4. PROPAGATION OF SOUND WAVES
Sound waves need medium propagation
Sound is produced by the vibration of an object, and sounds
require a medium to be heard. A medium is a substance that
transmits sound and can be liquid, gaseous, or solid.
5. PROPAGATION OF SOUND WAVES
Properties of Sound Wave Amplitude:
The amplitude of the sound is the magnitude of the maximum disturbance
in a sound wave.
The amplitude is also a measure of energy.
Time period:
The time taken to complete one vibration is known as time-period is called
as Time-period.
A time period is denoted by “T”.
The S.I unit is “sec”.
Frequency of sound:
The number of rarefactions and compressions that occur per unit of time is
known as frequency.
It is denoted by “f”.
Speed of sound:
The speed at which sound waves propagate through a medium is known as
the speed of sound.
6. PROPAGATION OF SOUND WAVES
Characteristics of Sound Waves
LOUDNESS
Loudness of sound is the property of sound that depends on the energy of the wave. It is
expressed in decibel (dB) and is directly proportional to the square of the amplitude of the sound wave.
7. PROPAGATION OF SOUND WAVES
PITCH OR SHRILLNESS
It is a characteristics by which an acute or shrill sound can be distinquish from a grave
or flate sound.
Pitch depends on its frequency.
8. PROPAGATION OF SOUND WAVES
QUALITY OR TIMBRE
It is that characteristics of sound which distinquishes the two sounds of same
loudness and same pitch but emitted by two different sources of sound.
9. PROPAGATION OF SOUND WAVES
Music
It is a pleasant , continuous and uniform sound produced
by regular and periodic vibrations.
Noise
It is a non periodic irregular and discontinuous disturbance.
10. PROPAGATION OF SOUND WAVES
Reflection of Sound
Reflection of sound is similar to the reflection of light. The reflection of sound obeys
the following laws of reflection
The angle of incidence is equal to the angle of reflection.
The incident sound, the normal sound and the normal sound all lie in the same plane.
11. PROPAGATION OF SOUND WAVES
Speed of Sound
The speed at which sound waves propagate through a medium is known as the
speed of sound.
