Explanation:
Let [tex]c[/tex] be the speed of sound in medium.
Let [tex]v_{s}[/tex] be the speed of the source.
Let [tex]v_{o}[/tex] be the speed of the observer.
Let [tex]f[/tex] be the frequency emitted by the source when the source is in rest.
Let [tex]f_{new}[/tex] be the frequency observed by the observer.
When the observer is moving away and the source is at rest,
[tex]f_{new}=f\times \dfrac{c-v_{o}}{c}[/tex]
Given,
[tex]c=344ms^{-1}[/tex]
[tex]v_{s}=0ms^{-1}[/tex]
[tex]v_{o}=22.4ms^{-1}[/tex]
[tex]f=1045Hz[/tex]
[tex]f_{new}=1045\times \frac{344-22.4}{344}=1045\times \frac{321.6}{344}=976.95Hz[/tex]
