Characteristics of sound:-
Pitch:-
1. The pitch of a sound is the characteristic which distinguishes between a shrill (or sharp) sound and a grave (or flat) sound.
2. A sound of high pitch is said to be shrill and its frequency is high
3. The sound of low pitch is said to be grave and its frequency is low
4. The pitch of female voice is higher than the pitch of male voice.
Quality:-
1. Sensation received by our ears due to wave form is known as quality or timbre.
2. The wave form depends on overtones present, quality of sound depends on number of overtones and their relative intensities.
3. We can recognize a person with out seeing him, by listening to his sound as it has a definite quality.
Loudness:-
1. The characteristic of sound on account of which the sound appears to be intense or slow is defined as loudness of sound.
2. The loudness depends on the intensity of sound and sensitivity of ear.
3. Loudness of a sound of given intensity may be different for different listeners.
The speed of sound in different media The speed of sound is nearly 5100m/s in steel
1450 m/s in water
330 m/s in air at 00c
Velocity of sound:-
Velocity of sound in any medium is given by newton's formula
\(
V = \sqrt {\frac{E}
{\rho }}
\)
Where E - is the modulus of elasticity of the medium , \(\rho\) - density
In gaseous:- In a gaseour medium v = \(
\sqrt {\frac{p}
{\rho }}
\)
According to newton who assumed that sound propagation in a gas take place under isothermal conditions. According to this formula velocity of sound in air is found to be 280 m/s at
N.T.P.
But experimental value is 331 m/s
Newton - Laplace formula for the velocity of sound in a gas after applying correction that sound propagation in a gaseous medium takes place under the adiabatic conditions (\(
Pv^\gamma = cons\tan t
\))
\(v = \sqrt {\frac{{\gamma p}}
{\rho }}
\)
where r is the ratio \(
\frac{{C_p }}
{{C_v }}
\) of the spavin heat of gas.
This is formula gives the correct value of velocity of sound in air at STP.
Note: Under constant temperature since \(
\sqrt {\frac{p}
{\rho }}
\) is constant. The velocity of sound in a gas does not change with pressure.