Anything that moves back and forth makes sound. Moving back and forth is called vibrating. Pluck a guitar string and watch it vibrate back and forth. The vibrations make sound waves.

7. Anything that moves back and
forth makes sound. Moving
back and forth is called
vibrating. Pluck a guitar string
and watch it vibrate back and
forth. The vibrations make
sound waves.
Anything that moves back and
forth makes sound. Moving
back and forth is called
vibrating. Pluck a guitar string
and watch it vibrate back and
forth. The vibrations make
sound waves.

17. Sound waves are a lotSound waves are a lot
like water waves. If youlike water waves. If you
throw a pebble in a lakethrow a pebble in a lake
or pond, you can see theor pond, you can see the
waves move out inwaves move out in
circles. Sound wavescircles. Sound waves
move out in circles frommove out in circles from
whatever is vibrating.whatever is vibrating.

19. Musical Instruments &their Vibrating Parts
 MUSICAL
INSTRUMENTS
1. Veena
2. Tabla
3. Flute
4. Drum
5. Guitar
6. Trumpet
7. Cymbals
8. Noot
 VIBRATING PARTS
PRODUCING SOUNDS
 Stretched string
 Stretched membrane
 Air-column
 …
 ….
 ….
 ….
 ….

20. Sound Produced by HumanSound Produced by Human

24. In the human larynx, two pairs of vocal
cords are present. They are made of elastic
connective tissue covered by folds of
mucous membrane. One pair, the false
vocal cords, extends from the epiglottis to
the angle of the thyroid cartilage; these
cords narrow the glottis (the pharyngeal
opening of the larynx) during swallowing.
Below the false cords are the true vocal
cords, extending from the arytenoid
cartilages to the angle of the thyroid
cartilage. Vibration of this pair of cords by
air passing out of the lungs causes the
formation of sounds that are amplified by
the resonating nature of the voice box.

26. Anything that moves back
and forth makes sound.
Moving back and forth is
called vibrating. Pluck a
guitar string and watch it
vibrate back and forth. The
vibrations make sound
waves.

27. Sound is produced when
something vibrates. The
vibrating body causes the
medium (water, air, etc.)
around it to vibrate.
Vibrations in air are called
traveling longitudinal
waves, which we can hear.

28. Any simple sound, such as a musical
note, may be completely described by
specifying three perceptual
characteristics: pitch, loudness (or
intensity), and quality (or timbre).
These characteristics correspond exactly
to three physical characteristics:
frequency, amplitude, and harmonic
constitution, or waveform, respectively.
Noise is a complex sound, a mixture of
many different frequencies or notes not
harmonically related.

32. If a string that is fixed on both
ends is bowed or plucked, such
as in a violin, vibrations are
formed that are in a standing
wave pattern, having nodes at
the fixed ends, and an antinode
in the center. Several
harmonics are also produced,
in a similar way to the standing
wave.

35. You have an ear on each
side of your head. Your
ears let you hear sounds.
You can hear music and
other nice sounds. You
can hear sirens and other
warning sounds.

37. The human ear is divided into three
parts: the outer ear, the middle ear, and
the inner ear. The outer ear includes the
visible part of the ear that is attached to
the side of the head and the ear canal.
The eardrum separates the outer ear
from the middle ear, which is an air-filled
cavity. Inside this cavity are tiny bones
that vibrate when sound waves pass
through them. These bones help send
sound into the inner ear. The inner ear
contains an organ that helps you keep
your balance and another organ that
passes sound waves to the brain.

39. Sound, physical phenomenon that
stimulates the sense of hearing. In
humans, hearing takes place whenever
vibrations of frequencies from 15 hertz
to about 20,000 hertz reach the inner
ear. The hertz (Hz) is a unit of frequency
equaling one vibration or cycle per
second. Such vibrations reach the inner
ear when they are transmitted through
air. The speed of sound varies, but at sea
level it travels through cool, dry air at
about 1,190 km/h (740 mph). The term
sound is sometimes restricted to such
airborne vibrational waves. Modern
physicists,

41. OSCILLATION
Oscillation is the repeated motion
back and forth past a central neutral
position, or position of equilibrium. A
single motion from one extreme position to
the other and back, passing through the
neutral position twice, is called a cycle.

42. FREQUENCY
• The number of cycles per second, or hertz
(Hz), is known as the frequency of the
oscillation.

44. The amplitude of a sound wave is the
degree of motion of air molecules within
the wave, which corresponds to the
changes in air pressure that accompany
the wave. The greater the amplitude of the
wave, the harder the molecules strike the
eardrum and the louder the sound that is
perceived.

45. PITCH
Pitch (music), highness or
lowness of a musical tone as
determined by the rapidity of the
vibrations producing it.
The frequency determines the
shrillness or pitch of a sound.

46. LOUDNESS
The loudness or intensity of a noise is
measured in a unit called the decibel. The
softest audible sound to humans is 0
decibels, while painful sounds are those
that rise above 140 decibels.
• Loudness of sound depends on its
amplitude. It is proportional to the square
of the amplitude of the vibration producing
the sound.

47. NOISE AND MUSIC

48. At its simplest, music consists of a short,
unaccompanied melody, known as
monophony. But even the simplest melody
consists of many important components.
Some of the most obvious of these are the
varying heights or pitches of the tones,
their durations, their loudnesses, their tone
colors or timbres, and their articulations.

49. MUSIC
Music can be happy, sad, romantic,
sleepy, spine-tingling, healing—all kinds of
things. But what is it? Some people define
it as an artful arrangement of sounds
across time. Our ears interpret these
sounds as loud or soft, high or low, rapid
and short, or slow and smooth. The
sounds need to continue for a time in
some sort of pattern to become music.

50. MUSIC
Music, artful arrangement of sounds
across time. This definition is obviously
very broad, but a narrower one would
exclude too much. Music is part of virtually
every culture on Earth, but it varies widely
among cultures in style and structure.

51. NOISE
Noise is a complex sound, a mixture of
many different frequencies or notes not
harmonically related.

52. NOISE POLLUTION
• Sounds of vehicles
• Explosions
• Bursting of crackers
• Machines
• Loudspeakers
• Factories
• --------
• -------
• ------

53. HARMS OF
NOISE POLLUTION

54. • Lack of sleep
• Hypertension
• Anxiety
• Imparting of hearing
• -------
• -------
• -------

56. • USE OF SILENCING DEVICES IN
VECHILES
• RUN TV & MUSIC SYSTEM AT LOW
VOLUME
• PLANTATION OF TREES.