The document discusses sound waves as longitudinal waves created by vibrating objects, which travel through various media and are perceived by the human ear. It details the properties of sound, such as speed, frequency range, and the phenomena of reflection, refraction, and energy flow measured in decibels. The speed of sound is affected by the medium's elasticity, density, and environmental conditions like temperature and altitude.

1. By Prof. Liwayway Memije-Cruz

2.  a wave that is created by
vibrating objects and
propagated through a
medium from one location
to another
 refers to the physical
sensation that stimulates
our ears. In constructing
sound, there must be a
source for a sound. The
source of a sound wave is
vibrating object which
produces the waves which
are nothing but the sound
waves.
 Longitudinal Wave.

3.  All sounds are produced by the vibrations of
material objects

4. When the Sound waves travels through the
medium, the pressure is exerted at the
particular points that creates two regions :
1. compression where pressure is more and
the density of the medium is more and
2. rarefaction where the pressure is less and
the density of the material is less.

6. The travelling wave which is an
oscillation of pressure transmitted
through a solid, liquid, or gas, composed
of frequencies within the range of
hearing.
 The speed of sound is 343.2 m/s or
1,126 ft/s.

8.  a body that has
the properties of
inertia and
elasticity set for
vibration: pianos,
violins, organ
pipes, saxophone
and vocal cords

9.  through air
 elastic material whether solid, liquid or gas.

10.  Human ear can hear the sound with a frequency
between 20-20,000 hertz

12.  
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13.  determined by the
amount of energy that
the sound wave carries
with it.
 the average rate of
flow of energy per unit
area perpendicular to
the direction of
propagation
 measured by decibels
(dB)

14.  involves a change in the direction
of waves as they pass from one
medium to another. Refraction,
or bending of the path of the
waves, is accompanied by a
change in speed and wavelength
of the waves. So if the media (or
its properties) are changed, the
speed of the wave is changed.
Thus, waves passing from one
medium to another will undergo
refraction.
 Refraction of sound waves is
most evident in situations in
which the sound wave passes
through a medium with gradually
varying properties.

15.  Reflection of a wave is the change in direction of a wave front at an
interface between two different media so that the wave front
returns into the medium from which it originated. The Common
examples include the reflection of light, sound and water waves.
When Sound wave travelilng in a medium strikes the surface
separating the two media,
A part of incident wave is reflected back into initial medium
obeying ordinary laws of reflection while the rest is partly absorbed
and partly refracted or transmitted into second medium.
 When a Longitudinal sounds wave strikes a flat surface, sound is
reflected in a coherent manner provided that the dimension of the
reflective surface is large compared to the wavelength of the
sound.

17.  The speed of sound in a medium depends on
the medium’s modulus of elasticity and its
density.
 The more elastic the medium, the faster is
the speed of sound.
 = 33.5 m/s =0.6T
where:
 = speed of sound
 T= temperature

18. Medium m/s Ft/s
Air 331.5 1,087
Carbon dioxide 258.0 846
Glass 5,500 18,050
Hydrogen 1.270 4,167
Iron 5.100 16,730
Water 1,450 4,757

20.  The speed of sound varies depending on altitude,
temperature and the medium through which it
travels. For example, at sea level in a standard
atmosphere, at a temperature of 59-degrees
Fahrenheit (15 Celsius), sound travels 761 miles per
hour (1,225 km/p/h). At a temperature of 32-degrees
Fahrenheit (0 Celsius) the speed of sound drops to
742 mph (1,194 km/p/h). In altitudes above sea level
the speed of sound is again different and will vary
depending on prevailing factors.

21. the height of
anything above a
given planetary
reference plane,
especially above
sea level on
earth.

22.  observed whenever the source of waves is moving
with respect to an observer
 can be described as the effect produced by a moving
source of waves in which there is an apparent upward
shift in frequency for observers towards whom the
source is approaching and an apparent downward
shift in frequency for observers from whom the
source is receding. It is important to note that the
effect does not result because of an actual change in
the frequency of the source.

24. bodies that
vibrate at a
regular rate
and have a
definite
frequency.

25.  bodies that do not vibrate at a regular rate.

26.  a signal or wave whose
frequency is an integral
(whole-number) multiple
of the frequency of some
reference signal or wave.
 also refer to the ratio of
the frequency of such a
signal or wave to the
frequency of the
reference signal or wave.

27.  a string
stretched
between two
points vibrates
when plucked
and a wave
travels along
the string.

30.  The fundamental frequency of vibration of a
stretched string is inversely proportional to its
length when its tension and linear density are
constant.
 Shorter strings produce notes of higher pitch.

31.  


 
.

32.  


 


33. 







34. • 
• 
• 
• 

• 