Example of Doppler Shift using car horn

This is an example of Doppler shift using a car horn. This minivan was filmed going by at approximately 40-50 MPH. The frequency shift in the horn is quite evident as the car passes.
UPDATE Aug 2022. We made this video back in 2007 for my father-in-law, Prof. David Bowen, of Wayne State University for use in his undergraduate Physics classes. He passed away recently, and we'd like to dedicate this video to him and his love of teaching. Miss you, Gramps.