Calculate the Doppler shift caused by a car as it passes an observer at 50Km/h. Assume that the car emits a so

Answer 1

I hope you realize that you haven't given us enough info to give you a definite answer...or it was simply cut off. But we can still calculate a ratio, assuming that the observer was stationary and that the car is now moving away from the observer. Lets go with the speed of sound being 344 m/s

f' = f * [v / (v + vs)]
f' = f * [344 / (344 + 50)]
f' = 0.873 * f

So the doppler-shifted frequency is exactly 172/197 times the original frequency.