Meaning of sound
The generation and propagation of a
sound
Sound created from a vibrating string
Nature of sound
Sound pro...
 is a disturbance that is transported
through a medium via the mechanism
of particle-to- particle interaction.

 is a wa...
 The vibrations of the object set particles
in the surrounding medium in vibration
motion, thus transporting energy throu...
Compressions are regions of high air pressure.
Rarefactions are regions of low air pressure.
 The diagram below depicts a...
1. There is a medium that carries the disturbance
from one location to another.
2. There is an original source of the wave...
 refers to “how often” the air particles vibrate.

 The sensation of a frequency is commonly referred
to as the pitch of...
 Any sound with a frequency below the audible
range of hearing(i.e., less than 20 Hz) is known as an
infrasound and any s...
 The amount of energy that is transported past a given area of the
medium per unit of time is known as the intensity of t...
 The scale for measuring intensity is the decibel
scale.
 The faintest sound that a human ear can detect is
known as the...
v = 331 m/s + (0.6 m/s/C)•T
Medium
Air

Speed of sound, (m/s)
330

Seawater

1 540

Freshwater

1 410

Brass

3 650

Copper

4 000

Wood

4 650

Steel...
1. Reflection of Sound
 Reflection of sound waves off of surfaces can
lead to one of two phenomena - an echo or a
reverbe...
2. Refraction of Sound
 Sound waves are known to refract when
traveling over water.
3. Diffraction of Sound Waves
 Sound waves moving around corners or edges.

4. Interference of Sound Waves
5. Beat
 refers to the rate at which the volume is heard to
be oscillating from high to low volume.
 can be described as the effect produced by a
moving source of waves in which there is an apparent
upward shift in freque...
Sample Problem:
On a hot summer day, a pesky little
mosquito produced its warning sound near your
ear. The sound is produc...
Check Your Understanding
Identify the following statements whether TRUE
or
FALSE.
1. A sound wave is a mechanical wave.
2....
6. Intense sounds are usually perceived as loud
sounds.
7. The speed of a sound wave depends upon its
frequency and its wa...
Sound
Sound
Sound
Sound
Sound
Sound
Sound
Sound
Upcoming SlideShare
Loading in …5
×

Sound

5,609 views

Published on

Published in: Technology, Business
2 Comments
4 Likes
Statistics
Notes
  • I DONT LIKE THIS POWERPOINT
       Reply 
    Are you sure you want to  Yes  No
    Your message goes here
  • i didn;'t like this . This is a lie
       Reply 
    Are you sure you want to  Yes  No
    Your message goes here
No Downloads
Views
Total views
5,609
On SlideShare
0
From Embeds
0
Number of Embeds
37
Actions
Shares
0
Downloads
260
Comments
2
Likes
4
Embeds 0
No embeds

No notes for slide

Sound

  1. 1. Meaning of sound The generation and propagation of a sound Sound created from a vibrating string Nature of sound Sound properties and their perception Amplitude and intensity Speed of sound indifferent media Behavior of sound Doppler effect
  2. 2.  is a disturbance that is transported through a medium via the mechanism of particle-to- particle interaction.  is a wave that is created by vibrating objects and propagated through a medium from one location to another.  is a mechanical wave.
  3. 3.  The vibrations of the object set particles in the surrounding medium in vibration motion, thus transporting energy through the medium. For a sound wave traveling through air, the vibrations of the particles are best described as longitudinal.
  4. 4. Compressions are regions of high air pressure. Rarefactions are regions of low air pressure.  The diagram below depicts a sound wave created by a tuning fork and propagated through the air in an open tube.
  5. 5. 1. There is a medium that carries the disturbance from one location to another. 2. There is an original source of the wave, some vibrating object capable of disturbing the first particle of the medium. 3. The sound wave is transported from one location to another by means of particle-to-particle interaction.
  6. 6.  refers to “how often” the air particles vibrate.  The sensation of a frequency is commonly referred to as the pitch of a sound.  A high pitch sound corresponds to a high frequency sound wave and a low pitch sound corresponds to a low frequency sound wave.
  7. 7.  Any sound with a frequency below the audible range of hearing(i.e., less than 20 Hz) is known as an infrasound and any sound with a frequency above the audible range of hearing (i.e., more than 20 000 Hz) is known as an ultrasound. Hearing Capacity Dogs ( 50 Hz – 45 000 Hz ) Cats ( 45 Hz – 85 000 Hz ) Bats ( > 120 000 Hz ) Dolphins ( > 200 000 Hz ) Elephant ( 5 Hz – 10 000 Hz ) Human ( 20 Hz – 20 000 Hz )
  8. 8.  The amount of energy that is transported past a given area of the medium per unit of time is known as the intensity of the sound wave.  The greater the amplitude of vibrations of the particles of the medium, the greater the rate at which energy is transported through it, and the more intense that the sound wave is.  Intensity is the energy/time/area; and since the energy/time ratio is equivalent to the quantity power, intensity is simply the power/area.  Typical units for expressing the intensity of a sound wave are Watts/meter2.
  9. 9.  The scale for measuring intensity is the decibel scale.  The faintest sound that a human ear can detect is known as the threshold of hearing.  While the intensity of a sound is a very objective quantity that can be measured with sensitive instrumentation, theloudness of a sound is more of a subjective response that will vary with a number of factors.  Despite the distinction between intensity and loudness, it is safe to state that the more intense sounds will be perceived to be the loudest sounds.
  10. 10. v = 331 m/s + (0.6 m/s/C)•T
  11. 11. Medium Air Speed of sound, (m/s) 330 Seawater 1 540 Freshwater 1 410 Brass 3 650 Copper 4 000 Wood 4 650 Steel 4 950 Iron 5 000 Aluminum 5 140 Glass (soda) 5 150 (Vacuum) -0-
  12. 12. 1. Reflection of Sound  Reflection of sound waves off of surfaces can lead to one of two phenomena - an echo or a reverberation.  An echo is produced in an empty room.  A reverberation often occurs in a small room with height, width, and length dimensions of approximately 17 meters or less.
  13. 13. 2. Refraction of Sound  Sound waves are known to refract when traveling over water.
  14. 14. 3. Diffraction of Sound Waves  Sound waves moving around corners or edges. 4. Interference of Sound Waves
  15. 15. 5. Beat  refers to the rate at which the volume is heard to be oscillating from high to low volume.
  16. 16.  can be described as the effect produced by a moving source of waves in which there is an apparent upward shift in frequency for the observer and the source are approaching and an apparent downward shift in frequency when the observer and the source is receding.
  17. 17. Sample Problem: On a hot summer day, a pesky little mosquito produced its warning sound near your ear. The sound is produced by the beating of its wings at a rate of about 600 wing beats per second. a. What is the frequency in Hertz of the sound wave? b. Assuming the sound wave moves with a velocity of 350 m/s, what is the wavelength of the wave?
  18. 18. Check Your Understanding Identify the following statements whether TRUE or FALSE. 1. A sound wave is a mechanical wave. 2. A sound wave is a means of transporting energy without transporting matter. 3. Sound can travel through a vacuum. 4. A sound wave is a transverse wave. 5. To hear the sound of a tuning fork, the tines of the fork must move air from the fork to one's ear.
  19. 19. 6. Intense sounds are usually perceived as loud sounds. 7. The speed of a sound wave depends upon its frequency and its wavelength. 8. Sound waves would travel faster on a warm day than a cool day. 9. A high pitched sound has a low wavelength. 10.Ultrasound waves are those sound waves with frequencies less than 20 Hz.

×