Re: Doppler question

[Clarence Bennett <bennett@oakland.edu>]

> Relative motion is NOT all that matters in a sound wave, because there
> is a vibrating medium (air). Motion of the source is not equivalent to
> motion of the observer. There's usuallly a simple conceptual derivation
> of the effect in any basic book.
> J. Epstein

Consider the limit case. If the listener approaches at the speed of sound
in the air, he should hear double the source frequency.
If the source moves at the speed of sound, the forward waves will
pile up into a shock wave and be heard as at infinite frequency.


Clarence Bennett
Oakland University
Rochester, Michigan
248 370 3418
http://www3.acs.oakland.edu/physics/staff_info/Bennett.htm