Quantitative measurement of the Doppler shift at an ultrasonic frequency

Abstract

Two ultrasonic transducers, the receiver stationary at the end on a linear air track, and the source mounted on a moving glider, are the basis for a Doppler shift experiment. The source frequency and the shifted receiver frequency are fed into a digital phase detector circuit which produces an output difference frequency with a sinusoidal waveform. This Doppler shift frequency can be measured directly and compared with the shift predicted from theory.

Computer sound card assisted measurements of the acoustic Doppler effect for accelerated and unaccelerated sound sources

“…We find this capability to be advan tageous over other Doppler measurement methods [1][2][3] from an instructional standpoint. It gives the students a direct data set to work with, allowing them to exercise their data analy sis skills, including scientific use of a computer, data plot ting, and graphical interpretation.…”

Direct quantitative measurements of Doppler effects for sound sources with gravitational acceleration

“…Since practical considerations are of import, we provide the details of the experiment, such as the parameters and the equipment used. Due to its significance as a fundamental physics phenomenon, various forms of Doppler effect experiments have been proposed and conducted for some time: Doppler effect due to a wave source on a toy car 1 , on an air track 2,3,4 , in circular motion 5,6,7 , carried by a student 8 and in free fall 9,10 as well as the effect due to the motion of the receiver 11 have been studied. Demonstrations of Doppler effects from real cars have also been performed 12,13 .…”