For a stationary siren on a firehouse is blaring at 81Hz. Assume the speed of sound to be 343m/s, the frequency perceived is mathematically given as'
F=81.721Hz
Generally, the equation for the doppler effect is mathematically given as
[tex]F'=\frac{vs+v}{vs}*f[/tex]
Therefore
F=81(343+3.05556)/343
F=81.721Hz
In conclusion, the frequency is
F=81.721Hz
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