Sound
Sound is a type of energy which enable us to hear.
Sound travels in the form of wave to one place to another.
Sound is produced by vibrating bodies.
E.g.:
Drum- when you hit a drum with a stick the drum skin vibrates.
Bells: when you strike a bell the body vibrates.
Guitars: when you pluck the strings of the guitar the strings vibrate.
Vocal cords: vocal cords vibrate by the air to produce sound.
The transmission of sound occurs due to the a medium (by solid, liquid, gas).
There are two main types of sound
Audible sound Inaudible sound
Note: in vacuum sound do not travel because there are no particles or no medium.
Audible sound: - Is the sound of frequency which is audible to the human ear. The
frequency sound is usually b/w the 20Kz to20KHz.
2. Inaudible sound: - Is the sound of frequency which is not audible to the human ear.
The frequency of 20Hz and above 20 KHz.
20Hz = Can't be heard
20KHz = Not clear(heard).
Infrasonic: Sounds with frequencies below the human hearing range frequency =
20Hz.
E.g: Whale = below20Hz.
Elephant = 5-20Hz.
Rhinoceros = around 5Hz
Ultrasonic: sound with frequencies above the human hearing range frequency=20KHz
E.g:1.Medical imaging(ultrasonography):Doctor's use ultrasonic weaves to create
images of internal organs, tissues, and even monitor fetal development this is one of the
most common in real life application.
2.Industrial cleaning:
Ultrasonic cleaners use high-frequency vibration in liquid to remove dirt from
delicate items like jewelry, lenses or surged instruments.
3.Sonar (Sound Navigation and Ranging).
, 4.Non - Destructive Testing (NDT)
Engineers use ultrasonic waves to detect flaws inside metal structures without
damaging them.
Animals that use Ultrasound
Dolphins, Bats, Porpoises
These animals use ultrasound for :-
Echolocation, Navigation and hunting in darkness, Detecting prey and objects.
Oscillatory motion
Movement of an object here and there in its mean point or center in
regular time interval.
Time period: the time taken for one complete oscillation.
S.T unit = sec or Hz−1
t = 1/f
Frequency:- the number of oscillations that occurs per unit time.
no . of oscillations
Frequency:- Time
S.I unit =Hz(hertz)
Amplitude:- the maximum displacement from the equilibrium position.
Speed or Wave:- the rate at which the disturbance travels through the medium. It is related
to wavelength and frequency by the formula.
distance
Speed=
time
λ
V= (S.I unit =m/sec or MHz)
T
1
V= λ f (since T= F )
Vibration:- when oscillation happened speedily.
Wavelength:- A wavelength is the distance between two consecutive points on a wave that
are in the same phase, such as crest to crest or trough to trough. It is denoted by Greek
word or letter λ(lambda).
Sound travels in the form of wave.
Sound loudness α Aptitude α frequency.
Fundamental Characteristics of Wave
1. Wavelength
2. Frequency
3. Amplitude
4. Time Period and Wave Speed
Characteristics Definition Unit sign Fleance
Sound is a type of energy which enable us to hear.
Sound travels in the form of wave to one place to another.
Sound is produced by vibrating bodies.
E.g.:
Drum- when you hit a drum with a stick the drum skin vibrates.
Bells: when you strike a bell the body vibrates.
Guitars: when you pluck the strings of the guitar the strings vibrate.
Vocal cords: vocal cords vibrate by the air to produce sound.
The transmission of sound occurs due to the a medium (by solid, liquid, gas).
There are two main types of sound
Audible sound Inaudible sound
Note: in vacuum sound do not travel because there are no particles or no medium.
Audible sound: - Is the sound of frequency which is audible to the human ear. The
frequency sound is usually b/w the 20Kz to20KHz.
2. Inaudible sound: - Is the sound of frequency which is not audible to the human ear.
The frequency of 20Hz and above 20 KHz.
20Hz = Can't be heard
20KHz = Not clear(heard).
Infrasonic: Sounds with frequencies below the human hearing range frequency =
20Hz.
E.g: Whale = below20Hz.
Elephant = 5-20Hz.
Rhinoceros = around 5Hz
Ultrasonic: sound with frequencies above the human hearing range frequency=20KHz
E.g:1.Medical imaging(ultrasonography):Doctor's use ultrasonic weaves to create
images of internal organs, tissues, and even monitor fetal development this is one of the
most common in real life application.
2.Industrial cleaning:
Ultrasonic cleaners use high-frequency vibration in liquid to remove dirt from
delicate items like jewelry, lenses or surged instruments.
3.Sonar (Sound Navigation and Ranging).
, 4.Non - Destructive Testing (NDT)
Engineers use ultrasonic waves to detect flaws inside metal structures without
damaging them.
Animals that use Ultrasound
Dolphins, Bats, Porpoises
These animals use ultrasound for :-
Echolocation, Navigation and hunting in darkness, Detecting prey and objects.
Oscillatory motion
Movement of an object here and there in its mean point or center in
regular time interval.
Time period: the time taken for one complete oscillation.
S.T unit = sec or Hz−1
t = 1/f
Frequency:- the number of oscillations that occurs per unit time.
no . of oscillations
Frequency:- Time
S.I unit =Hz(hertz)
Amplitude:- the maximum displacement from the equilibrium position.
Speed or Wave:- the rate at which the disturbance travels through the medium. It is related
to wavelength and frequency by the formula.
distance
Speed=
time
λ
V= (S.I unit =m/sec or MHz)
T
1
V= λ f (since T= F )
Vibration:- when oscillation happened speedily.
Wavelength:- A wavelength is the distance between two consecutive points on a wave that
are in the same phase, such as crest to crest or trough to trough. It is denoted by Greek
word or letter λ(lambda).
Sound travels in the form of wave.
Sound loudness α Aptitude α frequency.
Fundamental Characteristics of Wave
1. Wavelength
2. Frequency
3. Amplitude
4. Time Period and Wave Speed
Characteristics Definition Unit sign Fleance
