If only the medium moves there is no influence on the observed frequency, but if I calculate the case where everything moves I get:
f’ = f * [ (v+vm-vo)/(v+vm-vb) ]
with f’ the observed frequency, f the transmitted frequency, v the wave speed in the medium, vm the speed of the medium, eg the speed of the source and vo the speed of the receiver.
In the calculation, all velocities in the same direction are parallel to each other.
Asker: Vic, 20 years
Answer
You can simplify the expression a bit if you express the velocities of source and receiver relative to the medium instead of relative to the ground. This is simply a coordinate transformation to a coordinate system pinned to the medium.
Answered by
Prof Walter Lauriks
Physics Acoustics
Catholic University of Leuven
Old Market 13 3000 Leuven
https://www.kuleuven.be/
Old Market 13 3000 Leuven
https://www.kuleuven.be/
.