A single-frequency sinusoidal sound wave

Answer

A pure tone is a single-frequency, sinusoidal sound wave with no harmonics or overtones, analogous to the sound produced by a tuning fork.

IHS - International Hearing Society Practice Test

IHS - International Hearing Society Practice Test

IHS Acoustics and Sound