Theory:

A sound wave can be explained completely by five characteristics; they are
  • Amplitude
  • Frequency
  • Time period
  • Wavelength
  • Velocity or speed
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Wave nature
  
Amplitude (\(A\)):
The wave's amplitude is the maximum displacement of medium particles from their original undisturbed positions when a wave passes through the medium. The sound will be loud if the vibration of a particle has a large amplitude and soft if the vibration has a small amplitude. 'A' stands for amplitude. The \(metre\) \(m\) is its SI unit.
Time period (\(T\)):
The time taken for one complete oscillation of a sound wave is called the time period of the sound wave.
Timeperiod=1Frequency
Frequency (\(F\)):
The number of oscillations an object takes per second is called its frequency.
The SI unit of frequency is \(Hertz\) (\(Hz\)).
Frequency=TotalnumberofoscillationsTotaltimetaken
  
Velocity or Speed of the sound (\(v\)):
 
The speed of sound is defined as the distance that sound travels in one second. The letter ‘\(v\)' stands for it.
 
It is mathematically represented as,
 
v=nλ
 
where '\(n\)' is the frequency and 'λ' is the wavelength.
 
Distance travelled by the sound wave is found by,
 
Distance(d)=Numberofwaves×Wavelength(λ)
 
Example:
 
A sound has a frequency of \(70\) \(Hz\) and a wavelength of \(10\) \(m\). What is the speed of the sound?
 
Solution:
  
Frequency (\(n\)) \(=\) \(70\) \(Hz\)
 
Wavelength (\(λ\)) \(=\) \(10\) \(m\)
  
To find: Speed of the sound (\(v\))
 
We know the formula,
 
v=nλ
 
By applying these values we get,
 
\(v\) \(=\) 70 ·10
 
\(v\) \(=\) 700m/s