Va = 65mi/h * 1600m/mi * 1h/3600s = 28.9 m/s.
F1 = (Vs+Vp)/(Vs-Va) * Fa.
F1 = (330+0)/(330-28.9) * 500 = 548.0 Hz.
F2 = (330-0)/(330+28.9) * 500 = 459.7 Hz.
F1-F2 = 548 - 459.7 = 88.3 Hz. = Total shift in freq.
The siren of an ambulance has a frequency f=500 Hz. A pedestrian standing on a
sidewalk listens to this siren as the ambulance passes by at a speed of 65 mph. The speed
of sound in air is 330 m/s.
a) Calculate the total shift in frequency detected by the pedestrian as the ambulance
passes.
1 answer