Sound and Its Measurement

Question 1

Types of Sounds

Answer 1

Spectral components, Duration, Periodicity

Question 2

the simplest type of sound

Answer 2

Pure tone

Question 3

It is periodic (repeat themselves at regular and equal intervals in time)
It results from simple harmonic motion that leads to sinusoidal disturbance in the medium
It is continuous sound

Answer 3

Pure tone

Question 4

They contain more than one frequency

They can be periodic or aperoidic (noise)

Answer 4

Complex Tones

Question 5

They can be formed by a proper combination of pure tones

Answer 5

Periodic Complex Tones

Question 6

is the lowest frequency, by which the object vibrates

Answer 6

Fundamental frequency

Question 7

The integral multiples of the F0 are

Answer 7

harmonics

Question 8

Is a mathematical method by which the periodic complex sound can be decomposited into a series of pure tones, the lowest frequency of which is called F0 and the integral multiple are harmonics (f1, f2, f3,…)

Answer 8

Fourier Analysis

Question 9

They contain two more frequencies that are not related to each other, not integral numbers
They can be continuous sounds that propagate for long duration as in noise/ hissing sound
Or transient with very short duration

Answer 9

Aperiodic Complex Tones

Question 10

They have very short duration

They are non-periodic sounds

Answer 10

Transient Sounds

Question 11

is defined as undesirable or unwanted sound signal

Answer 11

Noise

Question 12

used to depict the propagation of sound over time

Answer 12

Waveform

Question 13

What is the human range of hearing in terms of these two parameters

Answer 13

20 Hz to 20,000 Hz or 20 kHz.

Question 14

reflects how sensitivity to sound changes across the range of hearing.

Answer 14

Audibility curve

Question 15

difference between the threshold of hearing and the threshold of feeling is

Answer 15

“Dynamic range” is the difference between the lowest and highest sound intensities we can hear. Dynamic range is measured in decibels (dB).

Question 16

Normal hearing individual have a dynamic range up to

Answer 16

90 dB

Question 17

is a phenomenon, in which the system works with maximum efficiency with the least amount of force applied to set it into vibration and keep its motion

Answer 17

Resonance

Question 18

the frequency by which the object vibrates freely with minimal force applied

Answer 18

resonant frequency

Question 19

A tuning fork (fork1) is struck into a table, the fork will vibrate by its original (resonance) frequency and this is called

Answer 19

free vibration

Question 20

If this fork came in the vicinity of another tuning fork (fork2) that is close in its resonance frequency; this fork 2 will be forced into vibration

Answer 20

forced vibration

Question 21

act as filters; they filter out some frequencies and maintain others according to their resonant frequency.

Answer 21

Acoustic resonators

Question 22

The resonant frequency of a resonator depends on its

Answer 22

volume. The smaller the volume, the higher is the resonant frequency and vice veers.

Question 23

Are the resonator that are observed in the mechanical system, in which a vibrating object sets (forces) another object into vibration assuming that the two objects have equal or close resonance frequency

Answer 23

Mechanical Resonators